working textarea with example, time to prepare it for the future implementations

first textarea implementation
renamed capital lettered functions and fixed examples
2025-08-17 12:17:46 +02:00 · 2025-08-17 11:01:38 +02:00 · 2025-08-16 23:10:50 +02:00 · 2025-08-15 00:06:54 +02:00 · 2025-08-15 00:06:19 +02:00 · 2025-08-14 14:23:08 +02:00
80 changed files with 16221 additions and 2373 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@ server/tantivy_indexes
 steel_decimal/tests/property_tests.proptest-regressions
 .direnv/
 canvas/*.toml
+.aider*
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -384,9 +384,9 @@ dependencies = [

 [[package]]
 name = "bon"
-version = "3.6.4"
+version = "3.6.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f61138465baf186c63e8d9b6b613b508cd832cba4ce93cf37ce5f096f91ac1a6"
+checksum = "33d9ef19ae5263a138da9a86871eca537478ab0332a7770bac7e3f08b801f89f"
 dependencies = [
 "bon-macros",
 "rustversion",
@@ -394,11 +394,11 @@ dependencies = [

 [[package]]
 name = "bon-macros"
-version = "3.6.4"
+version = "3.6.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "40d1dad34aa19bf02295382f08d9bc40651585bd497266831d40ee6296fb49ca"
+checksum = "577ae008f2ca11ca7641bd44601002ee5ab49ef0af64846ce1ab6057218a5cc1"
 dependencies = [
- "darling",
+ "darling 0.21.0",
 "ident_case",
 "prettyplease",
 "proc-macro2",
@@ -479,6 +479,7 @@ dependencies = [
 "common",
 "crossterm",
 "ratatui",
+ "regex",
 "serde",
 "thiserror",
 "tokio",
@@ -497,18 +498,18 @@ checksum = "df8670b8c7b9dae1793364eafadf7239c40d669904660c5960d74cfd80b46a53"

 [[package]]
 name = "castaway"
-version = "0.2.3"
+version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0abae9be0aaf9ea96a3b1b8b1b55c602ca751eba1b1500220cea4ecbafe7c0d5"
+checksum = "dec551ab6e7578819132c713a93c022a05d60159dc86e7a7050223577484c55a"
 dependencies = [
 "rustversion",
 ]

 [[package]]
 name = "cc"
-version = "1.2.29"
+version = "1.2.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5c1599538de2394445747c8cf7935946e3cc27e9625f889d979bfb2aaf569362"
+checksum = "deec109607ca693028562ed836a5f1c4b8bd77755c4e132fc5ce11b0b6211ae7"
 dependencies = [
 "jobserver",
 "libc",
@@ -653,9 +654,9 @@ checksum = "c2459377285ad874054d797f3ccebf984978aa39129f6eafde5cdc8315b612f8"

 [[package]]
 name = "const_panic"
-version = "0.2.12"
+version = "0.2.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2459fc9262a1aa204eb4b5764ad4f189caec88aea9634389c0a25f8be7f6265e"
+checksum = "b98d1483e98c9d67f341ab4b3915cfdc54740bd6f5cccc9226ee0535d86aa8fb"

 [[package]]
 name = "core-foundation"
@@ -714,9 +715,9 @@ checksum = "19d374276b40fb8bbdee95aef7c7fa6b5316ec764510eb64b8dd0e2ed0d7e7f5"

 [[package]]
 name = "crc32fast"
-version = "1.4.2"
+version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a97769d94ddab943e4510d138150169a2758b5ef3eb191a9ee688de3e23ef7b3"
+checksum = "9481c1c90cbf2ac953f07c8d4a58aa3945c425b7185c9154d67a65e4230da511"
 dependencies = [
 "cfg-if",
 ]
@@ -811,8 +812,18 @@ version = "0.20.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fc7f46116c46ff9ab3eb1597a45688b6715c6e628b5c133e288e709a29bcb4ee"
 dependencies = [
- "darling_core",
- "darling_macro",
+ "darling_core 0.20.11",
+ "darling_macro 0.20.11",
+]
+
+[[package]]
+name = "darling"
+version = "0.21.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a79c4acb1fd5fa3d9304be4c76e031c54d2e92d172a393e24b19a14fe8532fe9"
+dependencies = [
+ "darling_core 0.21.0",
+ "darling_macro 0.21.0",
 ]

 [[package]]
@@ -829,13 +840,38 @@ dependencies = [
 "syn 2.0.104",
 ]

+[[package]]
+name = "darling_core"
+version = "0.21.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "74875de90daf30eb59609910b84d4d368103aaec4c924824c6799b28f77d6a1d"
+dependencies = [
+ "fnv",
+ "ident_case",
+ "proc-macro2",
+ "quote",
+ "strsim",
+ "syn 2.0.104",
+]
+
 [[package]]
 name = "darling_macro"
 version = "0.20.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fc34b93ccb385b40dc71c6fceac4b2ad23662c7eeb248cf10d529b7e055b6ead"
 dependencies = [
- "darling_core",
+ "darling_core 0.20.11",
+ "quote",
+ "syn 2.0.104",
+]
+
+[[package]]
+name = "darling_macro"
+version = "0.21.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e79f8e61677d5df9167cd85265f8e5f64b215cdea3fb55eebc3e622e44c7a146"
+dependencies = [
+ "darling_core 0.21.0",
 "quote",
 "syn 2.0.104",
 ]
@@ -959,7 +995,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "778e2ac28f6c47af28e4907f13ffd1e1ddbd400980a9abd7c8df189bf578a5ad"
 dependencies = [
 "libc",
- "windows-sys 0.60.2",
+ "windows-sys 0.52.0",
 ]

 [[package]]
@@ -1430,9 +1466,9 @@ dependencies = [

 [[package]]
 name = "hyper-util"
-version = "0.1.15"
+version = "0.1.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f66d5bd4c6f02bf0542fad85d626775bab9258cf795a4256dcaf3161114d1df"
+checksum = "8d9b05277c7e8da2c93a568989bb6207bef0112e8d17df7a6eda4a3cf143bc5e"
 dependencies = [
 "bytes",
 "futures-channel",
@@ -1443,7 +1479,7 @@ dependencies = [
 "hyper",
 "libc",
 "pin-project-lite",
- "socket2",
+ "socket2 0.6.0",
 "tokio",
 "tower-service",
 "tracing",
@@ -1612,9 +1648,9 @@ dependencies = [

 [[package]]
 name = "im-lists"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "88485149c4fcec01ebce4e4b8284a3c75b3d8a4749169f5481144e6433e9bcd2"
+checksum = "8b971d2652e5700514cc92ca020dba64c790352af0ff2b9acb7514868a32d6aa"
 dependencies = [
 "smallvec",
 ]
@@ -1671,11 +1707,11 @@ dependencies = [

 [[package]]
 name = "instability"
-version = "0.3.7"
+version = "0.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0bf9fed6d91cfb734e7476a06bde8300a1b94e217e1b523b6f0cd1a01998c71d"
+checksum = "435d80800b936787d62688c927b6490e887c7ef5ff9ce922c6c6050fca75eb9a"
 dependencies = [
- "darling",
+ "darling 0.20.11",
 "indoc",
 "proc-macro2",
 "quote",
@@ -1684,9 +1720,9 @@ dependencies = [

 [[package]]
 name = "io-uring"
-version = "0.7.8"
+version = "0.7.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b86e202f00093dcba4275d4636b93ef9dd75d025ae560d2521b45ea28ab49013"
+checksum = "d93587f37623a1a17d94ef2bc9ada592f5465fe7732084ab7beefabe5c77c0c4"
 dependencies = [
 "bitflags",
 "cfg-if",
@@ -1803,9 +1839,9 @@ checksum = "f9fbbcab51052fe104eb5e5d351cf728d30a5be1fe14d9be8a3b097481fb97de"

 [[package]]
 name = "libredox"
-version = "0.1.4"
+version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1580801010e535496706ba011c15f8532df6b42297d2e471fec38ceadd8c0638"
+checksum = "4488594b9328dee448adb906d8b126d9b7deb7cf5c22161ee591610bb1be83c0"
 dependencies = [
 "bitflags",
 "libc",
@@ -1903,9 +1939,9 @@ checksum = "32a282da65faaf38286cf3be983213fcf1d2e2a58700e808f83f4ea9a4804bc0"

 [[package]]
 name = "memmap2"
-version = "0.9.5"
+version = "0.9.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fd3f7eed9d3848f8b98834af67102b720745c4ec028fcd0aa0239277e7de374f"
+checksum = "483758ad303d734cec05e5c12b41d7e93e6a6390c5e9dae6bdeb7c1259012d28"
 dependencies = [
 "libc",
 ]
@@ -2293,17 +2329,16 @@ checksum = "7edddbd0b52d732b21ad9a5fab5c704c14cd949e5e9a1ec5929a24fded1b904c"

 [[package]]
 name = "polling"
-version = "3.8.0"
+version = "3.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b53a684391ad002dd6a596ceb6c74fd004fdce75f4be2e3f615068abbea5fd50"
+checksum = "8ee9b2fa7a4517d2c91ff5bc6c297a427a96749d15f98fcdbb22c05571a4d4b7"
 dependencies = [
 "cfg-if",
 "concurrent-queue",
 "hermit-abi",
 "pin-project-lite",
- "rustix 1.0.7",
- "tracing",
- "windows-sys 0.59.0",
+ "rustix 1.0.8",
+ "windows-sys 0.60.2",
 ]

 [[package]]
@@ -2343,9 +2378,9 @@ dependencies = [

 [[package]]
 name = "prettyplease"
-version = "0.2.35"
+version = "0.2.36"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "061c1221631e079b26479d25bbf2275bfe5917ae8419cd7e34f13bfc2aa7539a"
+checksum = "ff24dfcda44452b9816fff4cd4227e1bb73ff5a2f1bc1105aa92fb8565ce44d2"
 dependencies = [
 "proc-macro2",
 "syn 2.0.104",
@@ -2507,9 +2542,9 @@ dependencies = [

 [[package]]
 name = "rand"
-version = "0.9.1"
+version = "0.9.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9fbfd9d094a40bf3ae768db9361049ace4c0e04a4fd6b359518bd7b73a73dd97"
+checksum = "6db2770f06117d490610c7488547d543617b21bfa07796d7a12f6f1bd53850d1"
 dependencies = [
 "rand_chacha 0.9.0",
 "rand_core 0.9.3",
@@ -2615,9 +2650,9 @@ dependencies = [

 [[package]]
 name = "redox_syscall"
-version = "0.5.13"
+version = "0.5.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0d04b7d0ee6b4a0207a0a7adb104d23ecb0b47d6beae7152d0fa34b692b29fd6"
+checksum = "7e8af0dde094006011e6a740d4879319439489813bd0bcdc7d821beaeeff48ec"
 dependencies = [
 "bitflags",
 ]
@@ -2846,20 +2881,20 @@ dependencies = [
 "errno",
 "libc",
 "linux-raw-sys 0.4.15",
- "windows-sys 0.59.0",
+ "windows-sys 0.52.0",
 ]

 [[package]]
 name = "rustix"
-version = "1.0.7"
+version = "1.0.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c71e83d6afe7ff64890ec6b71d6a69bb8a610ab78ce364b3352876bb4c801266"
+checksum = "11181fbabf243db407ef8df94a6ce0b2f9a733bd8be4ad02b4eda9602296cac8"
 dependencies = [
 "bitflags",
 "errno",
 "libc",
 "linux-raw-sys 0.9.4",
- "windows-sys 0.59.0",
+ "windows-sys 0.52.0",
 ]

 [[package]]
@@ -2963,9 +2998,9 @@ dependencies = [

 [[package]]
 name = "serde_json"
-version = "1.0.140"
+version = "1.0.141"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "20068b6e96dc6c9bd23e01df8827e6c7e1f2fddd43c21810382803c136b99373"
+checksum = "30b9eff21ebe718216c6ec64e1d9ac57087aad11efc64e32002bce4a0d4c03d3"
 dependencies = [
 "itoa",
 "memchr",
@@ -3009,7 +3044,7 @@ dependencies = [
 "lazy_static",
 "prost",
 "prost-types",
- "rand 0.9.1",
+ "rand 0.9.2",
 "regex",
 "rstest",
 "rust-stemmers",
@@ -3173,6 +3208,16 @@ dependencies = [
 "windows-sys 0.52.0",
 ]

+[[package]]
+name = "socket2"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "233504af464074f9d066d7b5416c5f9b894a5862a6506e306f7b816cdd6f1807"
+dependencies = [
+ "libc",
+ "windows-sys 0.59.0",
+]
+
 [[package]]
 name = "spin"
 version = "0.9.8"
@@ -3447,7 +3492,7 @@ dependencies = [
 "parking_lot",
 "polling",
 "quickscope",
- "rand 0.9.1",
+ "rand 0.9.2",
 "serde",
 "serde_json",
 "smallvec",
@@ -3462,9 +3507,9 @@ dependencies = [

 [[package]]
 name = "steel-decimal"
-version = "1.0.0"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c43950a3eed43f3e9765a51f5dc1b0de5e1687ba824b8589990747d9ba241187"
+checksum = "4cd8a6d1a41d2146705b29292cac75c78a3e32d7b6cabb72d808209546615f37"
 dependencies = [
 "regex",
 "rust_decimal",
@@ -3599,9 +3644,9 @@ dependencies = [

 [[package]]
 name = "tantivy"
-version = "0.24.1"
+version = "0.24.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ca2374a21157427c5faff2d90930f035b6c22a5d7b0e5b0b7f522e988ef33c06"
+checksum = "64a966cb0e76e311f09cf18507c9af192f15d34886ee43d7ba7c7e3803660c43"
 dependencies = [
 "aho-corasick",
 "arc-swap",
@@ -3758,8 +3803,8 @@ dependencies = [
 "fastrand",
 "getrandom 0.3.3",
 "once_cell",
- "rustix 1.0.7",
- "windows-sys 0.59.0",
+ "rustix 1.0.8",
+ "windows-sys 0.52.0",
 ]

 [[package]]
@@ -3873,7 +3918,7 @@ dependencies = [
 "pin-project-lite",
 "signal-hook-registry",
 "slab",
- "socket2",
+ "socket2 0.5.10",
 "tokio-macros",
 "windows-sys 0.52.0",
 ]
@@ -3987,7 +4032,7 @@ dependencies = [
 "percent-encoding",
 "pin-project",
 "prost",
- "socket2",
+ "socket2 0.5.10",
 "tokio",
 "tokio-stream",
 "tower",
@@ -4276,7 +4321,7 @@ version = "0.20.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b7df16e474ef958526d1205f6dda359fdfab79d9aa6d54bafcb92dcd07673dca"
 dependencies = [
- "darling",
+ "darling 0.20.11",
 "once_cell",
 "proc-macro-error2",
 "proc-macro2",
@@ -4404,7 +4449,7 @@ checksum = "24d643ce3fd3e5b54854602a080f34fb10ab75e0b813ee32d00ca2b44fa74762"
 dependencies = [
 "either",
 "env_home",
- "rustix 1.0.7",
+ "rustix 1.0.8",
 "winsafe",
 ]

@@ -4440,7 +4485,7 @@ version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cf221c93e13a30d793f7645a0e7762c55d169dbb0a49671918a2319d289b10bb"
 dependencies = [
- "windows-sys 0.59.0",
+ "windows-sys 0.48.0",
 ]

 [[package]]
@@ -4731,9 +4776,9 @@ checksum = "271414315aff87387382ec3d271b52d7ae78726f5d44ac98b4f4030c91880486"

 [[package]]
 name = "winnow"
-version = "0.7.11"
+version = "0.7.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "74c7b26e3480b707944fc872477815d29a8e429d2f93a1ce000f5fa84a15cbcd"
+checksum = "f3edebf492c8125044983378ecb5766203ad3b4c2f7a922bd7dd207f6d443e95"
 dependencies = [
 "memchr",
 ]
--- a/canvas/.gitignore
+++ b/canvas/.gitignore
@@ -0,0 +1 @@
+docs_prompts/
--- a/canvas/CANVAS_MIGRATION.md
+++ b/canvas/CANVAS_MIGRATION.md
@@ -2,7 +2,7 @@

 ## Overview

-This guide covers the migration from the legacy canvas library structure to the new clean, modular architecture. The new design separates core canvas functionality from autocomplete features, providing better type safety and maintainability.
+This guide covers the migration from the legacy canvas library structure to the new clean, modular architecture. The new design separates core canvas functionality from suggestions features, providing better type safety and maintainability.

 ## Key Changes

@@ -10,7 +10,7 @@ This guide covers the migration from the legacy canvas library structure to the
 ```
 # Old Structure (LEGACY)
 src/
-├── state.rs              # Mixed canvas + autocomplete
+├── state.rs              # Mixed canvas + suggestions
 ├── actions/edit.rs       # Mixed concerns
 ├── gui/render.rs         # Everything together
 └── suggestions.rs        # Legacy file
@@ -21,9 +21,9 @@ src/
 │   ├── state.rs         # CanvasState trait only
 │   ├── actions/edit.rs  # Canvas actions only
 │   └── gui.rs           # Canvas rendering
-├── autocomplete/         # Rich autocomplete features
-│   ├── state.rs         # AutocompleteCanvasState trait
-│   ├── types.rs         # SuggestionItem, AutocompleteState
+├── suggestions/         # Suggestions dropdown features (not inline autocomplete)
+│   ├── state.rs         # Suggestion provider types
+│   ├── gui.rs           # Suggestions dropdown rendering
 │   ├── actions.rs       # Autocomplete actions
 │   └── gui.rs           # Autocomplete dropdown rendering
 └── dispatcher.rs         # Action routing
@@ -31,7 +31,7 @@ src/

 ### 2. **Trait Separation**
 - **CanvasState**: Core form functionality (navigation, input, validation)
- **AutocompleteCanvasState**: Optional rich autocomplete features
+- Suggestions module: Optional dropdown suggestions support

 ### 3. **Rich Suggestions**
 Replaced simple string suggestions with typed, rich suggestion objects.
@@ -93,34 +93,29 @@ impl CanvasState for YourFormState {

 ### Step 3: Implement Rich Autocomplete (Optional)

-**If you want rich autocomplete features:**
+**If you want suggestions dropdown features:**

 ```rust
-use canvas::autocomplete::{AutocompleteCanvasState, SuggestionItem, AutocompleteState};
+use canvas::{SuggestionItem};

-impl AutocompleteCanvasState for YourFormState {
-    type SuggestionData = YourDataType; // e.g., Hit, CustomRecord, etc.
-
-    fn supports_autocomplete(&self, field_index: usize) -> bool {
-        // Define which fields support autocomplete
+impl YourFormState {
+    fn supports_suggestions(&self, field_index: usize) -> bool {
+        // Define which fields support suggestions
        matches!(field_index, 2 | 3 | 5) // Example: only certain fields
    }

-    fn autocomplete_state(&self) -> Option<&AutocompleteState<Self::SuggestionData>> {
-        Some(&self.autocomplete)
-    }
+    // Manage your own suggestion state or rely on FormEditor APIs

-    fn autocomplete_state_mut(&mut self) -> Option<&mut AutocompleteState<Self::SuggestionData>> {
-        Some(&mut self.autocomplete)
-    }
+    // Manage your own suggestion state or rely on FormEditor APIs
 }
 ```

-**Add autocomplete field to your state:**
+**Add suggestions storage to your state (optional, if you need to persist outside the editor):**
 ```rust
 pub struct YourFormState {
    // ... existing fields
-    pub autocomplete: AutocompleteState<YourDataType>,
+    // Optional: your own suggestions cache if needed
+    // pub suggestion_cache: Vec<SuggestionItem>,
 }
 ```

@@ -149,9 +144,9 @@ form_state.set_autocomplete_suggestions(suggestions);

 **Old rendering:**
 ```rust
-// Manual autocomplete rendering
-if form_state.autocomplete_active {
-    render_autocomplete_dropdown(/* ... */);
+// Manual suggestions rendering
+if editor.is_suggestions_active() {
+    suggestions::gui::render_suggestions_dropdown(/* ... */);
 }
 ```

@@ -162,13 +157,12 @@ use canvas::canvas::render_canvas;

 let active_field_rect = render_canvas(f, area, form_state, theme, edit_mode, highlight_state);

-// Optional: Rich autocomplete (if implementing AutocompleteCanvasState)
-if form_state.is_autocomplete_active() {
-    if let Some(autocomplete_state) = form_state.autocomplete_state() {
-        canvas::autocomplete::render_autocomplete_dropdown(
-            f, f.area(), active_field_rect.unwrap(), theme, autocomplete_state
-        );
-    }
+// Suggestions dropdown (if active)
+if editor.is_suggestions_active() {
+    canvas::suggestions::render_suggestions_dropdown(
+        f, f.area(), active_field_rect.unwrap(), theme, &editor
+    );
+}
 }
 ```

@@ -181,16 +175,16 @@ form_state.deactivate_suggestions();

 # NEW - Option A: Add your own method
 impl YourFormState {
-    pub fn deactivate_autocomplete(&mut self) {
+    pub fn deactivate_suggestions(&mut self) {
        self.autocomplete_active = false;
        self.autocomplete_suggestions.clear();
        self.selected_suggestion_index = None;
    }
 }
-form_state.deactivate_autocomplete();
+editor.ui_state_mut().deactivate_suggestions();

-# NEW - Option B: Use rich autocomplete trait
-form_state.deactivate_autocomplete(); // If implementing AutocompleteCanvasState
+# NEW - Option B: Suggestions via editor APIs
+editor.ui_state_mut().deactivate_suggestions();
 ```

 ## Benefits of New Architecture
@@ -217,8 +211,8 @@ let suggestions: Vec<SuggestionItem<UserRecord>> = vec![
 - **Display Overrides**: Show friendly text while storing normalized data

 ### 4. **Future-Proof**
- Easy to add new autocomplete features
- Canvas features don't interfere with autocomplete
+- Easy to add new suggestion features
+- Canvas features don't interfere with suggestions
 - Modular: Use only what you need

 ## Advanced Features
@@ -262,7 +256,7 @@ SuggestionItem::new(user, "John Doe (Manager)".to_string(), "123".to_string());
 ## Breaking Changes Summary

 1. **Import paths changed**: Add `canvas::` or `dispatcher::` prefixes
-2. **Legacy suggestion methods removed**: Replace with rich autocomplete or custom methods
+2. **Legacy suggestion methods removed**: Replace with SuggestionItem-based dropdown or custom methods
 3. **No more simple suggestions**: Use `SuggestionItem` for typed suggestions
 4. **Trait split**: `AutocompleteCanvasState` is now separate and optional

@@ -283,11 +277,11 @@ SuggestionItem::new(user, "John Doe (Manager)".to_string(), "123".to_string());

 - [ ] Updated all import paths
 - [ ] Removed legacy methods from CanvasState implementation
- [ ] Added custom autocomplete methods if needed
- [ ] Updated suggestion usage to SuggestionItem
+- [ ] Added custom suggestion methods if needed
+- [ ] Updated usage to SuggestionItem
 - [ ] Updated rendering calls
 - [ ] Tested form functionality
- [ ] Tested autocomplete functionality (if using)
+- [ ] Tested suggestions functionality (if using)

 ## Example: Complete Migration

@@ -305,29 +299,25 @@ impl CanvasState for FormState {
 **After:**
 ```rust
 use canvas::canvas::{CanvasState, CanvasAction};
-use canvas::autocomplete::{AutocompleteCanvasState, SuggestionItem};
+use canvas::SuggestionItem;

 impl CanvasState for FormState {
-    // Only core canvas methods, no suggestion methods
+    // Only core canvas methods
    fn current_field(&self) -> usize { /* ... */ }
    fn get_current_input(&self) -> &str { /* ... */ }
    // ... other core methods only
 }

-impl AutocompleteCanvasState for FormState {
+// Use FormEditor + SuggestionsProvider for suggestions dropdown
    type SuggestionData = Hit;
    
-    fn supports_autocomplete(&self, field_index: usize) -> bool {
+    fn supports_suggestions(&self, field_index: usize) -> bool {
        self.fields[field_index].is_link
    }
    
-    fn autocomplete_state(&self) -> Option<&AutocompleteState<Self::SuggestionData>> {
-        Some(&self.autocomplete)
-    }
+    // Maintain suggestion state through FormEditor and DataProvider
    
-    fn autocomplete_state_mut(&mut self) -> Option<&mut AutocompleteState<Self::SuggestionData>> {
-        Some(&mut self.autocomplete)
-    }
+    // Maintain suggestion state through FormEditor and DataProvider
 }
 ```

--- a/canvas/Cargo.toml
+++ b/canvas/Cargo.toml
@@ -12,32 +12,71 @@ categories.workspace = true
 [dependencies]
 common = { path = "../common" }
 ratatui = { workspace = true, optional = true }
-crossterm = { workspace = true }
-anyhow = { workspace = true }
+crossterm = { workspace = true, optional = true }
+anyhow.workspace = true
 tokio = { workspace = true, optional = true }
 toml = { workspace = true }
-serde = { workspace = true }
+serde.workspace = true
 unicode-width.workspace = true
 thiserror = { workspace = true }

 tracing = "0.1.41"
 tracing-subscriber = "0.3.19"
-async-trait = { workspace = true, optional = true }
+async-trait.workspace = true
+regex = { workspace = true, optional = true }

 [dev-dependencies]
 tokio-test = "0.4.4"

 [features]
 default = []
-gui = ["ratatui"]
-autocomplete = ["tokio", "async-trait"]
+gui = ["ratatui", "crossterm"]
+suggestions = ["tokio"]
+cursor-style = ["crossterm"]
+validation = ["regex"]
+computed = []
+textarea = ["gui"]

 [[example]]
-name = "autocomplete"
-required-features = ["autocomplete", "gui"]
-path = "examples/autocomplete.rs"
+name = "suggestions"
+required-features = ["suggestions", "gui", "cursor-style"]
+path = "examples/suggestions.rs"

 [[example]]
-name = "canvas_gui_demo"
-required-features = ["gui"]
-path = "examples/canvas_gui_demo.rs"
+name = "suggestions2"
+required-features = ["suggestions", "gui", "cursor-style"]
+path = "examples/suggestions2.rs"
+
+[[example]]
+name = "canvas_cursor_auto"
+required-features = ["gui", "cursor-style"]
+path = "examples/canvas_cursor_auto.rs"
+
+[[example]]
+name = "validation_1"
+required-features = ["gui", "validation", "cursor-style"]
+
+[[example]]
+name = "validation_2"
+required-features = ["gui", "validation", "cursor-style"]
+
+[[example]]
+name = "validation_3"
+required-features = ["gui", "validation", "cursor-style"]
+
+[[example]]
+name = "validation_4"
+required-features = ["gui", "validation", "cursor-style"]
+
+[[example]]
+name = "validation_5"
+required-features = ["gui", "validation", "cursor-style"]
+
+[[example]]
+name = "computed_fields"
+required-features = ["gui", "computed"]
+
+[[example]]
+name = "canvas_textarea_cursor_auto"
+required-features = ["gui", "cursor-style", "textarea"]
+path = "examples/canvas_textarea_cursor_auto.rs"
--- a/canvas/README.md
+++ b/canvas/README.md
@@ -7,7 +7,7 @@ A reusable, type-safe canvas system for building form-based TUI applications wit
 - **Type-Safe Actions**: No more string-based action names - everything is compile-time checked
 - **Generic Design**: Implement `CanvasState` once, get navigation, editing, and suggestions for free
 - **Vim-Like Experience**: Modal editing with familiar keybindings
- **Suggestion System**: Built-in autocomplete and suggestions support
+- **Suggestion System**: Built-in suggestions dropdown support
 - **Framework Agnostic**: Works with any TUI framework or raw terminal handling
 - **Async Ready**: Full async/await support for modern Rust applications
 - **Batch Operations**: Execute multiple actions atomically
@@ -144,7 +144,7 @@ pub enum CanvasAction {

 ## 🔧 Advanced Features

-### Suggestions and Autocomplete
+### Suggestions Dropdown (not inline autocomplete)

 ```rust
 impl CanvasState for MyForm {
@@ -170,7 +170,7 @@ impl CanvasState for MyForm {
            CanvasAction::SelectSuggestion => {
                if let Some(suggestion) = self.suggestions.get_selected() {
                    *self.get_current_input_mut() = suggestion.clone();
-                    self.deactivate_autocomplete();
+                    self.deactivate_suggestions();
                    Some("Applied suggestion".to_string())
                }
                None
--- a/canvas/docs/new_function_to_config.txt
+++ b/canvas/docs/new_function_to_config.txt
@@ -1,77 +0,0 @@
-❯ git status
-On branch main
-Your branch is ahead of 'origin/main' by 1 commit.
-  (use "git push" to publish your local commits)
-
-Changes not staged for commit:
-  (use "git add <file>..." to update what will be committed)
-  (use "git restore <file>..." to discard changes in working directory)
-	modified:   src/canvas/actions/handlers/edit.rs
-	modified:   src/canvas/actions/types.rs
-
-no changes added to commit (use "git add" and/or "git commit -a")
-❯ git --no-pager diff
-diff --git a/canvas/src/canvas/actions/handlers/edit.rs b/canvas/src/canvas/actions/handlers/edit.rs
-index a26fe6f..fa1becb 100644
--- a/canvas/src/canvas/actions/handlers/edit.rs
-+++ b/canvas/src/canvas/actions/handlers/edit.rs
-@@ -29,6 +29,21 @@ pub async fn handle_edit_action<S: CanvasState>(
-             Ok(ActionResult::success())
-         }
-
-+        CanvasAction::SelectAll => {
-+            // Select all text in current field
-+            let current_input = state.get_current_input();
-+            let text_length = current_input.len();
-+
-+            // Set cursor to start and select all
-+            state.set_current_cursor_pos(0);
-+            // TODO: You'd need to add selection state to CanvasState trait
-+            // For now, just move cursor to end to "select" all
-+            state.set_current_cursor_pos(text_length);
-+            *ideal_cursor_column = text_length;
-+
-+            Ok(ActionResult::success_with_message(&format!("Selected all {} characters", text_length)))
-+        }
-+
-         CanvasAction::DeleteBackward => {
-             let cursor_pos = state.current_cursor_pos();
-             if cursor_pos > 0 {
-@@ -323,6 +338,13 @@ impl ActionHandlerIntrospection for EditHandler {
-             is_required: false,
-         });
-
-+        actions.push(ActionSpec {
-+            name: "select_all".to_string(),
-+            description: "Select all text in current field".to_string(),
-+            examples: vec!["Ctrl+a".to_string()],
-+            is_required: false, // Optional action
-+        });
-+
-         HandlerCapabilities {
-             mode_name: "edit".to_string(),
-             actions,
-diff --git a/canvas/src/canvas/actions/types.rs b/canvas/src/canvas/actions/types.rs
-index 433a4d5..3794596 100644
--- a/canvas/src/canvas/actions/types.rs
-+++ b/canvas/src/canvas/actions/types.rs
-@@ -31,6 +31,8 @@ pub enum CanvasAction {
-     NextField,
-     PrevField,
-
-+    SelectAll,
-+
-     // Autocomplete actions
-     TriggerAutocomplete,
-     SuggestionUp,
-@@ -62,6 +64,7 @@ impl CanvasAction {
-             "move_word_end_prev" => Self::MoveWordEndPrev,
-             "next_field" => Self::NextField,
-             "prev_field" => Self::PrevField,
-+            "select_all" => Self::SelectAll,
-             "trigger_autocomplete" => Self::TriggerAutocomplete,
-             "suggestion_up" => Self::SuggestionUp,
-             "suggestion_down" => Self::SuggestionDown,
-╭─      ~/Doc/p/komp_ac/canvas  on    main ⇡1 !2 
-╰─
-
--- a/canvas/examples/autocomplete.rs
+++ b/canvas/examples/autocomplete.rs
@@ -1,417 +0,0 @@
-// examples/autocomplete.rs
-// Run with: cargo run --example autocomplete --features "autocomplete,gui"
-
-use std::io;
-use crossterm::{
-    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers},
-    execute,
-    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
-};
-use ratatui::{
-    backend::{Backend, CrosstermBackend},
-    layout::{Constraint, Direction, Layout},
-    style::Color,
-    text::{Line, Span},
-    widgets::{Block, Borders, Paragraph},
-    Frame, Terminal,
-};
-
-use canvas::{
-    canvas::{
-        gui::render_canvas,
-        modes::AppMode,
-        state::{ActionContext, CanvasState},
-        theme::CanvasTheme,
-    },
-    autocomplete::{
-        AutocompleteCanvasState,
-        AutocompleteState,
-        SuggestionItem,
-        execute_with_autocomplete,
-        handle_autocomplete_feature_action,
-    },
-    CanvasAction,
-};
-
-// Add the async_trait import
-use async_trait::async_trait;
-
-// Simple theme implementation
-#[derive(Clone)]
-struct DemoTheme;
-
-impl CanvasTheme for DemoTheme {
-    fn bg(&self) -> Color { Color::Reset }
-    fn fg(&self) -> Color { Color::White }
-    fn accent(&self) -> Color { Color::Cyan }
-    fn secondary(&self) -> Color { Color::Gray }
-    fn highlight(&self) -> Color { Color::Yellow }
-    fn highlight_bg(&self) -> Color { Color::DarkGray }
-    fn warning(&self) -> Color { Color::Red }
-    fn border(&self) -> Color { Color::Gray }
-}
-
-// Custom suggestion data type
-#[derive(Clone, Debug)]
-struct EmailSuggestion {
-    email: String,
-    provider: String,
-}
-
-// Demo form state with autocomplete
-struct AutocompleteFormState {
-    fields: Vec<String>,
-    field_names: Vec<String>,
-    current_field: usize,
-    cursor_pos: usize,
-    mode: AppMode,
-    has_changes: bool,
-    debug_message: String,
-
-    // Autocomplete state
-    autocomplete: AutocompleteState<EmailSuggestion>,
-}
-
-impl AutocompleteFormState {
-    fn new() -> Self {
-        Self {
-            fields: vec![
-                "John Doe".to_string(),
-                "john@".to_string(), // Partial email to demonstrate autocomplete
-                "+1 234 567 8900".to_string(),
-                "San Francisco".to_string(),
-            ],
-            field_names: vec![
-                "Name".to_string(),
-                "Email".to_string(),
-                "Phone".to_string(),
-                "City".to_string(),
-            ],
-            current_field: 1, // Start on email field
-            cursor_pos: 5, // Position after "john@"
-            mode: AppMode::Edit,
-            has_changes: false,
-            debug_message: "Type in email field, Tab to trigger autocomplete, Enter to select, Esc to cancel".to_string(),
-            autocomplete: AutocompleteState::new(),
-        }
-    }
-}
-
-impl CanvasState for AutocompleteFormState {
-    fn current_field(&self) -> usize { self.current_field }
-    fn current_cursor_pos(&self) -> usize { self.cursor_pos }
-    fn set_current_field(&mut self, index: usize) {
-        self.current_field = index.min(self.fields.len().saturating_sub(1));
-        // Clear autocomplete when changing fields
-        if self.is_autocomplete_active() {
-            self.clear_autocomplete_suggestions();
-        }
-    }
-    fn set_current_cursor_pos(&mut self, pos: usize) {
-        let max_pos = if self.mode == AppMode::Edit {
-            self.fields[self.current_field].len()
-        } else {
-            self.fields[self.current_field].len().saturating_sub(1)
-        };
-        self.cursor_pos = pos.min(max_pos);
-    }
-    fn current_mode(&self) -> AppMode { self.mode }
-    fn get_current_input(&self) -> &str { &self.fields[self.current_field] }
-    fn get_current_input_mut(&mut self) -> &mut String { &mut self.fields[self.current_field] }
-    fn inputs(&self) -> Vec<&String> { self.fields.iter().collect() }
-    fn fields(&self) -> Vec<&str> { self.field_names.iter().map(|s| s.as_str()).collect() }
-    fn has_unsaved_changes(&self) -> bool { self.has_changes }
-    fn set_has_unsaved_changes(&mut self, changed: bool) { self.has_changes = changed; }
-
-    fn handle_feature_action(&mut self, action: &CanvasAction, _context: &ActionContext) -> Option<String> {
-        // Handle autocomplete actions first
-        if let Some(result) = handle_autocomplete_feature_action(action, self) {
-            return Some(result);
-        }
-
-        // Handle other custom actions
-        match action {
-            CanvasAction::Custom(cmd) => {
-                match cmd.as_str() {
-                    "toggle_mode" => {
-                        self.mode = match self.mode {
-                            AppMode::Edit => AppMode::ReadOnly,
-                            AppMode::ReadOnly => AppMode::Edit,
-                            _ => AppMode::Edit,
-                        };
-                        Some(format!("Switched to {:?} mode", self.mode))
-                    }
-                    _ => None,
-                }
-            }
-            _ => None,
-        }
-    }
-}
-
-// Add the #[async_trait] attribute to the implementation
-#[async_trait]
-impl AutocompleteCanvasState for AutocompleteFormState {
-    type SuggestionData = EmailSuggestion;
-
-    fn supports_autocomplete(&self, field_index: usize) -> bool {
-        // Only enable autocomplete for email field (index 1)
-        field_index == 1
-    }
-
-    fn autocomplete_state(&self) -> Option<&AutocompleteState<Self::SuggestionData>> {
-        Some(&self.autocomplete)
-    }
-
-    fn autocomplete_state_mut(&mut self) -> Option<&mut AutocompleteState<Self::SuggestionData>> {
-        Some(&mut self.autocomplete)
-    }
-
-    fn should_trigger_autocomplete(&self) -> bool {
-        let current_input = self.get_current_input();
-        let current_field = self.current_field();
-
-        // Trigger for email field when we have "@" and at least 1 more character
-        self.supports_autocomplete(current_field) &&
-        current_input.contains('@') &&
-        current_input.len() > current_input.find('@').unwrap_or(0) + 1 &&
-        !self.is_autocomplete_active()
-    }
-
-    /// This is where the magic happens - user implements their own async fetching
-    async fn trigger_autocomplete_suggestions(&mut self) {
-        // 1. Activate UI (shows loading spinner)
-        self.activate_autocomplete();
-        self.set_autocomplete_loading(true);
-
-        // 2. Get current input for querying
-        let query = self.get_current_input().to_string();
-
-        // 3. Extract domain part from email
-        let domain_part = if let Some(at_pos) = query.find('@') {
-            query[at_pos + 1..].to_string()
-        } else {
-            self.set_autocomplete_loading(false);
-            return; // No @ symbol, can't suggest
-        };
-
-        // 4. SIMULATE ASYNC API CALL (in real code, this would be HTTP request)
-        let email_prefix = query[..query.find('@').unwrap()].to_string();
-        let suggestions = tokio::task::spawn_blocking(move || {
-            // Simulate network delay
-            std::thread::sleep(std::time::Duration::from_millis(200));
-
-            // Create mock suggestions based on domain input
-            let popular_domains = vec![
-                ("gmail.com", "Gmail"),
-                ("yahoo.com", "Yahoo Mail"),
-                ("outlook.com", "Outlook"),
-                ("hotmail.com", "Hotmail"),
-                ("company.com", "Company Email"),
-                ("university.edu", "University"),
-            ];
-
-            let mut results = Vec::new();
-
-            for (domain, provider) in popular_domains {
-                if domain.starts_with(&domain_part) || domain_part.is_empty() {
-                    let full_email = format!("{}@{}", email_prefix, domain);
-                    results.push(SuggestionItem::new(
-                        EmailSuggestion {
-                            email: full_email.clone(),
-                            provider: provider.to_string(),
-                        },
-                        format!("{} ({})", full_email, provider), // display text
-                        full_email, // value to store
-                    ));
-                }
-            }
-
-            results
-        }).await.unwrap_or_default();
-
-        // 5. Provide suggestions back to library
-        self.set_autocomplete_suggestions(suggestions);
-    }
-}
-
-async fn handle_key_press(key: KeyCode, modifiers: KeyModifiers, state: &mut AutocompleteFormState) -> bool {
-    if key == KeyCode::F(10) || (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL)) {
-        return false; // Quit
-    }
-
-    let action = match key {
-        // === AUTOCOMPLETE KEYS ===
-        KeyCode::Tab => {
-            if state.is_autocomplete_active() {
-                Some(CanvasAction::SuggestionDown) // Navigate suggestions
-            } else if state.supports_autocomplete(state.current_field()) {
-                Some(CanvasAction::TriggerAutocomplete) // Manual trigger
-            } else {
-                Some(CanvasAction::NextField) // Normal tab
-            }
-        }
-
-        KeyCode::BackTab => {
-            if state.is_autocomplete_active() {
-                Some(CanvasAction::SuggestionUp)
-            } else {
-                Some(CanvasAction::PrevField)
-            }
-        }
-
-        KeyCode::Enter => {
-            if state.is_autocomplete_active() {
-                Some(CanvasAction::SelectSuggestion) // Apply suggestion
-            } else {
-                Some(CanvasAction::NextField)
-            }
-        }
-
-        KeyCode::Esc => {
-            if state.is_autocomplete_active() {
-                Some(CanvasAction::ExitSuggestions) // Close autocomplete
-            } else {
-                Some(CanvasAction::Custom("toggle_mode".to_string()))
-            }
-        }
-
-        // === STANDARD CANVAS KEYS ===
-        KeyCode::Left => Some(CanvasAction::MoveLeft),
-        KeyCode::Right => Some(CanvasAction::MoveRight),
-        KeyCode::Up => Some(CanvasAction::MoveUp),
-        KeyCode::Down => Some(CanvasAction::MoveDown),
-        KeyCode::Home => Some(CanvasAction::MoveLineStart),
-        KeyCode::End => Some(CanvasAction::MoveLineEnd),
-        KeyCode::Backspace => Some(CanvasAction::DeleteBackward),
-        KeyCode::Delete => Some(CanvasAction::DeleteForward),
-
-        // Character input
-        KeyCode::Char(c) if !modifiers.contains(KeyModifiers::CONTROL) => {
-            Some(CanvasAction::InsertChar(c))
-        }
-
-        _ => None,
-    };
-
-    if let Some(action) = action {
-        match execute_with_autocomplete(action.clone(), state).await {
-            Ok(result) => {
-                if let Some(msg) = result.message() {
-                    state.debug_message = msg.to_string();
-                } else {
-                    state.debug_message = format!("Executed: {:?}", action);
-                }
-                true
-            }
-            Err(e) => {
-                state.debug_message = format!("Error: {}", e);
-                true
-            }
-        }
-    } else {
-        state.debug_message = format!("Unhandled key: {:?}", key);
-        true
-    }
-}
-
-async fn run_app<B: Backend>(terminal: &mut Terminal<B>, mut state: AutocompleteFormState) -> io::Result<()> {
-    let theme = DemoTheme;
-
-    loop {
-        terminal.draw(|f| ui(f, &state, &theme))?;
-
-        if let Event::Key(key) = event::read()? {
-            let should_continue = handle_key_press(key.code, key.modifiers, &mut state).await;
-            if !should_continue {
-                break;
-            }
-        }
-    }
-
-    Ok(())
-}
-
-fn ui(f: &mut Frame, state: &AutocompleteFormState, theme: &DemoTheme) {
-    let chunks = Layout::default()
-        .direction(Direction::Vertical)
-        .constraints([
-            Constraint::Min(8),
-            Constraint::Length(5),
-        ])
-        .split(f.area());
-
-    // Render the canvas form
-    let active_field_rect = render_canvas(
-        f,
-        chunks[0],
-        state,
-        theme,
-        state.mode == AppMode::Edit,
-        &canvas::HighlightState::Off,
-    );
-
-    // Render autocomplete dropdown on top if active
-    if let Some(input_rect) = active_field_rect {
-        canvas::render_autocomplete_dropdown(
-            f,
-            chunks[0],
-            input_rect,
-            theme,
-            &state.autocomplete,
-        );
-    }
-
-    // Status info
-    let autocomplete_status = if state.is_autocomplete_active() {
-        if state.autocomplete.is_loading {
-            "Loading suggestions..."
-        } else if state.has_autocomplete_suggestions() {
-            "Use Tab/Shift+Tab to navigate, Enter to select, Esc to cancel"
-        } else {
-            "No suggestions found"
-        }
-    } else {
-        "Tab to trigger autocomplete"
-    };
-
-    let status_lines = vec![
-        Line::from(Span::raw(format!("Mode: {:?} | Field: {}/{} | Cursor: {}",
-            state.mode, state.current_field + 1, state.fields.len(), state.cursor_pos))),
-        Line::from(Span::raw(format!("Autocomplete: {}", autocomplete_status))),
-        Line::from(Span::raw(state.debug_message.clone())),
-        Line::from(Span::raw("F10: Quit | Tab: Trigger/Navigate autocomplete | Enter: Select | Esc: Cancel/Toggle mode")),
-    ];
-
-    let status = Paragraph::new(status_lines)
-        .block(Block::default().borders(Borders::ALL).title("Status & Help"));
-
-    f.render_widget(status, chunks[1]);
-}
-
-#[tokio::main]
-async fn main() -> Result<(), Box<dyn std::error::Error>> {
-    enable_raw_mode()?;
-    let mut stdout = io::stdout();
-    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
-    let backend = CrosstermBackend::new(stdout);
-    let mut terminal = Terminal::new(backend)?;
-
-    let state = AutocompleteFormState::new();
-
-    let res = run_app(&mut terminal, state).await;
-
-    disable_raw_mode()?;
-    execute!(
-        terminal.backend_mut(),
-        LeaveAlternateScreen,
-        DisableMouseCapture
-    )?;
-    terminal.show_cursor()?;
-
-    if let Err(err) = res {
-        println!("{:?}", err);
-    }
-
-    Ok(())
-}
--- a/canvas/examples/canvas_cursor_auto.rs
+++ b/canvas/examples/canvas_cursor_auto.rs
@@ -0,0 +1,866 @@
+// examples/canvas-cursor-auto.rs
+//! Demonstrates automatic cursor management with the canvas library
+//!
+//! This example REQUIRES the `cursor-style` feature to compile.
+//! 
+//! Run with:
+//! cargo run --example canvas_cursor_auto --features "gui,cursor-style"
+//!
+//! This will fail without cursor-style:
+//! cargo run --example canvas-cursor-auto --features "gui"
+
+// REQUIRE cursor-style feature - example won't compile without it
+#[cfg(not(feature = "cursor-style"))]
+compile_error!(
+    "This example requires the 'cursor-style' feature. \
+     Run with: cargo run --example canvas-cursor-auto --features \"gui,cursor-style\""
+);
+
+use std::io;
+use crossterm::{
+    event::{
+        self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers,
+    },
+    execute,
+    terminal::{
+        disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen,
+    },
+};
+use ratatui::{
+    backend::{Backend, CrosstermBackend},
+    layout::{Constraint, Direction, Layout},
+    style::{Color, Style},
+    text::{Line, Span},
+    widgets::{Block, Borders, Paragraph},
+    Frame, Terminal,
+};
+
+use canvas::{
+    canvas::{
+        gui::render_canvas_default,
+        modes::{AppMode, ModeManager, HighlightState},
+        CursorManager, // This import only exists when cursor-style feature is enabled
+    },
+    DataProvider, FormEditor,
+};
+
+// Enhanced FormEditor that demonstrates automatic cursor management
+struct AutoCursorFormEditor<D: DataProvider> {
+    editor: FormEditor<D>,
+    has_unsaved_changes: bool,
+    debug_message: String,
+    command_buffer: String, // For multi-key vim commands like "gg"
+}
+
+impl<D: DataProvider> AutoCursorFormEditor<D> {
+    fn new(data_provider: D) -> Self {
+        Self {
+            editor: FormEditor::new(data_provider),
+            has_unsaved_changes: false,
+            debug_message: "🎯 Automatic Cursor Demo - cursor-style feature enabled!".to_string(),
+            command_buffer: String::new(),
+        }
+    }
+
+    // === COMMAND BUFFER HANDLING ===
+
+    fn clear_command_buffer(&mut self) {
+        self.command_buffer.clear();
+    }
+
+    fn add_to_command_buffer(&mut self, ch: char) {
+        self.command_buffer.push(ch);
+    }
+
+    fn get_command_buffer(&self) -> &str {
+        &self.command_buffer
+    }
+
+    fn has_pending_command(&self) -> bool {
+        !self.command_buffer.is_empty()
+    }
+
+    // === VISUAL/HIGHLIGHT MODE SUPPORT ===
+
+
+    fn enter_visual_mode(&mut self) {
+        // Use the library method instead of manual state setting
+        self.editor.enter_highlight_mode();
+        self.debug_message = "🔥 VISUAL MODE - Cursor: Blinking Block █".to_string();
+    }
+
+    fn enter_visual_line_mode(&mut self) {
+        // Use the library method instead of manual state setting  
+        self.editor.enter_highlight_line_mode();
+        self.debug_message = "🔥 VISUAL LINE MODE - Cursor: Blinking Block █".to_string();
+    }
+
+    fn exit_visual_mode(&mut self) {
+        // Use the library method
+        self.editor.exit_highlight_mode();
+        self.debug_message = "🔒 NORMAL MODE - Cursor: Steady Block █".to_string();
+    }
+
+    fn update_visual_selection(&mut self) {
+        if self.editor.is_highlight_mode() {
+            use canvas::canvas::state::SelectionState;
+            match self.editor.selection_state() {
+                SelectionState::Characterwise { anchor } => {
+                    self.debug_message = format!(
+                        "🎯 Visual selection: anchor=({},{}) current=({},{}) - Cursor: Blinking Block █",
+                        anchor.0, anchor.1,
+                        self.editor.current_field(),
+                        self.editor.cursor_position()
+                    );
+                }
+                SelectionState::Linewise { anchor_field } => {
+                    self.debug_message = format!(
+                        "🎯 Visual LINE selection: anchor={} current={} - Cursor: Blinking Block █",
+                        anchor_field,
+                        self.editor.current_field()
+                    );
+                }
+                _ => {}
+            }
+        }
+    }
+
+    // === ENHANCED MOVEMENT WITH VISUAL UPDATES ===
+
+    fn move_left(&mut self) {
+        self.editor.move_left();
+        self.update_visual_selection();
+    }
+
+    fn move_right(&mut self) {
+        self.editor.move_right();
+        self.update_visual_selection();
+    }
+
+    fn move_up(&mut self) {
+        self.editor.move_up();
+        self.update_visual_selection();
+    }
+
+    fn move_down(&mut self) {
+        self.editor.move_down();
+        self.update_visual_selection();
+    }
+
+    fn move_word_next(&mut self) {
+        self.editor.move_word_next();
+        self.update_visual_selection();
+    }
+
+    fn move_word_prev(&mut self) {
+        self.editor.move_word_prev();
+        self.update_visual_selection();
+    }
+
+    fn move_word_end(&mut self) {
+        self.editor.move_word_end();
+        self.update_visual_selection();
+    }
+
+    fn move_word_end_prev(&mut self) {
+        self.editor.move_word_end_prev();
+        self.update_visual_selection();
+    }
+
+    fn move_line_start(&mut self) {
+        self.editor.move_line_start();
+        self.update_visual_selection();
+    }
+
+    fn move_line_end(&mut self) {
+        self.editor.move_line_end();
+        self.update_visual_selection();
+    }
+
+    fn move_first_line(&mut self) {
+        self.editor.move_first_line();
+        self.update_visual_selection();
+    }
+
+    fn move_last_line(&mut self) {
+        self.editor.move_last_line();
+        self.update_visual_selection();
+    }
+
+    fn prev_field(&mut self) {
+        self.editor.prev_field();
+        self.update_visual_selection();
+    }
+
+    fn next_field(&mut self) {
+        self.editor.next_field();
+        self.update_visual_selection();
+    }
+
+    // === DELETE OPERATIONS ===
+
+    fn delete_backward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_backward();
+        if result.is_ok() {
+            self.has_unsaved_changes = true;
+            self.debug_message = "⌫ Deleted character backward".to_string();
+        }
+        Ok(result?)
+    }
+
+    fn delete_forward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_forward();
+        if result.is_ok() {
+            self.has_unsaved_changes = true;
+            self.debug_message = "⌦ Deleted character forward".to_string();
+        }
+        Ok(result?)
+    }
+
+    // === MODE TRANSITIONS WITH AUTOMATIC CURSOR MANAGEMENT ===
+
+    fn enter_edit_mode(&mut self) {
+        self.editor.enter_edit_mode(); // 🎯 Library automatically sets cursor to bar |
+        self.debug_message = "✏️  INSERT MODE - Cursor: Steady Bar |".to_string();
+    }
+
+    fn enter_append_mode(&mut self) {
+        self.editor.enter_append_mode(); // 🎯 Library automatically positions cursor and sets mode
+        self.debug_message = "✏️  INSERT (append) - Cursor: Steady Bar |".to_string();
+    }
+
+    fn exit_edit_mode(&mut self) {
+        self.editor.exit_edit_mode(); // 🎯 Library automatically sets cursor to block █
+        self.exit_visual_mode();
+        self.debug_message = "🔒 NORMAL MODE - Cursor: Steady Block █".to_string();
+    }
+
+    fn insert_char(&mut self, ch: char) -> anyhow::Result<()> {
+        let result = self.editor.insert_char(ch);
+        if result.is_ok() {
+            self.has_unsaved_changes = true;
+        }
+        Ok(result?)
+    }
+
+    // === MANUAL CURSOR OVERRIDE DEMONSTRATION ===
+    
+    /// Demonstrate manual cursor control (for advanced users)
+    fn demo_manual_cursor_control(&mut self) -> std::io::Result<()> {
+        // Users can still manually control cursor if needed
+        CursorManager::update_for_mode(AppMode::Command)?;
+        self.debug_message = "🔧 Manual override: Command cursor _".to_string();
+        Ok(())
+    }
+
+    fn restore_automatic_cursor(&mut self) -> std::io::Result<()> {
+        // Restore automatic cursor based on current mode
+        CursorManager::update_for_mode(self.editor.mode())?;
+        self.debug_message = "🎯 Restored automatic cursor management".to_string();
+        Ok(())
+    }
+
+    // === DELEGATE TO ORIGINAL EDITOR ===
+
+    fn current_field(&self) -> usize {
+        self.editor.current_field()
+    }
+
+    fn cursor_position(&self) -> usize {
+        self.editor.cursor_position()
+    }
+
+    fn mode(&self) -> AppMode {
+        self.editor.mode()
+    }
+
+    fn current_text(&self) -> &str {
+        let field_index = self.editor.current_field();
+        self.editor.data_provider().field_value(field_index)
+    }
+
+    fn data_provider(&self) -> &D {
+        self.editor.data_provider()
+    }
+
+    fn ui_state(&self) -> &canvas::EditorState {
+        self.editor.ui_state()
+    }
+
+    fn set_mode(&mut self, mode: AppMode) {
+        self.editor.set_mode(mode); // 🎯 Library automatically updates cursor
+        if mode != AppMode::Highlight {
+            self.exit_visual_mode();
+        }
+    }
+
+    // === STATUS AND DEBUG ===
+
+    fn set_debug_message(&mut self, msg: String) {
+        self.debug_message = msg;
+    }
+
+    fn debug_message(&self) -> &str {
+        &self.debug_message
+    }
+
+    fn has_unsaved_changes(&self) -> bool {
+        self.has_unsaved_changes
+    }
+
+    fn open_line_below(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.open_line_below();
+        if result.is_ok() {
+            self.debug_message = "✏️  INSERT (open line below) - Cursor: Steady Bar |".to_string();
+        }
+        result
+    }
+
+    fn open_line_above(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.open_line_above();
+        if result.is_ok() {
+            self.debug_message = "✏️  INSERT (open line above) - Cursor: Steady Bar |".to_string();
+        }
+        result
+    }
+
+    fn move_big_word_next(&mut self) {
+        self.editor.move_big_word_next();
+        self.update_visual_selection();
+    }
+
+    fn move_big_word_prev(&mut self) {
+        self.editor.move_big_word_prev();
+        self.update_visual_selection();
+    }
+
+    fn move_big_word_end(&mut self) {
+        self.editor.move_big_word_end();
+        self.update_visual_selection();
+    }
+
+    fn move_big_word_end_prev(&mut self) {
+        self.editor.move_big_word_end_prev();
+        self.update_visual_selection();
+    }
+}
+
+// Demo form data with interesting text for cursor demonstration
+struct CursorDemoData {
+    fields: Vec<(String, String)>,
+}
+
+impl CursorDemoData {
+    fn new() -> Self {
+        Self {
+            fields: vec![
+                ("👤 Name".to_string(), "John-Paul McDonald".to_string()),
+                ("📧 Email".to_string(), "user@example-domain.com".to_string()),
+                ("📱 Phone".to_string(), "+1 (555) 123-4567".to_string()),
+                ("🏠 Address".to_string(), "123 Main St, Apt 4B".to_string()),
+                ("🏷️  Tags".to_string(), "urgent,important,follow-up".to_string()),
+                ("📝 Notes".to_string(), "Watch the cursor change! Normal=█ Insert=| Visual=blinking█".to_string()),
+                ("🎯 Cursor Demo".to_string(), "Press 'i' for insert, 'v' for visual, 'Esc' for normal".to_string()),
+            ],
+        }
+    }
+}
+
+impl DataProvider for CursorDemoData {
+    fn field_count(&self) -> usize {
+        self.fields.len()
+    }
+
+    fn field_name(&self, index: usize) -> &str {
+        &self.fields[index].0
+    }
+
+    fn field_value(&self, index: usize) -> &str {
+        &self.fields[index].1
+    }
+
+    fn set_field_value(&mut self, index: usize, value: String) {
+        self.fields[index].1 = value;
+    }
+
+    fn supports_suggestions(&self, _field_index: usize) -> bool {
+        false
+    }
+
+    fn display_value(&self, _index: usize) -> Option<&str> {
+        None
+    }
+}
+
+/// Automatic cursor management demonstration
+/// Features the CursorManager directly to show it's working
+fn handle_key_press(
+    key: KeyCode,
+    modifiers: KeyModifiers,
+    editor: &mut AutoCursorFormEditor<CursorDemoData>,
+) -> anyhow::Result<bool> {
+    let mode = editor.mode();
+
+    // Quit handling
+    if (key == KeyCode::Char('q') && modifiers.contains(KeyModifiers::CONTROL))
+        || (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL))
+        || key == KeyCode::F(10)
+    {
+        return Ok(false);
+    }
+
+    match (mode, key, modifiers) {
+        // === MODE TRANSITIONS WITH AUTOMATIC CURSOR MANAGEMENT ===
+        (AppMode::ReadOnly, KeyCode::Char('i'), _) => {
+            editor.enter_edit_mode(); // 🎯 Automatic: cursor becomes bar |
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('a'), _) => {
+            editor.enter_append_mode();
+            editor.set_debug_message("✏️  INSERT (append) - Cursor: Steady Bar |".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('A'), _) => {
+            editor.move_line_end();
+            editor.enter_edit_mode(); // 🎯 Automatic: cursor becomes bar |
+            editor.set_debug_message("✏️  INSERT (end of line) - Cursor: Steady Bar |".to_string());
+            editor.clear_command_buffer();
+        }
+
+        (AppMode::ReadOnly, KeyCode::Char('o'), _) => {
+            if let Err(e) = editor.open_line_below() {
+                editor.set_debug_message(format!("Error opening line below: {}", e));
+            }
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('O'), _) => {
+            if let Err(e) = editor.open_line_above() {
+                editor.set_debug_message(format!("Error opening line above: {}", e));
+            }
+            editor.clear_command_buffer();
+        }
+
+        // From Normal Mode: Enter visual modes
+        (AppMode::ReadOnly, KeyCode::Char('v'), _) => {
+            editor.enter_visual_mode();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('V'), _) => {
+            editor.enter_visual_line_mode();
+            editor.clear_command_buffer();
+        }
+        
+        // From Visual Mode: Switch between visual modes or exit
+        (AppMode::Highlight, KeyCode::Char('v'), _) => {
+            use canvas::canvas::state::SelectionState;
+            match editor.editor.selection_state() {
+                SelectionState::Characterwise { .. } => {
+                    // Already in characterwise mode, exit visual mode (vim behavior)
+                    editor.exit_visual_mode();
+                    editor.set_debug_message("🔒 Exited visual mode".to_string());
+                }
+                _ => {
+                    // Switch from linewise to characterwise mode
+                    editor.editor.enter_highlight_mode();
+                    editor.update_visual_selection();
+                    editor.set_debug_message("🔥 Switched to VISUAL mode".to_string());
+                }
+            }
+            editor.clear_command_buffer();
+        }
+        
+        (AppMode::Highlight, KeyCode::Char('V'), _) => {
+            use canvas::canvas::state::SelectionState;
+            match editor.editor.selection_state() {
+                SelectionState::Linewise { .. } => {
+                    // Already in linewise mode, exit visual mode (vim behavior)
+                    editor.exit_visual_mode();
+                    editor.set_debug_message("🔒 Exited visual mode".to_string());
+                }
+                _ => {
+                    // Switch from characterwise to linewise mode
+                    editor.editor.enter_highlight_line_mode();
+                    editor.update_visual_selection();
+                    editor.set_debug_message("🔥 Switched to VISUAL LINE mode".to_string());
+                }
+            }
+            editor.clear_command_buffer();
+        }
+        
+        // Escape: Exit any mode back to normal
+        (_, KeyCode::Esc, _) => {
+            match mode {
+                AppMode::Edit => {
+                    editor.exit_edit_mode(); // Exit insert mode
+                }
+                AppMode::Highlight => {
+                    editor.exit_visual_mode(); // Exit visual mode
+                }
+                _ => {
+                    // Already in normal mode, just clear command buffer
+                    editor.clear_command_buffer();
+                }
+            }
+        }
+
+        // === CURSOR MANAGEMENT DEMONSTRATION ===
+        (AppMode::ReadOnly, KeyCode::F(1), _) => {
+            editor.demo_manual_cursor_control()?;
+        }
+        (AppMode::ReadOnly, KeyCode::F(2), _) => {
+            editor.restore_automatic_cursor()?;
+        }
+
+        // === MOVEMENT: VIM-STYLE NAVIGATION ===
+
+        // Basic movement (hjkl and arrows)
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('h'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Left, _) => {
+            editor.move_left();
+            editor.set_debug_message("← left".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('l'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Right, _) => {
+            editor.move_right();
+            editor.set_debug_message("→ right".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('j'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Down, _) => {
+            editor.move_down();
+            editor.set_debug_message("↓ next field".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('k'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Up, _) => {
+            editor.move_up();
+            editor.set_debug_message("↑ previous field".to_string());
+            editor.clear_command_buffer();
+        }
+
+        // Word movement
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('w'), _) => {
+            editor.move_word_next();
+            editor.set_debug_message("w: next word start".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('b'), _) => {
+            editor.move_word_prev();
+            editor.set_debug_message("b: previous word start".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('e'), _) => {
+            // Check if this is 'ge' command
+            if editor.get_command_buffer() == "g" {
+                editor.move_word_end_prev();
+                editor.set_debug_message("ge: previous word end".to_string());
+                editor.clear_command_buffer();
+            } else {
+                editor.move_word_end();
+                editor.set_debug_message("e: word end".to_string());
+                editor.clear_command_buffer();
+            }
+        }
+
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('W'), _) => {
+            editor.move_big_word_next();
+            editor.set_debug_message("W: next WORD start".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('B'), _) => {
+            editor.move_big_word_prev();
+            editor.set_debug_message("B: previous WORD start".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('E'), _) => {
+            // Check if this is 'gE' command
+            if editor.get_command_buffer() == "g" {
+                editor.move_big_word_end_prev();
+                editor.set_debug_message("gE: previous WORD end".to_string());
+                editor.clear_command_buffer();
+            } else {
+                editor.move_big_word_end();
+                editor.set_debug_message("E: WORD end".to_string());
+                editor.clear_command_buffer();
+            }
+        }
+
+        // Line movement
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('0'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Home, _) => {
+            editor.move_line_start();
+            editor.set_debug_message("0: line start".to_string());
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('$'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::End, _) => {
+            editor.move_line_end();
+            editor.set_debug_message("$: line end".to_string());
+        }
+
+        // Field/document movement
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('g'), _) => {
+            if editor.get_command_buffer() == "g" {
+                editor.move_first_line();
+                editor.set_debug_message("gg: first field".to_string());
+                editor.clear_command_buffer();
+            } else {
+                editor.clear_command_buffer();
+                editor.add_to_command_buffer('g');
+                editor.set_debug_message("g".to_string());
+            }
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('G'), _) => {
+            editor.move_last_line();
+            editor.set_debug_message("G: last field".to_string());
+            editor.clear_command_buffer();
+        }
+
+        // === EDIT MODE MOVEMENT ===
+        (AppMode::Edit, KeyCode::Left, m) if m.contains(KeyModifiers::CONTROL) => {
+            editor.move_word_prev();
+            editor.set_debug_message("Ctrl+← word back".to_string());
+        }
+        (AppMode::Edit, KeyCode::Right, m) if m.contains(KeyModifiers::CONTROL) => {
+            editor.move_word_next();
+            editor.set_debug_message("Ctrl+→ word forward".to_string());
+        }
+        (AppMode::Edit, KeyCode::Left, _) => {
+            editor.move_left();
+        }
+        (AppMode::Edit, KeyCode::Right, _) => {
+            editor.move_right();
+        }
+        (AppMode::Edit, KeyCode::Up, _) => {
+            editor.move_up();
+        }
+        (AppMode::Edit, KeyCode::Down, _) => {
+            editor.move_down();
+        }
+        (AppMode::Edit, KeyCode::Home, _) => {
+            editor.move_line_start();
+        }
+        (AppMode::Edit, KeyCode::End, _) => {
+            editor.move_line_end();
+        }
+
+        // === DELETE OPERATIONS ===
+        (AppMode::Edit, KeyCode::Backspace, _) => {
+            editor.delete_backward()?;
+        }
+        (AppMode::Edit, KeyCode::Delete, _) => {
+            editor.delete_forward()?;
+        }
+
+        // Delete operations in normal mode (vim x)
+        (AppMode::ReadOnly, KeyCode::Char('x'), _) => {
+            editor.delete_forward()?;
+            editor.set_debug_message("x: deleted character".to_string());
+        }
+        (AppMode::ReadOnly, KeyCode::Char('X'), _) => {
+            editor.delete_backward()?;
+            editor.set_debug_message("X: deleted character backward".to_string());
+        }
+
+        // === TAB NAVIGATION ===
+        (_, KeyCode::Tab, _) => {
+            editor.next_field();
+            editor.set_debug_message("Tab: next field".to_string());
+        }
+        (_, KeyCode::BackTab, _) => {
+            editor.prev_field();
+            editor.set_debug_message("Shift+Tab: previous field".to_string());
+        }
+
+        // === CHARACTER INPUT ===
+        (AppMode::Edit, KeyCode::Char(c), m) if !m.contains(KeyModifiers::CONTROL) => {
+            editor.insert_char(c)?;
+        }
+
+        // === DEBUG/INFO COMMANDS ===
+        (AppMode::ReadOnly, KeyCode::Char('?'), _) => {
+            editor.set_debug_message(format!(
+                "Field {}/{}, Pos {}, Mode: {:?} - Cursor managed automatically!",
+                editor.current_field() + 1,
+                editor.data_provider().field_count(),
+                editor.cursor_position(),
+                editor.mode()
+            ));
+        }
+
+        _ => {
+            if editor.has_pending_command() {
+                editor.clear_command_buffer();
+                editor.set_debug_message("Invalid command sequence".to_string());
+            } else {
+                editor.set_debug_message(format!(
+                    "Unhandled: {:?} + {:?} in {:?} mode",
+                    key, modifiers, mode
+                ));
+            }
+        }
+    }
+
+    Ok(true)
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut editor: AutoCursorFormEditor<CursorDemoData>,
+) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f, &editor))?;
+
+        if let Event::Key(key) = event::read()? {
+            match handle_key_press(key.code, key.modifiers, &mut editor) {
+                Ok(should_continue) => {
+                    if !should_continue {
+                        break;
+                    }
+                }
+                Err(e) => {
+                    editor.set_debug_message(format!("Error: {}", e));
+                }
+            }
+        }
+    }
+
+    Ok(())
+}
+
+fn ui(f: &mut Frame, editor: &AutoCursorFormEditor<CursorDemoData>) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Min(8), Constraint::Length(10)])
+        .split(f.area());
+
+    render_enhanced_canvas(f, chunks[0], editor);
+    render_status_and_help(f, chunks[1], editor);
+}
+
+fn render_enhanced_canvas(
+    f: &mut Frame,
+    area: ratatui::layout::Rect,
+    editor: &AutoCursorFormEditor<CursorDemoData>,
+) {
+    render_canvas_default(f, area, &editor.editor);
+}
+
+fn render_status_and_help(
+    f: &mut Frame,
+    area: ratatui::layout::Rect,
+    editor: &AutoCursorFormEditor<CursorDemoData>,
+) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Length(3), Constraint::Length(7)])
+        .split(area);
+
+    // Status bar with cursor information - FIXED VERSION
+    let mode_text = match editor.mode() {
+        AppMode::Edit => "INSERT | (bar cursor)",
+        AppMode::ReadOnly => "NORMAL █ (block cursor)",
+        AppMode::Highlight => {
+            // Use library selection state instead of editor.highlight_state()
+            use canvas::canvas::state::SelectionState;
+            match editor.editor.selection_state() {
+                SelectionState::Characterwise { .. } => "VISUAL █ (blinking block)",
+                SelectionState::Linewise { .. } => "VISUAL LINE █ (blinking block)",
+                _ => "VISUAL █ (blinking block)",
+            }
+        },
+        _ => "NORMAL █ (block cursor)",
+    };
+
+    let status_text = if editor.has_pending_command() {
+        format!("-- {} -- {} [{}]", mode_text, editor.debug_message(), editor.get_command_buffer())
+    } else if editor.has_unsaved_changes() {
+        format!("-- {} -- [Modified] {}", mode_text, editor.debug_message())
+    } else {
+        format!("-- {} -- {}", mode_text, editor.debug_message())
+    };
+
+    let status = Paragraph::new(Line::from(Span::raw(status_text)))
+        .block(Block::default().borders(Borders::ALL).title("🎯 Automatic Cursor Status"));
+
+    f.render_widget(status, chunks[0]);
+
+    // Enhanced help text (no changes needed here)
+    let help_text = match editor.mode() {
+        AppMode::ReadOnly => {
+            if editor.has_pending_command() {
+                match editor.get_command_buffer() {
+                    "g" => "Press 'g' again for first field, or any other key to cancel",
+                    _ => "Pending command... (Esc to cancel)"
+                }
+            } else {
+                "🎯 CURSOR-STYLE DEMO: Normal █ | Insert | | Visual blinking█\n\
+                Normal: hjkl/arrows=move, w/b/e=words, W/B/E=WORDS, 0/$=line, gg/G=first/last\n\
+                i/a/A/o/O=insert, v/V=visual, x/X=delete, ?=info\n\
+                F1=demo manual cursor, F2=restore automatic"
+            }
+        }
+        AppMode::Edit => {
+            "🎯 INSERT MODE - Cursor: | (bar)\n\
+             arrows=move, Ctrl+arrows=words, Backspace/Del=delete\n\
+             Esc=normal, Tab/Shift+Tab=fields"
+        }
+        AppMode::Highlight => {
+            "🎯 VISUAL MODE - Cursor: █ (blinking block)\n\
+             hjkl/arrows=extend selection, w/b/e=word selection\n\
+             Esc=normal"
+        }
+        _ => "🎯 Watch the cursor change automatically!"
+    };
+
+    let help = Paragraph::new(help_text)
+        .block(Block::default().borders(Borders::ALL).title("🚀 Automatic Cursor Management"))
+        .style(Style::default().fg(Color::Gray));
+
+    f.render_widget(help, chunks[1]);
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Print feature status
+    println!("🎯 Canvas Cursor Auto Demo");
+    println!("✅ cursor-style feature: ENABLED");
+    println!("🚀 Automatic cursor management: ACTIVE");
+    println!("📖 Watch your terminal cursor change based on mode!");
+    println!();
+
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    let data = CursorDemoData::new();
+    let mut editor = AutoCursorFormEditor::new(data);
+    
+    // Initialize with normal mode - library automatically sets block cursor
+    editor.set_mode(AppMode::ReadOnly);
+
+    // Demonstrate that CursorManager is available and working
+    CursorManager::update_for_mode(AppMode::ReadOnly)?;
+
+    let res = run_app(&mut terminal, editor);
+
+    // Library automatically resets cursor on FormEditor::drop()
+    // But we can also manually reset if needed
+    CursorManager::reset()?;
+
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err);
+    }
+
+    println!("🎯 Cursor automatically reset to default!");
+    Ok(())
+}
--- a/canvas/examples/canvas_gui_demo.rs
+++ b/canvas/examples/canvas_gui_demo.rs
@@ -1,388 +0,0 @@
-// examples/canvas_gui_demo.rs
-
-use std::io;
-use crossterm::{
-    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers},
-    execute,
-    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
-};
-use ratatui::{
-    backend::{Backend, CrosstermBackend},
-    layout::{Constraint, Direction, Layout},
-    style::{Color, Style},
-    text::{Line, Span},
-    widgets::{Block, Borders, Paragraph},
-    Frame, Terminal,
-};
-
-use canvas::{
-    canvas::{
-        gui::render_canvas,
-        modes::{AppMode, HighlightState, ModeManager},
-        state::{ActionContext, CanvasState},
-        theme::CanvasTheme,
-    },
-    CanvasAction, execute,
-};
-
-// Simple theme implementation
-#[derive(Clone)]
-struct DemoTheme;
-
-impl CanvasTheme for DemoTheme {
-    fn bg(&self) -> Color { Color::Reset }
-    fn fg(&self) -> Color { Color::White }
-    fn accent(&self) -> Color { Color::Cyan }
-    fn secondary(&self) -> Color { Color::Gray }
-    fn highlight(&self) -> Color { Color::Yellow }
-    fn highlight_bg(&self) -> Color { Color::DarkGray }
-    fn warning(&self) -> Color { Color::Red }
-    fn border(&self) -> Color { Color::Gray }
-}
-
-// Demo form state
-struct DemoFormState {
-    fields: Vec<String>,
-    field_names: Vec<String>,
-    current_field: usize,
-    cursor_pos: usize,
-    mode: AppMode,
-    highlight_state: HighlightState,
-    has_changes: bool,
-    debug_message: String,
-}
-
-impl DemoFormState {
-    fn new() -> Self {
-        Self {
-            fields: vec![
-                "John Doe".to_string(),
-                "john.doe@example.com".to_string(),
-                "+1 234 567 8900".to_string(),
-                "123 Main Street Apt 4B".to_string(),
-                "San Francisco".to_string(),
-                "This is a test comment with multiple words".to_string(),
-            ],
-            field_names: vec![
-                "Name".to_string(),
-                "Email".to_string(),
-                "Phone".to_string(),
-                "Address".to_string(),
-                "City".to_string(),
-                "Comments".to_string(),
-            ],
-            current_field: 0,
-            cursor_pos: 0,
-            mode: AppMode::ReadOnly,
-            highlight_state: HighlightState::Off,
-            has_changes: false,
-            debug_message: "Ready - Use hjkl to move, w for next word, i to edit".to_string(),
-        }
-    }
-
-    fn enter_edit_mode(&mut self) {
-        if ModeManager::can_enter_edit_mode(self.mode) {
-            self.mode = AppMode::Edit;
-            self.debug_message = "Entered EDIT mode".to_string();
-        }
-    }
-
-    fn enter_readonly_mode(&mut self) {
-        if ModeManager::can_enter_read_only_mode(self.mode) {
-            self.mode = AppMode::ReadOnly;
-            self.highlight_state = HighlightState::Off;
-            self.debug_message = "Entered READ-ONLY mode".to_string();
-        }
-    }
-
-    fn enter_highlight_mode(&mut self) {
-        if ModeManager::can_enter_highlight_mode(self.mode) {
-            self.mode = AppMode::Highlight;
-            self.highlight_state = HighlightState::Characterwise {
-                anchor: (self.current_field, self.cursor_pos),
-            };
-            self.debug_message = "Entered VISUAL mode".to_string();
-        }
-    }
-}
-
-impl CanvasState for DemoFormState {
-    fn current_field(&self) -> usize {
-        self.current_field
-    }
-
-    fn current_cursor_pos(&self) -> usize {
-        self.cursor_pos
-    }
-
-    fn set_current_field(&mut self, index: usize) {
-        self.current_field = index.min(self.fields.len().saturating_sub(1));
-        self.cursor_pos = self.fields[self.current_field].len();
-    }
-
-    fn set_current_cursor_pos(&mut self, pos: usize) {
-        let max_pos = self.fields[self.current_field].len();
-        self.cursor_pos = pos.min(max_pos);
-    }
-
-    fn current_mode(&self) -> AppMode {
-        self.mode
-    }
-
-    fn get_current_input(&self) -> &str {
-        &self.fields[self.current_field]
-    }
-
-    fn get_current_input_mut(&mut self) -> &mut String {
-        &mut self.fields[self.current_field]
-    }
-
-    fn inputs(&self) -> Vec<&String> {
-        self.fields.iter().collect()
-    }
-
-    fn fields(&self) -> Vec<&str> {
-        self.field_names.iter().map(|s| s.as_str()).collect()
-    }
-
-    fn has_unsaved_changes(&self) -> bool {
-        self.has_changes
-    }
-
-    fn set_has_unsaved_changes(&mut self, changed: bool) {
-        self.has_changes = changed;
-    }
-
-    fn handle_feature_action(&mut self, action: &CanvasAction, _context: &ActionContext) -> Option<String> {
-        match action {
-            CanvasAction::Custom(cmd) => {
-                match cmd.as_str() {
-                    "enter_edit_mode" => {
-                        self.enter_edit_mode();
-                        Some("Entered edit mode".to_string())
-                    }
-                    "enter_readonly_mode" => {
-                        self.enter_readonly_mode();
-                        Some("Entered read-only mode".to_string())
-                    }
-                    "enter_highlight_mode" => {
-                        self.enter_highlight_mode();
-                        Some("Entered highlight mode".to_string())
-                    }
-                    _ => None,
-                }
-            }
-            _ => None,
-        }
-    }
-}
-
-/// Simple key mapping - users have full control!
-async fn handle_key_press(key: KeyCode, modifiers: KeyModifiers, state: &mut DemoFormState) -> bool {
-    let is_edit_mode = state.mode == AppMode::Edit;
-    
-    // Handle quit first
-    if (key == KeyCode::Char('q') && modifiers.contains(KeyModifiers::CONTROL)) ||
-       (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL)) ||
-       key == KeyCode::F(10) {
-        return false; // Signal to quit
-    }
-
-    // Users directly map keys to actions - no configuration needed!
-    let action = match (state.mode, key, modifiers) {
-        // === READ-ONLY MODE KEYS ===
-        (AppMode::ReadOnly, KeyCode::Char('h'), _) => Some(CanvasAction::MoveLeft),
-        (AppMode::ReadOnly, KeyCode::Char('j'), _) => Some(CanvasAction::MoveDown),
-        (AppMode::ReadOnly, KeyCode::Char('k'), _) => Some(CanvasAction::MoveUp),
-        (AppMode::ReadOnly, KeyCode::Char('l'), _) => Some(CanvasAction::MoveRight),
-        (AppMode::ReadOnly, KeyCode::Char('w'), _) => Some(CanvasAction::MoveWordNext),
-        (AppMode::ReadOnly, KeyCode::Char('b'), _) => Some(CanvasAction::MoveWordPrev),
-        (AppMode::ReadOnly, KeyCode::Char('e'), _) => Some(CanvasAction::MoveWordEnd),
-        (AppMode::ReadOnly, KeyCode::Char('0'), _) => Some(CanvasAction::MoveLineStart),
-        (AppMode::ReadOnly, KeyCode::Char('$'), _) => Some(CanvasAction::MoveLineEnd),
-        (AppMode::ReadOnly, KeyCode::Tab, _) => Some(CanvasAction::NextField),
-        (AppMode::ReadOnly, KeyCode::BackTab, _) => Some(CanvasAction::PrevField),
-        
-        // === EDIT MODE KEYS ===
-        (AppMode::Edit, KeyCode::Left, _) => Some(CanvasAction::MoveLeft),
-        (AppMode::Edit, KeyCode::Right, _) => Some(CanvasAction::MoveRight),
-        (AppMode::Edit, KeyCode::Up, _) => Some(CanvasAction::MoveUp),
-        (AppMode::Edit, KeyCode::Down, _) => Some(CanvasAction::MoveDown),
-        (AppMode::Edit, KeyCode::Home, _) => Some(CanvasAction::MoveLineStart),
-        (AppMode::Edit, KeyCode::End, _) => Some(CanvasAction::MoveLineEnd),
-        (AppMode::Edit, KeyCode::Backspace, _) => Some(CanvasAction::DeleteBackward),
-        (AppMode::Edit, KeyCode::Delete, _) => Some(CanvasAction::DeleteForward),
-        (AppMode::Edit, KeyCode::Tab, _) => Some(CanvasAction::NextField),
-        (AppMode::Edit, KeyCode::BackTab, _) => Some(CanvasAction::PrevField),
-        
-        // Vim-style movement in edit mode (optional)
-        (AppMode::Edit, KeyCode::Char('h'), m) if m.contains(KeyModifiers::CONTROL) => Some(CanvasAction::MoveLeft),
-        (AppMode::Edit, KeyCode::Char('l'), m) if m.contains(KeyModifiers::CONTROL) => Some(CanvasAction::MoveRight),
-        
-        // Word movement with Ctrl in edit mode
-        (AppMode::Edit, KeyCode::Left, m) if m.contains(KeyModifiers::CONTROL) => Some(CanvasAction::MoveWordPrev),
-        (AppMode::Edit, KeyCode::Right, m) if m.contains(KeyModifiers::CONTROL) => Some(CanvasAction::MoveWordNext),
-        
-        // === MODE TRANSITIONS === 
-        (AppMode::ReadOnly, KeyCode::Char('i'), _) => Some(CanvasAction::Custom("enter_edit_mode".to_string())),
-        (AppMode::ReadOnly, KeyCode::Char('a'), _) => {
-            // 'a' moves to end of line then enters edit mode
-            if let Ok(_) = execute(CanvasAction::MoveLineEnd, state).await {
-                Some(CanvasAction::Custom("enter_edit_mode".to_string()))
-            } else {
-                None
-            }
-        },
-        (AppMode::ReadOnly, KeyCode::Char('v'), _) => Some(CanvasAction::Custom("enter_highlight_mode".to_string())),
-        (_, KeyCode::Esc, _) => Some(CanvasAction::Custom("enter_readonly_mode".to_string())),
-        
-        // === CHARACTER INPUT IN EDIT MODE ===
-        (AppMode::Edit, KeyCode::Char(c), m) if !m.contains(KeyModifiers::CONTROL) && !m.contains(KeyModifiers::ALT) => {
-            Some(CanvasAction::InsertChar(c))
-        },
-        
-        // === ARROW KEYS IN READ-ONLY MODE ===
-        (AppMode::ReadOnly, KeyCode::Left, _) => Some(CanvasAction::MoveLeft),
-        (AppMode::ReadOnly, KeyCode::Right, _) => Some(CanvasAction::MoveRight),
-        (AppMode::ReadOnly, KeyCode::Up, _) => Some(CanvasAction::MoveUp),
-        (AppMode::ReadOnly, KeyCode::Down, _) => Some(CanvasAction::MoveDown),
-        
-        _ => None,
-    };
-
-    // Execute the action if we found one
-    if let Some(action) = action {
-        match execute(action.clone(), state).await {
-            Ok(result) => {
-                if result.is_success() {
-                    // Mark as changed for editing actions
-                    if is_edit_mode {
-                        match action {
-                            CanvasAction::InsertChar(_) | CanvasAction::DeleteBackward | CanvasAction::DeleteForward => {
-                                state.set_has_unsaved_changes(true);
-                            }
-                            _ => {}
-                        }
-                    }
-                    
-                    if let Some(msg) = result.message() {
-                        state.debug_message = msg.to_string();
-                    } else {
-                        state.debug_message = format!("Executed: {}", action.description());
-                    }
-                } else if let Some(msg) = result.message() {
-                    state.debug_message = format!("Error: {}", msg);
-                }
-            }
-            Err(e) => {
-                state.debug_message = format!("Error executing action: {}", e);
-            }
-        }
-    } else {
-        state.debug_message = format!("Unhandled key: {:?} (mode: {:?})", key, state.mode);
-    }
-
-    true // Continue running
-}
-
-async fn run_app<B: Backend>(terminal: &mut Terminal<B>, mut state: DemoFormState) -> io::Result<()> {
-    let theme = DemoTheme;
-
-    loop {
-        terminal.draw(|f| ui(f, &state, &theme))?;
-
-        if let Event::Key(key) = event::read()? {
-            let should_continue = handle_key_press(key.code, key.modifiers, &mut state).await;
-            if !should_continue {
-                break;
-            }
-        }
-    }
-
-    Ok(())
-}
-
-fn ui(f: &mut Frame, state: &DemoFormState, theme: &DemoTheme) {
-    let chunks = Layout::default()
-        .direction(Direction::Vertical)
-        .constraints([
-            Constraint::Min(8),
-            Constraint::Length(4),
-        ])
-        .split(f.area());
-
-    // Render the canvas form
-    render_canvas(
-        f,
-        chunks[0],
-        state,
-        theme,
-        state.mode == AppMode::Edit,
-        &state.highlight_state,
-    );
-
-    // Render status bar
-    let mode_text = match state.mode {
-        AppMode::Edit => "EDIT",
-        AppMode::ReadOnly => "NORMAL",
-        AppMode::Highlight => "VISUAL",
-        AppMode::General => "GENERAL",
-        AppMode::Command => "COMMAND",
-    };
-
-    let status_text = if state.has_changes {
-        format!("-- {} -- [Modified]", mode_text)
-    } else {
-        format!("-- {} --", mode_text)
-    };
-
-    let position_text = format!("Field: {}/{} | Cursor: {} | Actions: {}", 
-        state.current_field + 1,
-        state.fields.len(),
-        state.cursor_pos,
-        CanvasAction::movement_actions().len() + CanvasAction::editing_actions().len());
-
-    let help_text = match state.mode {
-        AppMode::ReadOnly => "hjkl/arrows: Move | Tab/Shift+Tab: Fields | w/b/e: Words | 0/$: Line | i/a: Edit | v: Visual | F10: Quit",
-        AppMode::Edit => "Type to edit | Arrows/Ctrl+arrows: Move | Tab: Next field | Backspace/Delete: Delete | Home/End: Line | Esc: Normal | F10: Quit",
-        AppMode::Highlight => "hjkl/arrows: Select | w/b/e: Words | 0/$: Line | Esc: Normal | F10: Quit",
-        _ => "Esc: Normal | F10: Quit",
-    };
-
-    let status = Paragraph::new(vec![
-        Line::from(Span::styled(status_text, Style::default().fg(theme.accent()))),
-        Line::from(Span::styled(position_text, Style::default().fg(theme.fg()))),
-        Line::from(Span::styled(state.debug_message.clone(), Style::default().fg(theme.warning()))),
-        Line::from(Span::styled(help_text, Style::default().fg(theme.secondary()))),
-    ])
-    .block(Block::default().borders(Borders::ALL).title("Status"));
-
-    f.render_widget(status, chunks[1]);
-}
-
-#[tokio::main]
-async fn main() -> Result<(), Box<dyn std::error::Error>> {
-    enable_raw_mode()?;
-    let mut stdout = io::stdout();
-    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
-    let backend = CrosstermBackend::new(stdout);
-    let mut terminal = Terminal::new(backend)?;
-
-    let state = DemoFormState::new();
-
-    let res = run_app(&mut terminal, state).await;
-
-    disable_raw_mode()?;
-    execute!(
-        terminal.backend_mut(),
-        LeaveAlternateScreen,
-        DisableMouseCapture
-    )?;
-    terminal.show_cursor()?;
-
-    if let Err(err) = res {
-        println!("{:?}", err);
-    }
-
-    Ok(())
-}
--- a/canvas/examples/canvas_textarea_cursor_auto.rs
+++ b/canvas/examples/canvas_textarea_cursor_auto.rs
@@ -0,0 +1,652 @@
+// examples/canvas_textarea_cursor_auto.rs
+//! Demonstrates automatic cursor management with the textarea widget
+//!
+//! This example REQUIRES the `cursor-style` and `textarea` features to compile.
+//!
+//! Run with:
+//! cargo run --example canvas_textarea_cursor_auto --features "gui,cursor-style,textarea"
+
+// REQUIRE cursor-style and textarea features
+#[cfg(not(feature = "cursor-style"))]
+compile_error!(
+    "This example requires the 'cursor-style' feature. \
+     Run with: cargo run --example canvas_textarea_cursor_auto --features \"gui,cursor-style,textarea\""
+);
+
+#[cfg(not(feature = "textarea"))]
+compile_error!(
+    "This example requires the 'textarea' feature. \
+     Run with: cargo run --example canvas_textarea_cursor_auto --features \"gui,cursor-style,textarea\""
+);
+
+use std::io;
+use crossterm::{
+    event::{
+        self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyEvent, KeyModifiers,
+    },
+    execute,
+    terminal::{
+        disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen,
+    },
+};
+use ratatui::{
+    backend::{Backend, CrosstermBackend},
+    layout::{Constraint, Direction, Layout},
+    style::{Color, Style},
+    text::{Line, Span},
+    widgets::{Block, Borders, Paragraph},
+    Frame, Terminal,
+};
+
+use canvas::{
+    canvas::{
+        modes::AppMode,
+        CursorManager, // This import only exists when cursor-style feature is enabled
+    },
+    textarea::{TextArea, TextAreaState},
+};
+
+/// Enhanced TextArea that demonstrates automatic cursor management
+/// Now uses direct FormEditor method calls via Deref!
+struct AutoCursorTextArea {
+    textarea: TextAreaState,
+    has_unsaved_changes: bool,
+    debug_message: String,
+    command_buffer: String,
+}
+
+impl AutoCursorTextArea {
+    fn new() -> Self {
+        let initial_text = "🎯 Automatic Cursor Management Demo\n\
+Welcome to the textarea cursor demo!\n\
+\n\
+Try different modes:\n\
+• Normal mode: Block cursor █\n\
+• Insert mode: Bar cursor |\n\
+\n\
+Navigation commands:\n\
+• hjkl or arrow keys: move cursor\n\
+• i/a/A/o/O: enter insert mode\n\
+• w/b/e/W/B/E: word movements\n\
+• Esc: return to normal mode\n\
+\n\
+Watch how the terminal cursor changes automatically!\n\
+This text can be edited when in insert mode.\n\
+\n\
+Press ? for help, F1/F2 for manual cursor control demo.";
+
+        let mut textarea = TextAreaState::from_text(initial_text);
+        textarea.set_placeholder("Start typing...");
+        
+        Self {
+            textarea,
+            has_unsaved_changes: false,
+            debug_message: "🎯 Automatic Cursor Demo - cursor-style feature enabled!".to_string(),
+            command_buffer: String::new(),
+        }
+    }
+
+    // === MODE TRANSITIONS WITH AUTOMATIC CURSOR MANAGEMENT ===
+
+    fn enter_insert_mode(&mut self) -> std::io::Result<()> {
+        self.textarea.enter_edit_mode(); // 🎯 Direct FormEditor method call via Deref!
+        CursorManager::update_for_mode(AppMode::Edit)?; // 🎯 Automatic: cursor becomes bar |
+        self.debug_message = "✏️  INSERT MODE - Cursor: Steady Bar |".to_string();
+        Ok(())
+    }
+
+    fn enter_append_mode(&mut self) -> std::io::Result<()> {
+        self.textarea.enter_append_mode(); // 🎯 Direct FormEditor method call!
+        CursorManager::update_for_mode(AppMode::Edit)?;
+        self.debug_message = "✏️  INSERT (append) - Cursor: Steady Bar |".to_string();
+        Ok(())
+    }
+
+    fn exit_to_normal_mode(&mut self) -> std::io::Result<()> {
+        self.textarea.exit_edit_mode(); // 🎯 Direct FormEditor method call!
+        CursorManager::update_for_mode(AppMode::ReadOnly)?; // 🎯 Automatic: cursor becomes steady block
+        self.debug_message = "🔒 NORMAL MODE - Cursor: Steady Block █".to_string();
+        Ok(())
+    }
+
+    // === MANUAL CURSOR OVERRIDE DEMONSTRATION ===
+
+    fn demo_manual_cursor_control(&mut self) -> std::io::Result<()> {
+        // Users can still manually control cursor if needed
+        CursorManager::update_for_mode(AppMode::Command)?;
+        self.debug_message = "🔧 Manual override: Command cursor _".to_string();
+        Ok(())
+    }
+
+    fn restore_automatic_cursor(&mut self) -> std::io::Result<()> {
+        // Restore automatic cursor based on current mode
+        CursorManager::update_for_mode(self.textarea.mode())?; // 🎯 Direct method call!
+        self.debug_message = "🎯 Restored automatic cursor management".to_string();
+        Ok(())
+    }
+
+    // === TEXTAREA OPERATIONS ===
+
+    fn handle_textarea_input(&mut self, key: KeyEvent) {
+        self.textarea.input(key);
+        self.has_unsaved_changes = true;
+    }
+
+    // === MOVEMENT OPERATIONS (using direct FormEditor methods!) ===
+
+    fn move_left(&mut self) {
+        self.textarea.move_left(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("← left");
+    }
+
+    fn move_right(&mut self) {
+        self.textarea.move_right(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("→ right");
+    }
+
+    fn move_up(&mut self) {
+        self.textarea.move_up(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("↑ up");
+    }
+
+    fn move_down(&mut self) {
+        self.textarea.move_down(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("↓ down");
+    }
+
+    fn move_word_next(&mut self) {
+        self.textarea.move_word_next(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("w: next word");
+    }
+
+    fn move_word_prev(&mut self) {
+        self.textarea.move_word_prev(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("b: previous word");
+    }
+
+    fn move_word_end(&mut self) {
+        self.textarea.move_word_end(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("e: word end");
+    }
+
+    fn move_word_end_prev(&mut self) {
+        self.textarea.move_word_end_prev(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("ge: previous word end");
+    }
+
+    fn move_line_start(&mut self) {
+        self.textarea.move_line_start(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("0: line start");
+    }
+
+    fn move_line_end(&mut self) {
+        self.textarea.move_line_end(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("$: line end");
+    }
+
+    fn move_first_line(&mut self) {
+        self.textarea.move_first_line(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("gg: first line");
+    }
+
+    fn move_last_line(&mut self) {
+        self.textarea.move_last_line(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("G: last line");
+    }
+
+    // === BIG WORD MOVEMENTS ===
+
+    fn move_big_word_next(&mut self) {
+        self.textarea.move_big_word_next(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("W: next WORD");
+    }
+
+    fn move_big_word_prev(&mut self) {
+        self.textarea.move_big_word_prev(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("B: previous WORD");
+    }
+
+    fn move_big_word_end(&mut self) {
+        self.textarea.move_big_word_end(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("E: WORD end");
+    }
+
+    fn move_big_word_end_prev(&mut self) {
+        self.textarea.move_big_word_end_prev(); // 🎯 Direct FormEditor method call!
+        self.update_debug_for_movement("gE: previous WORD end");
+    }
+
+    fn update_debug_for_movement(&mut self, action: &str) {
+        self.debug_message = action.to_string();
+    }
+
+    // === DELETE OPERATIONS ===
+
+    fn delete_char_forward(&mut self) {
+        if let Ok(_) = self.textarea.delete_forward() { // 🎯 Direct FormEditor method call!
+            self.has_unsaved_changes = true;
+            self.debug_message = "x: deleted character".to_string();
+        }
+    }
+
+    fn delete_char_backward(&mut self) {
+        if let Ok(_) = self.textarea.delete_backward() { // 🎯 Direct FormEditor method call!
+            self.has_unsaved_changes = true;
+            self.debug_message = "X: deleted character backward".to_string();
+        }
+    }
+
+    // === VIM-STYLE EDITING ===
+
+    fn open_line_below(&mut self) -> anyhow::Result<()> {
+        let result = self.textarea.open_line_below(); // 🎯 Textarea-specific override!
+        if result.is_ok() {
+            CursorManager::update_for_mode(AppMode::Edit)?;
+            self.debug_message = "✏️  INSERT (open line below) - Cursor: Steady Bar |".to_string();
+            self.has_unsaved_changes = true;
+        }
+        result
+    }
+
+    fn open_line_above(&mut self) -> anyhow::Result<()> {
+        let result = self.textarea.open_line_above(); // 🎯 Textarea-specific override!
+        if result.is_ok() {
+            CursorManager::update_for_mode(AppMode::Edit)?;
+            self.debug_message = "✏️  INSERT (open line above) - Cursor: Steady Bar |".to_string();
+            self.has_unsaved_changes = true;
+        }
+        result
+    }
+
+    // === COMMAND BUFFER HANDLING ===
+
+    fn clear_command_buffer(&mut self) {
+        self.command_buffer.clear();
+    }
+
+    fn add_to_command_buffer(&mut self, ch: char) {
+        self.command_buffer.push(ch);
+    }
+
+    fn get_command_buffer(&self) -> &str {
+        &self.command_buffer
+    }
+
+    fn has_pending_command(&self) -> bool {
+        !self.command_buffer.is_empty()
+    }
+
+    // === GETTERS ===
+
+    fn mode(&self) -> AppMode {
+        self.textarea.mode() // 🎯 Direct FormEditor method call!
+    }
+
+    fn debug_message(&self) -> &str {
+        &self.debug_message
+    }
+
+    fn has_unsaved_changes(&self) -> bool {
+        self.has_unsaved_changes
+    }
+
+    fn set_debug_message(&mut self, msg: String) {
+        self.debug_message = msg;
+    }
+
+    fn get_cursor_info(&self) -> String {
+        format!(
+            "Line {}, Col {}",
+            self.textarea.current_field() + 1, // 🎯 Direct FormEditor method call!
+            self.textarea.cursor_position() + 1 // 🎯 Direct FormEditor method call!
+        )
+    }
+}
+
+/// Handle key press with automatic cursor management
+fn handle_key_press(
+    key_event: KeyEvent,
+    editor: &mut AutoCursorTextArea,
+) -> anyhow::Result<bool> {
+    let KeyEvent { code: key, modifiers, .. } = key_event;
+    let mode = editor.mode();
+
+    // Quit handling
+    if (key == KeyCode::Char('q') && modifiers.contains(KeyModifiers::CONTROL))
+        || (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL))
+        || key == KeyCode::F(10)
+    {
+        return Ok(false);
+    }
+
+    match (mode, key, modifiers) {
+        // === MODE TRANSITIONS WITH AUTOMATIC CURSOR MANAGEMENT ===
+        (AppMode::ReadOnly, KeyCode::Char('i'), _) => {
+            editor.enter_insert_mode()?;
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('a'), _) => {
+            editor.enter_append_mode()?;
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('A'), _) => {
+            editor.move_line_end();
+            editor.enter_insert_mode()?;
+            editor.clear_command_buffer();
+        }
+
+        // Vim o/O commands
+        (AppMode::ReadOnly, KeyCode::Char('o'), _) => {
+            if let Err(e) = editor.open_line_below() {
+                editor.set_debug_message(format!("Error opening line below: {}", e));
+            }
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('O'), _) => {
+            if let Err(e) = editor.open_line_above() {
+                editor.set_debug_message(format!("Error opening line above: {}", e));
+            }
+            editor.clear_command_buffer();
+        }
+
+        // Escape: Exit any mode back to normal
+        (AppMode::Edit, KeyCode::Esc, _) => {
+            editor.exit_to_normal_mode()?;
+        }
+
+        // === INSERT MODE: Pass to textarea ===
+        (AppMode::Edit, _, _) => {
+            editor.handle_textarea_input(key_event);
+        }
+
+        // === CURSOR MANAGEMENT DEMONSTRATION ===
+        (AppMode::ReadOnly, KeyCode::F(1), _) => {
+            editor.demo_manual_cursor_control()?;
+        }
+        (AppMode::ReadOnly, KeyCode::F(2), _) => {
+            editor.restore_automatic_cursor()?;
+        }
+
+        // === MOVEMENT: VIM-STYLE NAVIGATION (Normal mode) ===
+        (AppMode::ReadOnly, KeyCode::Char('h'), _)
+        | (AppMode::ReadOnly, KeyCode::Left, _) => {
+            editor.move_left();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('l'), _)
+        | (AppMode::ReadOnly, KeyCode::Right, _) => {
+            editor.move_right();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('j'), _)
+        | (AppMode::ReadOnly, KeyCode::Down, _) => {
+            editor.move_down();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('k'), _)
+        | (AppMode::ReadOnly, KeyCode::Up, _) => {
+            editor.move_up();
+            editor.clear_command_buffer();
+        }
+
+        // Word movement
+        (AppMode::ReadOnly, KeyCode::Char('w'), _) => {
+            editor.move_word_next();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('b'), _) => {
+            editor.move_word_prev();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('e'), _) => {
+            if editor.get_command_buffer() == "g" {
+                editor.move_word_end_prev();
+                editor.clear_command_buffer();
+            } else {
+                editor.move_word_end();
+                editor.clear_command_buffer();
+            }
+        }
+
+        // Big word movement (vim W/B/E commands)
+        (AppMode::ReadOnly, KeyCode::Char('W'), _) => {
+            editor.move_big_word_next();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('B'), _) => {
+            editor.move_big_word_prev();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('E'), _) => {
+            if editor.get_command_buffer() == "g" {
+                editor.move_big_word_end_prev();
+                editor.clear_command_buffer();
+            } else {
+                editor.move_big_word_end();
+                editor.clear_command_buffer();
+            }
+        }
+
+        // Line movement
+        (AppMode::ReadOnly, KeyCode::Char('0'), _)
+        | (AppMode::ReadOnly, KeyCode::Home, _) => {
+            editor.move_line_start();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('$'), _)
+        | (AppMode::ReadOnly, KeyCode::End, _) => {
+            editor.move_line_end();
+            editor.clear_command_buffer();
+        }
+
+        // Document movement with command buffer
+        (AppMode::ReadOnly, KeyCode::Char('g'), _) => {
+            if editor.get_command_buffer() == "g" {
+                editor.move_first_line();
+                editor.clear_command_buffer();
+            } else {
+                editor.clear_command_buffer();
+                editor.add_to_command_buffer('g');
+                editor.set_debug_message("g".to_string());
+            }
+        }
+        (AppMode::ReadOnly, KeyCode::Char('G'), _) => {
+            editor.move_last_line();
+            editor.clear_command_buffer();
+        }
+
+        // === DELETE OPERATIONS (Normal mode) ===
+        (AppMode::ReadOnly, KeyCode::Char('x'), _) => {
+            editor.delete_char_forward();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('X'), _) => {
+            editor.delete_char_backward();
+            editor.clear_command_buffer();
+        }
+
+        // === DEBUG/INFO COMMANDS ===
+        (AppMode::ReadOnly, KeyCode::Char('?'), _) => {
+            editor.set_debug_message(format!(
+                "{}, Mode: {:?} - Cursor managed automatically!",
+                editor.get_cursor_info(),
+                mode
+            ));
+            editor.clear_command_buffer();
+        }
+
+        _ => {
+            if editor.has_pending_command() {
+                editor.clear_command_buffer();
+                editor.set_debug_message("Invalid command sequence".to_string());
+            } else {
+                editor.set_debug_message(format!(
+                    "Unhandled: {:?} + {:?} in {:?} mode",
+                    key, modifiers, mode
+                ));
+            }
+        }
+    }
+
+    Ok(true)
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut editor: AutoCursorTextArea,
+) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f, &mut editor))?;
+
+        if let Event::Key(key) = event::read()? {
+            match handle_key_press(key, &mut editor) {
+                Ok(should_continue) => {
+                    if !should_continue {
+                        break;
+                    }
+                }
+                Err(e) => {
+                    editor.set_debug_message(format!("Error: {}", e));
+                }
+            }
+        }
+    }
+
+    Ok(())
+}
+
+fn ui(f: &mut Frame, editor: &mut AutoCursorTextArea) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Min(8), Constraint::Length(8)])
+        .split(f.area());
+
+    render_textarea(f, chunks[0], editor);
+    render_status_and_help(f, chunks[1], editor);
+}
+
+fn render_textarea(
+    f: &mut Frame,
+    area: ratatui::layout::Rect,
+    editor: &mut AutoCursorTextArea,
+) {
+    let block = Block::default()
+        .borders(Borders::ALL)
+        .title("🎯 Textarea with Automatic Cursor Management");
+
+    let textarea_widget = TextArea::default().block(block.clone());
+
+    f.render_stateful_widget(textarea_widget, area, &mut editor.textarea);
+
+    // Set cursor position for terminal cursor
+    // Always show cursor - CursorManager handles the style (block/bar/blinking)
+    let (cx, cy) = editor.textarea.cursor(area, Some(&block));
+    f.set_cursor_position((cx, cy));
+}
+
+fn render_status_and_help(
+    f: &mut Frame,
+    area: ratatui::layout::Rect,
+    editor: &AutoCursorTextArea,
+) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Length(3), Constraint::Length(5)])
+        .split(area);
+
+    // Status bar with cursor information
+    let mode_text = match editor.mode() {
+        AppMode::Edit => "INSERT | (bar cursor)",
+        AppMode::ReadOnly => "NORMAL █ (block cursor)",
+        AppMode::Highlight => "VISUAL █ (blinking block)",
+        _ => "NORMAL █ (block cursor)",
+    };
+
+    let status_text = if editor.has_pending_command() {
+        format!("-- {} -- {} [{}]", mode_text, editor.debug_message(), editor.get_command_buffer())
+    } else if editor.has_unsaved_changes() {
+        format!("-- {} -- [Modified] {} | {}", mode_text, editor.debug_message(), editor.get_cursor_info())
+    } else {
+        format!("-- {} -- {} | {}", mode_text, editor.debug_message(), editor.get_cursor_info())
+    };
+
+    let status = Paragraph::new(Line::from(Span::raw(status_text)))
+        .block(Block::default().borders(Borders::ALL).title("🎯 Automatic Cursor Status"));
+
+    f.render_widget(status, chunks[0]);
+
+    // Help text
+    let help_text = match editor.mode() {
+        AppMode::ReadOnly => {
+            if editor.has_pending_command() {
+                match editor.get_command_buffer() {
+                    "g" => "Press 'g' again for first line, or any other key to cancel",
+                    _ => "Pending command... (Esc to cancel)"
+                }
+            } else {
+                "🎯 CURSOR-STYLE DEMO: Normal █ | Insert | \n\
+                Normal: hjkl/arrows=move, w/b/e=words, W/B/E=WORDS, 0/$=line, g/G=first/last\n\
+                i/a/A/o/O=insert, x/X=delete, ?=info\n\
+                F1=demo manual cursor, F2=restore automatic, Ctrl+Q=quit"
+            }
+        }
+        AppMode::Edit => {
+            "🎯 INSERT MODE - Cursor: | (bar)\n\
+            Type to edit text, arrows=move, Enter=new line\n\
+            Esc=normal mode"
+        }
+        AppMode::Highlight => {
+            "🎯 VISUAL MODE - Cursor: █ (blinking block)\n\
+            hjkl/arrows=extend selection\n\
+            Esc=normal mode"
+        }
+        _ => "🎯 Watch the cursor change automatically!"
+    };
+
+    let help = Paragraph::new(help_text)
+        .block(Block::default().borders(Borders::ALL).title("🚀 Automatic Cursor Management"))
+        .style(Style::default().fg(Color::Gray));
+
+    f.render_widget(help, chunks[1]);
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Print feature status
+    println!("🎯 Canvas Textarea Cursor Auto Demo");
+    println!("✅ cursor-style feature: ENABLED");
+    println!("✅ textarea feature: ENABLED");
+    println!("🚀 Automatic cursor management: ACTIVE");
+    println!("📖 Watch your terminal cursor change based on mode!");
+    println!();
+
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    let mut editor = AutoCursorTextArea::new();
+
+    // Initialize with normal mode - library automatically sets block cursor
+    editor.exit_to_normal_mode()?;
+
+    let res = run_app(&mut terminal, editor);
+
+    // Reset cursor on exit
+    CursorManager::reset()?;
+
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err);
+    }
+
+    println!("🎯 Cursor automatically reset to default!");
+    Ok(())
+}
--- a/canvas/examples/computed_fields.rs
+++ b/canvas/examples/computed_fields.rs
@@ -0,0 +1,623 @@
+// examples/computed_fields.rs - COMPLETE WORKING VERSION
+//! Demonstrates computed fields with the canvas library - Invoice Calculator Example
+//!
+//! This example REQUIRES the `computed` feature to compile.
+//!
+//! Run with:
+//! cargo run --example computed_fields --features "gui,computed"
+
+#[cfg(not(feature = "computed"))]
+compile_error!(
+    "This example requires the 'computed' feature. \
+     Run with: cargo run --example computed_fields --features \"gui,computed\""
+);
+
+use std::io;
+use crossterm::{
+    event::{
+        self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers,
+    },
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use ratatui::{
+    backend::{Backend, CrosstermBackend},
+    layout::{Constraint, Direction, Layout, Rect},
+    style::{Color, Style, Modifier},
+    text::{Line, Span},
+    widgets::{Block, Borders, Paragraph, Wrap},
+    Frame, Terminal,
+};
+
+use canvas::{
+    canvas::{gui::render_canvas_default, modes::AppMode},
+    DataProvider, FormEditor,
+    computed::{ComputedProvider, ComputedContext},
+};
+
+/// Invoice data with computed fields
+struct InvoiceData {
+    fields: Vec<(String, String)>,
+    computed_indices: std::collections::HashSet<usize>,
+}
+
+impl InvoiceData {
+    fn new() -> Self {
+        let mut computed_indices = std::collections::HashSet::new();
+        
+        // Mark computed fields (read-only, calculated)
+        computed_indices.insert(4); // Subtotal
+        computed_indices.insert(5); // Tax Amount
+        computed_indices.insert(6); // Total
+
+        Self {
+            fields: vec![
+                ("📦 Product Name".to_string(), "".to_string()),
+                ("🔢 Quantity".to_string(), "".to_string()),
+                ("💰 Unit Price ($)".to_string(), "".to_string()),
+                ("📊 Tax Rate (%)".to_string(), "".to_string()),
+                ("➕ Subtotal ($)".to_string(), "".to_string()),        // COMPUTED
+                ("🧾 Tax Amount ($)".to_string(), "".to_string()),      // COMPUTED
+                ("💳 Total ($)".to_string(), "".to_string()),           // COMPUTED
+                ("📝 Notes".to_string(), "".to_string()),
+            ],
+            computed_indices,
+        }
+    }
+}
+
+impl DataProvider for InvoiceData {
+    fn field_count(&self) -> usize {
+        self.fields.len()
+    }
+
+    fn field_name(&self, index: usize) -> &str {
+        &self.fields[index].0
+    }
+
+    fn field_value(&self, index: usize) -> &str {
+        &self.fields[index].1
+    }
+
+    fn set_field_value(&mut self, index: usize, value: String) {
+        // 🔥 FIXED: Allow computed fields to be updated for display purposes
+        // The editing protection happens at the editor level, not here
+        self.fields[index].1 = value;
+    }
+
+    fn supports_suggestions(&self, _field_index: usize) -> bool {
+        false
+    }
+
+    fn display_value(&self, _index: usize) -> Option<&str> {
+        None
+    }
+    
+    /// Mark computed fields
+    fn is_computed_field(&self, field_index: usize) -> bool {
+        self.computed_indices.contains(&field_index)
+    }
+
+    /// Get computed field values
+    fn computed_field_value(&self, field_index: usize) -> Option<String> {
+        if self.computed_indices.contains(&field_index) {
+            Some(self.fields[field_index].1.clone())
+        } else {
+            None
+        }
+    }
+}
+
+/// Invoice calculator - computes totals based on input fields
+struct InvoiceCalculator;
+
+impl ComputedProvider for InvoiceCalculator {
+    fn compute_field(&mut self, context: ComputedContext) -> String {
+        // Helper to parse field values safely
+        let parse_field = |index: usize| -> f64 {
+            let value = context.field_values[index].trim();
+            if value.is_empty() {
+                0.0
+            } else {
+                value.parse().unwrap_or(0.0)
+            }
+        };
+
+        match context.target_field {
+            4 => {
+                // Subtotal = Quantity × Unit Price
+                let qty = parse_field(1);
+                let price = parse_field(2);
+                let subtotal = qty * price;
+                
+                if qty == 0.0 || price == 0.0 {
+                    "".to_string()  // Show empty if no meaningful calculation
+                } else {
+                    format!("{:.2}", subtotal)
+                }
+            }
+            5 => {
+                // Tax Amount = Subtotal × (Tax Rate / 100)
+                let qty = parse_field(1);
+                let price = parse_field(2);
+                let tax_rate = parse_field(3);
+                let subtotal = qty * price;
+                let tax_amount = subtotal * (tax_rate / 100.0);
+                
+                if subtotal == 0.0 || tax_rate == 0.0 {
+                    "".to_string()
+                } else {
+                    format!("{:.2}", tax_amount)
+                }
+            }
+            6 => {
+                // Total = Subtotal + Tax Amount
+                let qty = parse_field(1);
+                let price = parse_field(2);
+                let tax_rate = parse_field(3);
+                let subtotal = qty * price;
+                
+                if subtotal == 0.0 {
+                    "".to_string()
+                } else {
+                    let tax_amount = subtotal * (tax_rate / 100.0);
+                    let total = subtotal + tax_amount;
+                    format!("{:.2}", total)
+                }
+            }
+            _ => "".to_string(),
+        }
+    }
+    
+    fn handles_field(&self, field_index: usize) -> bool {
+        matches!(field_index, 4 | 5 | 6) // Subtotal, Tax Amount, Total
+    }
+    
+    fn field_dependencies(&self, field_index: usize) -> Vec<usize> {
+        match field_index {
+            4 => vec![1, 2],       // Subtotal depends on Quantity, Unit Price
+            5 => vec![1, 2, 3],    // Tax Amount depends on Quantity, Unit Price, Tax Rate
+            6 => vec![1, 2, 3],    // Total depends on Quantity, Unit Price, Tax Rate
+            _ => vec![],
+        }
+    }
+}
+
+/// Enhanced editor with computed fields
+struct ComputedFieldsEditor<D: DataProvider> {
+    editor: FormEditor<D>,
+    calculator: InvoiceCalculator,
+    debug_message: String,
+    last_computed_values: Vec<String>,
+}
+
+impl<D: DataProvider> ComputedFieldsEditor<D> {
+    fn new(data_provider: D) -> Self {
+        let mut editor = FormEditor::new(data_provider);
+        editor.set_computed_provider(InvoiceCalculator);
+
+        let calculator = InvoiceCalculator;
+        let last_computed_values = vec!["".to_string(); 8];
+
+        Self {
+            editor,
+            calculator,
+            debug_message: "💰 Invoice Calculator - Start typing in fields to see calculations!".to_string(),
+            last_computed_values,
+        }
+    }
+
+    fn is_computed_field(&self, field_index: usize) -> bool {
+        self.editor.ui_state().is_computed_field(field_index)
+    }
+
+    fn update_computed_fields(&mut self) {
+        // Trigger recomputation of all computed fields
+        self.editor.recompute_all_fields(&mut self.calculator);
+
+        // 🔥 CRITICAL FIX: Sync computed values to DataProvider so GUI shows them!
+        for i in [4, 5, 6] { // Computed field indices  
+            let computed_value = self.editor.effective_field_value(i);
+            self.editor.data_provider_mut().set_field_value(i, computed_value.clone());
+        }
+
+        // Check if values changed to show feedback
+        let mut changed = false;
+        let mut has_calculations = false;
+        
+        for i in [4, 5, 6] {
+            let new_value = self.editor.effective_field_value(i);
+            if new_value != self.last_computed_values[i] {
+                changed = true;
+                self.last_computed_values[i] = new_value.clone();
+            }
+            if !new_value.is_empty() {
+                has_calculations = true;
+            }
+        }
+
+        if changed {
+            if has_calculations {
+                let subtotal = &self.last_computed_values[4];
+                let tax = &self.last_computed_values[5];
+                let total = &self.last_computed_values[6];
+                
+                let mut parts = Vec::new();
+                if !subtotal.is_empty() {
+                    parts.push(format!("Subtotal=${}", subtotal));
+                }
+                if !tax.is_empty() {
+                    parts.push(format!("Tax=${}", tax));
+                }
+                if !total.is_empty() {
+                    parts.push(format!("Total=${}", total));
+                }
+                
+                if !parts.is_empty() {
+                    self.debug_message = format!("🧮 Calculated: {}", parts.join(", "));
+                } else {
+                    self.debug_message = "💰 Enter Quantity and Unit Price to see calculations".to_string();
+                }
+            } else {
+                self.debug_message = "💰 Enter Quantity and Unit Price to see calculations".to_string();
+            }
+        }
+    }
+
+    fn insert_char(&mut self, ch: char) -> anyhow::Result<()> {
+        let current_field = self.editor.current_field();
+        let result = self.editor.insert_char(ch);
+
+        if result.is_ok() && matches!(current_field, 1 | 2 | 3) {
+            self.editor.on_field_changed(&mut self.calculator, current_field);
+            self.update_computed_fields();
+        }
+
+        result
+    }
+
+    fn delete_backward(&mut self) -> anyhow::Result<()> {
+        let current_field = self.editor.current_field();
+        let result = self.editor.delete_backward();
+
+        if result.is_ok() && matches!(current_field, 1 | 2 | 3) {
+            self.editor.on_field_changed(&mut self.calculator, current_field);
+            self.update_computed_fields();
+        }
+
+        result
+    }
+
+    fn delete_forward(&mut self) -> anyhow::Result<()> {
+        let current_field = self.editor.current_field();
+        let result = self.editor.delete_forward();
+
+        if result.is_ok() && matches!(current_field, 1 | 2 | 3) {
+            self.editor.on_field_changed(&mut self.calculator, current_field);
+            self.update_computed_fields();
+        }
+
+        result
+    }
+
+    fn next_field(&mut self) {
+        let old_field = self.editor.current_field();
+        let _ = self.editor.next_field();
+        let new_field = self.editor.current_field();
+
+        if old_field != new_field {
+            let field_name = self.editor.data_provider().field_name(new_field);
+            let field_type = if self.is_computed_field(new_field) {
+                "computed (read-only)"
+            } else {
+                "editable"
+            };
+            self.debug_message = format!("→ {} - {} field", field_name, field_type);
+        }
+    }
+
+    fn prev_field(&mut self) {
+        let old_field = self.editor.current_field();
+        let _ = self.editor.prev_field();
+        let new_field = self.editor.current_field();
+
+        if old_field != new_field {
+            let field_name = self.editor.data_provider().field_name(new_field);
+            let field_type = if self.is_computed_field(new_field) {
+                "computed (read-only)"
+            } else {
+                "editable"
+            };
+            self.debug_message = format!("← {} - {} field", field_name, field_type);
+        }
+    }
+
+    fn enter_edit_mode(&mut self) {
+        let current = self.editor.current_field();
+        
+        // Double protection: check both ways
+        if self.editor.data_provider().is_computed_field(current) || self.is_computed_field(current) {
+            let field_name = self.editor.data_provider().field_name(current);
+            self.debug_message = format!(
+                "🚫 {} is computed (read-only) - Press Tab to move to editable fields",
+                field_name
+            );
+            return;
+        }
+        
+        self.editor.enter_edit_mode();
+        let field_name = self.editor.data_provider().field_name(current);
+        self.debug_message = format!("✏️ Editing {} - Type to see calculations update", field_name);
+    }
+
+    fn enter_append_mode(&mut self) {
+        let current = self.editor.current_field();
+        
+        if self.editor.data_provider().is_computed_field(current) || self.is_computed_field(current) {
+            let field_name = self.editor.data_provider().field_name(current);
+            self.debug_message = format!(
+                "🚫 {} is computed (read-only) - Press Tab to move to editable fields",
+                field_name
+            );
+            return;
+        }
+        
+        self.editor.enter_append_mode();
+        let field_name = self.editor.data_provider().field_name(current);
+        self.debug_message = format!("✏️ Appending to {} - Type to see calculations", field_name);
+    }
+
+    fn exit_edit_mode(&mut self) {
+        let current_field = self.editor.current_field();
+        self.editor.exit_edit_mode();
+
+        if matches!(current_field, 1 | 2 | 3) {
+            self.editor.on_field_changed(&mut self.calculator, current_field);
+            self.update_computed_fields();
+        }
+
+        self.debug_message = "🔒 Normal mode - Press 'i' to edit fields".to_string();
+    }
+
+    // Delegate methods
+    fn current_field(&self) -> usize { self.editor.current_field() }
+    fn cursor_position(&self) -> usize { self.editor.cursor_position() }
+    fn mode(&self) -> AppMode { self.editor.mode() }
+    fn current_text(&self) -> &str {
+        let field_index = self.editor.current_field();
+        self.editor.data_provider().field_value(field_index)
+    }
+    fn data_provider(&self) -> &D { self.editor.data_provider() }
+    fn ui_state(&self) -> &canvas::EditorState { self.editor.ui_state() }
+    fn move_left(&mut self) { self.editor.move_left(); }
+    fn move_right(&mut self) { self.editor.move_right(); }
+    fn move_up(&mut self) { let _ = self.editor.move_up(); }
+    fn move_down(&mut self) { let _ = self.editor.move_down(); }
+}
+
+fn handle_key_press(
+    key: KeyCode,
+    modifiers: KeyModifiers,
+    editor: &mut ComputedFieldsEditor<InvoiceData>,
+) -> anyhow::Result<bool> {
+    let mode = editor.mode();
+
+    if (key == KeyCode::Char('q') && modifiers.contains(KeyModifiers::CONTROL))
+        || (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL))
+        || key == KeyCode::F(10)
+    {
+        return Ok(false);
+    }
+
+    match (mode, key, modifiers) {
+        (AppMode::ReadOnly, KeyCode::Char('i'), _) => {
+            editor.enter_edit_mode();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('a'), _) => {
+            editor.enter_append_mode();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('A'), _) => {
+            editor.editor.move_line_end();
+            editor.enter_edit_mode();
+        }
+        (_, KeyCode::Esc, _) => {
+            if mode == AppMode::Edit {
+                editor.exit_edit_mode();
+            }
+        }
+
+        // Movement
+        (AppMode::ReadOnly, KeyCode::Char('h'), _) | (AppMode::ReadOnly, KeyCode::Left, _) => {
+            editor.move_left();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('l'), _) | (AppMode::ReadOnly, KeyCode::Right, _) => {
+            editor.move_right();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('j'), _) | (AppMode::ReadOnly, KeyCode::Down, _) => {
+            editor.move_down();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('k'), _) | (AppMode::ReadOnly, KeyCode::Up, _) => {
+            editor.move_up();
+        }
+
+        // Edit mode movement
+        (AppMode::Edit, KeyCode::Left, _) => { editor.move_left(); }
+        (AppMode::Edit, KeyCode::Right, _) => { editor.move_right(); }
+        (AppMode::Edit, KeyCode::Up, _) => { editor.move_up(); }
+        (AppMode::Edit, KeyCode::Down, _) => { editor.move_down(); }
+
+        // Navigation
+        (_, KeyCode::Tab, _) => {
+            editor.next_field();
+        }
+        (_, KeyCode::BackTab, _) => {
+            editor.prev_field();
+        }
+
+        // Editing
+        (AppMode::Edit, KeyCode::Char(c), m) if !m.contains(KeyModifiers::CONTROL) => {
+            editor.insert_char(c)?;
+        }
+        (AppMode::Edit, KeyCode::Backspace, _) => {
+            editor.delete_backward()?;
+        }
+        (AppMode::Edit, KeyCode::Delete, _) => {
+            editor.delete_forward()?;
+        }
+
+        // Debug info
+        (AppMode::ReadOnly, KeyCode::Char('?'), _) => {
+            let current = editor.current_field();
+            let field_name = editor.data_provider().field_name(current);
+            let field_type = if editor.is_computed_field(current) {
+                "COMPUTED (read-only)"
+            } else {
+                "EDITABLE"
+            };
+            editor.debug_message = format!(
+                "{} - {} - Position {} - Mode: {:?}",
+                field_name, field_type, editor.cursor_position(), mode
+            );
+        }
+
+        _ => {}
+    }
+
+    Ok(true)
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut editor: ComputedFieldsEditor<InvoiceData>,
+) -> io::Result<()> {
+    editor.update_computed_fields(); // Initial computation
+
+    loop {
+        terminal.draw(|f| ui(f, &editor))?;
+
+        if let Event::Key(key) = event::read()? {
+            match handle_key_press(key.code, key.modifiers, &mut editor) {
+                Ok(should_continue) => {
+                    if !should_continue {
+                        break;
+                    }
+                }
+                Err(e) => {
+                    editor.debug_message = format!("Error: {}", e);
+                }
+            }
+        }
+    }
+
+    Ok(())
+}
+
+fn ui(f: &mut Frame, editor: &ComputedFieldsEditor<InvoiceData>) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Min(8), Constraint::Length(10)])
+        .split(f.area());
+
+    render_enhanced_canvas(f, chunks[0], editor);
+    render_computed_status(f, chunks[1], editor);
+}
+
+fn render_enhanced_canvas(f: &mut Frame, area: Rect, editor: &ComputedFieldsEditor<InvoiceData>) {
+    render_canvas_default(f, area, &editor.editor);
+}
+
+fn render_computed_status(f: &mut Frame, area: Rect, editor: &ComputedFieldsEditor<InvoiceData>) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Length(3), Constraint::Length(7)])
+        .split(area);
+
+    let mode_text = match editor.mode() {
+        AppMode::Edit => "INSERT",
+        AppMode::ReadOnly => "NORMAL",
+        _ => "OTHER",
+    };
+
+    let current = editor.current_field();
+    let field_status = if editor.is_computed_field(current) {
+        "📊 COMPUTED FIELD (read-only)"
+    } else {
+        "✏️ EDITABLE FIELD"
+    };
+
+    let status_text = format!("-- {} -- {} | {}", mode_text, field_status, editor.debug_message);
+
+    let status = Paragraph::new(Line::from(Span::raw(status_text)))
+        .block(Block::default().borders(Borders::ALL).title("💰 Invoice Calculator"));
+
+    f.render_widget(status, chunks[0]);
+
+    let help_text = match editor.mode() {
+        AppMode::ReadOnly => {
+            "💰 COMPUTED FIELDS DEMO: Real-time invoice calculations!\n\
+             🔢 EDITABLE: Product, Quantity, Unit Price, Tax Rate, Notes\n\
+             📊 COMPUTED: Subtotal, Tax Amount, Total (calculated automatically)\n\
+             \n\
+             🚀 START: Press 'i' to edit Quantity, type '5', Tab to Unit Price, type '19.99'\n\
+             Watch Subtotal and Total appear! Add Tax Rate to see tax calculations.\n\
+             Navigation: Tab/Shift+Tab skips computed fields automatically"
+        }
+        AppMode::Edit => {
+            "✏️ EDIT MODE: Type numbers to see calculations appear!\n\
+             \n\
+             💡 EXAMPLE: Type '5' in Quantity, then Tab to Unit Price and type '19.99'\n\
+             • Subtotal appears: $99.95\n\
+             • Total appears: $99.95\n\
+             • Add Tax Rate (like '10') to see tax: $9.99, Total: $109.94\n\
+             \n\
+             Esc=normal, Tab=next field (auto-skips computed fields)"
+        }
+        _ => "💰 Invoice Calculator with Computed Fields"
+    };
+
+    let help_style = if editor.is_computed_field(editor.current_field()) {
+        Style::default().fg(Color::Yellow).add_modifier(Modifier::ITALIC)
+    } else {
+        Style::default().fg(Color::Gray)
+    };
+
+    let help = Paragraph::new(help_text)
+        .block(Block::default().borders(Borders::ALL).title("🚀 Try It Now!"))
+        .style(help_style)
+        .wrap(Wrap { trim: true });
+
+    f.render_widget(help, chunks[1]);
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    println!("💰 Canvas Computed Fields Demo - Invoice Calculator");
+    println!("✅ computed feature: ENABLED");
+    println!("🚀 QUICK TEST:");
+    println!("   1. Press 'i' to edit Quantity");
+    println!("   2. Type '5' and press Tab");
+    println!("   3. Type '19.99' in Unit Price");
+    println!("   4. Watch Subtotal ($99.95) and Total ($99.95) appear!");
+    println!();
+
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    let data = InvoiceData::new();
+    let editor = ComputedFieldsEditor::new(data);
+
+    let res = run_app(&mut terminal, editor);
+
+    disable_raw_mode()?;
+    execute!(terminal.backend_mut(), LeaveAlternateScreen, DisableMouseCapture)?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err);
+    }
+
+    println!("💰 Demo completed! Computed fields should have updated in real-time!");
+    Ok(())
+}
--- a/canvas/examples/full_canvas_demo.rs
+++ b/canvas/examples/full_canvas_demo.rs
@@ -0,0 +1,724 @@
+// examples/full_canvas_demo.rs
+//! Demonstrates the FULL potential of the canvas library using the native API
+
+use std::io;
+use crossterm::{
+    cursor::SetCursorStyle,
+    event::{
+        self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers,
+    },
+    execute,
+    terminal::{
+        disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen,
+    },
+};
+use ratatui::{
+    backend::{Backend, CrosstermBackend},
+    layout::{Constraint, Direction, Layout},
+    style::{Color, Style},
+    text::{Line, Span},
+    widgets::{Block, Borders, Paragraph},
+    Frame, Terminal,
+};
+
+use canvas::{
+    canvas::{
+        gui::render_canvas_default,
+        modes::{AppMode, ModeManager, HighlightState},
+    },
+    DataProvider, FormEditor,
+};
+
+/// Update cursor style based on current AppMode
+fn update_cursor_for_mode(mode: AppMode) -> io::Result<()> {
+    let style = match mode {
+        AppMode::Edit => SetCursorStyle::SteadyBar,           // Thin line for insert mode
+        AppMode::ReadOnly => SetCursorStyle::SteadyBlock,     // Block for normal mode  
+        AppMode::Highlight => SetCursorStyle::BlinkingBlock,  // Blinking block for visual mode
+        AppMode::General => SetCursorStyle::SteadyBlock,      // Block for general mode
+        AppMode::Command => SetCursorStyle::SteadyUnderScore, // Underscore for command mode
+    };
+    
+    execute!(io::stdout(), style)
+}
+
+// Enhanced FormEditor that adds visual mode and status tracking
+struct EnhancedFormEditor<D: DataProvider> {
+    editor: FormEditor<D>,
+    highlight_state: HighlightState,
+    has_unsaved_changes: bool,
+    debug_message: String,
+    command_buffer: String, // For multi-key vim commands like "gg"
+}
+
+impl<D: DataProvider> EnhancedFormEditor<D> {
+    fn new(data_provider: D) -> Self {
+        Self {
+            editor: FormEditor::new(data_provider),
+            highlight_state: HighlightState::Off,
+            has_unsaved_changes: false,
+            debug_message: "Full Canvas Demo - All features enabled".to_string(),
+            command_buffer: String::new(),
+        }
+    }
+
+    // === COMMAND BUFFER HANDLING ===
+
+    fn clear_command_buffer(&mut self) {
+        self.command_buffer.clear();
+    }
+
+    fn add_to_command_buffer(&mut self, ch: char) {
+        self.command_buffer.push(ch);
+    }
+
+    fn get_command_buffer(&self) -> &str {
+        &self.command_buffer
+    }
+
+    fn has_pending_command(&self) -> bool {
+        !self.command_buffer.is_empty()
+    }
+
+    // === VISUAL/HIGHLIGHT MODE SUPPORT ===
+
+    fn enter_visual_mode(&mut self) {
+        if ModeManager::can_enter_highlight_mode(self.editor.mode()) {
+            self.editor.set_mode(AppMode::Highlight);
+            self.highlight_state = HighlightState::Characterwise {
+                anchor: (
+                    self.editor.current_field(),
+                    self.editor.cursor_position(),
+                ),
+            };
+            self.debug_message = "-- VISUAL --".to_string();
+        }
+    }
+
+    fn enter_visual_line_mode(&mut self) {
+        if ModeManager::can_enter_highlight_mode(self.editor.mode()) {
+            self.editor.set_mode(AppMode::Highlight);
+            self.highlight_state =
+                HighlightState::Linewise { anchor_line: self.editor.current_field() };
+            self.debug_message = "-- VISUAL LINE --".to_string();
+        }
+    }
+
+    fn exit_visual_mode(&mut self) {
+        self.highlight_state = HighlightState::Off;
+        if self.editor.mode() == AppMode::Highlight {
+            self.editor.set_mode(AppMode::ReadOnly);
+            self.debug_message = "Visual mode exited".to_string();
+        }
+    }
+
+    fn update_visual_selection(&mut self) {
+        if self.editor.mode() == AppMode::Highlight {
+            match &self.highlight_state {
+                HighlightState::Characterwise { anchor: _ } => {
+                    self.debug_message = format!(
+                        "Visual selection: char {} in field {}",
+                        self.editor.cursor_position(),
+                        self.editor.current_field()
+                    );
+                }
+                HighlightState::Linewise { anchor_line: _ } => {
+                    self.debug_message = format!(
+                        "Visual line selection: field {}",
+                        self.editor.current_field()
+                    );
+                }
+                _ => {}
+            }
+        }
+    }
+
+    // === ENHANCED MOVEMENT WITH VISUAL UPDATES ===
+
+    fn move_left(&mut self) {
+        self.editor.move_left();
+        self.update_visual_selection();
+    }
+
+    fn move_right(&mut self) {
+        self.editor.move_right();
+        self.update_visual_selection();
+    }
+
+    fn move_up(&mut self) {
+        self.editor.move_up();
+        self.update_visual_selection();
+    }
+
+    fn move_down(&mut self) {
+        self.editor.move_down();
+        self.update_visual_selection();
+    }
+
+    fn move_word_next(&mut self) {
+        self.editor.move_word_next();
+        self.update_visual_selection();
+    }
+
+    fn move_word_prev(&mut self) {
+        self.editor.move_word_prev();
+        self.update_visual_selection();
+    }
+
+    fn move_word_end(&mut self) {
+        self.editor.move_word_end();
+        self.update_visual_selection();
+    }
+
+    fn move_word_end_prev(&mut self) {
+        self.editor.move_word_end_prev();
+        self.update_visual_selection();
+    }
+
+    fn move_line_start(&mut self) {
+        self.editor.move_line_start();
+        self.update_visual_selection();
+    }
+
+    fn move_line_end(&mut self) {
+        self.editor.move_line_end();
+        self.update_visual_selection();
+    }
+
+    fn move_first_line(&mut self) {
+        self.editor.move_first_line();
+        self.update_visual_selection();
+    }
+
+    fn move_last_line(&mut self) {
+        self.editor.move_last_line();
+        self.update_visual_selection();
+    }
+
+    fn prev_field(&mut self) {
+        self.editor.prev_field();
+        self.update_visual_selection();
+    }
+
+    fn next_field(&mut self) {
+        self.editor.next_field();
+        self.update_visual_selection();
+    }
+
+    // === DELETE OPERATIONS ===
+
+    fn delete_backward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_backward();
+        if result.is_ok() {
+            self.has_unsaved_changes = true;
+            self.debug_message = "Deleted character backward".to_string();
+        }
+        Ok(result?)
+    }
+
+    fn delete_forward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_forward();
+        if result.is_ok() {
+            self.has_unsaved_changes = true;
+            self.debug_message = "Deleted character forward".to_string();
+        }
+        Ok(result?)
+    }
+
+    // === MODE TRANSITIONS ===
+
+    fn enter_edit_mode(&mut self) {
+        self.editor.enter_edit_mode();
+        self.debug_message = "-- INSERT --".to_string();
+    }
+
+    fn exit_edit_mode(&mut self) {
+        self.editor.exit_edit_mode();
+        self.exit_visual_mode();
+        self.debug_message = "".to_string();
+    }
+
+    fn insert_char(&mut self, ch: char) -> anyhow::Result<()> {
+        let result = self.editor.insert_char(ch);
+        if result.is_ok() {
+            self.has_unsaved_changes = true;
+        }
+        Ok(result?)
+    }
+
+    // === DELEGATE TO ORIGINAL EDITOR ===
+
+    fn current_field(&self) -> usize {
+        self.editor.current_field()
+    }
+
+    fn cursor_position(&self) -> usize {
+        self.editor.cursor_position()
+    }
+
+    fn mode(&self) -> AppMode {
+        self.editor.mode()
+    }
+
+    fn current_text(&self) -> &str {
+        self.editor.current_text()
+    }
+
+    fn data_provider(&self) -> &D {
+        self.editor.data_provider()
+    }
+
+    fn ui_state(&self) -> &canvas::EditorState {
+        self.editor.ui_state()
+    }
+
+    fn set_mode(&mut self, mode: AppMode) {
+        self.editor.set_mode(mode);
+        if mode != AppMode::Highlight {
+            self.exit_visual_mode();
+        }
+    }
+
+    // === STATUS AND DEBUG ===
+
+    fn set_debug_message(&mut self, msg: String) {
+        self.debug_message = msg;
+    }
+
+    fn debug_message(&self) -> &str {
+        &self.debug_message
+    }
+
+    fn highlight_state(&self) -> &HighlightState {
+        &self.highlight_state
+    }
+
+    fn has_unsaved_changes(&self) -> bool {
+        self.has_unsaved_changes
+    }
+}
+
+// Demo form data with interesting text for word movement
+struct FullDemoData {
+    fields: Vec<(String, String)>,
+}
+
+impl FullDemoData {
+    fn new() -> Self {
+        Self {
+            fields: vec![
+                ("Name".to_string(), "John-Paul McDonald".to_string()),
+                (
+                    "Email".to_string(),
+                    "user@example-domain.com".to_string(),
+                ),
+                ("Phone".to_string(), "+1 (555) 123-4567".to_string()),
+                ("Address".to_string(), "123 Main St, Apt 4B".to_string()),
+                (
+                    "Tags".to_string(),
+                    "urgent,important,follow-up".to_string(),
+                ),
+                (
+                    "Notes".to_string(),
+                    "This is a sample note with multiple words, punctuation! And symbols @#$"
+                        .to_string(),
+                ),
+            ],
+        }
+    }
+}
+
+impl DataProvider for FullDemoData {
+    fn field_count(&self) -> usize {
+        self.fields.len()
+    }
+
+    fn field_name(&self, index: usize) -> &str {
+        &self.fields[index].0
+    }
+
+    fn field_value(&self, index: usize) -> &str {
+        &self.fields[index].1
+    }
+
+    fn set_field_value(&mut self, index: usize, value: String) {
+        self.fields[index].1 = value;
+    }
+
+    fn supports_suggestions(&self, _field_index: usize) -> bool {
+        false
+    }
+
+    fn display_value(&self, _index: usize) -> Option<&str> {
+        None
+    }
+}
+
+/// Full vim-like key handling using the native FormEditor API
+fn handle_key_press(
+    key: KeyCode,
+    modifiers: KeyModifiers,
+    editor: &mut EnhancedFormEditor<FullDemoData>,
+) -> anyhow::Result<bool> {
+    let old_mode = editor.mode(); // Store mode before processing
+
+    // Quit handling
+    if (key == KeyCode::Char('q') && modifiers.contains(KeyModifiers::CONTROL))
+        || (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL))
+        || key == KeyCode::F(10)
+    {
+        return Ok(false);
+    }
+
+    match (old_mode, key, modifiers) {
+        // === MODE TRANSITIONS ===
+        (AppMode::ReadOnly, KeyCode::Char('i'), _) => {
+            editor.enter_edit_mode();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('a'), _) => {
+            editor.move_right(); // Move after current character
+            editor.enter_edit_mode();
+            editor.set_debug_message("-- INSERT -- (append)".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('A'), _) => {
+            editor.move_line_end();
+            editor.enter_edit_mode();
+            editor.set_debug_message("-- INSERT -- (end of line)".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('o'), _) => {
+            editor.move_line_end();
+            editor.enter_edit_mode();
+            editor.set_debug_message("-- INSERT -- (open line)".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('v'), _) => {
+            editor.enter_visual_mode();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('V'), _) => {
+            editor.enter_visual_line_mode();
+            editor.clear_command_buffer();
+        }
+        (_, KeyCode::Esc, _) => {
+            editor.exit_edit_mode();
+            editor.clear_command_buffer();
+        }
+
+        // === MOVEMENT: VIM-STYLE NAVIGATION ===
+
+        // Basic movement (hjkl and arrows)
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('h'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Left, _) => {
+            editor.move_left();
+            editor.set_debug_message("← left".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('l'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Right, _) => {
+            editor.move_right();
+            editor.set_debug_message("→ right".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('j'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Down, _) => {
+            editor.move_down();
+            editor.set_debug_message("↓ next field".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('k'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Up, _) => {
+            editor.move_up();
+            editor.set_debug_message("↑ previous field".to_string());
+            editor.clear_command_buffer();
+        }
+
+        // Word movement - Full vim word navigation
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('w'), _) => {
+            editor.move_word_next();
+            editor.set_debug_message("w: next word start".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('b'), _) => {
+            editor.move_word_prev();
+            editor.set_debug_message("b: previous word start".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('e'), _) => {
+            editor.move_word_end();
+            editor.set_debug_message("e: word end".to_string());
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('W'), _) => {
+            editor.move_word_end_prev();
+            editor.set_debug_message("W: previous word end".to_string());
+            editor.clear_command_buffer();
+        }
+
+        // Line movement
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('0'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Home, _) => {
+            editor.move_line_start();
+            editor.set_debug_message("0: line start".to_string());
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('$'), _)
+        | (AppMode::ReadOnly | AppMode::Highlight, KeyCode::End, _) => {
+            editor.move_line_end();
+            editor.set_debug_message("$: line end".to_string());
+        }
+
+        // Field/document movement
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('g'), _) => {
+            if editor.get_command_buffer() == "g" {
+                // Second 'g' - execute "gg" command
+                editor.move_first_line();
+                editor.set_debug_message("gg: first field".to_string());
+                editor.clear_command_buffer();
+            } else {
+                // First 'g' - start command buffer
+                editor.clear_command_buffer();
+                editor.add_to_command_buffer('g');
+                editor.set_debug_message("g".to_string());
+            }
+        }
+        (AppMode::ReadOnly | AppMode::Highlight, KeyCode::Char('G'), _) => {
+            editor.move_last_line();
+            editor.set_debug_message("G: last field".to_string());
+            editor.clear_command_buffer();
+        }
+
+        // === EDIT MODE MOVEMENT ===
+        (AppMode::Edit, KeyCode::Left, m) if m.contains(KeyModifiers::CONTROL) => {
+            editor.move_word_prev();
+            editor.set_debug_message("Ctrl+← word back".to_string());
+        }
+        (AppMode::Edit, KeyCode::Right, m) if m.contains(KeyModifiers::CONTROL) => {
+            editor.move_word_next();
+            editor.set_debug_message("Ctrl+→ word forward".to_string());
+        }
+        (AppMode::Edit, KeyCode::Left, _) => {
+            editor.move_left();
+        }
+        (AppMode::Edit, KeyCode::Right, _) => {
+            editor.move_right();
+        }
+        (AppMode::Edit, KeyCode::Up, _) => {
+            editor.move_up();
+        }
+        (AppMode::Edit, KeyCode::Down, _) => {
+            editor.move_down();
+        }
+        (AppMode::Edit, KeyCode::Home, _) => {
+            editor.move_line_start();
+        }
+        (AppMode::Edit, KeyCode::End, _) => {
+            editor.move_line_end();
+        }
+
+        // === DELETE OPERATIONS ===
+        (AppMode::Edit, KeyCode::Backspace, _) => {
+            editor.delete_backward()?;
+        }
+        (AppMode::Edit, KeyCode::Delete, _) => {
+            editor.delete_forward()?;
+        }
+
+        // Delete operations in normal mode (vim x)
+        (AppMode::ReadOnly, KeyCode::Char('x'), _) => {
+            editor.delete_forward()?;
+            editor.set_debug_message("x: deleted character".to_string());
+        }
+        (AppMode::ReadOnly, KeyCode::Char('X'), _) => {
+            editor.delete_backward()?;
+            editor.set_debug_message("X: deleted character backward".to_string());
+        }
+
+        // === TAB NAVIGATION ===
+        (_, KeyCode::Tab, _) => {
+            editor.next_field();
+            editor.set_debug_message("Tab: next field".to_string());
+        }
+        (_, KeyCode::BackTab, _) => {
+            editor.prev_field();
+            editor.set_debug_message("Shift+Tab: previous field".to_string());
+        }
+
+        // === CHARACTER INPUT ===
+        (AppMode::Edit, KeyCode::Char(c), m) if !m.contains(KeyModifiers::CONTROL) => {
+            editor.insert_char(c)?;
+        }
+
+        // === DEBUG/INFO COMMANDS ===
+        (AppMode::ReadOnly, KeyCode::Char('?'), _) => {
+            editor.set_debug_message(format!(
+                "Field {}/{}, Pos {}, Mode: {:?}",
+                editor.current_field() + 1,
+                editor.data_provider().field_count(),
+                editor.cursor_position(),
+                editor.mode()
+            ));
+        }
+
+        _ => {
+            // If we have a pending command and this key doesn't complete it, clear the buffer
+            if editor.has_pending_command() {
+                editor.clear_command_buffer();
+                editor.set_debug_message("Invalid command sequence".to_string());
+            } else {
+                editor.set_debug_message(format!(
+                    "Unhandled: {:?} + {:?} in {:?} mode",
+                    key, modifiers, old_mode
+                ));
+            }
+        }
+    }
+
+    // Update cursor if mode changed
+    let new_mode = editor.mode();
+    if old_mode != new_mode {
+        update_cursor_for_mode(new_mode)?;
+    }
+
+    Ok(true)
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut editor: EnhancedFormEditor<FullDemoData>,
+) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f, &editor))?;
+
+        if let Event::Key(key) = event::read()? {
+            match handle_key_press(key.code, key.modifiers, &mut editor) {
+                Ok(should_continue) => {
+                    if !should_continue {
+                        break;
+                    }
+                }
+                Err(e) => {
+                    editor.set_debug_message(format!("Error: {}", e));
+                }
+            }
+        }
+    }
+
+    Ok(())
+}
+
+fn ui(f: &mut Frame, editor: &EnhancedFormEditor<FullDemoData>) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Min(8), Constraint::Length(8)])
+        .split(f.area());
+
+    render_enhanced_canvas(f, chunks[0], editor);
+    render_status_and_help(f, chunks[1], editor);
+}
+
+fn render_enhanced_canvas(
+    f: &mut Frame,
+    area: ratatui::layout::Rect,
+    editor: &EnhancedFormEditor<FullDemoData>,
+) {
+    render_canvas_default(f, area, &editor.editor);
+}
+
+fn render_status_and_help(
+    f: &mut Frame,
+    area: ratatui::layout::Rect,
+    editor: &EnhancedFormEditor<FullDemoData>,
+) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Length(3), Constraint::Length(5)])
+        .split(area);
+
+    // Status bar
+    let mode_text = match editor.mode() {
+        AppMode::Edit => "INSERT",
+        AppMode::ReadOnly => "NORMAL",
+        AppMode::Highlight => match editor.highlight_state() {
+            HighlightState::Characterwise { .. } => "VISUAL",
+            HighlightState::Linewise { .. } => "VISUAL LINE",
+            _ => "VISUAL",
+        },
+        _ => "NORMAL",
+    };
+
+    let status_text = if editor.has_pending_command() {
+        format!("-- {} -- {} [{}]", mode_text, editor.debug_message(), editor.get_command_buffer())
+    } else if editor.has_unsaved_changes() {
+        format!("-- {} -- [Modified] {}", mode_text, editor.debug_message())
+    } else {
+        format!("-- {} -- {}", mode_text, editor.debug_message())
+    };
+
+    let status = Paragraph::new(Line::from(Span::raw(status_text)))
+        .block(Block::default().borders(Borders::ALL).title("Status"));
+
+    f.render_widget(status, chunks[0]);
+
+    // Help text
+    let help_text = match editor.mode() {
+        AppMode::ReadOnly => {
+            if editor.has_pending_command() {
+                match editor.get_command_buffer() {
+                    "g" => "Press 'g' again for first field, or any other key to cancel",
+                    _ => "Pending command... (Esc to cancel)"
+                }
+            } else {
+                "Normal: hjkl/arrows=move, w/b/e=words, 0/$=line, gg/G=first/last, i/a/A=insert, v/V=visual, x/X=delete, ?=info"
+            }
+        }
+        AppMode::Edit => {
+            "Insert: arrows=move, Ctrl+arrows=words, Backspace/Del=delete, Esc=normal, Tab/Shift+Tab=fields"
+        }
+        AppMode::Highlight => {
+            "Visual: hjkl/arrows=extend selection, w/b/e=word selection, Esc=normal"
+        }
+        _ => "Press ? for help"
+    };
+
+    let help = Paragraph::new(Line::from(Span::raw(help_text)))
+        .block(Block::default().borders(Borders::ALL).title("Commands"))
+        .style(Style::default().fg(Color::Gray));
+
+    f.render_widget(help, chunks[1]);
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    let data = FullDemoData::new();
+    let mut editor = EnhancedFormEditor::new(data);
+    editor.set_mode(AppMode::ReadOnly); // Start in normal mode
+    
+    // Set initial cursor style
+    update_cursor_for_mode(editor.mode())?;
+
+    let res = run_app(&mut terminal, editor);
+
+    // Reset cursor style on exit
+    execute!(io::stdout(), SetCursorStyle::DefaultUserShape)?;
+
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err);
+    }
+
+    Ok(())
+}
--- a/canvas/examples/suggestions.rs
+++ b/canvas/examples/suggestions.rs
--- a/canvas/examples/suggestions2.rs
+++ b/canvas/examples/suggestions2.rs
--- a/canvas/examples/validation_1.rs
+++ b/canvas/examples/validation_1.rs
@@ -0,0 +1,831 @@
+// examples/validation_1.rs
+//! Demonstrates field validation with the canvas library
+//!
+//! This example REQUIRES the `validation` and `cursor-style` features to compile.
+//!
+//! Run with:
+//! cargo run --example validation_1 --features "gui,validation"
+//!
+//! This will fail without validation:
+//! cargo run --example validation_1 --features "gui"
+
+// REQUIRE validation feature - example won't compile without it
+#[cfg(not(all(feature = "validation", feature = "cursor-style")))]
+compile_error!(
+    "This example requires the 'validation' and 'cursor-style' features. \
+     Run with: cargo run --example validation_1 --features \"gui,validation,cursor-style\""
+);
+
+use std::io;
+use crossterm::{
+    event::{
+        self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers,
+    },
+    execute,
+    terminal::{
+        disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen,
+    },
+};
+use ratatui::{
+    backend::{Backend, CrosstermBackend},
+    layout::{Constraint, Direction, Layout, Rect},
+    style::{Color, Style},
+    text::{Line, Span},
+    widgets::{Block, Borders, Paragraph, Wrap},
+    Frame, Terminal,
+};
+use canvas::{
+    canvas::{
+        gui::render_canvas_default,
+        modes::AppMode,
+        CursorManager,
+    },
+    DataProvider, FormEditor,
+    ValidationConfig, ValidationConfigBuilder, CharacterLimits, ValidationResult,
+};
+
+// Import CountMode from the validation module directly
+use canvas::validation::limits::CountMode;
+
+// Enhanced FormEditor that demonstrates validation functionality
+struct ValidationFormEditor<D: DataProvider> {
+    editor: FormEditor<D>,
+    has_unsaved_changes: bool,
+    debug_message: String,
+    command_buffer: String,
+    validation_enabled: bool,
+    field_switch_blocked: bool,
+    block_reason: Option<String>,
+}
+
+impl<D: DataProvider> ValidationFormEditor<D> {
+    fn new(data_provider: D) -> Self {
+        let mut editor = FormEditor::new(data_provider);
+        // Enable validation by default
+        editor.set_validation_enabled(true);
+        Self {
+            editor,
+            has_unsaved_changes: false,
+            debug_message: "🔍 Validation Demo - Try typing in different fields!".to_string(),
+            command_buffer: String::new(),
+            validation_enabled: true,
+            field_switch_blocked: false,
+            block_reason: None,
+        }
+    }
+
+    // === COMMAND BUFFER HANDLING ===
+    fn clear_command_buffer(&mut self) {
+        self.command_buffer.clear();
+    }
+
+    fn add_to_command_buffer(&mut self, ch: char) {
+        self.command_buffer.push(ch);
+    }
+
+    fn get_command_buffer(&self) -> &str {
+        &self.command_buffer
+    }
+
+    fn has_pending_command(&self) -> bool {
+        !self.command_buffer.is_empty()
+    }
+
+    // === VALIDATION CONTROL ===
+    fn toggle_validation(&mut self) {
+        self.validation_enabled = !self.validation_enabled;
+        self.editor.set_validation_enabled(self.validation_enabled);
+        if self.validation_enabled {
+            self.debug_message = "✅ Validation ENABLED - Try exceeding limits!".to_string();
+        } else {
+            self.debug_message = "❌ Validation DISABLED - No limits enforced".to_string();
+        }
+    }
+
+    fn check_field_switch_allowed(&self) -> (bool, Option<String>) {
+        if !self.validation_enabled {
+            return (true, None);
+        }
+        let can_switch = self.editor.can_switch_fields();
+        let reason = if !can_switch {
+            self.editor.field_switch_block_reason()
+        } else {
+            None
+        };
+        (can_switch, reason)
+    }
+
+    fn get_validation_status(&self) -> String {
+        if !self.validation_enabled {
+            return "❌ DISABLED".to_string();
+        }
+        if self.field_switch_blocked {
+            return "🚫 SWITCH BLOCKED".to_string();
+        }
+        let summary = self.editor.validation_summary();
+        if summary.has_errors() {
+            format!("❌ {} ERRORS", summary.error_fields)
+        } else if summary.has_warnings() {
+            format!("⚠️  {} WARNINGS", summary.warning_fields)
+        } else if summary.validated_fields > 0 {
+            format!("✅ {} VALID", summary.valid_fields)
+        } else {
+            "🔍 READY".to_string()
+        }
+    }
+
+    fn validate_current_field(&mut self) {
+        let result = self.editor.validate_current_field();
+        match result {
+            ValidationResult::Valid => {
+                self.debug_message = "✅ Current field is valid!".to_string();
+            }
+            ValidationResult::Warning { message } => {
+                self.debug_message = format!("⚠️  Warning: {}", message);
+            }
+            ValidationResult::Error { message } => {
+                self.debug_message = format!("❌ Error: {}", message);
+            }
+        }
+    }
+
+    fn validate_all_fields(&mut self) {
+        let field_count = self.editor.data_provider().field_count();
+        for i in 0..field_count {
+            self.editor.validate_field(i);
+        }
+        let summary = self.editor.validation_summary();
+        self.debug_message = format!(
+            "🔍 Validated all fields: {} valid, {} warnings, {} errors",
+            summary.valid_fields, summary.warning_fields, summary.error_fields
+        );
+    }
+
+    fn clear_validation_results(&mut self) {
+        self.editor.clear_validation_results();
+        self.debug_message = "🧹 Cleared all validation results".to_string();
+    }
+
+    // === ENHANCED MOVEMENT WITH VALIDATION ===
+    fn move_left(&mut self) {
+        self.editor.move_left();
+        self.field_switch_blocked = false;
+        self.block_reason = None;
+    }
+
+    fn move_right(&mut self) {
+        self.editor.move_right();
+        self.field_switch_blocked = false;
+        self.block_reason = None;
+    }
+
+    fn move_up(&mut self) {
+        match self.editor.move_up() {
+            Ok(()) => {
+                self.update_field_validation_status();
+                self.field_switch_blocked = false;
+                self.block_reason = None;
+            }
+            Err(e) => {
+                self.field_switch_blocked = true;
+                self.block_reason = Some(e.to_string());
+                self.debug_message = format!("🚫 Field switch blocked: {}", e);
+            }
+        }
+    }
+
+    fn move_down(&mut self) {
+        match self.editor.move_down() {
+            Ok(()) => {
+                self.update_field_validation_status();
+                self.field_switch_blocked = false;
+                self.block_reason = None;
+            }
+            Err(e) => {
+                self.field_switch_blocked = true;
+                self.block_reason = Some(e.to_string());
+                self.debug_message = format!("🚫 Field switch blocked: {}", e);
+            }
+        }
+    }
+
+    fn move_line_start(&mut self) {
+        self.editor.move_line_start();
+    }
+
+    fn move_line_end(&mut self) {
+        self.editor.move_line_end();
+    }
+
+    fn move_word_next(&mut self) {
+        self.editor.move_word_next();
+    }
+
+    fn move_word_prev(&mut self) {
+        self.editor.move_word_prev();
+    }
+
+    fn move_word_end(&mut self) {
+        self.editor.move_word_end();
+    }
+
+    fn move_first_line(&mut self) {
+        self.editor.move_first_line();
+    }
+
+    fn move_last_line(&mut self) {
+        self.editor.move_last_line();
+    }
+
+    fn update_field_validation_status(&mut self) {
+        if !self.validation_enabled {
+            return;
+        }
+        let result = self.editor.validate_current_field();
+        match result {
+            ValidationResult::Valid => {
+                self.debug_message = format!("Field {}: ✅ Valid", self.editor.current_field() + 1);
+            }
+            ValidationResult::Warning { message } => {
+                self.debug_message = format!("Field {}: ⚠️  {}", self.editor.current_field() + 1, message);
+            }
+            ValidationResult::Error { message } => {
+                self.debug_message = format!("Field {}: ❌ {}", self.editor.current_field() + 1, message);
+            }
+        }
+    }
+
+    // === MODE TRANSITIONS ===
+    fn enter_edit_mode(&mut self) {
+        // Library will automatically update cursor to bar | in insert mode
+        self.editor.enter_edit_mode();
+        self.debug_message = "✏️  INSERT MODE - Cursor: Steady Bar | - Type to test validation".to_string();
+    }
+
+    fn enter_append_mode(&mut self) {
+        // Library will automatically update cursor to bar | in insert mode
+        self.editor.enter_append_mode();
+        self.debug_message = "✏️  INSERT (append) - Cursor: Steady Bar | - Validation active".to_string();
+    }
+
+    fn exit_edit_mode(&mut self) {
+        // Library will automatically update cursor to block █ in normal mode
+        self.editor.exit_edit_mode();
+        self.debug_message = "🔒 NORMAL MODE - Cursor: Steady Block █ - Press 'v' to validate current field".to_string();
+        self.update_field_validation_status();
+    }
+
+    fn insert_char(&mut self, ch: char) -> anyhow::Result<()> {
+        let result = self.editor.insert_char(ch);
+        if result.is_ok() {
+            self.has_unsaved_changes = true;
+            // Show real-time validation feedback
+            let validation_result = self.editor.validate_current_field();
+            match validation_result {
+                ValidationResult::Valid => {
+                    // Don't spam with valid messages, just show character count if applicable
+                    if let Some(limits) = self.get_current_field_limits() {
+                        let field_index = self.editor.current_field();
+                        if let Some(status) = limits.status_text(
+                            self.editor.data_provider().field_value(field_index)
+                        ) {
+                            self.debug_message = format!("✏️  {}", status);
+                        }
+                    }
+                }
+                ValidationResult::Warning { message } => {
+                    self.debug_message = format!("⚠️  {}", message);
+                }
+                ValidationResult::Error { message } => {
+                    self.debug_message = format!("❌ {}", message);
+                }
+            }
+        }
+        Ok(result?)
+    }
+
+    fn get_current_field_limits(&self) -> Option<&CharacterLimits> {
+        let validation_state = self.editor.validation_state();
+        let config = validation_state.get_field_config(self.editor.current_field())?;
+        config.character_limits.as_ref()
+    }
+
+    // === DELETE OPERATIONS ===
+    fn delete_backward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_backward();
+        if result.is_ok() {
+            self.has_unsaved_changes = true;
+            self.debug_message = "⌫ Deleted character".to_string();
+        }
+        Ok(result?)
+    }
+
+    fn delete_forward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_forward();
+        if result.is_ok() {
+            self.has_unsaved_changes = true;
+            self.debug_message = "⌦ Deleted character".to_string();
+        }
+        Ok(result?)
+    }
+
+    // === DELEGATE TO ORIGINAL EDITOR ===
+    fn current_field(&self) -> usize {
+        self.editor.current_field()
+    }
+
+    fn cursor_position(&self) -> usize {
+        self.editor.cursor_position()
+    }
+
+    fn mode(&self) -> AppMode {
+        self.editor.mode()
+    }
+
+    fn current_text(&self) -> &str {
+        let field_index = self.editor.current_field();
+        self.editor.data_provider().field_value(field_index)
+    }
+
+    fn data_provider(&self) -> &D {
+        self.editor.data_provider()
+    }
+
+    fn ui_state(&self) -> &canvas::EditorState {
+        self.editor.ui_state()
+    }
+
+    fn set_mode(&mut self, mode: AppMode) {
+        // Library automatically updates cursor for the mode
+        self.editor.set_mode(mode);
+    }
+
+    fn next_field(&mut self) {
+        match self.editor.next_field() {
+            Ok(()) => {
+                self.update_field_validation_status();
+                self.field_switch_blocked = false;
+                self.block_reason = None;
+            }
+            Err(e) => {
+                self.field_switch_blocked = true;
+                self.block_reason = Some(e.to_string());
+                self.debug_message = format!("🚫 Cannot move to next field: {}", e);
+            }
+        }
+    }
+
+    fn prev_field(&mut self) {
+        match self.editor.prev_field() {
+            Ok(()) => {
+                self.update_field_validation_status();
+                self.field_switch_blocked = false;
+                self.block_reason = None;
+            }
+            Err(e) => {
+                self.field_switch_blocked = true;
+                self.block_reason = Some(e.to_string());
+                self.debug_message = format!("🚫 Cannot move to previous field: {}", e);
+            }
+        }
+    }
+
+    // === STATUS AND DEBUG ===
+    fn set_debug_message(&mut self, msg: String) {
+        self.debug_message = msg;
+    }
+
+    fn debug_message(&self) -> &str {
+        &self.debug_message
+    }
+
+    fn has_unsaved_changes(&self) -> bool {
+        self.has_unsaved_changes
+    }
+}
+
+// Demo form data with different validation rules
+struct ValidationDemoData {
+    fields: Vec<(String, String)>,
+}
+
+impl ValidationDemoData {
+    fn new() -> Self {
+        Self {
+            fields: vec![
+                ("👤 Name (max 20)".to_string(), "".to_string()),
+                ("📧 Email (max 50, warn@40)".to_string(), "".to_string()),
+                ("🔑 Password (5-20 chars)".to_string(), "".to_string()),
+                ("🔢 ID (min 3, max 10)".to_string(), "".to_string()),
+                ("📝 Comment (min 10, max 100)".to_string(), "".to_string()),
+                ("🏷️  Tag (max 30, bytes)".to_string(), "".to_string()),
+                ("🌍 Unicode (width, min 2)".to_string(), "".to_string()),
+            ],
+        }
+    }
+}
+
+impl DataProvider for ValidationDemoData {
+    fn field_count(&self) -> usize {
+        self.fields.len()
+    }
+
+    fn field_name(&self, index: usize) -> &str {
+        &self.fields[index].0
+    }
+
+    fn field_value(&self, index: usize) -> &str {
+        &self.fields[index].1
+    }
+
+    fn set_field_value(&mut self, index: usize, value: String) {
+        self.fields[index].1 = value;
+    }
+
+    fn supports_suggestions(&self, _field_index: usize) -> bool {
+        false
+    }
+
+    fn display_value(&self, _index: usize) -> Option<&str> {
+        None
+    }
+
+    // 🎯 NEW: Validation configuration per field
+    fn validation_config(&self, field_index: usize) -> Option<ValidationConfig> {
+        match field_index {
+            0 => Some(ValidationConfig::with_max_length(20)), // Name: simple 20 char limit
+            1 => Some(
+                ValidationConfigBuilder::new()
+                    .with_character_limits(
+                        CharacterLimits::new(50).with_warning_threshold(40)
+                    )
+                    .build()
+            ), // Email: 50 chars with warning at 40
+            2 => Some(
+                ValidationConfigBuilder::new()
+                    .with_character_limits(CharacterLimits::new_range(5, 20))
+                    .build()
+            ), // Password: must be 5-20 characters (blocks field switching if 1-4 chars)
+            3 => Some(
+                ValidationConfigBuilder::new()
+                    .with_character_limits(CharacterLimits::new_range(3, 10))
+                    .build()
+            ), // ID: must be 3-10 characters (blocks field switching if 1-2 chars)
+            4 => Some(
+                ValidationConfigBuilder::new()
+                    .with_character_limits(CharacterLimits::new_range(10, 100))
+                    .build()
+            ), // Comment: must be 10-100 characters (blocks field switching if 1-9 chars)
+            5 => Some(
+                ValidationConfigBuilder::new()
+                    .with_character_limits(
+                        CharacterLimits::new(30).with_count_mode(CountMode::Bytes)
+                    )
+                    .build()
+            ), // Tag: 30 bytes (useful for UTF-8)
+            6 => Some(
+                ValidationConfigBuilder::new()
+                    .with_character_limits(
+                        CharacterLimits::new_range(2, 20).with_count_mode(CountMode::DisplayWidth)
+                    )
+                    .build()
+            ), // Unicode: 2-20 display width (useful for CJK characters, blocks if 1 char)
+            _ => None,
+        }
+    }
+}
+
+/// Handle key presses with validation-focused commands
+fn handle_key_press(
+    key: KeyCode,
+    modifiers: KeyModifiers,
+    editor: &mut ValidationFormEditor<ValidationDemoData>,
+) -> anyhow::Result<bool> {
+    let mode = editor.mode();
+
+    // Quit handling
+    if (key == KeyCode::Char('q') && modifiers.contains(KeyModifiers::CONTROL))
+        || (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL))
+        || key == KeyCode::F(10)
+    {
+        return Ok(false);
+    }
+
+    match (mode, key, modifiers) {
+        // === MODE TRANSITIONS ===
+        (AppMode::ReadOnly, KeyCode::Char('i'), _) => {
+            editor.enter_edit_mode();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('a'), _) => {
+            editor.enter_append_mode();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('A'), _) => {
+            editor.move_line_end();
+            editor.enter_edit_mode();
+            editor.clear_command_buffer();
+        }
+        // Escape: Exit edit mode
+        (_, KeyCode::Esc, _) => {
+            if mode == AppMode::Edit {
+                editor.exit_edit_mode();
+            } else {
+                editor.clear_command_buffer();
+            }
+        }
+
+        // === VALIDATION COMMANDS ===
+        (AppMode::ReadOnly, KeyCode::Char('v'), _) => {
+            editor.validate_current_field();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('V'), _) => {
+            editor.validate_all_fields();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('c'), _) => {
+            editor.clear_validation_results();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::F(1), _) => {
+            editor.toggle_validation();
+        }
+
+        // === MOVEMENT ===
+        (AppMode::ReadOnly, KeyCode::Char('h'), _) | (AppMode::ReadOnly, KeyCode::Left, _) => {
+            editor.move_left();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('l'), _) | (AppMode::ReadOnly, KeyCode::Right, _) => {
+            editor.move_right();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('j'), _) | (AppMode::ReadOnly, KeyCode::Down, _) => {
+            editor.move_down();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('k'), _) | (AppMode::ReadOnly, KeyCode::Up, _) => {
+            editor.move_up();
+            editor.clear_command_buffer();
+        }
+
+        // === EDIT MODE MOVEMENT ===
+        (AppMode::Edit, KeyCode::Left, _) => {
+            editor.move_left();
+        }
+        (AppMode::Edit, KeyCode::Right, _) => {
+            editor.move_right();
+        }
+        (AppMode::Edit, KeyCode::Up, _) => {
+            editor.move_up();
+        }
+        (AppMode::Edit, KeyCode::Down, _) => {
+            editor.move_down();
+        }
+
+        // === DELETE OPERATIONS ===
+        (AppMode::Edit, KeyCode::Backspace, _) => {
+            editor.delete_backward()?;
+        }
+        (AppMode::Edit, KeyCode::Delete, _) => {
+            editor.delete_forward()?;
+        }
+
+        // === TAB NAVIGATION ===
+        (_, KeyCode::Tab, _) => {
+            editor.next_field();
+        }
+        (_, KeyCode::BackTab, _) => {
+            editor.prev_field();
+        }
+
+        // === CHARACTER INPUT ===
+        (AppMode::Edit, KeyCode::Char(c), m) if !m.contains(KeyModifiers::CONTROL) => {
+            editor.insert_char(c)?;
+        }
+
+        // === DEBUG/INFO COMMANDS ===
+        (AppMode::ReadOnly, KeyCode::Char('?'), _) => {
+            let summary = editor.editor.validation_summary();
+            editor.set_debug_message(format!(
+                "Field {}/{}, Pos {}, Mode: {:?}, Validation: {} fields configured, {} validated",
+                editor.current_field() + 1,
+                editor.data_provider().field_count(),
+                editor.cursor_position(),
+                editor.mode(),
+                summary.total_fields,
+                summary.validated_fields
+            ));
+        }
+        _ => {
+            if editor.has_pending_command() {
+                editor.clear_command_buffer();
+                editor.set_debug_message("Invalid command sequence".to_string());
+            }
+        }
+    }
+
+    Ok(true)
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut editor: ValidationFormEditor<ValidationDemoData>,
+) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f, &editor))?;
+
+        if let Event::Key(key) = event::read()? {
+            match handle_key_press(key.code, key.modifiers, &mut editor) {
+                Ok(should_continue) => {
+                    if !should_continue {
+                        break;
+                    }
+                }
+                Err(e) => {
+                    editor.set_debug_message(format!("Error: {}", e));
+                }
+            }
+        }
+    }
+    Ok(())
+}
+
+fn ui(f: &mut Frame, editor: &ValidationFormEditor<ValidationDemoData>) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Min(8), Constraint::Length(12)])
+        .split(f.area());
+
+    render_enhanced_canvas(f, chunks[0], editor);
+    render_validation_status(f, chunks[1], editor);
+}
+
+fn render_enhanced_canvas(
+    f: &mut Frame,
+    area: Rect,
+    editor: &ValidationFormEditor<ValidationDemoData>,
+) {
+    render_canvas_default(f, area, &editor.editor);
+}
+
+fn render_validation_status(
+    f: &mut Frame,
+    area: Rect,
+    editor: &ValidationFormEditor<ValidationDemoData>,
+) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([
+            Constraint::Length(3), // Status bar
+            Constraint::Length(4), // Validation summary
+            Constraint::Length(5), // Help
+        ])
+        .split(area);
+
+    // Status bar with validation information
+    let mode_text = match editor.mode() {
+        AppMode::Edit => "INSERT | (bar cursor)",
+        AppMode::ReadOnly => "NORMAL █ (block cursor)",
+        _ => "NORMAL █ (block cursor)",
+    };
+
+    let validation_status = editor.get_validation_status();
+
+    let status_text = if editor.has_pending_command() {
+        format!("-- {} -- {} [{}] | Validation: {}",
+                mode_text, editor.debug_message(), editor.get_command_buffer(), validation_status)
+    } else if editor.has_unsaved_changes() {
+        format!("-- {} -- [Modified] {} | Validation: {}",
+                mode_text, editor.debug_message(), validation_status)
+    } else {
+        format!("-- {} -- {} | Validation: {}",
+                mode_text, editor.debug_message(), validation_status)
+    };
+
+    let status = Paragraph::new(Line::from(Span::raw(status_text)))
+        .block(Block::default().borders(Borders::ALL).title("🔍 Validation Status"));
+    f.render_widget(status, chunks[0]);
+
+    // Validation summary with field switching info
+    let summary = editor.editor.validation_summary();
+    let summary_text = if editor.validation_enabled {
+        let switch_info = if editor.field_switch_blocked {
+            format!("\n🚫 Field switching blocked: {}",
+                   editor.block_reason.as_deref().unwrap_or("Unknown reason"))
+        } else {
+            let (can_switch, reason) = editor.check_field_switch_allowed();
+            if !can_switch {
+                format!("\n⚠️  Field switching will be blocked: {}",
+                       reason.as_deref().unwrap_or("Unknown reason"))
+            } else {
+                "\n✅ Field switching allowed".to_string()
+            }
+        };
+        
+        format!(
+            "📊 Validation Summary: {} fields configured, {} validated{}\n\
+             ✅ Valid: {}  ⚠️  Warnings: {}  ❌ Errors: {}  📈 Progress: {:.0}%",
+            summary.total_fields,
+            summary.validated_fields,
+            switch_info,
+            summary.valid_fields,
+            summary.warning_fields,
+            summary.error_fields,
+            summary.completion_percentage() * 100.0
+        )
+    } else {
+        "❌ Validation is currently DISABLED\nPress F1 to enable validation".to_string()
+    };
+
+    let summary_style = if summary.has_errors() {
+        Style::default().fg(Color::Red)
+    } else if summary.has_warnings() {
+        Style::default().fg(Color::Yellow)
+    } else {
+        Style::default().fg(Color::Green)
+    };
+
+    let validation_summary = Paragraph::new(summary_text)
+        .block(Block::default().borders(Borders::ALL).title("📈 Validation Overview"))
+        .style(summary_style)
+        .wrap(Wrap { trim: true });
+    f.render_widget(validation_summary, chunks[1]);
+
+    // Enhanced help text
+    let help_text = match editor.mode() {
+        AppMode::ReadOnly => {
+            "🎯 CURSOR-STYLE: Normal █ | Insert |\n\
+             🔍 VALIDATION: Different fields have different limits (some block field switching)!\n\
+             Movement: hjkl/arrows=move, Tab/Shift+Tab=fields\n\
+             Edit: i/a/A=insert modes, Esc=normal\n\
+             Validation: v=validate current, V=validate all, c=clear results, F1=toggle\n\
+             ?=info, Ctrl+C/Ctrl+Q=quit"
+        }
+        AppMode::Edit => {
+            "🎯 INSERT MODE - Cursor: | (bar)\n\
+             🔍 Type to test validation limits (some fields have MIN requirements)!\n\
+             Try typing 1-2 chars in Password/ID/Comment fields, then try to switch!\n\
+             arrows=move, Backspace/Del=delete, Esc=normal, Tab=next field\n\
+             Field switching may be BLOCKED if minimum requirements not met!"
+        }
+        _ => "🎯 Watch the cursor change automatically while validating!"
+    };
+
+    let help = Paragraph::new(help_text)
+        .block(Block::default().borders(Borders::ALL).title("🚀 Validation Commands"))
+        .style(Style::default().fg(Color::Gray))
+        .wrap(Wrap { trim: true });
+    f.render_widget(help, chunks[2]);
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Print feature status
+    println!("🔍 Canvas Validation Demo");
+    println!("✅ validation feature: ENABLED");
+    println!("🚀 Field validation: ACTIVE");
+    println!("🚫 Field switching validation: ACTIVE");
+    println!("📊 Try typing in fields with minimum requirements!");
+    println!("   - Password (min 5): Type 1-4 chars, then try to switch fields");
+    println!("   - ID (min 3): Type 1-2 chars, then try to switch fields");
+    println!("   - Comment (min 10): Type 1-9 chars, then try to switch fields");
+    println!("   - Unicode (min 2): Type 1 char, then try to switch fields");
+    println!();
+
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    let data = ValidationDemoData::new();
+    let mut editor = ValidationFormEditor::new(data);
+    
+    // Initialize with normal mode - library automatically sets block cursor
+    editor.set_mode(AppMode::ReadOnly);
+    
+    // Demonstrate that CursorManager is available and working
+    CursorManager::update_for_mode(AppMode::ReadOnly)?;
+
+    let res = run_app(&mut terminal, editor);
+
+    // Library automatically resets cursor on FormEditor::drop()
+    // But we can also manually reset if needed
+    CursorManager::reset()?;
+
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err);
+    }
+
+    println!("🔍 Validation demo completed!");
+    Ok(())
+}
--- a/canvas/examples/validation_2.rs
+++ b/canvas/examples/validation_2.rs
@@ -0,0 +1,663 @@
+// examples/validation_2.rs
+//! Advanced TUI Example demonstrating complex pattern filtering edge cases
+//!
+//! This example showcases the full potential of the pattern validation system
+//! with creative real-world scenarios and edge cases.
+//!
+//! Run with: cargo run --example validation_advanced_patterns --features "validation,gui,cursor-style"
+
+// REQUIRE validation, gui and cursor-style features
+#[cfg(not(all(feature = "validation", feature = "gui", feature = "cursor-style")))]
+compile_error!(
+    "This example requires the 'validation', 'gui' and 'cursor-style' features. \
+     Run with: cargo run --example validation_advanced_patterns --features \"validation,gui,cursor-style\""
+);
+
+use std::io;
+use std::sync::Arc;
+use canvas::ValidationResult;
+use crossterm::{
+    event::{
+        self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers,
+    },
+    execute,
+    terminal::{
+        disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen,
+    },
+};
+use ratatui::{
+    backend::{Backend, CrosstermBackend},
+    layout::{Constraint, Direction, Layout, Rect},
+    style::{Color, Style},
+    text::{Line, Span},
+    widgets::{Block, Borders, Paragraph, Wrap},
+    Frame, Terminal,
+};
+
+use canvas::{
+    canvas::{
+        gui::render_canvas_default,
+        modes::AppMode,
+        CursorManager,
+    },
+    DataProvider, FormEditor,
+    ValidationConfig, ValidationConfigBuilder, PatternFilters, PositionFilter, PositionRange, CharacterFilter,
+};
+
+// Enhanced FormEditor wrapper (keeping the same structure as before)
+struct AdvancedPatternFormEditor<D: DataProvider> {
+    editor: FormEditor<D>,
+    debug_message: String,
+    command_buffer: String,
+    validation_enabled: bool,
+    field_switch_blocked: bool,
+    block_reason: Option<String>,
+}
+
+impl<D: DataProvider> AdvancedPatternFormEditor<D> {
+    fn new(data_provider: D) -> Self {
+        let mut editor = FormEditor::new(data_provider);
+        editor.set_validation_enabled(true);
+
+        Self {
+            editor,
+            debug_message: "🚀 Advanced Pattern Validation - Showcasing edge cases and complex patterns!".to_string(),
+            command_buffer: String::new(),
+            validation_enabled: true,
+            field_switch_blocked: false,
+            block_reason: None,
+        }
+    }
+
+    // ... (keeping all the same methods as before for brevity)
+    // [All the previous methods: clear_command_buffer, add_to_command_buffer, etc.]
+
+    fn clear_command_buffer(&mut self) { self.command_buffer.clear(); }
+    fn add_to_command_buffer(&mut self, ch: char) { self.command_buffer.push(ch); }
+    fn get_command_buffer(&self) -> &str { &self.command_buffer }
+    fn has_pending_command(&self) -> bool { !self.command_buffer.is_empty() }
+
+    fn toggle_validation(&mut self) {
+        self.validation_enabled = !self.validation_enabled;
+        self.editor.set_validation_enabled(self.validation_enabled);
+        if self.validation_enabled {
+            self.debug_message = "✅ Advanced Pattern Validation ENABLED".to_string();
+        } else {
+            self.debug_message = "❌ Advanced Pattern Validation DISABLED".to_string();
+        }
+    }
+
+    fn move_left(&mut self) { self.editor.move_left(); self.field_switch_blocked = false; self.block_reason = None; }
+    fn move_right(&mut self) { self.editor.move_right(); self.field_switch_blocked = false; self.block_reason = None; }
+
+    fn move_up(&mut self) {
+        match self.editor.move_up() {
+            Ok(()) => { self.update_field_validation_status(); self.field_switch_blocked = false; self.block_reason = None; }
+            Err(e) => { self.field_switch_blocked = true; self.block_reason = Some(e.to_string()); self.debug_message = format!("🚫 Field switch blocked: {}", e); }
+        }
+    }
+
+    fn move_down(&mut self) {
+        match self.editor.move_down() {
+            Ok(()) => { self.update_field_validation_status(); self.field_switch_blocked = false; self.block_reason = None; }
+            Err(e) => { self.field_switch_blocked = true; self.block_reason = Some(e.to_string()); self.debug_message = format!("🚫 Field switch blocked: {}", e); }
+        }
+    }
+
+    fn move_line_start(&mut self) { self.editor.move_line_start(); }
+    fn move_line_end(&mut self) { self.editor.move_line_end(); }
+
+    fn enter_edit_mode(&mut self) {
+        // Library will automatically update cursor to bar | in insert mode
+        self.editor.enter_edit_mode();
+        self.debug_message = "✏️  INSERT MODE - Cursor: Steady Bar | - Testing advanced pattern validation".to_string();
+    }
+
+    fn enter_append_mode(&mut self) {
+        // Library will automatically update cursor to bar | in insert mode
+        self.editor.enter_append_mode();
+        self.debug_message = "✏️  INSERT (append) - Cursor: Steady Bar | - Advanced patterns active".to_string();
+    }
+
+    fn exit_edit_mode(&mut self) {
+        // Library will automatically update cursor to block █ in normal mode
+        self.editor.exit_edit_mode();
+        self.debug_message = "🔒 NORMAL MODE - Cursor: Steady Block █".to_string();
+        self.update_field_validation_status();
+    }
+
+    fn insert_char(&mut self, ch: char) -> anyhow::Result<()> {
+        let result = self.editor.insert_char(ch);
+        if result.is_ok() {
+            let validation_result = self.editor.validate_current_field();
+            match validation_result {
+                ValidationResult::Valid => { self.debug_message = "✅ Character accepted".to_string(); }
+                ValidationResult::Warning { message } => { self.debug_message = format!("⚠️  Warning: {}", message); }
+                ValidationResult::Error { message } => { self.debug_message = format!("❌ Pattern violation: {}", message); }
+            }
+        }
+        Ok(result?)
+    }
+
+    fn delete_backward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_backward();
+        if result.is_ok() { self.debug_message = "⌫ Character deleted".to_string(); }
+        Ok(result?)
+    }
+
+    fn delete_forward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_forward();
+        if result.is_ok() { self.debug_message = "⌦ Character deleted".to_string(); }
+        Ok(result?)
+    }
+
+    // Delegate methods
+    fn current_field(&self) -> usize { self.editor.current_field() }
+    fn cursor_position(&self) -> usize { self.editor.cursor_position() }
+    fn mode(&self) -> AppMode { self.editor.mode() }
+    fn current_text(&self) -> &str {
+        let field_index = self.editor.current_field();
+        self.editor.data_provider().field_value(field_index)
+    }
+    fn data_provider(&self) -> &D { self.editor.data_provider() }
+    fn ui_state(&self) -> &canvas::EditorState { self.editor.ui_state() }
+    fn set_mode(&mut self, mode: AppMode) { self.editor.set_mode(mode); }
+
+    fn next_field(&mut self) {
+        match self.editor.next_field() {
+            Ok(()) => { self.update_field_validation_status(); self.field_switch_blocked = false; self.block_reason = None; }
+            Err(e) => { self.field_switch_blocked = true; self.block_reason = Some(e.to_string()); self.debug_message = format!("🚫 Cannot move to next field: {}", e); }
+        }
+    }
+
+    fn prev_field(&mut self) {
+        match self.editor.prev_field() {
+            Ok(()) => { self.update_field_validation_status(); self.field_switch_blocked = false; self.block_reason = None; }
+            Err(e) => { self.field_switch_blocked = true; self.block_reason = Some(e.to_string()); self.debug_message = format!("🚫 Cannot move to previous field: {}", e); }
+        }
+    }
+
+    fn set_debug_message(&mut self, msg: String) { self.debug_message = msg; }
+    fn debug_message(&self) -> &str { &self.debug_message }
+
+    fn update_field_validation_status(&mut self) {
+        if !self.validation_enabled { return; }
+        let result = self.editor.validate_current_field();
+        match result {
+            ValidationResult::Valid => { self.debug_message = format!("Field {}: ✅ Pattern valid", self.editor.current_field() + 1); }
+            ValidationResult::Warning { message } => { self.debug_message = format!("Field {}: ⚠️  {}", self.editor.current_field() + 1, message); }
+            ValidationResult::Error { message } => { self.debug_message = format!("Field {}: ❌ {}", self.editor.current_field() + 1, message); }
+        }
+    }
+
+    fn get_validation_status(&self) -> String {
+        if !self.validation_enabled { return "❌ DISABLED".to_string(); }
+        if self.field_switch_blocked { return "🚫 SWITCH BLOCKED".to_string(); }
+        let summary = self.editor.validation_summary();
+        if summary.has_errors() { format!("❌ {} ERRORS", summary.error_fields) }
+        else if summary.has_warnings() { format!("⚠️  {} WARNINGS", summary.warning_fields) }
+        else if summary.validated_fields > 0 { format!("✅ {} VALID", summary.valid_fields) }
+        else { "🔍 READY".to_string() }
+    }
+}
+
+// Advanced demo form with creative and edge-case-heavy validation patterns
+struct AdvancedPatternData {
+    fields: Vec<(String, String)>,
+}
+
+impl AdvancedPatternData {
+    fn new() -> Self {
+        Self {
+            fields: vec![
+                ("🕐 Time (HH:MM) - 24hr format".to_string(), "".to_string()),
+                ("🎨 Hex Color (#RRGGBB) - Web colors".to_string(), "".to_string()),
+                ("🌐 IPv4 (XXX.XXX.XXX.XXX) - Network address".to_string(), "".to_string()),
+                ("🏷️  Product Code (ABC-123-XYZ) - Mixed format".to_string(), "".to_string()),
+                ("📅 Date Code (2024W15) - Year + Week".to_string(), "".to_string()),
+                ("🔢 Binary (101010) - Only 0s and 1s".to_string(), "".to_string()),
+                ("🎯 Complex ID (A1-B2C-3D4E) - Multi-rule".to_string(), "".to_string()),
+                ("🚀 Custom Pattern - Advanced logic".to_string(), "".to_string()),
+            ],
+        }
+    }
+}
+
+impl DataProvider for AdvancedPatternData {
+    fn field_count(&self) -> usize { self.fields.len() }
+    fn field_name(&self, index: usize) -> &str { &self.fields[index].0 }
+    fn field_value(&self, index: usize) -> &str { &self.fields[index].1 }
+    fn set_field_value(&mut self, index: usize, value: String) { self.fields[index].1 = value; }
+
+    fn validation_config(&self, field_index: usize) -> Option<ValidationConfig> {
+        match field_index {
+            0 => {
+                // 🕐 Time (HH:MM) - Hours 00-23, Minutes 00-59
+                // This showcases: Multiple position ranges, exact character matching, custom validation
+                let time_pattern = PatternFilters::new()
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Multiple(vec![0, 1, 3, 4]), // Hours and minutes positions
+                        CharacterFilter::Numeric,
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Single(2), // Colon separator
+                        CharacterFilter::Exact(':'),
+                    ));
+
+                Some(ValidationConfigBuilder::new()
+                    .with_pattern_filters(time_pattern)
+                    .with_max_length(5) // HH:MM = 5 characters
+                    .build())
+            }
+            1 => {
+                // 🎨 Hex Color (#RRGGBB) - Web color format
+                // This showcases: OneOf filter with hex digits, exact character at start
+                let hex_digits = vec!['0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F','a','b','c','d','e','f'];
+                let hex_color_pattern = PatternFilters::new()
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Single(0), // Hash symbol
+                        CharacterFilter::Exact('#'),
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Range(1, 6), // 6 hex digits for RGB
+                        CharacterFilter::OneOf(hex_digits),
+                    ));
+
+                Some(ValidationConfigBuilder::new()
+                    .with_pattern_filters(hex_color_pattern)
+                    .with_max_length(7) // #RRGGBB = 7 characters
+                    .build())
+            }
+            2 => {
+                // 🌐 IPv4 Address (XXX.XXX.XXX.XXX) - Network address
+                // This showcases: Complex pattern with dots at specific positions
+                let ipv4_pattern = PatternFilters::new()
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Multiple(vec![3, 7, 11]), // Dots at specific positions
+                        CharacterFilter::Exact('.'),
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Multiple(vec![0,1,2,4,5,6,8,9,10,12,13,14]), // Number positions
+                        CharacterFilter::Numeric,
+                    ));
+
+                Some(ValidationConfigBuilder::new()
+                    .with_pattern_filters(ipv4_pattern)
+                    .with_max_length(15) // XXX.XXX.XXX.XXX = up to 15 chars
+                    .build())
+            }
+            3 => {
+                // 🏷️ Product Code (ABC-123-XYZ) - Mixed format sections
+                // This showcases: Different rules for different sections
+                let product_code_pattern = PatternFilters::new()
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Range(0, 2), // First 3 positions: letters
+                        CharacterFilter::Alphabetic,
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Multiple(vec![3, 7]), // Dashes
+                        CharacterFilter::Exact('-'),
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Range(4, 6), // Middle 3 positions: numbers
+                        CharacterFilter::Numeric,
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Range(8, 10), // Last 3 positions: letters
+                        CharacterFilter::Alphabetic,
+                    ));
+
+                Some(ValidationConfigBuilder::new()
+                    .with_pattern_filters(product_code_pattern)
+                    .with_max_length(11) // ABC-123-XYZ = 11 characters
+                    .build())
+            }
+            4 => {
+                // 📅 Date Code (2024W15) - Year + Week format
+                // This showcases: From position filtering and mixed patterns
+                let date_code_pattern = PatternFilters::new()
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Range(0, 3), // Year: 4 digits
+                        CharacterFilter::Numeric,
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Single(4), // Week indicator
+                        CharacterFilter::Exact('W'),
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::From(5), // Week number: rest are digits
+                        CharacterFilter::Numeric,
+                    ));
+
+                Some(ValidationConfigBuilder::new()
+                    .with_pattern_filters(date_code_pattern)
+                    .with_max_length(7) // 2024W15 = 7 characters
+                    .build())
+            }
+            5 => {
+                // 🔢 Binary (101010) - Only 0s and 1s
+                // This showcases: OneOf filter with limited character set
+                let binary_pattern = PatternFilters::new()
+                    .add_filter(PositionFilter::new(
+                        PositionRange::From(0), // All positions
+                        CharacterFilter::OneOf(vec!['0', '1']),
+                    ));
+
+                Some(ValidationConfigBuilder::new()
+                    .with_pattern_filters(binary_pattern)
+                    .with_max_length(16) // Allow up to 16 binary digits
+                    .build())
+            }
+            6 => {
+                // 🎯 Complex ID (A1-B2C-3D4E) - Multiple overlapping rules
+                // This showcases: Complex overlapping patterns and edge cases
+                let complex_id_pattern = PatternFilters::new()
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Multiple(vec![0, 3, 6, 8]), // Letter positions
+                        CharacterFilter::Alphabetic,
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Multiple(vec![1, 4, 7, 9]), // Number positions
+                        CharacterFilter::Numeric,
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Multiple(vec![2, 5]), // Dashes
+                        CharacterFilter::Exact('-'),
+                    ))
+                    .add_filter(PositionFilter::new(
+                        PositionRange::Single(5), // Special case: override dash with letter C
+                        CharacterFilter::Alphabetic, // This creates an interesting edge case
+                    ));
+
+                Some(ValidationConfigBuilder::new()
+                    .with_pattern_filters(complex_id_pattern)
+                    .with_max_length(10) // A1-B2C-3D4E = 10 characters
+                    .build())
+            }
+            7 => {
+                // 🚀 Custom Pattern - Advanced logic with custom function
+                // This showcases: Custom validation function for complex rules
+                let custom_pattern = PatternFilters::new()
+                    .add_filter(PositionFilter::new(
+                        PositionRange::From(0),
+                        CharacterFilter::Custom(Arc::new(|c| {
+                            // Advanced rule: Alternating vowels and consonants!
+                            // Even positions (0,2,4...): vowels (a,e,i,o,u)
+                            // Odd positions (1,3,5...): consonants
+                            let vowels = ['a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U'];
+
+                            // For demo purposes, we'll just accept alphabetic characters
+                            // In real usage, you'd implement the alternating logic based on position
+                            c.is_alphabetic()
+                        })),
+                    ));
+
+                Some(ValidationConfigBuilder::new()
+                    .with_pattern_filters(custom_pattern)
+                    .with_max_length(12) // Allow up to 12 characters
+                    .build())
+            }
+            _ => None,
+        }
+    }
+}
+
+// Key handling (same structure as before)
+fn handle_key_press(
+    key: KeyCode,
+    modifiers: KeyModifiers,
+    editor: &mut AdvancedPatternFormEditor<AdvancedPatternData>,
+) -> anyhow::Result<bool> {
+    let mode = editor.mode();
+
+    // Quit handling
+    if (key == KeyCode::Char('q') && modifiers.contains(KeyModifiers::CONTROL))
+        || (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL))
+        || key == KeyCode::F(10)
+    {
+        return Ok(false);
+    }
+
+    match (mode, key, modifiers) {
+        // Mode transitions
+        (AppMode::ReadOnly, KeyCode::Char('i'), _) => { editor.enter_edit_mode(); editor.clear_command_buffer(); }
+        (AppMode::ReadOnly, KeyCode::Char('a'), _) => { editor.enter_append_mode(); editor.clear_command_buffer(); }
+        (AppMode::ReadOnly, KeyCode::Char('A'), _) => { editor.move_line_end(); editor.enter_edit_mode(); editor.clear_command_buffer(); }
+        (_, KeyCode::Esc, _) => { if mode == AppMode::Edit { editor.exit_edit_mode(); } else { editor.clear_command_buffer(); } }
+
+        // Validation commands
+        (AppMode::ReadOnly, KeyCode::F(1), _) => { editor.toggle_validation(); }
+
+        // Movement in ReadOnly mode
+        (AppMode::ReadOnly, KeyCode::Char('h'), _) | (AppMode::ReadOnly, KeyCode::Left, _) => { editor.move_left(); editor.clear_command_buffer(); }
+        (AppMode::ReadOnly, KeyCode::Char('l'), _) | (AppMode::ReadOnly, KeyCode::Right, _) => { editor.move_right(); editor.clear_command_buffer(); }
+        (AppMode::ReadOnly, KeyCode::Char('j'), _) | (AppMode::ReadOnly, KeyCode::Down, _) => { editor.move_down(); editor.clear_command_buffer(); }
+        (AppMode::ReadOnly, KeyCode::Char('k'), _) | (AppMode::ReadOnly, KeyCode::Up, _) => { editor.move_up(); editor.clear_command_buffer(); }
+
+        // Movement in Edit mode
+        (AppMode::Edit, KeyCode::Left, _) => { editor.move_left(); }
+        (AppMode::Edit, KeyCode::Right, _) => { editor.move_right(); }
+        (AppMode::Edit, KeyCode::Up, _) => { editor.move_up(); }
+        (AppMode::Edit, KeyCode::Down, _) => { editor.move_down(); }
+
+        // Delete operations
+        (AppMode::Edit, KeyCode::Backspace, _) => { editor.delete_backward()?; }
+        (AppMode::Edit, KeyCode::Delete, _) => { editor.delete_forward()?; }
+
+        // Tab navigation
+        (_, KeyCode::Tab, _) => { editor.next_field(); }
+        (_, KeyCode::BackTab, _) => { editor.prev_field(); }
+
+        // Character input
+        (AppMode::Edit, KeyCode::Char(c), m) if !m.contains(KeyModifiers::CONTROL) => {
+            editor.insert_char(c)?;
+        }
+
+        // Debug info
+        (AppMode::ReadOnly, KeyCode::Char('?'), _) => {
+            let summary = editor.editor.validation_summary();
+            editor.set_debug_message(format!(
+                "Field {}/{}, Pos {}, Mode: {:?}, Advanced patterns: {} configured",
+                editor.current_field() + 1,
+                editor.data_provider().field_count(),
+                editor.cursor_position(),
+                editor.mode(),
+                summary.total_fields
+            ));
+        }
+
+        _ => {
+            if editor.has_pending_command() {
+                editor.clear_command_buffer();
+                editor.set_debug_message("Invalid command sequence".to_string());
+            }
+        }
+    }
+
+    Ok(true)
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut editor: AdvancedPatternFormEditor<AdvancedPatternData>,
+) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f, &editor))?;
+
+        if let Event::Key(key) = event::read()? {
+            match handle_key_press(key.code, key.modifiers, &mut editor) {
+                Ok(should_continue) => {
+                    if !should_continue {
+                        break;
+                    }
+                }
+                Err(e) => {
+                    editor.set_debug_message(format!("Error: {}", e));
+                }
+            }
+        }
+    }
+
+    Ok(())
+}
+
+fn ui(f: &mut Frame, editor: &AdvancedPatternFormEditor<AdvancedPatternData>) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Min(8), Constraint::Length(15)])
+        .split(f.area());
+
+    render_canvas_default(f, chunks[0], &editor.editor);
+    render_advanced_validation_status(f, chunks[1], editor);
+}
+
+fn render_advanced_validation_status(
+    f: &mut Frame,
+    area: Rect,
+    editor: &AdvancedPatternFormEditor<AdvancedPatternData>,
+) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([
+            Constraint::Length(3), // Status bar
+            Constraint::Length(5), // Validation summary
+            Constraint::Length(7), // Help
+        ])
+        .split(area);
+
+    // Status bar
+    let mode_text = match editor.mode() {
+        AppMode::Edit => "INSERT | (bar cursor)",
+        AppMode::ReadOnly => "NORMAL █ (block cursor)",
+        _ => "NORMAL █ (block cursor)",
+    };
+
+    let validation_status = editor.get_validation_status();
+    let status_text = format!("-- {} -- {} | Advanced Patterns: {}", mode_text, editor.debug_message(), validation_status);
+
+    let status = Paragraph::new(Line::from(Span::raw(status_text)))
+        .block(Block::default().borders(Borders::ALL).title("🚀 Advanced Pattern Validation"));
+
+    f.render_widget(status, chunks[0]);
+
+    // Enhanced validation summary
+    let summary = editor.editor.validation_summary();
+    let field_info = match editor.current_field() {
+        0 => "Time format (HH:MM) - Tests exact chars + numeric ranges",
+        1 => "Hex color (#RRGGBB) - Tests OneOf filter with case insensitive",
+        2 => "IPv4 address - Tests complex dot positioning",
+        3 => "Product code (ABC-123-XYZ) - Tests section-based patterns",
+        4 => "Date code (2024W15) - Tests From position filtering",
+        5 => "Binary input - Tests limited character set (0,1 only)",
+        6 => "Complex ID - Tests overlapping/conflicting rules",
+        7 => "Custom pattern - Tests advanced custom validation logic",
+        _ => "Unknown field",
+    };
+
+    let summary_text = if editor.validation_enabled {
+        format!(
+            "📊 Advanced Pattern Summary: {} fields with complex rules\n\
+             Current Field: {}\n\
+             ✅ Valid: {}  ⚠️  Warnings: {}  ❌ Errors: {}  📈 Progress: {:.0}%\n\
+             🎯 Pattern Focus: {}",
+            summary.total_fields,
+            editor.current_field() + 1,
+            summary.valid_fields,
+            summary.warning_fields,
+            summary.error_fields,
+            summary.completion_percentage() * 100.0,
+            field_info
+        )
+    } else {
+        "❌ Advanced pattern validation is DISABLED\nPress F1 to enable and see the magic!".to_string()
+    };
+
+    let summary_style = if summary.has_errors() {
+        Style::default().fg(Color::Red)
+    } else if summary.has_warnings() {
+        Style::default().fg(Color::Yellow)
+    } else {
+        Style::default().fg(Color::Green)
+    };
+
+    let validation_summary = Paragraph::new(summary_text)
+        .block(Block::default().borders(Borders::ALL).title("🎯 Advanced Pattern Analysis"))
+        .style(summary_style)
+        .wrap(Wrap { trim: true });
+
+    f.render_widget(validation_summary, chunks[1]);
+
+    // Enhanced help text
+    let help_text = match editor.mode() {
+        AppMode::ReadOnly => {
+            "🚀 ADVANCED PATTERN SHOWCASE - Each field demonstrates different edge cases!\n\
+             🕐 Time: Numeric+exact chars  🎨 Hex: OneOf with case-insensitive  🌐 IPv4: Complex positioning\n\
+             🏷️  Product: Multi-section rules  📅 Date: From-position filtering  🔢 Binary: Limited charset\n\
+             🎯 Complex: Overlapping rules  🚀 Custom: Advanced logic functions\n\
+             \n\
+             Movement: hjkl/arrows=move, Tab/Shift+Tab=fields, i/a=insert, F1=toggle, ?=info"
+        }
+        AppMode::Edit => {
+            "✏️  INSERT MODE - Testing advanced pattern validation!\n\
+             Each character is validated against complex rules in real-time\n\
+             Try entering invalid characters to see detailed error messages\n\
+             arrows=move, Backspace/Del=delete, Esc=normal, Tab=next field"
+        }
+        _ => "🚀 Advanced Pattern Validation Active!"
+    };
+
+    let help = Paragraph::new(help_text)
+        .block(Block::default().borders(Borders::ALL).title("🎯 Advanced Pattern Commands & Info"))
+        .style(Style::default().fg(Color::Gray))
+        .wrap(Wrap { trim: true });
+
+    f.render_widget(help, chunks[2]);
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    println!("🚀 Canvas Advanced Pattern Validation Demo");
+    println!("✅ validation feature: ENABLED");
+    println!("✅ gui feature: ENABLED");
+    println!("✅ cursor-style feature: ENABLED");
+    println!("🎯 Advanced pattern filtering: ACTIVE");
+    println!("🧪 Edge cases and complex patterns: READY");
+    println!("💡 Each field showcases different validation capabilities!");
+    println!();
+
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    let data = AdvancedPatternData::new();
+    let mut editor = AdvancedPatternFormEditor::new(data);
+
+    // Initialize with normal mode - library automatically sets block cursor
+    editor.set_mode(AppMode::ReadOnly);
+
+    // Demonstrate that CursorManager is available and working
+    CursorManager::update_for_mode(AppMode::ReadOnly)?;
+
+    let res = run_app(&mut terminal, editor);
+
+    // Library automatically resets cursor on FormEditor::drop()
+    // But we can also manually reset if needed
+    CursorManager::reset()?;
+
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err);
+    }
+
+    println!("🚀 Advanced pattern validation demo completed!");
+    println!("🎯 Hope you enjoyed seeing all the edge cases in action!");
+    Ok(())
+}
--- a/canvas/examples/validation_3.rs
+++ b/canvas/examples/validation_3.rs
@@ -0,0 +1,735 @@
+// examples/validation_3.rs
+//! Comprehensive Display Mask Features Demo
+//!
+//! This example showcases the full power of the display mask system (Feature 3)
+//! demonstrating visual formatting that keeps business logic clean.
+//!
+//! Key Features Demonstrated:
+//! - Dynamic vs Template display modes
+//! - Custom patterns for different data types
+//! - Custom input characters and separators
+//! - Custom placeholder characters
+//! - Real-time visual formatting with clean raw data
+//! - Cursor movement through formatted displays
+//! - 🔥 CRITICAL: Perfect mask/character-limit coordination to prevent invisible character bugs
+//!
+//! ⚠️  IMPORTANT BUG PREVENTION:
+//! This example demonstrates the CORRECT way to configure masks with character limits.
+//! Each mask's input position count EXACTLY matches its character limit to prevent
+//! the critical bug where users can type more characters than they can see.
+//!
+//! Run with: cargo run --example validation_3 --features "gui,validation,cursor-style"
+
+// REQUIRE validation, gui and cursor-style features for mask functionality
+#[cfg(not(all(feature = "validation", feature = "gui", feature = "cursor-style")))]
+compile_error!(
+    "This example requires the 'validation', 'gui' and 'cursor-style' features. \
+     Run with: cargo run --example validation_3 --features \"gui,validation,cursor-style\""
+);
+
+use std::io;
+use crossterm::{
+    event::{
+        self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers,
+    },
+    execute,
+    terminal::{
+        disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen,
+    },
+};
+use ratatui::{
+    backend::{Backend, CrosstermBackend},
+    layout::{Constraint, Direction, Layout, Rect},
+    style::{Color, Style},
+    text::{Line, Span},
+    widgets::{Block, Borders, Paragraph, Wrap},
+    Frame, Terminal,
+};
+
+use canvas::{
+    canvas::{
+        gui::render_canvas_default,
+        modes::AppMode,
+        CursorManager,
+    },
+    DataProvider, FormEditor,
+    ValidationConfig, ValidationConfigBuilder, DisplayMask,
+    validation::mask::MaskDisplayMode,
+};
+
+// Enhanced FormEditor wrapper for mask demonstration
+struct MaskDemoFormEditor<D: DataProvider> {
+    editor: FormEditor<D>,
+    debug_message: String,
+    command_buffer: String,
+    validation_enabled: bool,
+    show_raw_data: bool,
+}
+
+impl<D: DataProvider> MaskDemoFormEditor<D> {
+    fn new(data_provider: D) -> Self {
+        let mut editor = FormEditor::new(data_provider);
+        editor.set_validation_enabled(true);
+
+        Self {
+            editor,
+            debug_message: "🎭 Display Mask Demo - Visual formatting with clean business logic!".to_string(),
+            command_buffer: String::new(),
+            validation_enabled: true,
+            show_raw_data: false,
+        }
+    }
+
+    // === COMMAND BUFFER HANDLING ===
+    fn clear_command_buffer(&mut self) { self.command_buffer.clear(); }
+    fn add_to_command_buffer(&mut self, ch: char) { self.command_buffer.push(ch); }
+    fn get_command_buffer(&self) -> &str { &self.command_buffer }
+    fn has_pending_command(&self) -> bool { !self.command_buffer.is_empty() }
+
+    // === MASK CONTROL ===
+    fn toggle_validation(&mut self) {
+        self.validation_enabled = !self.validation_enabled;
+        self.editor.set_validation_enabled(self.validation_enabled);
+        if self.validation_enabled {
+            self.debug_message = "✅ Display Masks ENABLED - See visual formatting in action!".to_string();
+        } else {
+            self.debug_message = "❌ Display Masks DISABLED - Raw text only".to_string();
+        }
+    }
+
+    fn toggle_raw_data_view(&mut self) {
+        self.show_raw_data = !self.show_raw_data;
+        if self.show_raw_data {
+            self.debug_message = "👁️ Showing RAW business data (what's actually stored)".to_string();
+        } else {
+            self.debug_message = "🎭 Showing FORMATTED display (what users see)".to_string();
+        }
+    }
+
+    fn get_current_field_info(&self) -> (String, String, String) {
+        let field_index = self.editor.current_field();
+        let raw_data = self.editor.data_provider().field_value(field_index);
+        let display_data = if self.validation_enabled {
+            self.editor.current_display_text()
+        } else {
+            raw_data.to_string()
+        };
+
+        let mask_info = if let Some(config) = self.editor.validation_state().get_field_config(field_index) {
+            if let Some(mask) = &config.display_mask {
+                format!("Pattern: '{}', Mode: {:?}",
+                       mask.pattern(),
+                       mask.display_mode())
+            } else {
+                "No mask configured".to_string()
+            }
+        } else {
+            "No validation config".to_string()
+        };
+
+        (raw_data.to_string(), display_data, mask_info)
+    }
+
+    // === ENHANCED MOVEMENT WITH MASK AWARENESS ===
+    fn move_left(&mut self) {
+        self.editor.move_left();
+        self.update_cursor_info();
+    }
+
+    fn move_right(&mut self) {
+        self.editor.move_right();
+        self.update_cursor_info();
+    }
+
+    fn move_up(&mut self) {
+        match self.editor.move_up() {
+            Ok(()) => { self.update_field_info(); }
+            Err(e) => { self.debug_message = format!("🚫 Field switch blocked: {}", e); }
+        }
+    }
+
+    fn move_down(&mut self) {
+        match self.editor.move_down() {
+            Ok(()) => { self.update_field_info(); }
+            Err(e) => { self.debug_message = format!("🚫 Field switch blocked: {}", e); }
+        }
+    }
+
+    fn move_line_start(&mut self) {
+        self.editor.move_line_start();
+        self.update_cursor_info();
+    }
+
+    fn move_line_end(&mut self) {
+        self.editor.move_line_end();
+        self.update_cursor_info();
+    }
+
+    fn update_cursor_info(&mut self) {
+        if self.validation_enabled {
+            let raw_pos = self.editor.cursor_position();
+            let display_pos = self.editor.display_cursor_position();
+            if raw_pos != display_pos {
+                self.debug_message = format!("📍 Cursor: Raw pos {} → Display pos {} (mask active)", raw_pos, display_pos);
+            } else {
+                self.debug_message = format!("📍 Cursor at position {} (no mask offset)", raw_pos);
+            }
+        }
+    }
+
+    fn update_field_info(&mut self) {
+        let field_name = self.editor.data_provider().field_name(self.editor.current_field());
+        self.debug_message = format!("📝 Switched to: {}", field_name);
+    }
+
+    // === MODE TRANSITIONS ===
+    fn enter_edit_mode(&mut self) {
+        // Library will automatically update cursor to bar | in insert mode
+        self.editor.enter_edit_mode();
+        self.debug_message = "✏️ INSERT MODE - Cursor: Steady Bar | - Type to see mask formatting in real-time".to_string();
+    }
+
+    fn enter_append_mode(&mut self) {
+        // Library will automatically update cursor to bar | in insert mode
+        self.editor.enter_append_mode();
+        self.debug_message = "✏️ INSERT (append) - Cursor: Steady Bar | - Mask formatting active".to_string();
+    }
+
+    fn exit_edit_mode(&mut self) {
+        // Library will automatically update cursor to block █ in normal mode
+        self.editor.exit_edit_mode();
+        self.debug_message = "🔒 NORMAL MODE - Cursor: Steady Block █ - Press 'r' to see raw data, 'm' for mask info".to_string();
+    }
+
+    fn insert_char(&mut self, ch: char) -> anyhow::Result<()> {
+        let result = self.editor.insert_char(ch);
+        if result.is_ok() {
+            let (raw, display, _) = self.get_current_field_info();
+            if raw != display {
+                self.debug_message = format!("✏️ Added '{}': Raw='{}' Display='{}'", ch, raw, display);
+            } else {
+                self.debug_message = format!("✏️ Added '{}': '{}'", ch, raw);
+            }
+        }
+        Ok(result?)
+    }
+
+    // === DELETE OPERATIONS ===
+    fn delete_backward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_backward();
+        if result.is_ok() {
+            self.debug_message = "⌫ Character deleted".to_string();
+            self.update_cursor_info();
+        }
+        Ok(result?)
+    }
+
+    fn delete_forward(&mut self) -> anyhow::Result<()> {
+        let result = self.editor.delete_forward();
+        if result.is_ok() {
+            self.debug_message = "⌦ Character deleted".to_string();
+            self.update_cursor_info();
+        }
+        Ok(result?)
+    }
+
+    // === DELEGATE TO ORIGINAL EDITOR ===
+    fn current_field(&self) -> usize { self.editor.current_field() }
+    fn cursor_position(&self) -> usize { self.editor.cursor_position() }
+    fn mode(&self) -> AppMode { self.editor.mode() }
+    fn current_text(&self) -> &str {
+        let field_index = self.editor.current_field();
+        self.editor.data_provider().field_value(field_index)
+    }
+    fn data_provider(&self) -> &D { self.editor.data_provider() }
+    fn ui_state(&self) -> &canvas::EditorState { self.editor.ui_state() }
+    fn set_mode(&mut self, mode: AppMode) {
+        // Library automatically updates cursor for the mode
+        self.editor.set_mode(mode);
+    }
+
+    fn next_field(&mut self) {
+        match self.editor.next_field() {
+            Ok(()) => { self.update_field_info(); }
+            Err(e) => { self.debug_message = format!("🚫 Cannot move to next field: {}", e); }
+        }
+    }
+
+    fn prev_field(&mut self) {
+        match self.editor.prev_field() {
+            Ok(()) => { self.update_field_info(); }
+            Err(e) => { self.debug_message = format!("🚫 Cannot move to previous field: {}", e); }
+        }
+    }
+
+    // === STATUS AND DEBUG ===
+    fn set_debug_message(&mut self, msg: String) { self.debug_message = msg; }
+    fn debug_message(&self) -> &str { &self.debug_message }
+
+    fn show_mask_details(&mut self) {
+        let (raw, display, mask_info) = self.get_current_field_info();
+        self.debug_message = format!("🔍 Field {}: {} | Raw: '{}' Display: '{}'",
+                                   self.current_field() + 1, mask_info, raw, display);
+    }
+
+    fn get_mask_status(&self) -> String {
+        if !self.validation_enabled {
+            return "❌ DISABLED".to_string();
+        }
+
+        let field_count = self.editor.data_provider().field_count();
+        let mut mask_count = 0;
+        for i in 0..field_count {
+            if let Some(config) = self.editor.validation_state().get_field_config(i) {
+                if config.display_mask.is_some() {
+                    mask_count += 1;
+                }
+            }
+        }
+
+        format!("🎭 {} MASKS", mask_count)
+    }
+}
+
+// Demo data with comprehensive mask examples
+struct MaskDemoData {
+    fields: Vec<(String, String)>,
+}
+
+impl MaskDemoData {
+    fn new() -> Self {
+        Self {
+            fields: vec![
+                ("📞 Phone (Dynamic)".to_string(), "".to_string()),
+                ("📞 Phone (Template)".to_string(), "".to_string()),
+                ("📅 Date US (MM/DD/YYYY)".to_string(), "".to_string()),
+                ("📅 Date EU (DD.MM.YYYY)".to_string(), "".to_string()),
+                ("📅 Date ISO (YYYY-MM-DD)".to_string(), "".to_string()),
+                ("🏛️ SSN (XXX-XX-XXXX)".to_string(), "".to_string()),
+                ("💳 Credit Card".to_string(), "".to_string()),
+                ("🏢 Employee ID (EMP-####)".to_string(), "".to_string()),
+                ("📦 Product Code (ABC###XYZ)".to_string(), "".to_string()),
+                ("🌈 Custom Separators".to_string(), "".to_string()),
+                ("⭐ Custom Placeholders".to_string(), "".to_string()),
+                ("🎯 Mixed Input Chars".to_string(), "".to_string()),
+            ],
+        }
+    }
+}
+
+impl DataProvider for MaskDemoData {
+    fn field_count(&self) -> usize { self.fields.len() }
+    fn field_name(&self, index: usize) -> &str { &self.fields[index].0 }
+    fn field_value(&self, index: usize) -> &str { &self.fields[index].1 }
+    fn set_field_value(&mut self, index: usize, value: String) { self.fields[index].1 = value; }
+
+    fn validation_config(&self, field_index: usize) -> Option<ValidationConfig> {
+        match field_index {
+            0 => {
+                // 📞 Phone (Dynamic) - FIXED: Perfect mask/limit coordination
+                let phone_mask = DisplayMask::new("(###) ###-####", '#');
+                Some(ValidationConfigBuilder::new()
+                    .with_display_mask(phone_mask)
+                    .with_max_length(10)  // ✅ CRITICAL: Exactly matches 10 input positions
+                    .build())
+            }
+            1 => {
+                // 📞 Phone (Template) - FIXED: Perfect mask/limit coordination
+                let phone_template = DisplayMask::new("(###) ###-####", '#')
+                    .with_template('_');
+                Some(ValidationConfigBuilder::new()
+                    .with_display_mask(phone_template)
+                    .with_max_length(10)  // ✅ CRITICAL: Exactly matches 10 input positions
+                    .build())
+            }
+            2 => {
+                // 📅 Date US (MM/DD/YYYY) - American date format
+                let us_date = DisplayMask::new("##/##/####", '#');
+                Some(ValidationConfig::with_mask(us_date))
+            }
+            3 => {
+                // 📅 Date EU (DD.MM.YYYY) - European date format with dots
+                let eu_date = DisplayMask::new("##.##.####", '#')
+                    .with_template('•');
+                Some(ValidationConfig::with_mask(eu_date))
+            }
+            4 => {
+                // 📅 Date ISO (YYYY-MM-DD) - ISO date format
+                let iso_date = DisplayMask::new("####-##-##", '#')
+                    .with_template('-');
+                Some(ValidationConfig::with_mask(iso_date))
+            }
+            5 => {
+                // 🏛️ SSN using custom input character 'X' - FIXED: Perfect coordination
+                let ssn_mask = DisplayMask::new("XXX-XX-XXXX", 'X');
+                Some(ValidationConfigBuilder::new()
+                    .with_display_mask(ssn_mask)
+                    .with_max_length(9)  // ✅ CRITICAL: Exactly matches 9 input positions
+                    .build())
+            }
+            6 => {
+                // 💳 Credit Card (16 digits with spaces) - FIXED: Perfect coordination
+                let cc_mask = DisplayMask::new("#### #### #### ####", '#')
+                    .with_template('•');
+                Some(ValidationConfigBuilder::new()
+                    .with_display_mask(cc_mask)
+                    .with_max_length(16)  // ✅ CRITICAL: Exactly matches 16 input positions
+                    .build())
+            }
+            7 => {
+                // 🏢 Employee ID with business prefix
+                let emp_id = DisplayMask::new("EMP-####", '#');
+                Some(ValidationConfig::with_mask(emp_id))
+            }
+            8 => {
+                // 📦 Product Code with mixed letters and numbers
+                let product_code = DisplayMask::new("ABC###XYZ", '#');
+                Some(ValidationConfig::with_mask(product_code))
+            }
+            9 => {
+                // 🌈 Custom Separators - Using | and ~ as separators
+                let custom_sep = DisplayMask::new("##|##~####", '#')
+                    .with_template('?');
+                Some(ValidationConfig::with_mask(custom_sep))
+            }
+            10 => {
+                // ⭐ Custom Placeholders - Using different placeholder characters
+                let custom_placeholder = DisplayMask::new("##-##-##", '#')
+                    .with_template('★');
+                Some(ValidationConfig::with_mask(custom_placeholder))
+            }
+            11 => {
+                // 🎯 Mixed Input Characters - Using 'N' for numbers
+                let mixed_input = DisplayMask::new("ID:NNN-NNN", 'N');
+                Some(ValidationConfig::with_mask(mixed_input))
+            }
+            _ => None,
+        }
+    }
+}
+
+// Enhanced key handling with mask-specific commands
+fn handle_key_press(
+    key: KeyCode,
+    modifiers: KeyModifiers,
+    editor: &mut MaskDemoFormEditor<MaskDemoData>,
+) -> anyhow::Result<bool> {
+    let mode = editor.mode();
+
+    // Quit handling
+    if (key == KeyCode::Char('q') && modifiers.contains(KeyModifiers::CONTROL))
+        || (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL))
+        || key == KeyCode::F(10)
+    {
+        return Ok(false);
+    }
+
+    match (mode, key, modifiers) {
+        // === MODE TRANSITIONS ===
+        (AppMode::ReadOnly, KeyCode::Char('i'), _) => {
+            editor.enter_edit_mode();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('a'), _) => {
+            editor.enter_append_mode();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('A'), _) => {
+            editor.move_line_end();
+            editor.enter_edit_mode();
+            editor.clear_command_buffer();
+        }
+
+        // Escape: Exit edit mode
+        (_, KeyCode::Esc, _) => {
+            if mode == AppMode::Edit {
+                editor.exit_edit_mode();
+            } else {
+                editor.clear_command_buffer();
+            }
+        }
+
+        // === MASK SPECIFIC COMMANDS ===
+        (AppMode::ReadOnly, KeyCode::Char('m'), _) => {
+            editor.show_mask_details();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('r'), _) => {
+            editor.toggle_raw_data_view();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::F(1), _) => {
+            editor.toggle_validation();
+        }
+
+        // === MOVEMENT ===
+        (AppMode::ReadOnly, KeyCode::Char('h'), _) | (AppMode::ReadOnly, KeyCode::Left, _) => {
+            editor.move_left();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('l'), _) | (AppMode::ReadOnly, KeyCode::Right, _) => {
+            editor.move_right();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('j'), _) | (AppMode::ReadOnly, KeyCode::Down, _) => {
+            editor.move_down();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('k'), _) | (AppMode::ReadOnly, KeyCode::Up, _) => {
+            editor.move_up();
+            editor.clear_command_buffer();
+        }
+
+        // Line movement
+        (AppMode::ReadOnly, KeyCode::Char('0'), _) => {
+            editor.move_line_start();
+            editor.clear_command_buffer();
+        }
+        (AppMode::ReadOnly, KeyCode::Char('$'), _) => {
+            editor.move_line_end();
+            editor.clear_command_buffer();
+        }
+
+        // === EDIT MODE MOVEMENT ===
+        (AppMode::Edit, KeyCode::Left, _) => { editor.move_left(); }
+        (AppMode::Edit, KeyCode::Right, _) => { editor.move_right(); }
+        (AppMode::Edit, KeyCode::Up, _) => { editor.move_up(); }
+        (AppMode::Edit, KeyCode::Down, _) => { editor.move_down(); }
+
+        // === DELETE OPERATIONS ===
+        (AppMode::Edit, KeyCode::Backspace, _) => { editor.delete_backward()?; }
+        (AppMode::Edit, KeyCode::Delete, _) => { editor.delete_forward()?; }
+
+        // === TAB NAVIGATION ===
+        (_, KeyCode::Tab, _) => { editor.next_field(); }
+        (_, KeyCode::BackTab, _) => { editor.prev_field(); }
+
+        // === CHARACTER INPUT ===
+        (AppMode::Edit, KeyCode::Char(c), m) if !m.contains(KeyModifiers::CONTROL) => {
+            editor.insert_char(c)?;
+        }
+
+        // === DEBUG/INFO COMMANDS ===
+        (AppMode::ReadOnly, KeyCode::Char('?'), _) => {
+            let (raw, display, mask_info) = editor.get_current_field_info();
+            editor.set_debug_message(format!(
+                "Field {}/{}, Cursor {}, {}, Raw: '{}', Display: '{}'",
+                editor.current_field() + 1,
+                editor.data_provider().field_count(),
+                editor.cursor_position(),
+                mask_info,
+                raw,
+                display
+            ));
+        }
+
+        _ => {
+            if editor.has_pending_command() {
+                editor.clear_command_buffer();
+                editor.set_debug_message("Invalid command sequence".to_string());
+            }
+        }
+    }
+
+    Ok(true)
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut editor: MaskDemoFormEditor<MaskDemoData>,
+) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f, &editor))?;
+
+        if let Event::Key(key) = event::read()? {
+            match handle_key_press(key.code, key.modifiers, &mut editor) {
+                Ok(should_continue) => {
+                    if !should_continue {
+                        break;
+                    }
+                }
+                Err(e) => {
+                    editor.set_debug_message(format!("Error: {}", e));
+                }
+            }
+        }
+    }
+
+    Ok(())
+}
+
+fn ui(f: &mut Frame, editor: &MaskDemoFormEditor<MaskDemoData>) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Min(8), Constraint::Length(16)])
+        .split(f.area());
+
+    render_enhanced_canvas(f, chunks[0], editor);
+    render_mask_status(f, chunks[1], editor);
+}
+
+fn render_enhanced_canvas(
+    f: &mut Frame,
+    area: Rect,
+    editor: &MaskDemoFormEditor<MaskDemoData>,
+) {
+    render_canvas_default(f, area, &editor.editor);
+}
+
+fn render_mask_status(
+    f: &mut Frame,
+    area: Rect,
+    editor: &MaskDemoFormEditor<MaskDemoData>,
+) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([
+            Constraint::Length(3), // Status bar
+            Constraint::Length(6), // Data comparison
+            Constraint::Length(7), // Help
+        ])
+        .split(area);
+
+    // Status bar with mask information
+    let mode_text = match editor.mode() {
+        AppMode::Edit => "INSERT | (bar cursor)",
+        AppMode::ReadOnly => "NORMAL █ (block cursor)",
+        _ => "NORMAL █ (block cursor)",
+    };
+
+    let mask_status = editor.get_mask_status();
+    let status_text = format!("-- {} -- {} | Masks: {} | View: {}",
+                             mode_text,
+                             editor.debug_message(),
+                             mask_status,
+                             if editor.show_raw_data { "RAW" } else { "FORMATTED" });
+
+    let status = Paragraph::new(Line::from(Span::raw(status_text)))
+        .block(Block::default().borders(Borders::ALL).title("🎭 Display Mask Demo"));
+
+    f.render_widget(status, chunks[0]);
+
+    // Data comparison showing raw vs display
+    let (raw_data, display_data, mask_info) = editor.get_current_field_info();
+    let field_name = editor.data_provider().field_name(editor.current_field());
+
+    let comparison_text = format!(
+        "📝 Current Field: {}\n\
+         🔧 Mask Config: {}\n\
+         \n\
+         💾 Raw Business Data: '{}' ← What's actually stored in your database\n\
+         🎭 Formatted Display: '{}' ← What users see in the interface\n\
+         📍 Cursor: Raw pos {} → Display pos {}",
+        field_name,
+        mask_info,
+        raw_data,
+        display_data,
+        editor.cursor_position(),
+        editor.editor.display_cursor_position()
+    );
+
+    let comparison_style = if raw_data != display_data {
+        Style::default().fg(Color::Green) // Green when mask is active
+    } else {
+        Style::default().fg(Color::Gray) // Gray when no formatting
+    };
+
+    let data_comparison = Paragraph::new(comparison_text)
+        .block(Block::default().borders(Borders::ALL).title("📊 Raw Data vs Display Formatting"))
+        .style(comparison_style)
+        .wrap(Wrap { trim: true });
+
+    f.render_widget(data_comparison, chunks[1]);
+
+    // Enhanced help text
+    let help_text = match editor.mode() {
+        AppMode::ReadOnly => {
+            "🎯 CURSOR-STYLE: Normal █ | Insert |\n\
+             🎭 MASK DEMO: Visual formatting keeps business logic clean!\n\
+             \n\
+             📱 Try different fields to see various mask patterns:\n\
+             • Dynamic vs Template modes  • Custom separators  • Different input chars\n\
+             \n\
+             Commands: i/a=insert, m=mask details, r=toggle raw/display view\n\
+             Movement: hjkl/arrows=move, 0/$=line start/end, Tab=next field, F1=toggle masks\n\
+             ?=detailed info, Ctrl+C=quit"
+        }
+        AppMode::Edit => {
+            "🎯 INSERT MODE - Cursor: | (bar)\n\
+             ✏️ Type to see real-time mask formatting!\n\
+             \n\
+             🔥 Key Features in Action:\n\
+             • Separators auto-appear as you type  • Cursor skips over separators\n\
+             • Template fields show placeholders  • Raw data stays clean for business logic\n\
+             \n\
+             arrows=move through mask, Backspace/Del=delete, Esc=normal, Tab=next field\n\
+             Notice how cursor position maps between raw data and display!"
+        }
+        _ => "🎭 Display Mask Demo Active!"
+    };
+
+    let help = Paragraph::new(help_text)
+        .block(Block::default().borders(Borders::ALL).title("🚀 Mask Features & Commands"))
+        .style(Style::default().fg(Color::Gray))
+        .wrap(Wrap { trim: true });
+
+    f.render_widget(help, chunks[2]);
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Print feature status
+    println!("🎭 Canvas Display Mask Demo (Feature 3)");
+    println!("✅ validation feature: ENABLED");
+    println!("✅ gui feature: ENABLED");
+    println!("🎭 Display masks: ACTIVE");
+    println!("✅ cursor-style feature: ENABLED");
+    println!("🔥 Key Benefits Demonstrated:");
+    println!("   • Clean separation: Visual formatting ≠ Business logic");
+    println!("   • User-friendly: Pretty displays with automatic cursor handling");
+    println!("   • Flexible: Custom patterns, separators, and placeholders");
+    println!("   • Transparent: Library handles all complexity, API stays simple");
+    println!();
+    println!("💡 Try typing in different fields to see mask magic!");
+    println!("   📞 Phone fields show dynamic vs template modes");
+    println!("   📅 Date fields show different regional formats");
+    println!("   💳 Credit card shows spaced formatting");
+    println!("   ⭐ Custom fields show advanced separator/placeholder options");
+    println!();
+
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    let data = MaskDemoData::new();
+    let mut editor = MaskDemoFormEditor::new(data);
+
+    // Initialize with normal mode - library automatically sets block cursor
+    editor.set_mode(AppMode::ReadOnly);
+
+    // Demonstrate that CursorManager is available and working
+    CursorManager::update_for_mode(AppMode::ReadOnly)?;
+
+    let res = run_app(&mut terminal, editor);
+
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    // Library automatically resets cursor on FormEditor::drop()
+    // But we can also manually reset if needed
+    CursorManager::reset()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err);
+    }
+
+    println!("🎭 Display mask demo completed!");
+    println!("🏆 You've seen how masks provide beautiful UX while keeping business logic clean!");
+    Ok(())
+}
--- a/canvas/examples/validation_4.rs
+++ b/canvas/examples/validation_4.rs
@@ -0,0 +1,755 @@
+/* examples/validation_4.rs
+   Enhanced Feature 4 Demo: Multiple custom formatters with comprehensive edge cases
+
+   Demonstrates:
+   - Multiple formatter types: PSC, Phone, Credit Card, Date
+   - Edge case handling: incomplete input, invalid chars, overflow
+   - Real-time validation feedback and format preview
+   - Advanced cursor position mapping
+   - Raw vs formatted data separation
+   - Error handling and fallback behavior
+
+*/
+
+#![allow(clippy::needless_return)]
+
+#[cfg(not(all(feature = "validation", feature = "gui", feature = "cursor-style")))]
+compile_error!(
+    "This example requires the 'validation', 'gui' and 'cursor-style' features. \
+     Run with: cargo run --example validation_4 --features \"gui,validation,cursor-style\""
+);
+
+use std::io;
+use std::sync::Arc;
+
+use crossterm::{
+    event::{
+        self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers,
+    },
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use ratatui::{
+    backend::{Backend, CrosstermBackend},
+    layout::{Constraint, Direction, Layout, Rect},
+    style::{Color, Style},
+    text::{Line, Span},
+    widgets::{Block, Borders, Paragraph, Wrap},
+    Frame, Terminal,
+};
+
+use canvas::{
+    canvas::{gui::render_canvas_default, modes::AppMode, CursorManager},
+    DataProvider, FormEditor,
+    ValidationConfig, ValidationConfigBuilder,
+    CustomFormatter, FormattingResult,
+};
+
+/// PSC (Postal Code) Formatter: "01001" -> "010 01"
+struct PSCFormatter;
+
+impl CustomFormatter for PSCFormatter {
+    fn format(&self, raw: &str) -> FormattingResult {
+        if raw.is_empty() {
+            return FormattingResult::success("");
+        }
+
+        // Validate: only digits allowed
+        if !raw.chars().all(|c| c.is_ascii_digit()) {
+            return FormattingResult::error("PSC must contain only digits");
+        }
+
+        let len = raw.chars().count();
+        match len {
+            0 => FormattingResult::success(""),
+            1..=3 => FormattingResult::success(raw),
+            4 => FormattingResult::warning(
+                format!("{} ", &raw[..3]),
+                "PSC incomplete (4/5 digits)"
+            ),
+            5 => {
+                let formatted = format!("{} {}", &raw[..3], &raw[3..]);
+                if raw == "00000" {
+                    FormattingResult::warning(formatted, "Invalid PSC: 00000")
+                } else {
+                    FormattingResult::success(formatted)
+                }
+            },
+            _ => FormattingResult::error("PSC too long (max 5 digits)"),
+        }
+    }
+}
+
+/// Phone Number Formatter: "1234567890" -> "(123) 456-7890"
+struct PhoneFormatter;
+
+impl CustomFormatter for PhoneFormatter {
+    fn format(&self, raw: &str) -> FormattingResult {
+        if raw.is_empty() {
+            return FormattingResult::success("");
+        }
+
+        // Only digits allowed
+        if !raw.chars().all(|c| c.is_ascii_digit()) {
+            return FormattingResult::error("Phone must contain only digits");
+        }
+
+        let len = raw.chars().count();
+        match len {
+            0 => FormattingResult::success(""),
+            1..=3 => FormattingResult::success(format!("({})", raw)),
+            4..=6 => FormattingResult::success(format!("({}) {}", &raw[..3], &raw[3..])),
+            7..=10 => FormattingResult::success(format!("({}) {}-{}", &raw[..3], &raw[3..6], &raw[6..])),
+            10 => {
+                let formatted = format!("({}) {}-{}", &raw[..3], &raw[3..6], &raw[6..]);
+                FormattingResult::success(formatted)
+            },
+            _ => FormattingResult::warning(
+                format!("({}) {}-{}", &raw[..3], &raw[3..6], &raw[6..10]),
+                "Phone too long (extra digits ignored)"
+            ),
+        }
+    }
+}
+
+/// Credit Card Formatter: "1234567890123456" -> "1234 5678 9012 3456"
+struct CreditCardFormatter;
+
+impl CustomFormatter for CreditCardFormatter {
+    fn format(&self, raw: &str) -> FormattingResult {
+        if raw.is_empty() {
+            return FormattingResult::success("");
+        }
+
+        if !raw.chars().all(|c| c.is_ascii_digit()) {
+            return FormattingResult::error("Card number must contain only digits");
+        }
+
+        let mut formatted = String::new();
+        for (i, ch) in raw.chars().enumerate() {
+            if i > 0 && i % 4 == 0 {
+                formatted.push(' ');
+            }
+            formatted.push(ch);
+        }
+
+        let len = raw.chars().count();
+        match len {
+            0..=15 => FormattingResult::warning(formatted, format!("Card incomplete ({}/16 digits)", len)),
+            16 => FormattingResult::success(formatted),
+            _ => FormattingResult::warning(formatted, "Card too long (extra digits shown)"),
+        }
+    }
+}
+
+
+
+
+
+
+/// Date Formatter: "12012024" -> "12/01/2024"
+struct DateFormatter;
+
+impl CustomFormatter for DateFormatter {
+    fn format(&self, raw: &str) -> FormattingResult {
+        if raw.is_empty() {
+            return FormattingResult::success("");
+        }
+
+        if !raw.chars().all(|c| c.is_ascii_digit()) {
+            return FormattingResult::error("Date must contain only digits");
+        }
+
+        let len = raw.len();
+        match len {
+            0 => FormattingResult::success(""),
+            1..=2 => FormattingResult::success(raw.to_string()),
+            3..=4 => FormattingResult::success(format!("{}/{}", &raw[..2], &raw[2..])),
+            5..=8 => FormattingResult::success(format!("{}/{}/{}", &raw[..2], &raw[2..4], &raw[4..])),
+            8 => {
+                let month = &raw[..2];
+                let day = &raw[2..4];
+                let year = &raw[4..];
+
+                // Basic validation
+                let m: u32 = month.parse().unwrap_or(0);
+                let d: u32 = day.parse().unwrap_or(0);
+
+                if m == 0 || m > 12 {
+                    FormattingResult::warning(
+                        format!("{}/{}/{}", month, day, year),
+                        "Invalid month (01-12)"
+                    )
+                } else if d == 0 || d > 31 {
+                    FormattingResult::warning(
+                        format!("{}/{}/{}", month, day, year),
+                        "Invalid day (01-31)"
+                    )
+                } else {
+                    FormattingResult::success(format!("{}/{}/{}", month, day, year))
+                }
+            },
+            _ => FormattingResult::error("Date too long (MMDDYYYY format)"),
+        }
+    }
+}
+
+// Enhanced demo data with multiple formatter types
+struct MultiFormatterDemoData {
+    fields: Vec<(String, String)>,
+}
+
+impl MultiFormatterDemoData {
+    fn new() -> Self {
+        Self {
+            fields: vec![
+                ("🏁 PSC (01001)".to_string(), "".to_string()),
+                ("📞 Phone (1234567890)".to_string(), "".to_string()),
+                ("💳 Credit Card (16 digits)".to_string(), "".to_string()),
+                ("📅 Date (12012024)".to_string(), "".to_string()),
+                ("📝 Plain Text".to_string(), "".to_string()),
+            ],
+        }
+    }
+}
+
+impl DataProvider for MultiFormatterDemoData {
+    fn field_count(&self) -> usize {
+        self.fields.len()
+    }
+
+    fn field_name(&self, index: usize) -> &str {
+        &self.fields[index].0
+    }
+
+    fn field_value(&self, index: usize) -> &str {
+        &self.fields[index].1
+    }
+
+    fn set_field_value(&mut self, index: usize, value: String) {
+        self.fields[index].1 = value;
+    }
+
+    #[cfg(feature = "validation")]
+    fn validation_config(&self, field_index: usize) -> Option<ValidationConfig> {
+        match field_index {
+            0 => Some(ValidationConfigBuilder::new()
+                .with_custom_formatter(Arc::new(PSCFormatter))
+                .with_max_length(5)
+                .build()),
+            1 => Some(ValidationConfigBuilder::new()
+                .with_custom_formatter(Arc::new(PhoneFormatter))
+                .with_max_length(12)
+                .build()),
+            2 => Some(ValidationConfigBuilder::new()
+                .with_custom_formatter(Arc::new(CreditCardFormatter))
+                .with_max_length(20)
+                .build()),
+            3 => Some(ValidationConfigBuilder::new()
+                .with_custom_formatter(Arc::new(DateFormatter))
+                .with_max_length(8)
+                .build()),
+            4 => Some(ValidationConfigBuilder::new()
+                .with_custom_formatter(Arc::new(DateFormatter))
+                .with_max_length(8)
+                .build()),
+            _ => None, // Plain text field - no formatter
+        }
+    }
+}
+
+// Enhanced demo editor with comprehensive status tracking
+struct EnhancedDemoEditor<D: DataProvider> {
+    editor: FormEditor<D>,
+    debug_message: String,
+    validation_enabled: bool,
+    show_raw_data: bool,
+    show_cursor_details: bool,
+    example_mode: usize,
+}
+
+impl<D: DataProvider> EnhancedDemoEditor<D> {
+    fn new(data_provider: D) -> Self {
+        let mut editor = FormEditor::new(data_provider);
+        editor.set_validation_enabled(true);
+
+        Self {
+            editor,
+            debug_message: "🧩 Enhanced Custom Formatter Demo - Multiple formatters with rich edge cases!".to_string(),
+            validation_enabled: true,
+            show_raw_data: false,
+            show_cursor_details: false,
+            example_mode: 0,
+        }
+    }
+
+    // Field type detection
+    fn current_field_type(&self) -> &'static str {
+        match self.editor.current_field() {
+            0 => "PSC",
+            1 => "Phone",
+            2 => "Credit Card",
+            3 => "Date",
+            _ => "Plain Text",
+        }
+    }
+
+    fn has_formatter(&self) -> bool {
+        self.editor.current_field() < 5 // First 5 fields have formatters
+    }
+
+    fn get_input_rules(&self) -> &'static str {
+        match self.editor.current_field() {
+            0 => "5 digits only (PSC format)",
+            1 => "10+ digits (US phone format)",
+            2 => "16+ digits (credit card)",
+            3 => "Digits as cents (12345 = $123.45)",
+            4 => "8 digits MMDDYYYY (date format)",
+            _ => "Any text (no formatting)",
+        }
+    }
+
+    fn cycle_example_data(&mut self) {
+        let examples = [
+            // PSC examples
+            vec!["01001", "1234567890", "1234567890123456", "12345", "12012024", "Plain text here"],
+            // Incomplete examples
+            vec!["010", "123", "1234", "123", "1201", "More text"],
+            // Invalid examples (will show error handling)
+            vec!["0abc1", "12a45", "123abc", "abc", "ab01cd", "Special chars!"],
+            // Edge cases
+            vec!["00000", "0000000000", "0000000000000000", "99", "13012024", ""],
+        ];
+
+        self.example_mode = (self.example_mode + 1) % examples.len();
+        let current_examples = &examples[self.example_mode];
+
+        for (i, example) in current_examples.iter().enumerate() {
+            if i < self.editor.data_provider().field_count() {
+                self.editor.data_provider_mut().set_field_value(i, example.to_string());
+            }
+        }
+
+        let mode_names = ["Valid Examples", "Incomplete Input", "Invalid Characters", "Edge Cases"];
+        self.debug_message = format!("📋 Loaded: {}", mode_names[self.example_mode]);
+    }
+
+    // Enhanced status methods
+    fn toggle_validation(&mut self) {
+        self.validation_enabled = !self.validation_enabled;
+        self.editor.set_validation_enabled(self.validation_enabled);
+        self.debug_message = if self.validation_enabled {
+            "✅ Custom Formatters ENABLED".to_string()
+        } else {
+            "❌ Custom Formatters DISABLED".to_string()
+        };
+    }
+
+    fn toggle_raw_data_view(&mut self) {
+        self.show_raw_data = !self.show_raw_data;
+        self.debug_message = if self.show_raw_data {
+            "👁️ Showing RAW data focus".to_string()
+        } else {
+            "✨ Showing FORMATTED display focus".to_string()
+        };
+    }
+
+    fn toggle_cursor_details(&mut self) {
+        self.show_cursor_details = !self.show_cursor_details;
+        self.debug_message = if self.show_cursor_details {
+            "📍 Detailed cursor mapping info ON".to_string()
+        } else {
+            "📍 Detailed cursor mapping info OFF".to_string()
+        };
+    }
+
+    fn get_current_field_analysis(&self) -> (String, String, String, Option<String>) {
+        let field_index = self.editor.current_field();
+        let raw = self.editor.data_provider().field_value(field_index);
+        let display = self.editor.current_display_text();
+
+        let status = if raw == display {
+            if self.has_formatter() {
+                if self.mode() == AppMode::Edit {
+                    "Raw (editing)".to_string()
+                } else {
+                    "No formatting needed".to_string()
+                }
+            } else {
+                "No formatter".to_string()
+            }
+        } else {
+            "Custom formatted".to_string()
+        };
+
+        let warning = if self.validation_enabled && self.has_formatter() {
+            // Check if there are any formatting warnings
+            if raw.len() > 0 {
+                match self.editor.current_field() {
+                    0 if raw.len() < 5 => Some(format!("PSC incomplete: {}/5", raw.len())),
+                    1 if raw.len() < 10 => Some(format!("Phone incomplete: {}/10", raw.len())),
+                    2 if raw.len() < 16 => Some(format!("Card incomplete: {}/16", raw.len())),
+                    4 if raw.len() < 8 => Some(format!("Date incomplete: {}/8", raw.len())),
+                    _ => None,
+                }
+            } else {
+                None
+            }
+        } else {
+            None
+        };
+
+        (raw.to_string(), display, status, warning)
+    }
+
+    // Delegate methods with enhanced feedback
+    fn enter_edit_mode(&mut self) {
+        // Library will automatically update cursor to bar | in insert mode
+        self.editor.enter_edit_mode();
+        let field_type = self.current_field_type();
+        let rules = self.get_input_rules();
+        self.debug_message = format!("✏️ INSERT MODE - Cursor: Steady Bar | - {} - {}", field_type, rules);
+    }
+
+    fn exit_edit_mode(&mut self) {
+        // Library will automatically update cursor to block █ in normal mode
+        self.editor.exit_edit_mode();
+        let (raw, display, _, warning) = self.get_current_field_analysis();
+        if let Some(warn) = warning {
+            self.debug_message = format!("🔒 NORMAL - Cursor: Steady Block █ - {} | ⚠️ {}", self.current_field_type(), warn);
+        } else if raw != display {
+            self.debug_message = format!("🔒 NORMAL - Cursor: Steady Block █ - {} formatted successfully", self.current_field_type());
+        } else {
+            self.debug_message = "🔒 NORMAL MODE - Cursor: Steady Block █".to_string();
+        }
+    }
+
+    fn insert_char(&mut self, ch: char) -> anyhow::Result<()> {
+        let result = self.editor.insert_char(ch);
+        if result.is_ok() {
+            let (raw, display, _, _) = self.get_current_field_analysis();
+            if raw != display && self.validation_enabled {
+                self.debug_message = format!("✏️ '{}' added - Real-time formatting active", ch);
+            } else {
+                self.debug_message = format!("✏️ '{}' added", ch);
+            }
+        }
+        result
+    }
+
+    // Position mapping demo
+    fn show_position_mapping(&mut self) {
+        if !self.has_formatter() {
+            self.debug_message = "📍 No position mapping (plain text field)".to_string();
+            return;
+        }
+
+        let raw_pos = self.editor.cursor_position();
+        let display_pos = self.editor.display_cursor_position();
+        let field_index = self.editor.current_field();
+        let raw = self.editor.data_provider().field_value(field_index);
+        let display = self.editor.current_display_text();
+
+        if raw_pos != display_pos {
+            self.debug_message = format!(
+                "🗺️ Position mapping: Raw[{}]='{}' ↔ Display[{}]='{}'",
+                raw_pos,
+                raw.chars().nth(raw_pos).unwrap_or('∅'),
+                display_pos,
+                display.chars().nth(display_pos).unwrap_or('∅')
+            );
+        } else {
+            self.debug_message = format!("📍 Cursor at position {} (no mapping needed)", raw_pos);
+        }
+    }
+
+    // Delegate remaining methods
+    fn mode(&self) -> AppMode { self.editor.mode() }
+    fn current_field(&self) -> usize { self.editor.current_field() }
+    fn cursor_position(&self) -> usize { self.editor.cursor_position() }
+    fn data_provider(&self) -> &D { self.editor.data_provider() }
+    fn data_provider_mut(&mut self) -> &mut D { self.editor.data_provider_mut() }
+    fn ui_state(&self) -> &canvas::EditorState { self.editor.ui_state() }
+
+    fn move_up(&mut self) { let _ = self.editor.move_up(); }
+    fn move_down(&mut self) { let _ = self.editor.move_down(); }
+    fn move_left(&mut self) { let _ = self.editor.move_left(); }
+    fn move_right(&mut self) { let _ = self.editor.move_right(); }
+    fn delete_backward(&mut self) -> anyhow::Result<()> { self.editor.delete_backward() }
+    fn delete_forward(&mut self) -> anyhow::Result<()> { self.editor.delete_forward() }
+    fn next_field(&mut self) { let _ = self.editor.next_field(); }
+    fn prev_field(&mut self) { let _ = self.editor.prev_field(); }
+}
+
+// Enhanced key handling
+fn handle_key_press(
+    key: KeyCode,
+    modifiers: KeyModifiers,
+    editor: &mut EnhancedDemoEditor<MultiFormatterDemoData>,
+) -> anyhow::Result<bool> {
+    let mode = editor.mode();
+
+    // Quit
+    if matches!(key, KeyCode::F(10)) ||
+       (key == KeyCode::Char('q') && modifiers.contains(KeyModifiers::CONTROL)) ||
+       (key == KeyCode::Char('c') && modifiers.contains(KeyModifiers::CONTROL)) {
+        return Ok(false);
+    }
+
+    match (mode, key, modifiers) {
+        // Mode transitions
+        (AppMode::ReadOnly, KeyCode::Char('i'), _) => editor.enter_edit_mode(),
+        (AppMode::ReadOnly, KeyCode::Char('a'), _) => {
+            editor.editor.enter_append_mode();
+            editor.debug_message = format!("✏️ APPEND {} - {}", editor.current_field_type(), editor.get_input_rules());
+        },
+        (_, KeyCode::Esc, _) => editor.exit_edit_mode(),
+
+        // Enhanced demo features
+        (AppMode::ReadOnly, KeyCode::Char('e'), _) => editor.cycle_example_data(),
+        (AppMode::ReadOnly, KeyCode::Char('r'), _) => editor.toggle_raw_data_view(),
+        (AppMode::ReadOnly, KeyCode::Char('c'), _) => editor.toggle_cursor_details(),
+        (AppMode::ReadOnly, KeyCode::Char('m'), _) => editor.show_position_mapping(),
+        (AppMode::ReadOnly, KeyCode::F(1), _) => editor.toggle_validation(),
+
+        // Movement
+        (_, KeyCode::Up, _) | (AppMode::ReadOnly, KeyCode::Char('k'), _) => editor.move_up(),
+        (_, KeyCode::Down, _) | (AppMode::ReadOnly, KeyCode::Char('j'), _) => editor.move_down(),
+        (_, KeyCode::Left, _) | (AppMode::ReadOnly, KeyCode::Char('h'), _) => editor.move_left(),
+        (_, KeyCode::Right, _) | (AppMode::ReadOnly, KeyCode::Char('l'), _) => editor.move_right(),
+        (_, KeyCode::Tab, _) => editor.next_field(),
+        (_, KeyCode::BackTab, _) => editor.prev_field(),
+
+        // Editing
+        (AppMode::Edit, KeyCode::Char(c), m) if !m.contains(KeyModifiers::CONTROL) => {
+            editor.insert_char(c)?;
+        },
+        (AppMode::Edit, KeyCode::Backspace, _) => { editor.delete_backward()?; },
+        (AppMode::Edit, KeyCode::Delete, _) => { editor.delete_forward()?; },
+
+        // Field analysis
+        (AppMode::ReadOnly, KeyCode::Char('?'), _) => {
+            let (raw, display, status, warning) = editor.get_current_field_analysis();
+            let warning_text = warning.map(|w| format!(" ⚠️ {}", w)).unwrap_or_default();
+            editor.debug_message = format!(
+                "🔍 Field {}: {} | Raw: '{}' | Display: '{}'{}",
+                editor.current_field() + 1, status, raw, display, warning_text
+            );
+        },
+
+        _ => {}
+    }
+
+    Ok(true)
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut editor: EnhancedDemoEditor<MultiFormatterDemoData>,
+) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f, &editor))?;
+
+        if let Event::Key(key) = event::read()? {
+            match handle_key_press(key.code, key.modifiers, &mut editor) {
+                Ok(should_continue) => {
+                    if !should_continue {
+                        break;
+                    }
+                }
+                Err(e) => {
+                    editor.debug_message = format!("❌ Error: {}", e);
+                }
+            }
+        }
+    }
+    Ok(())
+}
+
+fn ui(f: &mut Frame, editor: &EnhancedDemoEditor<MultiFormatterDemoData>) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([Constraint::Min(8), Constraint::Length(18)])
+        .split(f.area());
+
+    render_canvas_default(f, chunks[0], &editor.editor);
+    render_enhanced_status(f, chunks[1], editor);
+}
+
+fn render_enhanced_status(
+    f: &mut Frame,
+    area: Rect,
+    editor: &EnhancedDemoEditor<MultiFormatterDemoData>,
+) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints([
+            Constraint::Length(3),  // Status bar
+            Constraint::Length(6),  // Current field analysis
+            Constraint::Length(9),  // Help
+        ])
+        .split(area);
+
+    // Status bar
+    let mode_text = match editor.mode() {
+        AppMode::Edit => "INSERT | (bar cursor)",
+        AppMode::ReadOnly => "NORMAL █ (block cursor)",
+        _ => "NORMAL █ (block cursor)",
+    };
+
+    let formatter_count = (0..editor.data_provider().field_count())
+        .filter(|&i| editor.data_provider().validation_config(i).is_some())
+        .count();
+
+    let status_text = format!(
+        "-- {} -- {} | Formatters: {}/{} active | View: {}{}",
+        mode_text,
+        editor.debug_message,
+        formatter_count,
+        editor.data_provider().field_count(),
+        if editor.show_raw_data { "RAW" } else { "DISPLAY" },
+        if editor.show_cursor_details { " | CURSOR+" } else { "" }
+    );
+
+    let status = Paragraph::new(Line::from(Span::raw(status_text)))
+        .block(Block::default().borders(Borders::ALL).title("🧩 Enhanced Custom Formatter Demo"));
+
+    f.render_widget(status, chunks[0]);
+
+    // Current field analysis
+    let (raw, display, status, warning) = editor.get_current_field_analysis();
+    let field_name = editor.data_provider().field_name(editor.current_field());
+    let field_type = editor.current_field_type();
+
+    let mut analysis_lines = vec![
+        format!("📝 Current: {} ({})", field_name, field_type),
+        format!("🔧 Status: {}", status),
+    ];
+
+    if editor.show_raw_data || editor.mode() == AppMode::Edit {
+        analysis_lines.push(format!("💾 Raw Data: '{}'", raw));
+        analysis_lines.push(format!("✨ Display: '{}'", display));
+    } else {
+        analysis_lines.push(format!("✨ User Sees: '{}'", display));
+        analysis_lines.push(format!("💾 Stored As: '{}'", raw));
+    }
+
+    if editor.show_cursor_details {
+        analysis_lines.push(format!(
+            "📍 Cursor: Raw[{}] → Display[{}]",
+            editor.cursor_position(),
+            editor.editor.display_cursor_position()
+        ));
+    }
+
+    if let Some(ref warn) = warning {
+        analysis_lines.push(format!("⚠️ Warning: {}", warn));
+    }
+
+    let analysis_color = if warning.is_some() {
+        Color::Yellow
+    } else if raw != display && editor.validation_enabled {
+        Color::Green
+    } else {
+        Color::Gray
+    };
+
+    let analysis = Paragraph::new(analysis_lines.join("\n"))
+        .block(Block::default().borders(Borders::ALL).title("🔍 Field Analysis"))
+        .style(Style::default().fg(analysis_color))
+        .wrap(Wrap { trim: true });
+
+    f.render_widget(analysis, chunks[1]);
+
+    // Enhanced help
+    let help_text = match editor.mode() {
+        AppMode::ReadOnly => {
+            "🎯 CURSOR-STYLE: Normal █ | Insert |\n\
+             🧩 ENHANCED CUSTOM FORMATTER DEMO\n\
+             \n\
+             Try these formatters:
+             • PSC: 01001 → 010 01 | Phone: 1234567890 → (123) 456-7890 | Card: 1234567890123456 → 1234 5678 9012 3456
+             • Date: 12012024 → 12/01/2024 | Plain: no formatting
+             \n\
+             Commands: i=insert, e=cycle examples, r=toggle raw/display, c=cursor details, m=position mapping\n\
+             Movement: hjkl/arrows, Tab=next field, ?=analyze current field, F1=toggle formatters\n\
+             Ctrl+C/F10=quit"
+        }
+        AppMode::Edit => {
+            "🎯 INSERT MODE - Cursor: | (bar)\n\
+             ✏️ Real-time formatting as you type!\n\
+             \n\
+             Current field rules: {}\n\
+             • Raw input is authoritative (what gets stored)\n\
+             • Display formatting updates in real-time (what users see)\n\
+             • Cursor position is mapped between raw and display\n\
+             \n\
+             Esc=normal mode, arrows=navigate, Backspace/Del=delete"
+        }
+        _ => "🧩 Enhanced Custom Formatter Demo"
+    };
+
+    let formatted_help = if editor.mode() == AppMode::Edit {
+        help_text.replace("{}", editor.get_input_rules())
+    } else {
+        help_text.to_string()
+    };
+
+    let help = Paragraph::new(formatted_help)
+        .block(Block::default().borders(Borders::ALL).title("🚀 Enhanced Features & Commands"))
+        .style(Style::default().fg(Color::Gray))
+        .wrap(Wrap { trim: true });
+
+    f.render_widget(help, chunks[2]);
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    println!("🧩 Enhanced Canvas Custom Formatter Demo (Feature 4)");
+    println!("✅ validation feature: ENABLED");
+    println!("✅ gui feature: ENABLED");
+    println!("✅ cursor-style feature: ENABLED");
+    println!("🧩 Enhanced features:");
+    println!("   • 5 different custom formatters with edge cases");
+    println!("   • Real-time format preview and validation");
+    println!("   • Advanced cursor position mapping");
+    println!("   • Comprehensive error handling and warnings");
+    println!("   • Raw vs formatted data separation demos");
+    println!();
+
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    let data = MultiFormatterDemoData::new();
+    let mut editor = EnhancedDemoEditor::new(data);
+
+    // Initialize with normal mode - library automatically sets block cursor
+    editor.editor.set_mode(AppMode::ReadOnly);
+
+    // Demonstrate that CursorManager is available and working
+    CursorManager::update_for_mode(AppMode::ReadOnly)?;
+
+    let res = run_app(&mut terminal, editor);
+
+    disable_raw_mode()?;
+    execute!(terminal.backend_mut(), LeaveAlternateScreen, DisableMouseCapture)?;
+    terminal.show_cursor()?;
+
+    // Library automatically resets cursor on FormEditor::drop()
+    // But we can also manually reset if needed
+    CursorManager::reset()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err);
+    }
+
+    println!("🧩 Enhanced custom formatter demo completed!");
+    println!("🏆 You experienced comprehensive custom formatting with:");
+    println!("   • Multiple formatter types (PSC, Phone, Credit Card, Date)");
+    println!("   • Edge case handling (incomplete, invalid, overflow)");
+    println!("   • Real-time format preview and cursor mapping");
+    println!("   • Clear separation between raw business data and display formatting");
+    Ok(())
+}
--- a/canvas/examples/validation_5.rs
+++ b/canvas/examples/validation_5.rs
--- a/canvas/integration_patterns.rs
+++ b/canvas/integration_patterns.rs
@@ -114,7 +114,7 @@ async fn state_machine_example() {
            }
        }

-        fn handle_feature_action(&mut self, action: &CanvasAction, _context: &ActionContext) -> Option<String> {
+        fn handle_feature_action(&mut self, action: &CanvasAction, context: &ActionContext) -> Option<String> {
            match action {
                CanvasAction::Custom(cmd) => match cmd.as_str() {
                    "submit" => {
@@ -147,7 +147,7 @@ async fn state_machine_example() {
    println!("  Initial state: {:?}", form.state);

    // Type some text to trigger state change
-    let _result = ActionDispatcher::dispatch(
+    let result = ActionDispatcher::dispatch(
        CanvasAction::InsertChar('u'),
        &mut form,
        &mut ideal_cursor,
@@ -231,7 +231,7 @@ async fn event_driven_example() {
            self.has_changes = changed;
        }

-        fn handle_feature_action(&mut self, action: &CanvasAction, _context: &ActionContext) -> Option<String> {
+        fn handle_feature_action(&mut self, action: &CanvasAction, context: &ActionContext) -> Option<String> {
            match action {
                CanvasAction::Custom(cmd) => match cmd.as_str() {
                    "validate" => {
@@ -384,7 +384,7 @@ async fn validation_pipeline_example() {
        fn has_unsaved_changes(&self) -> bool { self.has_changes }
        fn set_has_unsaved_changes(&mut self, changed: bool) { self.has_changes = changed; }

-        fn handle_feature_action(&mut self, action: &CanvasAction, _context: &ActionContext) -> Option<String> {
+        fn handle_feature_action(&mut self, action: &CanvasAction, context: &ActionContext) -> Option<String> {
            match action {
                CanvasAction::Custom(cmd) => match cmd.as_str() {
                    "validate" => {
--- a/canvas/src/autocomplete/actions.rs
+++ b/canvas/src/autocomplete/actions.rs
@@ -1,170 +0,0 @@
-// src/autocomplete/actions.rs
-
-use crate::canvas::state::CanvasState;
-use crate::autocomplete::state::AutocompleteCanvasState;
-use crate::canvas::actions::types::{CanvasAction, ActionResult};
-use crate::canvas::actions::execute;
-use anyhow::Result;
-
-/// Enhanced execute function for states that support autocomplete
-/// This is the main entry point for autocomplete-aware canvas execution
-///
-/// Use this instead of canvas::execute() if you want autocomplete behavior:
-/// ```rust
-/// execute_with_autocomplete(action, &mut state).await?;
-/// ```
-pub async fn execute_with_autocomplete<S: CanvasState + AutocompleteCanvasState + Send>(
-    action: CanvasAction,
-    state: &mut S,
-) -> Result<ActionResult> {
-    match &action {
-        // === AUTOCOMPLETE-SPECIFIC ACTIONS ===
-
-        CanvasAction::TriggerAutocomplete => {
-            if state.supports_autocomplete(state.current_field()) {
-                state.trigger_autocomplete_suggestions().await;
-                Ok(ActionResult::success_with_message("Triggered autocomplete"))
-            } else {
-                Ok(ActionResult::success_with_message("Autocomplete not supported for this field"))
-            }
-        }
-
-        CanvasAction::SuggestionUp => {
-            if state.has_autocomplete_suggestions() {
-                state.move_suggestion_selection(-1);
-                Ok(ActionResult::success())
-            } else {
-                Ok(ActionResult::success_with_message("No suggestions available"))
-            }
-        }
-
-        CanvasAction::SuggestionDown => {
-            if state.has_autocomplete_suggestions() {
-                state.move_suggestion_selection(1);
-                Ok(ActionResult::success())
-            } else {
-                Ok(ActionResult::success_with_message("No suggestions available"))
-            }
-        }
-
-        CanvasAction::SelectSuggestion => {
-            if let Some(message) = state.apply_selected_suggestion() {
-                Ok(ActionResult::success_with_message(&message))
-            } else {
-                Ok(ActionResult::success_with_message("No suggestion to select"))
-            }
-        }
-
-        CanvasAction::ExitSuggestions => {
-            state.clear_autocomplete_suggestions();
-            Ok(ActionResult::success_with_message("Closed autocomplete"))
-        }
-
-        // === TEXT INSERTION WITH AUTO-TRIGGER ===
-
-        CanvasAction::InsertChar(_) => {
-            // First, execute the character insertion normally
-            let result = execute(action, state).await?;
-
-            // After successful insertion, check if we should auto-trigger autocomplete
-            if result.is_success() && state.should_trigger_autocomplete() {
-                state.trigger_autocomplete_suggestions().await;
-            }
-
-            Ok(result)
-        }
-
-        // === NAVIGATION/EDITING ACTIONS (clear autocomplete first) ===
-
-        CanvasAction::MoveLeft | CanvasAction::MoveRight |
-        CanvasAction::MoveUp | CanvasAction::MoveDown |
-        CanvasAction::NextField | CanvasAction::PrevField |
-        CanvasAction::DeleteBackward | CanvasAction::DeleteForward => {
-            // Clear autocomplete when navigating/editing
-            if state.is_autocomplete_active() {
-                state.clear_autocomplete_suggestions();
-            }
-
-            // Execute the action normally
-            execute(action, state).await
-        }
-
-        // === ALL OTHER ACTIONS (normal execution) ===
-
-        _ => {
-            // For all other actions, just execute normally
-            execute(action, state).await
-        }
-    }
-}
-
-/// Helper function to integrate autocomplete actions with CanvasState.handle_feature_action()
-///
-/// Use this in your CanvasState implementation like this:
-/// ```rust
-/// fn handle_feature_action(&mut self, action: &CanvasAction, context: &ActionContext) -> Option<String> {
-///     // Try autocomplete first
-///     if let Some(result) = handle_autocomplete_feature_action(action, self) {
-///         return Some(result);
-///     }
-///
-///     // Handle your other custom actions...
-///     None
-/// }
-/// ```
-pub fn handle_autocomplete_feature_action<S: CanvasState + AutocompleteCanvasState + Send>(
-    action: &CanvasAction,
-    state: &S,
-) -> Option<String> {
-    match action {
-        CanvasAction::TriggerAutocomplete => {
-            if state.supports_autocomplete(state.current_field()) {
-                if state.is_autocomplete_active() {
-                    Some("Autocomplete already active".to_string())
-                } else {
-                    None // Let execute_with_autocomplete handle it
-                }
-            } else {
-                Some("Autocomplete not available for this field".to_string())
-            }
-        }
-
-        CanvasAction::SuggestionUp | CanvasAction::SuggestionDown => {
-            if state.is_autocomplete_active() {
-                None // Let execute_with_autocomplete handle navigation
-            } else {
-                Some("No autocomplete suggestions to navigate".to_string())
-            }
-        }
-
-        CanvasAction::SelectSuggestion => {
-            if state.has_autocomplete_suggestions() {
-                None // Let execute_with_autocomplete handle selection
-            } else {
-                Some("No suggestion to select".to_string())
-            }
-        }
-
-        CanvasAction::ExitSuggestions => {
-            if state.is_autocomplete_active() {
-                None // Let execute_with_autocomplete handle exit
-            } else {
-                Some("No autocomplete to close".to_string())
-            }
-        }
-
-        _ => None // Not an autocomplete action
-    }
-}
-
-/// Legacy compatibility function - kept for backward compatibility
-/// This is the old function signature, now it just wraps the new system
-#[deprecated(note = "Use execute_with_autocomplete instead")]
-pub async fn execute_canvas_action_with_autocomplete<S: CanvasState + AutocompleteCanvasState + Send>(
-    action: CanvasAction,
-    state: &mut S,
-    _ideal_cursor_column: &mut usize, // Ignored - new system manages this internally
-    _config: Option<&()>, // Ignored - no more config system
-) -> Result<ActionResult> {
-    execute_with_autocomplete(action, state).await
-}
--- a/canvas/src/autocomplete/mod.rs
+++ b/canvas/src/autocomplete/mod.rs
@@ -1,22 +0,0 @@
-// src/autocomplete/mod.rs
-
-pub mod types;
-pub mod state;
-pub mod actions;
-
-#[cfg(feature = "gui")]
-pub mod gui;
-
-// Re-export the main autocomplete API
-pub use types::{SuggestionItem, AutocompleteState};
-pub use state::AutocompleteCanvasState;
-
-// Re-export the new action functions
-pub use actions::{
-    execute_with_autocomplete,
-    handle_autocomplete_feature_action,
-};
-
-// Re-export GUI functions if available
-#[cfg(feature = "gui")]
-pub use gui::render_autocomplete_dropdown;
--- a/canvas/src/autocomplete/state.rs
+++ b/canvas/src/autocomplete/state.rs
@@ -1,189 +0,0 @@
-// src/autocomplete/state.rs
-
-use crate::canvas::state::CanvasState;
-use async_trait::async_trait;
-
-/// OPTIONAL extension trait for states that want rich autocomplete functionality.
-/// Only implement this if you need the new autocomplete features.
-///
-/// # User Workflow:
-/// 1. User presses trigger key (Tab, Ctrl+K, etc.)
-/// 2. User's key mapping calls CanvasAction::TriggerAutocomplete
-/// 3. Library calls your trigger_autocomplete_suggestions() method
-/// 4. You implement async fetching logic in that method
-/// 5. You call set_autocomplete_suggestions() with results
-/// 6. Library manages UI state and navigation
-#[async_trait]
-pub trait AutocompleteCanvasState: CanvasState {
-    /// Associated type for suggestion data (e.g., Hit, String, CustomType)
-    type SuggestionData: Clone + Send + 'static;
-
-    /// Check if a field supports autocomplete (user decides which fields)
-    fn supports_autocomplete(&self, _field_index: usize) -> bool {
-        false // Default: no autocomplete support
-    }
-
-    /// Get autocomplete state (read-only)
-    fn autocomplete_state(&self) -> Option<&crate::autocomplete::AutocompleteState<Self::SuggestionData>> {
-        None // Default: no autocomplete state
-    }
-
-    /// Get autocomplete state (mutable)
-    fn autocomplete_state_mut(&mut self) -> Option<&mut crate::autocomplete::AutocompleteState<Self::SuggestionData>> {
-        None // Default: no autocomplete state
-    }
-
-    // === PUBLIC API METHODS (called by library) ===
-
-    /// Activate autocomplete for current field (shows loading spinner)
-    fn activate_autocomplete(&mut self) {
-        let current_field = self.current_field();
-        if let Some(state) = self.autocomplete_state_mut() {
-            state.activate(current_field);
-        }
-    }
-
-    /// Deactivate autocomplete (hides dropdown)
-    fn deactivate_autocomplete(&mut self) {
-        if let Some(state) = self.autocomplete_state_mut() {
-            state.deactivate();
-        }
-    }
-
-    /// Set suggestions (called after your async fetch completes)
-    fn set_autocomplete_suggestions(&mut self, suggestions: Vec<crate::autocomplete::SuggestionItem<Self::SuggestionData>>) {
-        if let Some(state) = self.autocomplete_state_mut() {
-            state.set_suggestions(suggestions);
-        }
-    }
-
-    /// Set loading state (show/hide spinner)
-    fn set_autocomplete_loading(&mut self, loading: bool) {
-        if let Some(state) = self.autocomplete_state_mut() {
-            state.is_loading = loading;
-        }
-    }
-
-    // === QUERY METHODS ===
-
-    /// Check if autocomplete is currently active/visible
-    fn is_autocomplete_active(&self) -> bool {
-        self.autocomplete_state()
-            .map(|state| state.is_active)
-            .unwrap_or(false)
-    }
-
-    /// Check if autocomplete has suggestions ready for navigation
-    fn is_autocomplete_ready(&self) -> bool {
-        self.autocomplete_state()
-            .map(|state| state.is_ready())
-            .unwrap_or(false)
-    }
-
-    /// Check if there are available suggestions
-    fn has_autocomplete_suggestions(&self) -> bool {
-        self.autocomplete_state()
-            .map(|state| !state.suggestions.is_empty())
-            .unwrap_or(false)
-    }
-
-    // === USER-IMPLEMENTABLE METHODS ===
-
-    /// Check if autocomplete should be triggered automatically (e.g., after typing 2+ chars)
-    /// Override this to implement your own trigger logic
-    fn should_trigger_autocomplete(&self) -> bool {
-        let current_input = self.get_current_input();
-        let current_field = self.current_field();
-
-        self.supports_autocomplete(current_field) &&
-        current_input.len() >= 2 && // Default: trigger after 2 chars
-        !self.is_autocomplete_active()
-    }
-
-    /// **USER MUST IMPLEMENT**: Trigger autocomplete suggestions (async)
-    /// This is where you implement your API calls, caching, etc.
-    ///
-    /// # Example Implementation:
-    /// ```rust
-    /// #[async_trait]
-    /// impl AutocompleteCanvasState for MyState {
-    ///     type SuggestionData = MyData;
-    ///     
-    ///     async fn trigger_autocomplete_suggestions(&mut self) {
-    ///         self.activate_autocomplete(); // Show loading state
-    ///
-    ///         let query = self.get_current_input().to_string();
-    ///         let suggestions = my_api.search(&query).await.unwrap_or_default();
-    ///
-    ///         self.set_autocomplete_suggestions(suggestions);
-    ///     }
-    /// }
-    /// ```
-    async fn trigger_autocomplete_suggestions(&mut self) {
-        // Activate autocomplete UI
-        self.activate_autocomplete();
-
-        // Default: just show loading state
-        // User should override this to do actual async fetching
-        self.set_autocomplete_loading(true);
-
-        // In a real implementation, you'd:
-        // 1. Get current input: let query = self.get_current_input();
-        // 2. Make API call: let results = api.search(query).await;
-        // 3. Convert to suggestions: let suggestions = results.into_suggestions();
-        // 4. Set suggestions: self.set_autocomplete_suggestions(suggestions);
-    }
-
-    // === INTERNAL NAVIGATION METHODS (called by library actions) ===
-
-    /// Clear autocomplete suggestions and hide dropdown
-    fn clear_autocomplete_suggestions(&mut self) {
-        self.deactivate_autocomplete();
-    }
-
-    /// Move selection up/down in suggestions list
-    fn move_suggestion_selection(&mut self, direction: i32) {
-        if let Some(state) = self.autocomplete_state_mut() {
-            if direction > 0 {
-                state.select_next();
-            } else {
-                state.select_previous();
-            }
-        }
-    }
-
-    /// Get currently selected suggestion for display/application
-    fn get_selected_suggestion(&self) -> Option<crate::autocomplete::SuggestionItem<Self::SuggestionData>> {
-        self.autocomplete_state()?
-            .get_selected()
-            .cloned()
-    }
-
-    /// Apply the selected suggestion to the current field
-    fn apply_suggestion(&mut self, suggestion: &crate::autocomplete::SuggestionItem<Self::SuggestionData>) {
-        // Apply the value to current field
-        *self.get_current_input_mut() = suggestion.value_to_store.clone();
-        self.set_has_unsaved_changes(true);
-
-        // Clear autocomplete
-        self.clear_autocomplete_suggestions();
-    }
-
-    /// Apply the currently selected suggestion (convenience method)
-    fn apply_selected_suggestion(&mut self) -> Option<String> {
-        if let Some(suggestion) = self.get_selected_suggestion() {
-            let display_text = suggestion.display_text.clone();
-            self.apply_suggestion(&suggestion);
-            Some(format!("Applied: {}", display_text))
-        } else {
-            None
-        }
-    }
-
-    // === LEGACY COMPATIBILITY ===
-
-    /// INTERNAL: Apply selected autocomplete value to current field (legacy method)
-    fn apply_autocomplete_selection(&mut self) -> Option<String> {
-        self.apply_selected_suggestion()
-    }
-}
--- a/canvas/src/autocomplete/types.rs
+++ b/canvas/src/autocomplete/types.rs
@@ -1,126 +0,0 @@
-// canvas/src/autocomplete.rs
-
-/// Generic suggestion item that clients push to canvas
-#[derive(Debug, Clone)]
-pub struct SuggestionItem<T> {
-    /// The underlying data (client-specific, e.g., Hit, String, etc.)
-    pub data: T,
-    /// Text to display in the dropdown
-    pub display_text: String,
-    /// Value to store in the form field when selected
-    pub value_to_store: String,
-}
-
-impl<T> SuggestionItem<T> {
-    pub fn new(data: T, display_text: String, value_to_store: String) -> Self {
-        Self {
-            data,
-            display_text,
-            value_to_store,
-        }
-    }
-    
-    /// Convenience constructor for simple string suggestions
-    pub fn simple(data: T, text: String) -> Self {
-        Self {
-            data,
-            display_text: text.clone(),
-            value_to_store: text,
-        }
-    }
-}
-
-/// Autocomplete state managed by canvas
-#[derive(Debug, Clone)]
-pub struct AutocompleteState<T> {
-    /// Whether autocomplete is currently active/visible
-    pub is_active: bool,
-    /// Whether suggestions are being loaded (for spinner/loading indicator)
-    pub is_loading: bool,
-    /// Current suggestions to display
-    pub suggestions: Vec<SuggestionItem<T>>,
-    /// Currently selected suggestion index
-    pub selected_index: Option<usize>,
-    /// Field index that triggered autocomplete (for context)
-    pub active_field: Option<usize>,
-}
-
-impl<T> Default for AutocompleteState<T> {
-    fn default() -> Self {
-        Self {
-            is_active: false,
-            is_loading: false,
-            suggestions: Vec::new(),
-            selected_index: None,
-            active_field: None,
-        }
-    }
-}
-
-impl<T> AutocompleteState<T> {
-    pub fn new() -> Self {
-        Self::default()
-    }
-    
-    /// Activate autocomplete for a specific field
-    pub fn activate(&mut self, field_index: usize) {
-        self.is_active = true;
-        self.active_field = Some(field_index);
-        self.selected_index = None;
-        self.suggestions.clear();
-        self.is_loading = true;
-    }
-    
-    /// Deactivate autocomplete and clear state
-    pub fn deactivate(&mut self) {
-        self.is_active = false;
-        self.is_loading = false;
-        self.suggestions.clear();
-        self.selected_index = None;
-        self.active_field = None;
-    }
-    
-    /// Set suggestions and stop loading
-    pub fn set_suggestions(&mut self, suggestions: Vec<SuggestionItem<T>>) {
-        self.suggestions = suggestions;
-        self.is_loading = false;
-        self.selected_index = if self.suggestions.is_empty() { 
-            None 
-        } else { 
-            Some(0) 
-        };
-    }
-    
-    /// Move selection down
-    pub fn select_next(&mut self) {
-        if !self.suggestions.is_empty() {
-            let current = self.selected_index.unwrap_or(0);
-            self.selected_index = Some((current + 1) % self.suggestions.len());
-        }
-    }
-    
-    /// Move selection up
-    pub fn select_previous(&mut self) {
-        if !self.suggestions.is_empty() {
-            let current = self.selected_index.unwrap_or(0);
-            self.selected_index = Some(
-                if current == 0 { 
-                    self.suggestions.len() - 1 
-                } else { 
-                    current - 1 
-                }
-            );
-        }
-    }
-    
-    /// Get currently selected suggestion
-    pub fn get_selected(&self) -> Option<&SuggestionItem<T>> {
-        self.selected_index
-            .and_then(|idx| self.suggestions.get(idx))
-    }
-    
-    /// Check if autocomplete is ready for interaction (active and has suggestions)
-    pub fn is_ready(&self) -> bool {
-        self.is_active && !self.suggestions.is_empty() && !self.is_loading
-    }
-}
--- a/canvas/src/canvas/actions/handlers/dispatcher.rs
+++ b/canvas/src/canvas/actions/handlers/dispatcher.rs
@@ -1,43 +0,0 @@
-// src/canvas/actions/handlers/dispatcher.rs
-
-use crate::canvas::state::{CanvasState, ActionContext};
-use crate::canvas::actions::{CanvasAction, ActionResult};
-use crate::canvas::modes::AppMode;
-use anyhow::Result;
-
-use super::{handle_edit_action, handle_readonly_action, handle_highlight_action};
-
-/// Main action dispatcher - routes actions to mode-specific handlers
-pub async fn dispatch_action<S: CanvasState>(
-    action: CanvasAction,
-    state: &mut S,
-    ideal_cursor_column: &mut usize,
-) -> Result<ActionResult> {
-    // Check if the application wants to handle this action first
-    let context = ActionContext {
-        key_code: None,
-        ideal_cursor_column: *ideal_cursor_column,
-        current_input: state.get_current_input().to_string(),
-        current_field: state.current_field(),
-    };
-
-    if let Some(result) = state.handle_feature_action(&action, &context) {
-        return Ok(ActionResult::HandledByFeature(result));
-    }
-
-    // Route to mode-specific handler
-    match state.current_mode() {
-        AppMode::Edit => {
-            handle_edit_action(action, state, ideal_cursor_column).await
-        }
-        AppMode::ReadOnly => {
-            handle_readonly_action(action, state, ideal_cursor_column).await
-        }
-        AppMode::Highlight => {
-            handle_highlight_action(action, state, ideal_cursor_column).await
-        }
-        AppMode::General | AppMode::Command => {
-            Ok(ActionResult::success_with_message("Mode does not handle canvas actions directly"))
-        }
-    }
-}
--- a/canvas/src/canvas/actions/handlers/edit.rs
+++ b/canvas/src/canvas/actions/handlers/edit.rs
@@ -1,213 +0,0 @@
-// src/canvas/actions/handlers/edit.rs
-//! Edit mode action handler
-//!
-//! Handles user input when in edit mode, supporting text entry, deletion,
-//! and cursor movement with edit-specific behavior (cursor can go past end of text).
-
-use crate::canvas::actions::types::{CanvasAction, ActionResult};
-use crate::canvas::actions::movement::*;
-use crate::canvas::state::CanvasState;
-use anyhow::Result;
-
-/// Edit mode uses cursor-past-end behavior for text insertion
-const FOR_EDIT_MODE: bool = true;
-
-/// Handle actions in edit mode with edit-specific cursor behavior
-///
-/// Edit mode allows text modification and uses cursor positioning that can
-/// go past the end of existing text to facilitate insertion.
-///
-/// # Arguments
-/// * `action` - The action to perform
-/// * `state` - Mutable canvas state
-/// * `ideal_cursor_column` - Desired column for vertical movement (maintained across line changes)
-pub async fn handle_edit_action<S: CanvasState>(
-    action: CanvasAction,
-    state: &mut S,
-    ideal_cursor_column: &mut usize,
-) -> Result<ActionResult> {
-    match action {
-        CanvasAction::InsertChar(c) => {
-            // Insert character at cursor position and advance cursor
-            let cursor_pos = state.current_cursor_pos();
-            let input = state.get_current_input_mut();
-            input.insert(cursor_pos, c);
-            state.set_current_cursor_pos(cursor_pos + 1);
-            state.set_has_unsaved_changes(true);
-            *ideal_cursor_column = cursor_pos + 1;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::DeleteBackward => {
-            // Delete character before cursor (Backspace behavior)
-            let cursor_pos = state.current_cursor_pos();
-            if cursor_pos > 0 {
-                let input = state.get_current_input_mut();
-                input.remove(cursor_pos - 1);
-                state.set_current_cursor_pos(cursor_pos - 1);
-                state.set_has_unsaved_changes(true);
-                *ideal_cursor_column = cursor_pos - 1;
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::DeleteForward => {
-            // Delete character at cursor position (Delete key behavior)
-            let cursor_pos = state.current_cursor_pos();
-            let input = state.get_current_input_mut();
-            if cursor_pos < input.len() {
-                input.remove(cursor_pos);
-                state.set_has_unsaved_changes(true);
-            }
-            Ok(ActionResult::success())
-        }
-
-        // Cursor movement actions
-        CanvasAction::MoveLeft => {
-            let new_pos = move_left(state.current_cursor_pos());
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveRight => {
-            let current_input = state.get_current_input();
-            let current_pos = state.current_cursor_pos();
-            let new_pos = move_right(current_pos, current_input, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        // Field navigation (treating single-line fields as "lines")
-        CanvasAction::MoveUp => {
-            let current_field = state.current_field();
-            if current_field > 0 {
-                state.set_current_field(current_field - 1);
-                let current_input = state.get_current_input();
-                let new_pos = safe_cursor_position(current_input, *ideal_cursor_column, FOR_EDIT_MODE);
-                state.set_current_cursor_pos(new_pos);
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveDown => {
-            let current_field = state.current_field();
-            let total_fields = state.fields().len();
-            if current_field < total_fields - 1 {
-                state.set_current_field(current_field + 1);
-                let current_input = state.get_current_input();
-                let new_pos = safe_cursor_position(current_input, *ideal_cursor_column, FOR_EDIT_MODE);
-                state.set_current_cursor_pos(new_pos);
-            }
-            Ok(ActionResult::success())
-        }
-
-        // Line-based movement
-        CanvasAction::MoveLineStart => {
-            let new_pos = line_start_position();
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveLineEnd => {
-            let current_input = state.get_current_input();
-            let new_pos = line_end_position(current_input, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        // Document-level movement (first/last field)
-        CanvasAction::MoveFirstLine => {
-            state.set_current_field(0);
-            let current_input = state.get_current_input();
-            let new_pos = safe_cursor_position(current_input, 0, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveLastLine => {
-            let last_field = state.fields().len() - 1;
-            state.set_current_field(last_field);
-            let current_input = state.get_current_input();
-            let new_pos = line_end_position(current_input, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        // Word-based movement
-        CanvasAction::MoveWordNext => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_next_word_start(current_input, state.current_cursor_pos());
-                state.set_current_cursor_pos(new_pos);
-                *ideal_cursor_column = new_pos;
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordEnd => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_word_end(current_input, state.current_cursor_pos());
-                state.set_current_cursor_pos(new_pos);
-                *ideal_cursor_column = new_pos;
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordPrev => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_prev_word_start(current_input, state.current_cursor_pos());
-                state.set_current_cursor_pos(new_pos);
-                *ideal_cursor_column = new_pos;
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordEndPrev => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_prev_word_end(current_input, state.current_cursor_pos());
-                state.set_current_cursor_pos(new_pos);
-                *ideal_cursor_column = new_pos;
-            }
-            Ok(ActionResult::success())
-        }
-
-        // Field navigation with simple wrapping behavior
-        CanvasAction::NextField | CanvasAction::PrevField => {
-            let current_field = state.current_field();
-            let total_fields = state.fields().len();
-
-            let new_field = match action {
-                CanvasAction::NextField => {
-                    (current_field + 1) % total_fields // Simple wrap
-                }
-                CanvasAction::PrevField => {
-                    if current_field == 0 { total_fields - 1 } else { current_field - 1 } // Simple wrap
-                }
-                _ => unreachable!(),
-            };
-
-            state.set_current_field(new_field);
-            let current_input = state.get_current_input();
-            let new_pos = safe_cursor_position(current_input, *ideal_cursor_column, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::Custom(action_str) => {
-            Ok(ActionResult::success_with_message(&format!("Custom edit action: {}", action_str)))
-        }
-
-        _ => {
-            Ok(ActionResult::success_with_message("Action not implemented for edit mode"))
-        }
-    }
-}
--- a/canvas/src/canvas/actions/handlers/highlight.rs
+++ b/canvas/src/canvas/actions/handlers/highlight.rs
@@ -1,104 +0,0 @@
-// src/canvas/actions/handlers/highlight.rs
-
-use crate::canvas::actions::types::{CanvasAction, ActionResult};
-use crate::canvas::actions::movement::*;
-use crate::canvas::state::CanvasState;
-use anyhow::Result;
-
-const FOR_EDIT_MODE: bool = false; // Highlight mode uses read-only cursor behavior
-
-/// Handle actions in highlight/visual mode
-/// TODO: Implement selection logic and highlight-specific behaviors
-pub async fn handle_highlight_action<S: CanvasState>(
-    action: CanvasAction,
-    state: &mut S,
-    ideal_cursor_column: &mut usize,
-) -> Result<ActionResult> {
-    match action {
-        // Movement actions work similar to read-only mode but with selection
-        CanvasAction::MoveLeft => {
-            let new_pos = move_left(state.current_cursor_pos());
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            // TODO: Update selection range
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveRight => {
-            let current_input = state.get_current_input();
-            let current_pos = state.current_cursor_pos();
-            let new_pos = move_right(current_pos, current_input, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            // TODO: Update selection range
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordNext => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_next_word_start(current_input, state.current_cursor_pos());
-                let final_pos = clamp_cursor_position(new_pos, current_input, FOR_EDIT_MODE);
-                state.set_current_cursor_pos(final_pos);
-                *ideal_cursor_column = final_pos;
-                // TODO: Update selection range
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordEnd => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_word_end(current_input, state.current_cursor_pos());
-                let final_pos = clamp_cursor_position(new_pos, current_input, FOR_EDIT_MODE);
-                state.set_current_cursor_pos(final_pos);
-                *ideal_cursor_column = final_pos;
-                // TODO: Update selection range
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordPrev => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_prev_word_start(current_input, state.current_cursor_pos());
-                state.set_current_cursor_pos(new_pos);
-                *ideal_cursor_column = new_pos;
-                // TODO: Update selection range
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveLineStart => {
-            let new_pos = line_start_position();
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            // TODO: Update selection range
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveLineEnd => {
-            let current_input = state.get_current_input();
-            let new_pos = line_end_position(current_input, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            // TODO: Update selection range
-            Ok(ActionResult::success())
-        }
-
-        // Highlight mode doesn't handle editing actions
-        CanvasAction::InsertChar(_) |
-        CanvasAction::DeleteBackward |
-        CanvasAction::DeleteForward => {
-            Ok(ActionResult::success_with_message("Action not available in highlight mode"))
-        }
-
-        CanvasAction::Custom(action_str) => {
-            Ok(ActionResult::success_with_message(&format!("Custom highlight action: {}", action_str)))
-        }
-
-        _ => {
-            Ok(ActionResult::success_with_message("Action not implemented for highlight mode"))
-        }
-    }
-}
--- a/canvas/src/canvas/actions/handlers/mod.rs
+++ b/canvas/src/canvas/actions/handlers/mod.rs
@@ -1,11 +0,0 @@
-// src/canvas/actions/handlers/mod.rs
-
-pub mod edit;
-pub mod readonly;
-pub mod highlight;
-pub mod dispatcher;
-
-pub use edit::handle_edit_action;
-pub use readonly::handle_readonly_action;
-pub use highlight::handle_highlight_action;
-pub use dispatcher::dispatch_action;
--- a/canvas/src/canvas/actions/handlers/readonly.rs
+++ b/canvas/src/canvas/actions/handlers/readonly.rs
@@ -1,183 +0,0 @@
-// src/canvas/actions/handlers/readonly.rs
-
-use crate::canvas::actions::types::{CanvasAction, ActionResult};
-use crate::canvas::actions::movement::*;
-use crate::canvas::state::CanvasState;
-use anyhow::Result;
-
-const FOR_EDIT_MODE: bool = false; // Read-only mode flag
-
-/// Handle actions in read-only mode with read-only specific cursor behavior
-pub async fn handle_readonly_action<S: CanvasState>(
-    action: CanvasAction,
-    state: &mut S,
-    ideal_cursor_column: &mut usize,
-) -> Result<ActionResult> {
-    match action {
-        CanvasAction::MoveLeft => {
-            let new_pos = move_left(state.current_cursor_pos());
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveRight => {
-            let current_input = state.get_current_input();
-            let current_pos = state.current_cursor_pos();
-            let new_pos = move_right(current_pos, current_input, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveUp => {
-            let current_field = state.current_field();
-            let new_field = current_field.saturating_sub(1);
-            state.set_current_field(new_field);
-
-            // Apply ideal cursor column with read-only bounds
-            let current_input = state.get_current_input();
-            let new_pos = safe_cursor_position(current_input, *ideal_cursor_column, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveDown => {
-            let current_field = state.current_field();
-            let total_fields = state.fields().len();
-            if total_fields == 0 {
-                return Ok(ActionResult::success_with_message("No fields to navigate"));
-            }
-
-            let new_field = (current_field + 1).min(total_fields - 1);
-            state.set_current_field(new_field);
-
-            // Apply ideal cursor column with read-only bounds
-            let current_input = state.get_current_input();
-            let new_pos = safe_cursor_position(current_input, *ideal_cursor_column, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveFirstLine => {
-            let total_fields = state.fields().len();
-            if total_fields == 0 {
-                return Ok(ActionResult::success_with_message("No fields to navigate"));
-            }
-
-            state.set_current_field(0);
-            let current_input = state.get_current_input();
-            let new_pos = safe_cursor_position(current_input, *ideal_cursor_column, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveLastLine => {
-            let total_fields = state.fields().len();
-            if total_fields == 0 {
-                return Ok(ActionResult::success_with_message("No fields to navigate"));
-            }
-
-            let last_field = total_fields - 1;
-            state.set_current_field(last_field);
-            let current_input = state.get_current_input();
-            let new_pos = safe_cursor_position(current_input, *ideal_cursor_column, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveLineStart => {
-            let new_pos = line_start_position();
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveLineEnd => {
-            let current_input = state.get_current_input();
-            let new_pos = line_end_position(current_input, FOR_EDIT_MODE);
-            state.set_current_cursor_pos(new_pos);
-            *ideal_cursor_column = new_pos;
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordNext => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_next_word_start(current_input, state.current_cursor_pos());
-                let final_pos = clamp_cursor_position(new_pos, current_input, FOR_EDIT_MODE);
-                state.set_current_cursor_pos(final_pos);
-                *ideal_cursor_column = final_pos;
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordEnd => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let current_pos = state.current_cursor_pos();
-                let new_pos = find_word_end(current_input, current_pos);
-                let final_pos = clamp_cursor_position(new_pos, current_input, FOR_EDIT_MODE);
-                state.set_current_cursor_pos(final_pos);
-                *ideal_cursor_column = final_pos;
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordPrev => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_prev_word_start(current_input, state.current_cursor_pos());
-                state.set_current_cursor_pos(new_pos);
-                *ideal_cursor_column = new_pos;
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::MoveWordEndPrev => {
-            let current_input = state.get_current_input();
-            if !current_input.is_empty() {
-                let new_pos = find_prev_word_end(current_input, state.current_cursor_pos());
-                state.set_current_cursor_pos(new_pos);
-                *ideal_cursor_column = new_pos;
-            }
-            Ok(ActionResult::success())
-        }
-
-        CanvasAction::NextField | CanvasAction::PrevField => {
-            let current_field = state.current_field();
-            let total_fields = state.fields().len();
-
-            let new_field = match action {
-                CanvasAction::NextField => {
-                    (current_field + 1) % total_fields // Simple wrap
-                }
-                CanvasAction::PrevField => {
-                    if current_field == 0 { total_fields - 1 } else { current_field - 1 } // Simple wrap
-                }
-                _ => unreachable!(),
-            };
-
-            state.set_current_field(new_field);
-            *ideal_cursor_column = state.current_cursor_pos();
-            Ok(ActionResult::success())
-        }
-
-        // Read-only mode doesn't handle editing actions
-        CanvasAction::InsertChar(_) |
-        CanvasAction::DeleteBackward |
-        CanvasAction::DeleteForward => {
-            Ok(ActionResult::success_with_message("Action not available in read-only mode"))
-        }
-
-        CanvasAction::Custom(action_str) => {
-            Ok(ActionResult::success_with_message(&format!("Custom readonly action: {}", action_str)))
-        }
-
-        _ => {
-            Ok(ActionResult::success_with_message("Action not implemented for read-only mode"))
-        }
-    }
-}
--- a/canvas/src/canvas/actions/mod.rs
+++ b/canvas/src/canvas/actions/mod.rs
@@ -1,8 +1,7 @@
 // src/canvas/actions/mod.rs

 pub mod types;
-pub mod handlers;
 pub mod movement;

 // Re-export the main API
-pub use types::{CanvasAction, ActionResult, execute};
+pub use types::{CanvasAction, ActionResult};
--- a/canvas/src/canvas/actions/movement/mod.rs
+++ b/canvas/src/canvas/actions/movement/mod.rs
@@ -5,6 +5,12 @@ pub mod line;
 pub mod char;

 // Re-export commonly used functions
-pub use word::{find_next_word_start, find_word_end, find_prev_word_start, find_prev_word_end};
+pub use word::{
+    find_next_word_start, find_word_end, find_prev_word_start, find_prev_word_end,
+    find_next_big_word_start, find_prev_big_word_start, find_big_word_end, find_prev_big_word_end,
+    // Add these new exports:
+    find_last_word_start_in_field, find_last_word_end_in_field,
+    find_last_big_word_start_in_field, find_last_big_word_end_in_field,
+};
 pub use line::{line_start_position, line_end_position, safe_cursor_position};
 pub use char::{move_left, move_right, is_valid_cursor_position, clamp_cursor_position};
--- a/canvas/src/canvas/actions/movement/word.rs
+++ b/canvas/src/canvas/actions/movement/word.rs
@@ -1,6 +1,7 @@
 // src/canvas/actions/movement/word.rs
+// Replace the entire file with this corrected version:

-#[derive(PartialEq)]
+#[derive(PartialEq, Copy, Clone)]
 enum CharType {
    Whitespace,
    Alphanumeric,
@@ -55,7 +56,7 @@ pub fn find_word_end(text: &str, current_pos: usize) -> usize {

    let mut pos = current_pos.min(len - 1);
    let current_type = get_char_type(chars[pos]);
-    
+
    // If we're not on whitespace, move to end of current word
    if current_type != CharType::Whitespace {
        while pos < len && get_char_type(chars[pos]) == current_type {
@@ -107,40 +108,296 @@ pub fn find_prev_word_start(text: &str, current_pos: usize) -> usize {
    }
 }

-/// Find the end of the previous word
+/// Find the end of the previous word (CORRECTED VERSION for vim's ge command)
 pub fn find_prev_word_end(text: &str, current_pos: usize) -> usize {
    let chars: Vec<char> = text.chars().collect();
    if chars.is_empty() || current_pos == 0 {
        return 0;
    }

+    // Find all word end positions using boundary detection
+    let mut word_ends = Vec::new();
+    let mut in_word = false;
+    let mut current_word_type: Option<CharType> = None;
+
+    for (i, &ch) in chars.iter().enumerate() {
+        let char_type = get_char_type(ch);
+        
+        match char_type {
+            CharType::Whitespace => {
+                if in_word {
+                    // End of a word
+                    word_ends.push(i - 1);
+                    in_word = false;
+                    current_word_type = None;
+                }
+            }
+            _ => {
+                if !in_word || current_word_type != Some(char_type) {
+                    // Start of a new word (or word type change)
+                    if in_word {
+                        // End the previous word first
+                        word_ends.push(i - 1);
+                    }
+                    in_word = true;
+                    current_word_type = Some(char_type);
+                }
+            }
+        }
+    }
+
+    // Add the final word end if text doesn't end with whitespace
+    if in_word && !chars.is_empty() {
+        word_ends.push(chars.len() - 1);
+    }
+
+    // Find the largest word end position that's before current_pos
+    for &end_pos in word_ends.iter().rev() {
+        if end_pos < current_pos {
+            return end_pos;
+        }
+    }
+
+    0
+}
+
+/// Find the start of the next big_word (whitespace-separated)
+pub fn find_next_big_word_start(text: &str, current_pos: usize) -> usize {
+    let chars: Vec<char> = text.chars().collect();
+    if chars.is_empty() || current_pos >= chars.len() {
+        return text.chars().count();
+    }
+
+    let mut pos = current_pos;
+
+    // If we're on non-whitespace, skip to end of current big_word
+    while pos < chars.len() && !chars[pos].is_whitespace() {
+        pos += 1;
+    }
+
+    // Skip whitespace to find start of next big_word
+    while pos < chars.len() && chars[pos].is_whitespace() {
+        pos += 1;
+    }
+
+    pos
+}
+
+/// Find the start of the previous big_word (whitespace-separated)
+pub fn find_prev_big_word_start(text: &str, current_pos: usize) -> usize {
+    let chars: Vec<char> = text.chars().collect();
+    if chars.is_empty() || current_pos == 0 {
+        return 0;
+    }
+
    let mut pos = current_pos.saturating_sub(1);

    // Skip whitespace backwards
-    while pos > 0 && get_char_type(chars[pos]) == CharType::Whitespace {
+    while pos > 0 && chars[pos].is_whitespace() {
        pos -= 1;
    }

-    if pos == 0 && get_char_type(chars[0]) == CharType::Whitespace {
-        return 0;
-    }
-    if pos == 0 && get_char_type(chars[0]) != CharType::Whitespace {
-        return 0;
-    }
-
-    let word_type = get_char_type(chars[pos]);
-    while pos > 0 && get_char_type(chars[pos - 1]) == word_type {
+    // Find start of current big_word by going back while non-whitespace
+    while pos > 0 && !chars[pos - 1].is_whitespace() {
        pos -= 1;
    }

-    // Skip whitespace before this word
-    while pos > 0 && get_char_type(chars[pos - 1]) == CharType::Whitespace {
-        pos -= 1;
-    }
-
-    if pos > 0 {
-        pos - 1
-    } else {
-        0
-    }
+    pos
+}
+
+/// Find the end of the current/next big_word (whitespace-separated)
+pub fn find_big_word_end(text: &str, current_pos: usize) -> usize {
+    let chars: Vec<char> = text.chars().collect();
+    if chars.is_empty() {
+        return 0;
+    }
+
+    let mut pos = current_pos;
+
+    // If we're on whitespace, skip to start of next big_word
+    while pos < chars.len() && chars[pos].is_whitespace() {
+        pos += 1;
+    }
+
+    // If we reached end, return it
+    if pos >= chars.len() {
+        return chars.len();
+    }
+
+    // Find end of current big_word (last non-whitespace char)
+    while pos < chars.len() && !chars[pos].is_whitespace() {
+        pos += 1;
+    }
+
+    // Return position of last character in big_word
+    pos.saturating_sub(1)
+}
+
+/// Find the end of the previous big_word (whitespace-separated)
+pub fn find_prev_big_word_end(text: &str, current_pos: usize) -> usize {
+    let chars: Vec<char> = text.chars().collect();
+    if chars.is_empty() || current_pos == 0 {
+        return 0;
+    }
+
+    let mut pos = current_pos.saturating_sub(1);
+
+    // Skip whitespace backwards
+    while pos > 0 && chars[pos].is_whitespace() {
+        pos -= 1;
+    }
+
+    // If we hit start of text and it's whitespace, return 0
+    if pos == 0 && chars[0].is_whitespace() {
+        return 0;
+    }
+
+    // Skip back to start of current big_word, then forward to end
+    while pos > 0 && !chars[pos - 1].is_whitespace() {
+        pos -= 1;
+    }
+
+    // Now find end of this big_word
+    while pos < chars.len() && !chars[pos].is_whitespace() {
+        pos += 1;
+    }
+
+    // Return position of last character in big_word
+    pos.saturating_sub(1)
+}
+
+// ============================================================================
+// FIELD BOUNDARY HELPER FUNCTIONS (for cross-field movement)
+// ============================================================================
+
+/// Find the start of the last word in a field (for cross-field 'b' movement)
+pub fn find_last_word_start_in_field(text: &str) -> usize {
+    if text.is_empty() {
+        return 0;
+    }
+
+    let chars: Vec<char> = text.chars().collect();
+    if chars.is_empty() {
+        return 0;
+    }
+
+    let mut pos = chars.len().saturating_sub(1);
+
+    // Skip trailing whitespace
+    while pos > 0 && chars[pos].is_whitespace() {
+        pos -= 1;
+    }
+
+    // If the whole field is whitespace, return 0
+    if pos == 0 && chars[0].is_whitespace() {
+        return 0;
+    }
+
+    // Now we're on a non-whitespace character
+    // Find the start of this word by going backwards while chars are the same type
+    let char_type = if chars[pos].is_alphanumeric() { "alnum" } else { "punct" };
+
+    while pos > 0 {
+        let prev_char = chars[pos - 1];
+        let prev_type = if prev_char.is_alphanumeric() {
+            "alnum"
+        } else if prev_char.is_whitespace() {
+            "space"
+        } else {
+            "punct"
+        };
+
+        // Stop if we hit whitespace or different word type
+        if prev_type == "space" || prev_type != char_type {
+            break;
+        }
+        pos -= 1;
+    }
+
+    pos
+}
+
+/// Find the end of the last word in a field (for cross-field 'ge' movement)
+pub fn find_last_word_end_in_field(text: &str) -> usize {
+    let chars: Vec<char> = text.chars().collect();
+    if chars.is_empty() {
+        return 0;
+    }
+
+    // Start from the end and find the last non-whitespace character
+    let mut pos = chars.len() - 1;
+    
+    // Skip trailing whitespace
+    while pos > 0 && chars[pos].is_whitespace() {
+        pos -= 1;
+    }
+
+    // If the whole field is whitespace, return 0
+    if chars[pos].is_whitespace() {
+        return 0;
+    }
+
+    // We're now at the end of the last word
+    pos
+}
+
+/// Find the start of the last big_word in a field (for cross-field 'B' movement)
+pub fn find_last_big_word_start_in_field(text: &str) -> usize {
+    if text.is_empty() {
+        return 0;
+    }
+
+    let chars: Vec<char> = text.chars().collect();
+    if chars.is_empty() {
+        return 0;
+    }
+
+    let mut pos = chars.len().saturating_sub(1);
+
+    // Skip trailing whitespace
+    while pos > 0 && chars[pos].is_whitespace() {
+        pos -= 1;
+    }
+
+    // If the whole field is whitespace, return 0
+    if pos == 0 && chars[0].is_whitespace() {
+        return 0;
+    }
+
+    // Now we're on a non-whitespace character
+    // Find the start of this big_word by going backwards while chars are non-whitespace
+    while pos > 0 {
+        let prev_char = chars[pos - 1];
+
+        // Stop if we hit whitespace (big_word boundary)
+        if prev_char.is_whitespace() {
+            break;
+        }
+        pos -= 1;
+    }
+
+    pos
+}
+
+/// Find the end of the last big_word in a field (for cross-field 'gE' movement)
+pub fn find_last_big_word_end_in_field(text: &str) -> usize {
+    let chars: Vec<char> = text.chars().collect();
+    if chars.is_empty() {
+        return 0;
+    }
+
+    let mut pos = chars.len().saturating_sub(1);
+
+    // Skip trailing whitespace
+    while pos > 0 && chars[pos].is_whitespace() {
+        pos -= 1;
+    }
+
+    // If the whole field is whitespace, return 0
+    if pos == 0 && chars[0].is_whitespace() {
+        return 0;
+    }
+
+    // We're now at the end of the last big_word
+    pos
 }
--- a/canvas/src/canvas/actions/types.rs
+++ b/canvas/src/canvas/actions/types.rs
@@ -1,8 +1,5 @@
 // src/canvas/actions/types.rs

-use crate::canvas::state::CanvasState;
-use anyhow::Result;
-
 /// All available canvas actions
 #[derive(Debug, Clone, PartialEq)]
 pub enum CanvasAction {
@@ -11,35 +8,35 @@ pub enum CanvasAction {
    MoveRight,
    MoveUp,
    MoveDown,
-    
+
    // Word movement
    MoveWordNext,
    MoveWordPrev,
    MoveWordEnd,
    MoveWordEndPrev,
-    
+
    // Line movement
    MoveLineStart,
    MoveLineEnd,
-    
+
    // Field movement
    NextField,
    PrevField,
    MoveFirstLine,
    MoveLastLine,
-    
+
    // Editing actions
    InsertChar(char),
    DeleteBackward,
    DeleteForward,
-    
-    // Autocomplete actions
-    TriggerAutocomplete,
-    SuggestionUp,
-    SuggestionDown,
-    SelectSuggestion,
-    ExitSuggestions,
-    
+
+    // Suggestions actions
+        TriggerSuggestions,
+        SuggestionUp,
+        SuggestionDown,
+        SelectSuggestion,
+        ExitSuggestions,
+
    // Custom actions
    Custom(String),
 }
@@ -58,23 +55,23 @@ impl ActionResult {
    pub fn success() -> Self {
        Self::Success
    }
-    
+
    pub fn success_with_message(msg: &str) -> Self {
        Self::Message(msg.to_string())
    }
-    
+
    pub fn handled_by_app(msg: &str) -> Self {
        Self::HandledByApp(msg.to_string())
    }
-    
+
    pub fn error(msg: &str) -> Self {
        Self::Error(msg.to_string())
    }
-    
+
    pub fn is_success(&self) -> bool {
        matches!(self, Self::Success | Self::Message(_) | Self::HandledByApp(_) | Self::HandledByFeature(_))
    }
-    
+
    pub fn message(&self) -> Option<&str> {
        match self {
            Self::Message(msg) | Self::HandledByApp(msg) | Self::HandledByFeature(msg) | Self::Error(msg) => Some(msg),
@@ -83,16 +80,6 @@ impl ActionResult {
    }
 }

-/// Execute a canvas action on the given state
-pub async fn execute<S: CanvasState>(
-    action: CanvasAction,
-    state: &mut S,
-) -> Result<ActionResult> {
-    let mut ideal_cursor_column = 0;
-    
-    super::handlers::dispatch_action(action, state, &mut ideal_cursor_column).await
-}
-
 impl CanvasAction {
    /// Get a human-readable description of this action
    pub fn description(&self) -> &'static str {
@@ -111,15 +98,15 @@ impl CanvasAction {
            Self::PrevField => "previous field",
            Self::MoveFirstLine => "first field",
            Self::MoveLastLine => "last field",
-            Self::InsertChar(c) => "insert character",
+            Self::InsertChar(_c) => "insert character",
            Self::DeleteBackward => "delete backward",
            Self::DeleteForward => "delete forward",
-            Self::TriggerAutocomplete => "trigger autocomplete",
+            Self::TriggerSuggestions => "trigger suggestions",
            Self::SuggestionUp => "suggestion up",
            Self::SuggestionDown => "suggestion down",
            Self::SelectSuggestion => "select suggestion",
            Self::ExitSuggestions => "exit suggestions",
-            Self::Custom(name) => "custom action",
+            Self::Custom(_name) => "custom action",
        }
    }

@@ -152,10 +139,10 @@ impl CanvasAction {
        ]
    }

-    /// Get all autocomplete-related actions
-    pub fn autocomplete_actions() -> Vec<CanvasAction> {
+    /// Get all suggestions-related actions
+    pub fn suggestions_actions() -> Vec<CanvasAction> {
        vec![
-            Self::TriggerAutocomplete,
+            Self::TriggerSuggestions,
            Self::SuggestionUp,
            Self::SuggestionDown,
            Self::SelectSuggestion,
--- a/canvas/src/canvas/cursor.rs
+++ b/canvas/src/canvas/cursor.rs
@@ -0,0 +1,45 @@
+// src/canvas/cursor.rs
+//! Cursor style management for different canvas modes
+
+#[cfg(feature = "cursor-style")]
+use crossterm::{cursor::SetCursorStyle, execute};
+#[cfg(feature = "cursor-style")]
+use std::io;
+
+use crate::canvas::modes::AppMode;
+
+/// Manages cursor styles based on canvas modes
+pub struct CursorManager;
+
+impl CursorManager {
+    /// Update cursor style based on current mode
+    #[cfg(feature = "cursor-style")]
+    pub fn update_for_mode(mode: AppMode) -> io::Result<()> {
+        let style = match mode {
+            AppMode::Edit => SetCursorStyle::SteadyBar,           // Thin line for insert
+            AppMode::ReadOnly => SetCursorStyle::SteadyBlock,     // Block for normal
+            AppMode::Highlight => SetCursorStyle::BlinkingBlock,  // Blinking for visual
+            AppMode::General => SetCursorStyle::SteadyBlock,      // Block for general
+            AppMode::Command => SetCursorStyle::SteadyUnderScore, // Underscore for command
+        };
+        
+        execute!(io::stdout(), style)
+    }
+
+    /// No-op when cursor-style feature is disabled
+    #[cfg(not(feature = "cursor-style"))]
+    pub fn update_for_mode(_mode: AppMode) -> io::Result<()> {
+        Ok(())
+    }
+
+    /// Reset cursor to default on cleanup
+    #[cfg(feature = "cursor-style")]
+    pub fn reset() -> io::Result<()> {
+        execute!(io::stdout(), SetCursorStyle::DefaultUserShape)
+    }
+
+    #[cfg(not(feature = "cursor-style"))]
+    pub fn reset() -> io::Result<()> {
+        Ok(())
+    }
+}
--- a/canvas/src/canvas/gui.rs
+++ b/canvas/src/canvas/gui.rs
@@ -1,4 +1,5 @@
-// canvas/src/canvas/gui.rs
+// src/canvas/gui.rs
+//! Canvas GUI updated to work with FormEditor

 #[cfg(feature = "gui")]
 use ratatui::{
@@ -9,28 +10,76 @@ use ratatui::{
    Frame,
 };

-use crate::canvas::state::CanvasState;
-use crate::canvas::modes::HighlightState;
-
 #[cfg(feature = "gui")]
-use crate::canvas::theme::CanvasTheme;
+use crate::canvas::theme::{CanvasTheme, DefaultCanvasTheme};
+use crate::canvas::modes::HighlightState;
+use crate::data_provider::DataProvider;
+use crate::editor::FormEditor;
+use unicode_width::UnicodeWidthChar;

 #[cfg(feature = "gui")]
 use std::cmp::{max, min};

-/// Render ONLY the canvas form fields - no autocomplete
+/// Render ONLY the canvas form fields - no suggestions rendering here
+/// Updated to work with FormEditor instead of CanvasState trait
 #[cfg(feature = "gui")]
-pub fn render_canvas<T: CanvasTheme>(
+pub fn render_canvas<T: CanvasTheme, D: DataProvider>(
    f: &mut Frame,
    area: Rect,
-    form_state: &impl CanvasState,
+    editor: &FormEditor<D>,
+    theme: &T,
+) -> Option<Rect> {
+    // Convert SelectionState to HighlightState
+    let highlight_state = convert_selection_to_highlight(editor.ui_state().selection_state());
+    render_canvas_with_highlight(f, area, editor, theme, &highlight_state)
+}
+
+/// Render canvas with explicit highlight state (for advanced use)
+#[cfg(feature = "gui")]
+pub fn render_canvas_with_highlight<T: CanvasTheme, D: DataProvider>(
+    f: &mut Frame,
+    area: Rect,
+    editor: &FormEditor<D>,
    theme: &T,
-    is_edit_mode: bool,
    highlight_state: &HighlightState,
 ) -> Option<Rect> {
-    let fields: Vec<&str> = form_state.fields();
-    let current_field_idx = form_state.current_field();
-    let inputs: Vec<&String> = form_state.inputs();
+    let ui_state = editor.ui_state();
+    let data_provider = editor.data_provider();
+
+    // Build field information
+    let field_count = data_provider.field_count();
+    let mut fields: Vec<&str> = Vec::with_capacity(field_count);
+    let mut inputs: Vec<String> = Vec::with_capacity(field_count);
+
+    for i in 0..field_count {
+        fields.push(data_provider.field_name(i));
+
+        // Use editor-provided effective display text per field (Feature 4/mask aware)
+        #[cfg(feature = "validation")]
+        {
+            inputs.push(editor.display_text_for_field(i));
+        }
+        #[cfg(not(feature = "validation"))]
+        {
+            inputs.push(data_provider.field_value(i).to_string());
+        }
+    }
+
+    let current_field_idx = ui_state.current_field();
+    let is_edit_mode = matches!(ui_state.mode(), crate::canvas::modes::AppMode::Edit);
+
+    // Precompute completion for active field
+    #[cfg(feature = "suggestions")]
+    let active_completion = if ui_state.is_suggestions_active()
+        && ui_state.suggestions.active_field == Some(current_field_idx)
+    {
+        ui_state.suggestions.completion_text.clone()
+    } else {
+        None
+    };
+
+    #[cfg(not(feature = "suggestions"))]
+    let active_completion: Option<String> = None;

    render_canvas_fields(
        f,
@@ -41,21 +90,57 @@ pub fn render_canvas<T: CanvasTheme>(
        theme,
        is_edit_mode,
        highlight_state,
-        form_state.current_cursor_pos(),
-        form_state.has_unsaved_changes(),
-        |i| form_state.get_display_value_for_field(i).to_string(),
-        |i| form_state.has_display_override(i),
+        editor.display_cursor_position(), // Use display cursor position for masks
+        false, // TODO: track unsaved changes in editor
+        // Closures for getting display values and overrides
+        #[cfg(feature = "validation")]
+        |field_idx| editor.display_text_for_field(field_idx),
+        #[cfg(not(feature = "validation"))]
+        |field_idx| data_provider.field_value(field_idx).to_string(),
+        // Closure for checking display overrides
+        #[cfg(feature = "validation")]
+        |field_idx| {
+            editor.ui_state().validation_state().get_field_config(field_idx)
+                .map(|cfg| {
+                    let has_formatter = cfg.custom_formatter.is_some();
+                    let has_mask = cfg.display_mask.is_some();
+                    has_formatter || has_mask
+                })
+                .unwrap_or(false)
+        },
+        #[cfg(not(feature = "validation"))]
+        |_field_idx| false,
+        // Closure for providing completion
+        |field_idx| {
+            if field_idx == current_field_idx {
+                active_completion.clone()
+            } else {
+                None
+            }
+        },
    )
 }

+/// Convert SelectionState to HighlightState for rendering
+#[cfg(feature = "gui")]
+fn convert_selection_to_highlight(selection: &crate::canvas::state::SelectionState) -> HighlightState {
+    use crate::canvas::state::SelectionState;
+
+    match selection {
+        SelectionState::None => HighlightState::Off,
+        SelectionState::Characterwise { anchor } => HighlightState::Characterwise { anchor: *anchor },
+        SelectionState::Linewise { anchor_field } => HighlightState::Linewise { anchor_line: *anchor_field },
+    }
+}
+
 /// Core canvas field rendering
 #[cfg(feature = "gui")]
-fn render_canvas_fields<T: CanvasTheme, F1, F2>(
+fn render_canvas_fields<T: CanvasTheme, F1, F2, F3>(
    f: &mut Frame,
    area: Rect,
    fields: &[&str],
    current_field_idx: &usize,
-    inputs: &[&String],
+    inputs: &[String],
    theme: &T,
    is_edit_mode: bool,
    highlight_state: &HighlightState,
@@ -63,10 +148,12 @@ fn render_canvas_fields<T: CanvasTheme, F1, F2>(
    has_unsaved_changes: bool,
    get_display_value: F1,
    has_display_override: F2,
+    get_completion: F3,
 ) -> Option<Rect>
 where
    F1: Fn(usize) -> String,
    F2: Fn(usize) -> bool,
+    F3: Fn(usize) -> Option<String>,
 {
    // Create layout
    let columns = Layout::default()
@@ -112,7 +199,7 @@ where
    // Render field values and return active field rect
    render_field_values(
        f,
-        input_rows.to_vec(), // Fix: Convert Rc<[Rect]> to Vec<Rect>
+        input_rows.to_vec(),
        inputs,
        current_field_idx,
        theme,
@@ -120,6 +207,7 @@ where
        current_cursor_pos,
        get_display_value,
        has_display_override,
+        get_completion,
    )
 }

@@ -151,45 +239,65 @@ fn render_field_labels<T: CanvasTheme>(

 /// Render field values with highlighting
 #[cfg(feature = "gui")]
-fn render_field_values<T: CanvasTheme, F1, F2>(
+fn render_field_values<T: CanvasTheme, F1, F2, F3>(
    f: &mut Frame,
    input_rows: Vec<Rect>,
-    inputs: &[&String],
+    inputs: &[String],
    current_field_idx: &usize,
    theme: &T,
    highlight_state: &HighlightState,
    current_cursor_pos: usize,
    get_display_value: F1,
    has_display_override: F2,
+    get_completion: F3,
 ) -> Option<Rect>
 where
    F1: Fn(usize) -> String,
    F2: Fn(usize) -> bool,
+    F3: Fn(usize) -> Option<String>,
 {
    let mut active_field_input_rect = None;

-    for (i, _input) in inputs.iter().enumerate() {
+    // FIX: Iterate over indices only since we never use the input values directly
+    for i in 0..inputs.len() {
        let is_active = i == *current_field_idx;
-        let text = get_display_value(i);
-        
-        // Apply highlighting
-        let line = apply_highlighting(
-            &text,
-            i,
-            current_field_idx,
-            current_cursor_pos,
-            highlight_state,
-            theme,
-            is_active,
-        );
+        let typed_text = get_display_value(i);
+
+        let line = if is_active {
+            // Compose typed + gray completion for the active field
+            let normal_style = Style::default().fg(theme.fg());
+            let gray_style = Style::default().fg(theme.suggestion_gray());
+
+            let mut spans: Vec<Span> = Vec::new();
+            spans.push(Span::styled(typed_text.clone(), normal_style));
+
+            if let Some(completion) = get_completion(i) {
+                if !completion.is_empty() {
+                    spans.push(Span::styled(completion, gray_style));
+                }
+            }
+
+            Line::from(spans)
+        } else {
+            // Non-active fields: keep existing highlighting logic
+            apply_highlighting(
+                &typed_text,
+                i,
+                current_field_idx,
+                current_cursor_pos,
+                highlight_state,
+                theme,
+                is_active,
+            )
+        };

        let input_display = Paragraph::new(line).alignment(Alignment::Left);
        f.render_widget(input_display, input_rows[i]);

-        // Set cursor for active field
+        // Set cursor for active field at end of typed text (not after completion)
        if is_active {
            active_field_input_rect = Some(input_rows[i]);
-            set_cursor_position(f, input_rows[i], &text, current_cursor_pos, has_display_override(i));
+            set_cursor_position(f, input_rows[i], &typed_text, current_cursor_pos, has_display_override(i));
        }
    }

@@ -213,11 +321,7 @@ fn apply_highlighting<'a, T: CanvasTheme>(
        HighlightState::Off => {
            Line::from(Span::styled(
                text,
-                if is_active {
-                    Style::default().fg(theme.highlight())
-                } else {
-                    Style::default().fg(theme.fg())
-                },
+                Style::default().fg(theme.fg())
            ))
        }
        HighlightState::Characterwise { anchor } => {
@@ -229,7 +333,7 @@ fn apply_highlighting<'a, T: CanvasTheme>(
    }
 }

-/// Apply characterwise highlighting
+/// Apply characterwise highlighting - PROPER VIM-LIKE VERSION
 #[cfg(feature = "gui")]
 fn apply_characterwise_highlighting<'a, T: CanvasTheme>(
    text: &'a str,
@@ -239,21 +343,25 @@ fn apply_characterwise_highlighting<'a, T: CanvasTheme>(
    current_cursor_pos: usize,
    anchor: &(usize, usize),
    theme: &T,
-    is_active: bool,
+    _is_active: bool,
 ) -> Line<'a> {
    let (anchor_field, anchor_char) = *anchor;
    let start_field = min(anchor_field, *current_field_idx);
    let end_field = max(anchor_field, *current_field_idx);

+    // Vim-like styling:
+    // - Selected text: contrasting color + background (like vim visual selection)
+    // - All other text: normal color (no special colors for active fields, etc.)
    let highlight_style = Style::default()
-        .fg(theme.highlight())
-        .bg(theme.highlight_bg())
+        .fg(theme.highlight())          // ✅ Contrasting text color for selected text
+        .bg(theme.highlight_bg())       // ✅ Background for selected text
        .add_modifier(Modifier::BOLD);
-    let normal_style_in_highlight = Style::default().fg(theme.highlight());
-    let normal_style_outside = Style::default().fg(theme.fg());
+
+    let normal_style = Style::default().fg(theme.fg()); // ✅ Normal text color everywhere else

    if field_index >= start_field && field_index <= end_field {
        if start_field == end_field {
+            // Single field selection
            let (start_char, end_char) = if anchor_field == *current_field_idx {
                (min(anchor_char, current_cursor_pos), max(anchor_char, current_cursor_pos))
            } else if anchor_field < *current_field_idx {
@@ -273,23 +381,64 @@ fn apply_characterwise_highlighting<'a, T: CanvasTheme>(
            let after: String = text.chars().skip(clamped_end + 1).collect();

            Line::from(vec![
-                Span::styled(before, normal_style_in_highlight),
-                Span::styled(highlighted, highlight_style),
-                Span::styled(after, normal_style_in_highlight),
+                Span::styled(before, normal_style),         // Normal text color
+                Span::styled(highlighted, highlight_style), // Contrasting color + background
+                Span::styled(after, normal_style),          // Normal text color
            ])
        } else {
            // Multi-field selection
-            Line::from(Span::styled(text, highlight_style))
+            if field_index == anchor_field {
+                if anchor_field < *current_field_idx {
+                    let clamped_start = anchor_char.min(text_len);
+                    let before: String = text.chars().take(clamped_start).collect();
+                    let highlighted: String = text.chars().skip(clamped_start).collect();
+
+                    Line::from(vec![
+                        Span::styled(before, normal_style),
+                        Span::styled(highlighted, highlight_style),
+                    ])
+                } else {
+                    let clamped_end = anchor_char.min(text_len);
+                    let highlighted: String = text.chars().take(clamped_end + 1).collect();
+                    let after: String = text.chars().skip(clamped_end + 1).collect();
+
+                    Line::from(vec![
+                        Span::styled(highlighted, highlight_style),
+                        Span::styled(after, normal_style),
+                    ])
+                }
+            } else if field_index == *current_field_idx {
+                if anchor_field < *current_field_idx {
+                    let clamped_end = current_cursor_pos.min(text_len);
+                    let highlighted: String = text.chars().take(clamped_end + 1).collect();
+                    let after: String = text.chars().skip(clamped_end + 1).collect();
+
+                    Line::from(vec![
+                        Span::styled(highlighted, highlight_style),
+                        Span::styled(after, normal_style),
+                    ])
+                } else {
+                    let clamped_start = current_cursor_pos.min(text_len);
+                    let before: String = text.chars().take(clamped_start).collect();
+                    let highlighted: String = text.chars().skip(clamped_start).collect();
+
+                    Line::from(vec![
+                        Span::styled(before, normal_style),
+                        Span::styled(highlighted, highlight_style),
+                    ])
+                }
+            } else {
+                // Middle field: highlight entire field
+                Line::from(Span::styled(text, highlight_style))
+            }
        }
    } else {
-        Line::from(Span::styled(
-            text,
-            if is_active { normal_style_in_highlight } else { normal_style_outside }
-        ))
+        // Outside selection: always normal text color (no special active field color)
+        Line::from(Span::styled(text, normal_style))
    }
 }

-/// Apply linewise highlighting
+/// Apply linewise highlighting - PROPER VIM-LIKE VERSION
 #[cfg(feature = "gui")]
 fn apply_linewise_highlighting<'a, T: CanvasTheme>(
    text: &'a str,
@@ -297,25 +446,27 @@ fn apply_linewise_highlighting<'a, T: CanvasTheme>(
    current_field_idx: &usize,
    anchor_line: &usize,
    theme: &T,
-    is_active: bool,
+    _is_active: bool,
 ) -> Line<'a> {
    let start_field = min(*anchor_line, *current_field_idx);
    let end_field = max(*anchor_line, *current_field_idx);
-    
+
+    // Vim-like styling:
+    // - Selected lines: contrasting text color + background
+    // - All other lines: normal text color (no special active field color)
    let highlight_style = Style::default()
-        .fg(theme.highlight())
-        .bg(theme.highlight_bg())
+        .fg(theme.highlight())          // ✅ Contrasting text color for selected text
+        .bg(theme.highlight_bg())       // ✅ Background for selected text
        .add_modifier(Modifier::BOLD);
-    let normal_style_in_highlight = Style::default().fg(theme.highlight());
-    let normal_style_outside = Style::default().fg(theme.fg());
+
+    let normal_style = Style::default().fg(theme.fg()); // ✅ Normal text color everywhere else

    if field_index >= start_field && field_index <= end_field {
+        // Selected line: contrasting text color + background
        Line::from(Span::styled(text, highlight_style))
    } else {
-        Line::from(Span::styled(
-            text,
-            if is_active { normal_style_in_highlight } else { normal_style_outside }
-        ))
+        // Normal line: normal text color (no special active field color)
+        Line::from(Span::styled(text, normal_style))
    }
 }

@@ -326,13 +477,34 @@ fn set_cursor_position(
    field_rect: Rect,
    text: &str,
    current_cursor_pos: usize,
-    has_display_override: bool,
+    _has_display_override: bool,
 ) {
-    let cursor_x = if has_display_override {
-        field_rect.x + text.chars().count() as u16
-    } else {
-        field_rect.x + current_cursor_pos as u16
-    };
+    // Sum display widths of the first current_cursor_pos characters
+    let mut cols: u16 = 0;
+    for (i, ch) in text.chars().enumerate() {
+        if i >= current_cursor_pos {
+            break;
+        }
+        cols = cols.saturating_add(UnicodeWidthChar::width(ch).unwrap_or(0) as u16);
+    }
+
+    let cursor_x = field_rect.x.saturating_add(cols);
    let cursor_y = field_rect.y;
-    f.set_cursor_position((cursor_x, cursor_y));
+
+    // Clamp to field bounds
+    let max_cursor_x = field_rect.x + field_rect.width.saturating_sub(1);
+    let safe_cursor_x = cursor_x.min(max_cursor_x);
+
+    f.set_cursor_position((safe_cursor_x, cursor_y));
+}
+
+/// Set default theme if custom not specified
+#[cfg(feature = "gui")]
+pub fn render_canvas_default<D: DataProvider>(
+    f: &mut Frame,
+    area: Rect,
+    editor: &FormEditor<D>,
+) -> Option<Rect> {
+    let theme = DefaultCanvasTheme::default();
+    render_canvas(f, area, editor, &theme)
 }
--- a/canvas/src/canvas/mod.rs
+++ b/canvas/src/canvas/mod.rs
@@ -1,18 +1,19 @@
 // src/canvas/mod.rs

 pub mod actions;
-pub mod gui;
-pub mod modes;
 pub mod state;
+pub mod modes;
+
+#[cfg(feature = "gui")]
+pub mod gui;
+#[cfg(feature = "gui")]
 pub mod theme;

-// Re-export main types for convenience
-pub use actions::{CanvasAction, ActionResult};
+#[cfg(feature = "cursor-style")]
+pub mod cursor;
+
+// Keep these exports for current functionality
 pub use modes::{AppMode, ModeManager, HighlightState};
-pub use state::{CanvasState, ActionContext};

-#[cfg(feature = "gui")]
-pub use theme::CanvasTheme;
-
-#[cfg(feature = "gui")]
-pub use gui::render_canvas;
+#[cfg(feature = "cursor-style")]
+pub use cursor::CursorManager;
--- a/canvas/src/canvas/modes/manager.rs
+++ b/canvas/src/canvas/modes/manager.rs
@@ -1,6 +1,8 @@
 // src/modes/handlers/mode_manager.rs
 // canvas/src/modes/manager.rs

+#[cfg(feature = "cursor-style")]
+use crate::canvas::CursorManager;

 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum AppMode {
@@ -30,4 +32,39 @@ impl ModeManager {
    pub fn can_enter_highlight_mode(current_mode: AppMode) -> bool {
        matches!(current_mode, AppMode::ReadOnly)
    }
+
+
+    /// Transition to new mode with automatic cursor update (when cursor-style feature enabled)
+    pub fn transition_to_mode(current_mode: AppMode, new_mode: AppMode) -> std::io::Result<AppMode> {
+        if current_mode != new_mode {
+            #[cfg(feature = "cursor-style")]
+            {
+                let _ = CursorManager::update_for_mode(new_mode);
+            }
+        }
+        Ok(new_mode)
+    }
+
+    /// Enter highlight mode with cursor styling
+    pub fn enter_highlight_mode_with_cursor(current_mode: AppMode) -> std::io::Result<bool> {
+        if Self::can_enter_highlight_mode(current_mode) {
+            #[cfg(feature = "cursor-style")]
+            {
+                let _ = CursorManager::update_for_mode(AppMode::Highlight);
+            }
+            Ok(true)
+        } else {
+            Ok(false)
+        }
+    }
+
+    /// Exit highlight mode with cursor styling
+    pub fn exit_highlight_mode_with_cursor() -> std::io::Result<AppMode> {
+        let new_mode = AppMode::ReadOnly;
+        #[cfg(feature = "cursor-style")]
+        {
+            let _ = CursorManager::update_for_mode(new_mode);
+        }
+        Ok(new_mode)
+    }
 }
--- a/canvas/src/canvas/state.rs
+++ b/canvas/src/canvas/state.rs
@@ -1,117 +1,187 @@
 // src/canvas/state.rs
-//! Canvas state trait and related types
-//! 
-//! This module defines the core trait that any form or input system must implement
-//! to work with the canvas library.
+//! Library-owned UI state - user never directly modifies this

-use crate::canvas::actions::CanvasAction;
 use crate::canvas::modes::AppMode;

-/// Context information passed to feature-specific action handlers
-#[derive(Debug)]
-pub struct ActionContext {
-    /// Original key code that triggered this action (for backwards compatibility)
-    pub key_code: Option<crossterm::event::KeyCode>,
-    /// Current ideal cursor column for vertical movement
-    pub ideal_cursor_column: usize,
-    /// Current input text
-    pub current_input: String,
-    /// Current field index
-    pub current_field: usize,
+/// Library-owned UI state - user never directly modifies this
+#[derive(Debug, Clone)]
+pub struct EditorState {
+    // Navigation state
+    pub(crate) current_field: usize,
+    pub(crate) cursor_pos: usize,
+    pub(crate) ideal_cursor_column: usize,
+
+    // Mode state
+    pub(crate) current_mode: AppMode,
+
+    // Suggestions dropdown state (only available with suggestions feature)
+    #[cfg(feature = "suggestions")]
+    pub(crate) suggestions: SuggestionsUIState,
+
+    // Selection state (for vim visual mode)
+    pub(crate) selection: SelectionState,
+
+    // Validation state (only available with validation feature)
+    #[cfg(feature = "validation")]
+    pub(crate) validation: crate::validation::ValidationState,
+
+    /// Computed fields state (only when computed feature is enabled)
+    #[cfg(feature = "computed")]
+    pub(crate) computed: Option<crate::computed::ComputedState>,
 }

-/// Core trait that any form-like state must implement to work with canvas
-/// 
-/// This trait enables the same mode behaviors (edit, read-only, highlight) to work
-/// across any implementation - login forms, data entry forms, configuration screens, etc.
-/// 
-/// # Required Implementation
-/// 
-/// Your struct needs to track:
-/// - Current field index and cursor position
-/// - All input field values 
-/// - Current interaction mode
-/// - Whether there are unsaved changes
-/// 
-/// # Example Implementation
-/// 
-/// ```rust
-/// struct MyForm {
-///     fields: Vec<String>,
-///     current_field: usize, 
-///     cursor_pos: usize,
-///     mode: AppMode,
-///     dirty: bool,
-/// }
-/// 
-/// impl CanvasState for MyForm {
-///     fn current_field(&self) -> usize { self.current_field }
-///     fn current_cursor_pos(&self) -> usize { self.cursor_pos }
-///     // ... implement other required methods
-/// }
-/// ```
-pub trait CanvasState {
-    // --- Core Navigation ---
-    
-    /// Get current field index (0-based)
-    fn current_field(&self) -> usize;
-    
-    /// Get current cursor position within the current field
-    fn current_cursor_pos(&self) -> usize;
-    
-    /// Set current field index (should clamp to valid range)
-    fn set_current_field(&mut self, index: usize);
-    
-    /// Set cursor position within current field (should clamp to valid range)
-    fn set_current_cursor_pos(&mut self, pos: usize);
+#[cfg(feature = "suggestions")]
+#[derive(Debug, Clone)]
+pub struct SuggestionsUIState {
+    pub(crate) is_active: bool,
+    pub(crate) is_loading: bool,
+    pub(crate) selected_index: Option<usize>,
+    pub(crate) active_field: Option<usize>,
+    pub(crate) active_query: Option<String>,
+    pub(crate) completion_text: Option<String>,
+}

-    // --- Mode Information ---
-    
-    /// Get current interaction mode (edit, read-only, highlight, etc.)
-    fn current_mode(&self) -> AppMode;
+#[derive(Debug, Clone)]
+pub enum SelectionState {
+    None,
+    Characterwise { anchor: (usize, usize) },
+    Linewise { anchor_field: usize },
+}

-    // --- Data Access ---
-    
-    /// Get immutable reference to current field's text
-    fn get_current_input(&self) -> &str;
-    
-    /// Get mutable reference to current field's text
-    fn get_current_input_mut(&mut self) -> &mut String;
-    
-    /// Get all input values as immutable references
-    fn inputs(&self) -> Vec<&String>;
-    
-    /// Get all field names/labels
-    fn fields(&self) -> Vec<&str>;
-
-    // --- State Management ---
-    
-    /// Check if there are unsaved changes
-    fn has_unsaved_changes(&self) -> bool;
-    
-    /// Mark whether there are unsaved changes
-    fn set_has_unsaved_changes(&mut self, changed: bool);
-
-    // --- Optional Overrides ---
-
-    /// Handle application-specific actions not covered by standard handlers
-    /// Return Some(message) if the action was handled, None to use standard handling
-    fn handle_feature_action(&mut self, _action: &CanvasAction, _context: &ActionContext) -> Option<String> {
-        None // Default: no custom handling
+impl EditorState {
+    pub fn new() -> Self {
+        Self {
+            current_field: 0,
+            cursor_pos: 0,
+            ideal_cursor_column: 0,
+            current_mode: AppMode::Edit,
+            #[cfg(feature = "suggestions")]
+            suggestions: SuggestionsUIState {
+                is_active: false,
+                is_loading: false,
+                selected_index: None,
+                active_field: None,
+                active_query: None,
+                completion_text: None,
+            },
+            selection: SelectionState::None,
+            #[cfg(feature = "validation")]
+            validation: crate::validation::ValidationState::new(),
+            #[cfg(feature = "computed")]
+            computed: None,
+        }
    }

-    /// Get display value for a field (may differ from actual value)
-    /// Used for things like password masking or computed display values
-    fn get_display_value_for_field(&self, index: usize) -> &str {
-        self.inputs()
-            .get(index)
-            .map(|s| s.as_str())
-            .unwrap_or("")
+    // ===================================================================
+    // READ-ONLY ACCESS: User can fetch UI state for compatibility
+    // ===================================================================
+
+    /// Get current field index (for user's business logic)
+    pub fn current_field(&self) -> usize {
+        self.current_field
    }

-    /// Check if a field has a custom display value
-    /// Return true if get_display_value_for_field returns something different than the actual value
-    fn has_display_override(&self, _index: usize) -> bool {
-        false
+    /// Check if field is computed
+    #[cfg(feature = "computed")]
+    pub fn is_computed_field(&self, field_index: usize) -> bool {
+        self.computed
+            .as_ref()
+            .map(|state| state.is_computed_field(field_index))
+            .unwrap_or(false)
+    }
+
+    /// Get current cursor position (for user's business logic)
+    pub fn cursor_position(&self) -> usize {
+        self.cursor_pos
+    }
+
+    /// Get ideal cursor column (for vim-like behavior)
+    pub fn ideal_cursor_column(&self) -> usize {
+        self.ideal_cursor_column
+    }
+
+    /// Get current mode (for user's business logic)
+    pub fn mode(&self) -> AppMode {
+        self.current_mode
+    }
+
+    /// Check if suggestions dropdown is active (for user's business logic)
+    #[cfg(feature = "suggestions")]
+    pub fn is_suggestions_active(&self) -> bool {
+        self.suggestions.is_active
+    }
+
+    /// Check if suggestions dropdown is loading (for user's business logic)
+    #[cfg(feature = "suggestions")]
+    pub fn is_suggestions_loading(&self) -> bool {
+        self.suggestions.is_loading
+    }
+
+    /// Get selection state (for user's business logic)
+    pub fn selection_state(&self) -> &SelectionState {
+        &self.selection
+    }
+
+    /// Get validation state (for user's business logic)
+    /// Only available when the 'validation' feature is enabled
+    #[cfg(feature = "validation")]
+    pub fn validation_state(&self) -> &crate::validation::ValidationState {
+        &self.validation
+    }
+
+    // ===================================================================
+    // INTERNAL MUTATIONS: Only library modifies these
+    // ===================================================================
+
+    pub(crate) fn move_to_field(&mut self, field_index: usize, field_count: usize) {
+        if field_index < field_count {
+            self.current_field = field_index;
+            // Reset cursor to safe position - will be clamped by movement logic
+            self.cursor_pos = 0;
+        }
+    }
+
+    pub(crate) fn set_cursor(
+        &mut self,
+        position: usize,
+        max_position: usize,
+        for_edit_mode: bool,
+    ) {
+        if for_edit_mode {
+            // Edit mode: can go past end for insertion
+            self.cursor_pos = position.min(max_position);
+        } else {
+            // ReadOnly/Highlight: stay within text bounds
+            self.cursor_pos = position.min(max_position.saturating_sub(1));
+        }
+        self.ideal_cursor_column = self.cursor_pos;
+    }
+
+    /// Explicitly open suggestions — should only be called on Tab
+    #[cfg(feature = "suggestions")]
+    pub(crate) fn open_suggestions(&mut self, field_index: usize) {
+        self.suggestions.is_active = true;
+        self.suggestions.is_loading = true;
+        self.suggestions.active_field = Some(field_index);
+        self.suggestions.active_query = None;
+        self.suggestions.selected_index = None;
+        self.suggestions.completion_text = None;
+    }
+
+    /// Explicitly close suggestions — should be called on Esc or field change
+    #[cfg(feature = "suggestions")]
+    pub(crate) fn close_suggestions(&mut self) {
+        self.suggestions.is_active = false;
+        self.suggestions.is_loading = false;
+        self.suggestions.active_field = None;
+        self.suggestions.active_query = None;
+        self.suggestions.selected_index = None;
+        self.suggestions.completion_text = None;
+    }
+}
+
+impl Default for EditorState {
+    fn default() -> Self {
+        Self::new()
    }
 }
--- a/canvas/src/canvas/theme.rs
+++ b/canvas/src/canvas/theme.rs
@@ -14,4 +14,41 @@ pub trait CanvasTheme {
    fn highlight(&self) -> Color;
    fn highlight_bg(&self) -> Color;
    fn warning(&self) -> Color;
+    fn suggestion_gray(&self) -> Color;
+}
+
+
+#[cfg(feature = "gui")]
+#[derive(Debug, Clone, Default)]
+pub struct DefaultCanvasTheme;
+
+#[cfg(feature = "gui")]
+impl CanvasTheme for DefaultCanvasTheme {
+    fn bg(&self) -> Color {
+        Color::Black
+    }
+    fn fg(&self) -> Color {
+        Color::White
+    }
+    fn border(&self) -> Color {
+        Color::DarkGray
+    }
+    fn accent(&self) -> Color {
+        Color::Cyan
+    }
+    fn secondary(&self) -> Color {
+        Color::Gray
+    }
+    fn highlight(&self) -> Color {
+        Color::Yellow
+    }
+    fn highlight_bg(&self) -> Color {
+        Color::Blue
+    }
+    fn warning(&self) -> Color {
+        Color::Red
+    }
+    fn suggestion_gray(&self) -> Color {
+        Color::DarkGray
+    }
 }
--- a/canvas/src/computed/mod.rs
+++ b/canvas/src/computed/mod.rs
@@ -0,0 +1,5 @@
+pub mod provider;
+pub mod state;
+
+pub use provider::{ComputedContext, ComputedProvider};
+pub use state::ComputedState;
--- a/canvas/src/computed/provider.rs
+++ b/canvas/src/computed/provider.rs
@@ -0,0 +1,31 @@
+// ================================================================================================
+// COMPUTED FIELDS - Provider and Context
+// ================================================================================================
+
+/// Context information provided to computed field calculations
+#[derive(Debug, Clone)]
+pub struct ComputedContext<'a> {
+    /// All field values in the form (index -> value)
+    pub field_values: &'a [&'a str],
+    /// The field index being computed
+    pub target_field: usize,
+    /// Current field that user is editing (if any)
+    pub current_field: Option<usize>,
+}
+
+/// User implements this to provide computed field logic
+pub trait ComputedProvider {
+    /// Compute value for a field based on other field values.
+    /// Called automatically when any field changes.
+    fn compute_field(&mut self, context: ComputedContext) -> String;
+
+    /// Check if this provider handles the given field.
+    fn handles_field(&self, field_index: usize) -> bool;
+
+    /// Get list of field dependencies for optimization.
+    /// If field A depends on fields [1, 3], only recompute A when fields 1 or 3 change.
+    /// Default: depend on all fields (always recompute) with a reasonable upper bound.
+    fn field_dependencies(&self, _field_index: usize) -> Vec<usize> {
+        (0..100).collect()
+    }
+}
--- a/canvas/src/computed/state.rs
+++ b/canvas/src/computed/state.rs
@@ -0,0 +1,88 @@
+/* file: canvas/src/computed/state.rs */
+/*
+Add computed state module file implementing caching and dependencies
+*/
+
+// ================================================================================================
+// COMPUTED FIELDS - State: caching and dependencies
+// ================================================================================================
+
+use std::collections::{HashMap, HashSet};
+
+/// Internal state for computed field management
+#[derive(Debug, Clone)]
+pub struct ComputedState {
+    /// Cached computed values (field_index -> computed_value)
+    computed_values: HashMap<usize, String>,
+    /// Field dependency graph (field_index -> depends_on_fields)
+    dependencies: HashMap<usize, Vec<usize>>,
+    /// Track which fields are computed (display-only)
+    computed_fields: HashSet<usize>,
+}
+
+impl ComputedState {
+    /// Create a new, empty computed state
+    pub fn new() -> Self {
+        Self {
+            computed_values: HashMap::new(),
+            dependencies: HashMap::new(),
+            computed_fields: HashSet::new(),
+        }
+    }
+
+    /// Register a field as computed with its dependencies
+    ///
+    /// - `field_index`: the field that is computed (display-only)
+    /// - `dependencies`: indices of fields this computed field depends on
+    pub fn register_computed_field(&mut self, field_index: usize, mut dependencies: Vec<usize>) {
+        // Deduplicate dependencies to keep graph lean
+        dependencies.sort_unstable();
+        dependencies.dedup();
+
+        self.computed_fields.insert(field_index);
+        self.dependencies.insert(field_index, dependencies);
+    }
+
+    /// Check if a field is computed (read-only, skip editing/navigation)
+    pub fn is_computed_field(&self, field_index: usize) -> bool {
+        self.computed_fields.contains(&field_index)
+    }
+
+    /// Get cached computed value for a field, if available
+    pub fn get_computed_value(&self, field_index: usize) -> Option<&String> {
+        self.computed_values.get(&field_index)
+    }
+
+    /// Update cached computed value for a field
+    pub fn set_computed_value(&mut self, field_index: usize, value: String) {
+        self.computed_values.insert(field_index, value);
+    }
+
+    /// Get fields that should be recomputed when `changed_field` changed
+    ///
+    /// This scans the dependency graph and returns all computed fields
+    /// that list `changed_field` as a dependency.
+    pub fn fields_to_recompute(&self, changed_field: usize) -> Vec<usize> {
+        self.dependencies
+            .iter()
+            .filter_map(|(field, deps)| {
+                if deps.contains(&changed_field) {
+                    Some(*field)
+                } else {
+                    None
+                }
+            })
+            .collect()
+    }
+
+    /// Iterator over all computed field indices
+    pub fn computed_fields(&self) -> impl Iterator<Item = usize> + '_ {
+        self.computed_fields.iter().copied()
+    }
+}
+
+impl Default for ComputedState {
+    fn default() -> Self {
+        Self::new()
+    }
+}
--- a/canvas/src/data_provider.rs
+++ b/canvas/src/data_provider.rs
@@ -0,0 +1,69 @@
+// src/data_provider.rs
+//! Simplified user interface - only business data, no UI state
+
+#[cfg(feature = "suggestions")]
+use anyhow::Result;
+#[cfg(feature = "suggestions")]
+use async_trait::async_trait;
+
+/// User implements this - only business data, no UI state
+pub trait DataProvider {
+    /// How many fields in the form
+    fn field_count(&self) -> usize;
+
+    /// Get field label/name
+    fn field_name(&self, index: usize) -> &str;
+
+    /// Get field value
+    fn field_value(&self, index: usize) -> &str;
+
+    /// Set field value (library calls this when text changes)
+    fn set_field_value(&mut self, index: usize, value: String);
+
+    /// Check if field supports suggestions (optional)
+    fn supports_suggestions(&self, _field_index: usize) -> bool {
+        false
+    }
+
+    /// Get display value (for password masking, etc.) - optional
+    fn display_value(&self, _index: usize) -> Option<&str> {
+        None // Default: use actual value
+    }
+
+    /// Get validation configuration for a field (optional)
+    /// Only available when the 'validation' feature is enabled
+    #[cfg(feature = "validation")]
+    fn validation_config(&self, _field_index: usize) -> Option<crate::validation::ValidationConfig> {
+        None
+    }
+
+    /// Check if field is computed (display-only, skip in navigation)
+    /// Default: not computed
+    #[cfg(feature = "computed")]
+    fn is_computed_field(&self, _field_index: usize) -> bool {
+        false
+    }
+
+    /// Get computed field value if this is a computed field.
+    /// Returns None for regular fields. Default: not computed.
+    #[cfg(feature = "computed")]
+    fn computed_field_value(&self, _field_index: usize) -> Option<String> {
+        None
+    }
+}
+
+/// Optional: User implements this for suggestions data
+#[cfg(feature = "suggestions")]
+#[async_trait]
+pub trait SuggestionsProvider {
+    /// Fetch suggestions (user's business logic)
+    async fn fetch_suggestions(&mut self, field_index: usize, query: &str)
+        -> Result<Vec<SuggestionItem>>;
+}
+
+#[cfg(feature = "suggestions")]
+#[derive(Debug, Clone)]
+pub struct SuggestionItem {
+    pub display_text: String,
+    pub value_to_store: String,
+}
--- a/canvas/src/editor/computed_helpers.rs
+++ b/canvas/src/editor/computed_helpers.rs
@@ -0,0 +1,111 @@
+// src/editor/computed_helpers.rs
+
+use crate::computed::{ComputedContext, ComputedProvider, ComputedState};
+use crate::editor::FormEditor;
+use crate::DataProvider;
+
+impl<D: DataProvider> FormEditor<D> {
+    #[cfg(feature = "computed")]
+    pub fn set_computed_provider<C>(&mut self, mut provider: C)
+    where
+        C: ComputedProvider,
+    {
+        self.ui_state.computed = Some(ComputedState::new());
+
+        let field_count = self.data_provider.field_count();
+        for field_index in 0..field_count {
+            if provider.handles_field(field_index) {
+                let deps = provider.field_dependencies(field_index);
+                if let Some(computed_state) = &mut self.ui_state.computed {
+                    computed_state.register_computed_field(field_index, deps);
+                }
+            }
+        }
+
+        self.recompute_all_fields(&mut provider);
+    }
+
+    #[cfg(feature = "computed")]
+    pub fn recompute_fields<C>(
+        &mut self,
+        provider: &mut C,
+        field_indices: &[usize],
+    ) where
+        C: ComputedProvider,
+    {
+        if let Some(computed_state) = &mut self.ui_state.computed {
+            let field_values: Vec<String> = (0..self.data_provider.field_count())
+                .map(|i| {
+                    if computed_state.is_computed_field(i) {
+                        computed_state
+                            .get_computed_value(i)
+                            .cloned()
+                            .unwrap_or_default()
+                    } else {
+                        self.data_provider.field_value(i).to_string()
+                    }
+                })
+                .collect();
+
+            let field_refs: Vec<&str> =
+                field_values.iter().map(|s| s.as_str()).collect();
+
+            for &field_index in field_indices {
+                if provider.handles_field(field_index) {
+                    let context = ComputedContext {
+                        field_values: &field_refs,
+                        target_field: field_index,
+                        current_field: Some(self.ui_state.current_field),
+                    };
+
+                    let computed_value = provider.compute_field(context);
+                    computed_state.set_computed_value(
+                        field_index,
+                        computed_value,
+                    );
+                }
+            }
+        }
+    }
+
+    #[cfg(feature = "computed")]
+    pub fn recompute_all_fields<C>(&mut self, provider: &mut C)
+    where
+        C: ComputedProvider,
+    {
+        if let Some(computed_state) = &self.ui_state.computed {
+            let computed_fields: Vec<usize> =
+                computed_state.computed_fields().collect();
+            self.recompute_fields(provider, &computed_fields);
+        }
+    }
+
+    #[cfg(feature = "computed")]
+    pub fn on_field_changed<C>(
+        &mut self,
+        provider: &mut C,
+        changed_field: usize,
+    ) where
+        C: ComputedProvider,
+    {
+        if let Some(computed_state) = &self.ui_state.computed {
+            let fields_to_update =
+                computed_state.fields_to_recompute(changed_field);
+            if !fields_to_update.is_empty() {
+                self.recompute_fields(provider, &fields_to_update);
+            }
+        }
+    }
+
+    #[cfg(feature = "computed")]
+    pub fn effective_field_value(&self, field_index: usize) -> String {
+        if let Some(computed_state) = &self.ui_state.computed {
+            if let Some(computed_value) =
+                computed_state.get_computed_value(field_index)
+            {
+                return computed_value.clone();
+            }
+        }
+        self.data_provider.field_value(field_index).to_string()
+    }
+}
--- a/canvas/src/editor/core.rs
+++ b/canvas/src/editor/core.rs
@@ -0,0 +1,122 @@
+// src/editor/core.rs
+
+#[cfg(feature = "cursor-style")]
+use crate::canvas::CursorManager;
+
+use crate::canvas::modes::AppMode;
+use crate::canvas::state::EditorState;
+use crate::DataProvider;
+#[cfg(feature = "suggestions")]
+use crate::SuggestionItem;
+
+pub struct FormEditor<D: DataProvider> {
+    pub(crate) ui_state: EditorState,
+    pub(crate) data_provider: D,
+    #[cfg(feature = "suggestions")]
+    pub(crate) suggestions: Vec<SuggestionItem>,
+
+    #[cfg(feature = "validation")]
+    pub(crate) external_validation_callback: Option<
+        Box<
+            dyn FnMut(usize, &str) -> crate::validation::ExternalValidationState
+                + Send
+                + Sync,
+        >,
+    >,
+}
+
+impl<D: DataProvider> FormEditor<D> {
+    // Make helpers visible to sibling modules in this crate
+    pub(crate) fn char_to_byte_index(s: &str, char_idx: usize) -> usize {
+        s.char_indices()
+            .nth(char_idx)
+            .map(|(byte_idx, _)| byte_idx)
+            .unwrap_or_else(|| s.len())
+    }
+
+    #[allow(dead_code)]
+    pub(crate) fn byte_to_char_index(s: &str, byte_idx: usize) -> usize {
+        s[..byte_idx].chars().count()
+    }
+
+    pub fn new(data_provider: D) -> Self {
+        let editor = Self {
+            ui_state: EditorState::new(),
+            data_provider,
+            #[cfg(feature = "suggestions")]
+            suggestions: Vec::new(),
+            #[cfg(feature = "validation")]
+            external_validation_callback: None,
+        };
+
+        #[cfg(feature = "validation")]
+        {
+            let mut editor = editor;
+            editor.initialize_validation();
+            editor
+        }
+        #[cfg(not(feature = "validation"))]
+        {
+            editor
+        }
+    }
+
+    // Library-internal, used by multiple modules
+    pub(crate) fn current_text(&self) -> &str {
+        let field_index = self.ui_state.current_field;
+        if field_index < self.data_provider.field_count() {
+            self.data_provider.field_value(field_index)
+        } else {
+            ""
+        }
+    }
+
+    // Read-only getters
+    pub fn current_field(&self) -> usize {
+        self.ui_state.current_field()
+    }
+    pub fn cursor_position(&self) -> usize {
+        self.ui_state.cursor_position()
+    }
+    pub fn mode(&self) -> AppMode {
+        self.ui_state.mode()
+    }
+    #[cfg(feature = "suggestions")]
+    pub fn is_suggestions_active(&self) -> bool {
+        self.ui_state.is_suggestions_active()
+    }
+    pub fn ui_state(&self) -> &EditorState {
+        &self.ui_state
+    }
+    pub fn data_provider(&self) -> &D {
+        &self.data_provider
+    }
+    pub fn data_provider_mut(&mut self) -> &mut D {
+        &mut self.data_provider
+    }
+    #[cfg(feature = "suggestions")]
+    pub fn suggestions(&self) -> &[SuggestionItem] {
+        &self.suggestions
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn validation_state(&self) -> &crate::validation::ValidationState {
+        self.ui_state.validation_state()
+    }
+
+    // Cursor cleanup
+    #[cfg(feature = "cursor-style")]
+    pub fn cleanup_cursor(&self) -> std::io::Result<()> {
+        CursorManager::reset()
+    }
+    #[cfg(not(feature = "cursor-style"))]
+    pub fn cleanup_cursor(&self) -> std::io::Result<()> {
+        Ok(())
+    }
+}
+
+impl<D: DataProvider> Drop for FormEditor<D> {
+    fn drop(&mut self) {
+        let _ = self.cleanup_cursor();
+    }
+}
--- a/canvas/src/editor/display.rs
+++ b/canvas/src/editor/display.rs
@@ -0,0 +1,123 @@
+// src/editor/display.rs
+
+use crate::canvas::modes::AppMode;
+use crate::editor::FormEditor;
+use crate::DataProvider;
+
+impl<D: DataProvider> FormEditor<D> {
+    /// Get current field text for display.
+    /// Policies documented in original file.
+    #[cfg(feature = "validation")]
+    pub fn current_display_text(&self) -> String {
+        let field_index = self.ui_state.current_field;
+        let raw = if field_index < self.data_provider.field_count() {
+            self.data_provider.field_value(field_index)
+        } else {
+            ""
+        };
+
+        if let Some(cfg) = self.ui_state.validation.get_field_config(field_index) {
+            if cfg.custom_formatter.is_none() {
+                if let Some(mask) = &cfg.display_mask {
+                    return mask.apply_to_display(raw);
+                }
+            }
+
+            if cfg.custom_formatter.is_some() {
+                if matches!(self.ui_state.current_mode, AppMode::Edit) {
+                    return raw.to_string();
+                }
+                if let Some((formatted, _mapper, _warning)) =
+                    cfg.run_custom_formatter(raw)
+                {
+                    return formatted;
+                }
+            }
+
+            if let Some(mask) = &cfg.display_mask {
+                return mask.apply_to_display(raw);
+            }
+        }
+
+        raw.to_string()
+    }
+
+    /// Get effective display text for any field index (Feature 4 + masks).
+    #[cfg(feature = "validation")]
+    pub fn display_text_for_field(&self, field_index: usize) -> String {
+        let raw = if field_index < self.data_provider.field_count() {
+            self.data_provider.field_value(field_index)
+        } else {
+            ""
+        };
+
+        if let Some(cfg) = self.ui_state.validation.get_field_config(field_index) {
+            if cfg.custom_formatter.is_none() {
+                if let Some(mask) = &cfg.display_mask {
+                    return mask.apply_to_display(raw);
+                }
+            }
+
+            if cfg.custom_formatter.is_some() {
+                if field_index == self.ui_state.current_field
+                    && matches!(self.ui_state.current_mode, AppMode::Edit)
+                {
+                    return raw.to_string();
+                }
+                if let Some((formatted, _mapper, _warning)) =
+                    cfg.run_custom_formatter(raw)
+                {
+                    return formatted;
+                }
+            }
+
+            if let Some(mask) = &cfg.display_mask {
+                return mask.apply_to_display(raw);
+            }
+        }
+
+        raw.to_string()
+    }
+
+    /// Map raw cursor to display position (formatter/mask aware).
+    pub fn display_cursor_position(&self) -> usize {
+        let current_text = self.current_text();
+        let char_count = current_text.chars().count();
+
+        let raw_pos = match self.ui_state.current_mode {
+            AppMode::Edit => self.ui_state.cursor_pos.min(char_count),
+            _ => {
+                if char_count == 0 {
+                    0
+                } else {
+                    self.ui_state
+                        .cursor_pos
+                        .min(char_count.saturating_sub(1))
+                }
+            }
+        };
+
+        #[cfg(feature = "validation")]
+        {
+            let field_index = self.ui_state.current_field;
+            if let Some(cfg) = self.ui_state.validation.get_field_config(field_index) {
+                if !matches!(self.ui_state.current_mode, AppMode::Edit) {
+                    if let Some((formatted, mapper, _)) =
+                        cfg.run_custom_formatter(current_text)
+                    {
+                        return mapper.raw_to_formatted(
+                            current_text,
+                            &formatted,
+                            raw_pos,
+                        );
+                    }
+                }
+                if let Some(mask) = &cfg.display_mask {
+                    return mask.raw_pos_to_display_pos(raw_pos);
+                }
+            }
+        }
+
+        raw_pos
+    }
+}
--- a/canvas/src/editor/editing.rs
+++ b/canvas/src/editor/editing.rs
@@ -0,0 +1,348 @@
+// src/editor/editing.rs
+
+use crate::editor::FormEditor;
+use crate::DataProvider;
+
+impl<D: DataProvider> FormEditor<D> {
+    /// Open new line below (vim o)
+    pub fn open_line_below(&mut self) -> anyhow::Result<()> {
+        // paste the method body unchanged from editor.rs
+        // (exact code from your VIM COMMANDS: o and O section)
+        let field_count = self.data_provider.field_count();
+        if field_count == 0 {
+            return Ok(());
+        }
+        let next_field = (self.ui_state.current_field + 1)
+            .min(field_count.saturating_sub(1));
+        self.transition_to_field(next_field)?;
+        self.ui_state.cursor_pos = 0;
+        self.ui_state.ideal_cursor_column = 0;
+        self.enter_edit_mode();
+        Ok(())
+    }
+
+    /// Open new line above (vim O)
+    pub fn open_line_above(&mut self) -> anyhow::Result<()> {
+        let prev_field = self.ui_state.current_field.saturating_sub(1);
+        self.transition_to_field(prev_field)?;
+        self.ui_state.cursor_pos = 0;
+        self.ui_state.ideal_cursor_column = 0;
+        self.enter_edit_mode();
+        Ok(())
+    }
+
+    /// Handle character insertion (mask/limit-aware)
+    pub fn insert_char(&mut self, ch: char) -> anyhow::Result<()> {
+        // paste entire insert_char body unchanged
+        if self.ui_state.current_mode != crate::canvas::modes::AppMode::Edit
+        {
+            return Ok(());
+        }
+
+        #[cfg(feature = "validation")]
+        let field_index = self.ui_state.current_field;
+        #[cfg(feature = "validation")]
+        let raw_cursor_pos = self.ui_state.cursor_pos;
+        #[cfg(feature = "validation")]
+        let current_raw_text = self.data_provider.field_value(field_index);
+
+        #[cfg(not(feature = "validation"))]
+        let field_index = self.ui_state.current_field;
+        #[cfg(not(feature = "validation"))]
+        let raw_cursor_pos = self.ui_state.cursor_pos;
+        #[cfg(not(feature = "validation"))]
+        let current_raw_text = self.data_provider.field_value(field_index);
+
+        #[cfg(feature = "validation")]
+        {
+            if let Some(cfg) = self.ui_state.validation.get_field_config(
+                field_index,
+            ) {
+                if let Some(mask) = &cfg.display_mask {
+                    let display_cursor_pos =
+                        mask.raw_pos_to_display_pos(raw_cursor_pos);
+
+                    let pattern_char_len = mask.pattern().chars().count();
+                    if display_cursor_pos >= pattern_char_len {
+                        return Ok(());
+                    }
+
+                    if !mask.is_input_position(display_cursor_pos) {
+                        return Ok(());
+                    }
+
+                    let input_slots = (0..pattern_char_len)
+                        .filter(|&pos| mask.is_input_position(pos))
+                        .count();
+                    if current_raw_text.chars().count() >= input_slots {
+                        return Ok(());
+                    }
+                }
+            }
+        }
+
+        #[cfg(feature = "validation")]
+        {
+            let vr = self.ui_state.validation.validate_char_insertion(
+                field_index,
+                current_raw_text,
+                raw_cursor_pos,
+                ch,
+            );
+            if !vr.is_acceptable() {
+                return Ok(());
+            }
+        }
+
+        let new_raw_text = {
+            let mut temp = current_raw_text.to_string();
+            let byte_pos = Self::char_to_byte_index(
+                current_raw_text,
+                raw_cursor_pos,
+            );
+            temp.insert(byte_pos, ch);
+            temp
+        };
+
+        #[cfg(feature = "validation")]
+        {
+            if let Some(cfg) = self.ui_state.validation.get_field_config(
+                field_index,
+            ) {
+                if let Some(limits) = &cfg.character_limits {
+                    if let Some(result) = limits.validate_content(&new_raw_text)
+                    {
+                        if !result.is_acceptable() {
+                            return Ok(());
+                        }
+                    }
+                }
+                if let Some(mask) = &cfg.display_mask {
+                    let pattern_char_len = mask.pattern().chars().count();
+                    let input_slots = (0..pattern_char_len)
+                        .filter(|&pos| mask.is_input_position(pos))
+                        .count();
+                    if new_raw_text.chars().count() > input_slots {
+                        return Ok(());
+                    }
+                }
+            }
+        }
+
+        self.data_provider
+            .set_field_value(field_index, new_raw_text.clone());
+
+        #[cfg(feature = "validation")]
+        {
+            if let Some(cfg) = self.ui_state.validation.get_field_config(
+                field_index,
+            ) {
+                if let Some(mask) = &cfg.display_mask {
+                    let new_raw_pos = raw_cursor_pos + 1;
+                    let display_pos = mask.raw_pos_to_display_pos(new_raw_pos);
+                    let next_input_display =
+                        mask.next_input_position(display_pos);
+                    let next_raw_pos =
+                        mask.display_pos_to_raw_pos(next_input_display);
+                    let max_raw = new_raw_text.chars().count();
+
+                    self.ui_state.cursor_pos = next_raw_pos.min(max_raw);
+                    self.ui_state.ideal_cursor_column =
+                        self.ui_state.cursor_pos;
+                    return Ok(());
+                }
+            }
+        }
+
+        self.ui_state.cursor_pos = raw_cursor_pos + 1;
+        self.ui_state.ideal_cursor_column = self.ui_state.cursor_pos;
+        Ok(())
+    }
+
+    /// Delete backward (backspace)
+    pub fn delete_backward(&mut self) -> anyhow::Result<()> {
+        // paste entire delete_backward body unchanged
+        if self.ui_state.current_mode != crate::canvas::modes::AppMode::Edit
+        {
+            return Ok(());
+        }
+        if self.ui_state.cursor_pos == 0 {
+            return Ok(());
+        }
+
+        let field_index = self.ui_state.current_field;
+        let mut current_text =
+            self.data_provider.field_value(field_index).to_string();
+
+        let new_cursor = self.ui_state.cursor_pos.saturating_sub(1);
+
+        let start = Self::char_to_byte_index(
+            &current_text,
+            self.ui_state.cursor_pos - 1,
+        );
+        let end =
+            Self::char_to_byte_index(&current_text, self.ui_state.cursor_pos);
+        current_text.replace_range(start..end, "");
+        self.data_provider
+            .set_field_value(field_index, current_text.clone());
+
+        #[cfg(feature = "validation")]
+        let mut target_cursor = new_cursor;
+        #[cfg(not(feature = "validation"))]
+        let target_cursor = new_cursor;
+
+        #[cfg(feature = "validation")]
+        {
+            if let Some(cfg) = self.ui_state.validation.get_field_config(
+                field_index,
+            ) {
+                if let Some(mask) = &cfg.display_mask {
+                    let display_pos =
+                        mask.raw_pos_to_display_pos(new_cursor);
+                    if let Some(prev_input) =
+                        mask.prev_input_position(display_pos)
+                    {
+                        target_cursor =
+                            mask.display_pos_to_raw_pos(prev_input);
+                    }
+                }
+            }
+        }
+
+        self.ui_state.cursor_pos = target_cursor;
+        self.ui_state.ideal_cursor_column = target_cursor;
+
+        #[cfg(feature = "validation")]
+        {
+            let _ = self.ui_state.validation.validate_field_content(
+                field_index,
+                &current_text,
+            );
+        }
+
+        Ok(())
+    }
+
+    /// Delete forward (Delete key)
+    pub fn delete_forward(&mut self) -> anyhow::Result<()> {
+        // paste entire delete_forward body unchanged
+        if self.ui_state.current_mode != crate::canvas::modes::AppMode::Edit
+        {
+            return Ok(());
+        }
+
+        let field_index = self.ui_state.current_field;
+        let mut current_text =
+            self.data_provider.field_value(field_index).to_string();
+
+        if self.ui_state.cursor_pos < current_text.chars().count() {
+            let start = Self::char_to_byte_index(
+                &current_text,
+                self.ui_state.cursor_pos,
+            );
+            let end = Self::char_to_byte_index(
+                &current_text,
+                self.ui_state.cursor_pos + 1,
+            );
+            current_text.replace_range(start..end, "");
+            self.data_provider
+                .set_field_value(field_index, current_text.clone());
+
+            #[cfg(feature = "validation")]
+            let mut target_cursor = self.ui_state.cursor_pos;
+            #[cfg(not(feature = "validation"))]
+            let target_cursor = self.ui_state.cursor_pos;
+
+            #[cfg(feature = "validation")]
+            {
+                if let Some(cfg) = self.ui_state.validation.get_field_config(
+                    field_index,
+                ) {
+                    if let Some(mask) = &cfg.display_mask {
+                        let display_pos =
+                            mask.raw_pos_to_display_pos(
+                                self.ui_state.cursor_pos,
+                            );
+                        let next_input =
+                            mask.next_input_position(display_pos);
+                        target_cursor = mask
+                            .display_pos_to_raw_pos(next_input)
+                            .min(current_text.chars().count());
+                    }
+                }
+            }
+
+            self.ui_state.cursor_pos = target_cursor;
+            self.ui_state.ideal_cursor_column = target_cursor;
+
+            #[cfg(feature = "validation")]
+            {
+                let _ = self.ui_state.validation.validate_field_content(
+                    field_index,
+                    &current_text,
+                );
+            }
+        }
+
+        Ok(())
+    }
+
+    /// Enter edit mode with cursor positioned for append (vim 'a')
+    pub fn enter_append_mode(&mut self) {
+        // paste body unchanged
+        let current_text = self.current_text();
+
+        let char_len = current_text.chars().count();
+        let append_pos = if current_text.is_empty() {
+            0
+        } else {
+            (self.ui_state.cursor_pos + 1).min(char_len)
+        };
+
+        self.ui_state.cursor_pos = append_pos;
+        self.ui_state.ideal_cursor_column = append_pos;
+
+        self.set_mode(crate::canvas::modes::AppMode::Edit);
+    }
+
+    /// Set current field value (validates under feature flag)
+    pub fn set_current_field_value(&mut self, value: String) {
+        let field_index = self.ui_state.current_field;
+        self.data_provider.set_field_value(field_index, value.clone());
+        self.ui_state.cursor_pos = 0;
+        self.ui_state.ideal_cursor_column = 0;
+
+        #[cfg(feature = "validation")]
+        {
+            let _ = self
+                .ui_state
+                .validation
+                .validate_field_content(field_index, &value);
+        }
+    }
+
+    /// Set specific field value by index (validates under feature flag)
+    pub fn set_field_value(&mut self, field_index: usize, value: String) {
+        if field_index < self.data_provider.field_count() {
+            self.data_provider
+                .set_field_value(field_index, value.clone());
+            if field_index == self.ui_state.current_field {
+                self.ui_state.cursor_pos = 0;
+                self.ui_state.ideal_cursor_column = 0;
+            }
+
+            #[cfg(feature = "validation")]
+            {
+                let _ = self
+                    .ui_state
+                    .validation
+                    .validate_field_content(field_index, &value);
+            }
+        }
+    }
+
+    /// Clear the current field
+    pub fn clear_current_field(&mut self) {
+        self.set_current_field_value(String::new());
+    }
+}
--- a/canvas/src/editor/mod.rs
+++ b/canvas/src/editor/mod.rs
@@ -0,0 +1,21 @@
+// src/editor/mod.rs
+// Only module declarations and re-exports.
+
+pub mod core;
+pub mod display;
+pub mod editing;
+pub mod movement;
+pub mod navigation;
+pub mod mode;
+
+#[cfg(feature = "suggestions")]
+pub mod suggestions;
+
+#[cfg(feature = "validation")]
+pub mod validation_helpers;
+
+#[cfg(feature = "computed")]
+pub mod computed_helpers;
+
+// Re-export the main type
+pub use core::FormEditor;
--- a/canvas/src/editor/mode.rs
+++ b/canvas/src/editor/mode.rs
@@ -0,0 +1,222 @@
+// src/editor/mode.rs
+
+#[cfg(feature = "cursor-style")]
+use crate::canvas::CursorManager;
+
+use crate::canvas::modes::AppMode;
+use crate::canvas::state::SelectionState;
+use crate::editor::FormEditor;
+use crate::DataProvider;
+
+impl<D: DataProvider> FormEditor<D> {
+    /// Change mode (for vim compatibility)
+    pub fn set_mode(&mut self, mode: AppMode) {
+        match (self.ui_state.current_mode, mode) {
+            (AppMode::ReadOnly, AppMode::Highlight) => {
+                self.enter_highlight_mode();
+            }
+            (AppMode::Highlight, AppMode::ReadOnly) => {
+                self.exit_highlight_mode();
+            }
+            (_, new_mode) => {
+                self.ui_state.current_mode = new_mode;
+                if new_mode != AppMode::Highlight {
+                    self.ui_state.selection = SelectionState::None;
+                }
+
+                #[cfg(feature = "cursor-style")]
+                {
+                    let _ = CursorManager::update_for_mode(new_mode);
+                }
+            }
+        }
+    }
+
+    /// Exit edit mode to read-only mode (vim Escape)
+    pub fn exit_edit_mode(&mut self) -> anyhow::Result<()> {
+        #[cfg(feature = "validation")]
+        {
+            let current_text = self.current_text();
+            if !self.ui_state.validation.allows_field_switch(
+                self.ui_state.current_field,
+                current_text,
+            ) {
+                if let Some(reason) = self.ui_state.validation
+                    .field_switch_block_reason(
+                        self.ui_state.current_field,
+                        current_text,
+                    )
+                {
+                    self.ui_state
+                        .validation
+                        .set_last_switch_block(reason.clone());
+                    return Err(anyhow::anyhow!(
+                        "Cannot exit edit mode: {}",
+                        reason
+                    ));
+                }
+            }
+        }
+
+        let current_text = self.current_text();
+        if !current_text.is_empty() {
+            let max_normal_pos =
+                current_text.chars().count().saturating_sub(1);
+            if self.ui_state.cursor_pos > max_normal_pos {
+                self.ui_state.cursor_pos = max_normal_pos;
+                self.ui_state.ideal_cursor_column = self.ui_state.cursor_pos;
+            }
+        }
+
+        #[cfg(feature = "validation")]
+        {
+            let field_index = self.ui_state.current_field;
+            if let Some(cfg) =
+                self.ui_state.validation.get_field_config(field_index)
+            {
+                if cfg.external_validation_enabled {
+                    let text = self.current_text().to_string();
+                    if !text.is_empty() {
+                        self.set_external_validation(
+                            field_index,
+                            crate::validation::ExternalValidationState::Validating,
+                        );
+                        if let Some(cb) =
+                            self.external_validation_callback.as_mut()
+                        {
+                            let final_state = cb(field_index, &text);
+                            self.set_external_validation(field_index, final_state);
+                        }
+                    }
+                }
+            }
+        }
+
+        self.set_mode(AppMode::ReadOnly);
+        #[cfg(feature = "suggestions")]
+        {
+            self.close_suggestions();
+        }
+        Ok(())
+    }
+
+    /// Enter edit mode from read-only mode (vim i/a/o)
+    pub fn enter_edit_mode(&mut self) {
+        #[cfg(feature = "computed")]
+        {
+            if let Some(computed_state) = &self.ui_state.computed {
+                if computed_state.is_computed_field(self.ui_state.current_field)
+                {
+                    return;
+                }
+            }
+        }
+        self.set_mode(AppMode::Edit);
+    }
+
+    // -------------------- Highlight/Visual mode -------------------------
+
+    pub fn enter_highlight_mode(&mut self) {
+        if self.ui_state.current_mode == AppMode::ReadOnly {
+            self.ui_state.current_mode = AppMode::Highlight;
+            self.ui_state.selection = SelectionState::Characterwise {
+                anchor: (self.ui_state.current_field, self.ui_state.cursor_pos),
+            };
+
+            #[cfg(feature = "cursor-style")]
+            {
+                let _ = CursorManager::update_for_mode(AppMode::Highlight);
+            }
+        }
+    }
+
+    pub fn enter_highlight_line_mode(&mut self) {
+        if self.ui_state.current_mode == AppMode::ReadOnly {
+            self.ui_state.current_mode = AppMode::Highlight;
+            self.ui_state.selection =
+                SelectionState::Linewise { anchor_field: self.ui_state.current_field };
+
+            #[cfg(feature = "cursor-style")]
+            {
+                let _ = CursorManager::update_for_mode(AppMode::Highlight);
+            }
+        }
+    }
+
+    pub fn exit_highlight_mode(&mut self) {
+        if self.ui_state.current_mode == AppMode::Highlight {
+            self.ui_state.current_mode = AppMode::ReadOnly;
+            self.ui_state.selection = SelectionState::None;
+
+            #[cfg(feature = "cursor-style")]
+            {
+                let _ = CursorManager::update_for_mode(AppMode::ReadOnly);
+            }
+        }
+    }
+
+    pub fn is_highlight_mode(&self) -> bool {
+        self.ui_state.current_mode == AppMode::Highlight
+    }
+
+    pub fn selection_state(&self) -> &SelectionState {
+        &self.ui_state.selection
+    }
+
+    // Visual-mode movements reuse existing movement methods
+    pub fn move_left_with_selection(&mut self) {
+        let _ = self.move_left();
+    }
+
+    pub fn move_right_with_selection(&mut self) {
+        let _ = self.move_right();
+    }
+
+    pub fn move_up_with_selection(&mut self) {
+        let _ = self.move_up();
+    }
+
+    pub fn move_down_with_selection(&mut self) {
+        let _ = self.move_down();
+    }
+
+    pub fn move_word_next_with_selection(&mut self) {
+        self.move_word_next();
+    }
+
+    pub fn move_word_end_with_selection(&mut self) {
+        self.move_word_end();
+    }
+
+    pub fn move_word_prev_with_selection(&mut self) {
+        self.move_word_prev();
+    }
+
+    pub fn move_word_end_prev_with_selection(&mut self) {
+        self.move_word_end_prev();
+    }
+
+    pub fn move_big_word_next_with_selection(&mut self) {
+        self.move_big_word_next();
+    }
+
+    pub fn move_big_word_end_with_selection(&mut self) {
+        self.move_big_word_end();
+    }
+
+    pub fn move_big_word_prev_with_selection(&mut self) {
+        self.move_big_word_prev();
+    }
+
+    pub fn move_big_word_end_prev_with_selection(&mut self) {
+        self.move_big_word_end_prev();
+    }
+
+    pub fn move_line_start_with_selection(&mut self) {
+        self.move_line_start();
+    }
+
+    pub fn move_line_end_with_selection(&mut self) {
+        self.move_line_end();
+    }
+}
--- a/canvas/src/editor/movement.rs
+++ b/canvas/src/editor/movement.rs
@@ -0,0 +1,690 @@
+// src/editor/movement.rs
+
+use crate::canvas::actions::movement::line::{
+    line_end_position, line_start_position,
+};
+use crate::canvas::modes::AppMode;
+use crate::editor::FormEditor;
+use crate::DataProvider;
+use crate::canvas::actions::movement::word::{
+    find_last_big_word_start_in_field, find_last_word_start_in_field,
+};
+
+impl<D: DataProvider> FormEditor<D> {
+    /// Move cursor left within current field (mask-aware)
+    pub fn move_left(&mut self) -> anyhow::Result<()> {
+        #[cfg(feature = "validation")]
+        let mut moved = false;
+        #[cfg(not(feature = "validation"))]
+        let moved = false;
+
+        #[cfg(feature = "validation")]
+        {
+            let field_index = self.ui_state.current_field;
+            if let Some(cfg) =
+                self.ui_state.validation.get_field_config(field_index)
+            {
+                if let Some(mask) = &cfg.display_mask {
+                    let display_pos =
+                        mask.raw_pos_to_display_pos(self.ui_state.cursor_pos);
+                    if let Some(prev_input) =
+                        mask.prev_input_position(display_pos)
+                    {
+                        let raw_pos =
+                            mask.display_pos_to_raw_pos(prev_input);
+                        let max_pos = self.current_text().chars().count();
+                        self.ui_state.cursor_pos = raw_pos.min(max_pos);
+                        self.ui_state.ideal_cursor_column =
+                            self.ui_state.cursor_pos;
+                        moved = true;
+                    } else {
+                        self.ui_state.cursor_pos = 0;
+                        self.ui_state.ideal_cursor_column = 0;
+                        moved = true;
+                    }
+                }
+            }
+        }
+
+        if !moved {
+            if self.ui_state.cursor_pos > 0 {
+                self.ui_state.cursor_pos -= 1;
+                self.ui_state.ideal_cursor_column = self.ui_state.cursor_pos;
+            }
+        }
+        Ok(())
+    }
+
+    /// Move cursor right within current field (mask-aware)
+    pub fn move_right(&mut self) -> anyhow::Result<()> {
+        #[cfg(feature = "validation")]
+        let mut moved = false;
+        #[cfg(not(feature = "validation"))]
+        let moved = false;
+
+        #[cfg(feature = "validation")]
+        {
+            let field_index = self.ui_state.current_field;
+            if let Some(cfg) =
+                self.ui_state.validation.get_field_config(field_index)
+            {
+                if let Some(mask) = &cfg.display_mask {
+                    let display_pos =
+                        mask.raw_pos_to_display_pos(self.ui_state.cursor_pos);
+                    let next_display_pos = mask.next_input_position(display_pos);
+                    let next_pos =
+                        mask.display_pos_to_raw_pos(next_display_pos);
+                    let max_pos = self.current_text().chars().count();
+                    self.ui_state.cursor_pos = next_pos.min(max_pos);
+                    self.ui_state.ideal_cursor_column =
+                        self.ui_state.cursor_pos;
+                    moved = true;
+                }
+            }
+        }
+
+        if !moved {
+            let max_pos = self.current_text().chars().count();
+            if self.ui_state.cursor_pos < max_pos {
+                self.ui_state.cursor_pos += 1;
+                self.ui_state.ideal_cursor_column = self.ui_state.cursor_pos;
+            }
+        }
+        Ok(())
+    }
+
+    /// Move to start of current field (vim 0)
+    pub fn move_line_start(&mut self) {
+        let new_pos = line_start_position();
+        self.ui_state.cursor_pos = new_pos;
+        self.ui_state.ideal_cursor_column = new_pos;
+    }
+
+    /// Move to end of current field (vim $)
+    pub fn move_line_end(&mut self) {
+        let current_text = self.current_text();
+        let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+
+        let new_pos = line_end_position(current_text, is_edit_mode);
+        self.ui_state.cursor_pos = new_pos;
+        self.ui_state.ideal_cursor_column = new_pos;
+    }
+
+    /// Set cursor to exact position (for f/F/t/T etc.)
+    pub fn set_cursor_position(&mut self, position: usize) {
+        let current_text = self.current_text();
+        let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+
+        let char_len = current_text.chars().count();
+        let max_pos = if is_edit_mode {
+            char_len
+        } else {
+            char_len.saturating_sub(1)
+        };
+
+        let clamped_pos = position.min(max_pos);
+        self.ui_state.cursor_pos = clamped_pos;
+        self.ui_state.ideal_cursor_column = clamped_pos;
+    }
+}
+
+
+impl<D: DataProvider> FormEditor<D> {
+    /// Move to start of next word (vim w) - can cross field boundaries
+    pub fn move_word_next(&mut self) {
+        use crate::canvas::actions::movement::word::find_next_word_start;
+        let current_text = self.current_text();
+
+        if current_text.is_empty() {
+            // Empty field - try to move to next field
+            if self.move_down().is_ok() {
+                // Successfully moved to next field, try to find first word
+                let new_text = self.current_text();
+                if !new_text.is_empty() {
+                    let first_word_pos = if new_text.chars().next().map_or(false, |c| !c.is_whitespace()) {
+                        // Field starts with non-whitespace, go to position 0
+                        0
+                    } else {
+                        // Field starts with whitespace, find first word
+                        find_next_word_start(new_text, 0)
+                    };
+                    let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+                    let char_len = new_text.chars().count();
+                    let final_pos = if is_edit_mode {
+                        first_word_pos.min(char_len)
+                    } else {
+                        first_word_pos.min(char_len.saturating_sub(1))
+                    };
+                    self.ui_state.cursor_pos = final_pos;
+                    self.ui_state.ideal_cursor_column = final_pos;
+                }
+            }
+            return;
+        }
+
+        let current_pos = self.ui_state.cursor_pos;
+        let new_pos = find_next_word_start(current_text, current_pos);
+        
+        // Check if we've hit the end of the current field
+        if new_pos >= current_text.chars().count() {
+            // At end of field - jump to next field and start from beginning
+            if self.move_down().is_ok() {
+                // Successfully moved to next field
+                let new_text = self.current_text();
+                if new_text.is_empty() {
+                    // New field is empty, cursor stays at 0
+                    self.ui_state.cursor_pos = 0;
+                    self.ui_state.ideal_cursor_column = 0;
+                } else {
+                    // Find first word in new field
+                    let first_word_pos = if new_text.chars().next().map_or(false, |c| !c.is_whitespace()) {
+                        // Field starts with non-whitespace, go to position 0
+                        0
+                    } else {
+                        // Field starts with whitespace, find first word
+                        find_next_word_start(new_text, 0)
+                    };
+                    let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+                    let char_len = new_text.chars().count();
+                    let final_pos = if is_edit_mode {
+                        first_word_pos.min(char_len)
+                    } else {
+                        first_word_pos.min(char_len.saturating_sub(1))
+                    };
+                    self.ui_state.cursor_pos = final_pos;
+                    self.ui_state.ideal_cursor_column = final_pos;
+                }
+            }
+            // If move_down() failed, we stay where we are (at end of last field)
+        } else {
+            // Normal word movement within current field
+            let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+            let char_len = current_text.chars().count();
+            let final_pos = if is_edit_mode {
+                new_pos.min(char_len)
+            } else {
+                new_pos.min(char_len.saturating_sub(1))
+            };
+
+            self.ui_state.cursor_pos = final_pos;
+            self.ui_state.ideal_cursor_column = final_pos;
+        }
+    }
+
+    /// Move to start of previous word (vim b) - can cross field boundaries
+    pub fn move_word_prev(&mut self) {
+        use crate::canvas::actions::movement::word::find_prev_word_start;
+        let current_text = self.current_text();
+
+        if current_text.is_empty() {
+            // Empty field - try to move to previous field and find last word
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                // Check if we actually moved to a different field
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        let last_word_start = find_last_word_start_in_field(new_text);
+                        self.ui_state.cursor_pos = last_word_start;
+                        self.ui_state.ideal_cursor_column = last_word_start;
+                    }
+                }
+            }
+            return;
+        }
+
+        let current_pos = self.ui_state.cursor_pos;
+
+        // Special case: if we're at position 0, jump to previous field
+        if current_pos == 0 {
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                // Check if we actually moved to a different field
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        let last_word_start = find_last_word_start_in_field(new_text);
+                        self.ui_state.cursor_pos = last_word_start;
+                        self.ui_state.ideal_cursor_column = last_word_start;
+                    }
+                }
+            }
+            return;
+        }
+
+        // Try to find previous word in current field
+        let new_pos = find_prev_word_start(current_text, current_pos);
+
+        // Check if we actually moved
+        if new_pos < current_pos {
+            // Normal word movement within current field - we found a previous word
+            self.ui_state.cursor_pos = new_pos;
+            self.ui_state.ideal_cursor_column = new_pos;
+        } else {
+            // We didn't move (probably at start of first word), try previous field
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                // Check if we actually moved to a different field
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        let last_word_start = find_last_word_start_in_field(new_text);
+                        self.ui_state.cursor_pos = last_word_start;
+                        self.ui_state.ideal_cursor_column = last_word_start;
+                    }
+                }
+            }
+        }
+    }
+
+    /// Move to end of current/next word (vim e) - can cross field boundaries
+    pub fn move_word_end(&mut self) {
+        use crate::canvas::actions::movement::word::find_word_end;
+        let current_text = self.current_text();
+
+        if current_text.is_empty() {
+            // Empty field - try to move to next field
+            if self.move_down().is_ok() {
+                // Recursively call move_word_end in the new field
+                self.move_word_end();
+            }
+            return;
+        }
+
+        let current_pos = self.ui_state.cursor_pos;
+        let char_len = current_text.chars().count();
+        let new_pos = find_word_end(current_text, current_pos);
+
+        // Check if we didn't move or hit the end of the field
+        if new_pos == current_pos && current_pos + 1 < char_len {
+            // Try next character and find word end from there
+            let next_pos = find_word_end(current_text, current_pos + 1);
+            if next_pos < char_len {
+                let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+                let final_pos = if is_edit_mode {
+                    next_pos.min(char_len)
+                } else {
+                    next_pos.min(char_len.saturating_sub(1))
+                };
+                self.ui_state.cursor_pos = final_pos;
+                self.ui_state.ideal_cursor_column = final_pos;
+                return;
+            }
+        }
+
+        // If we're at or near the end of the field, try next field
+        if new_pos >= char_len.saturating_sub(1) {
+            if self.move_down().is_ok() {
+                // Position at start and find first word end
+                self.ui_state.cursor_pos = 0;
+                self.ui_state.ideal_cursor_column = 0;
+                self.move_word_end();
+            }
+        } else {
+            // Normal word end movement within current field
+            let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+            let final_pos = if is_edit_mode {
+                new_pos.min(char_len)
+            } else {
+                new_pos.min(char_len.saturating_sub(1))
+            };
+
+            self.ui_state.cursor_pos = final_pos;
+            self.ui_state.ideal_cursor_column = final_pos;
+        }
+    }
+
+    /// Move to end of previous word (vim ge) - can cross field boundaries
+    pub fn move_word_end_prev(&mut self) {
+        use crate::canvas::actions::movement::word::{find_prev_word_end, find_last_word_end_in_field};
+        let current_text = self.current_text();
+
+        if current_text.is_empty() {
+            // Empty field - try to move to previous field (but don't recurse)
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                // Check if we actually moved to a different field
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        // Find end of last word in the field
+                        let last_word_end = find_last_word_end_in_field(new_text);
+                        self.ui_state.cursor_pos = last_word_end;
+                        self.ui_state.ideal_cursor_column = last_word_end;
+                    }
+                }
+            }
+            return;
+        }
+
+        let current_pos = self.ui_state.cursor_pos;
+
+        // Special case: if we're at position 0, jump to previous field (but don't recurse)
+        if current_pos == 0 {
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                // Check if we actually moved to a different field
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        let last_word_end = find_last_word_end_in_field(new_text);
+                        self.ui_state.cursor_pos = last_word_end;
+                        self.ui_state.ideal_cursor_column = last_word_end;
+                    }
+                }
+            }
+            return;
+        }
+
+        let new_pos = find_prev_word_end(current_text, current_pos);
+
+        // Only try to cross fields if we didn't move at all (stayed at same position)
+        if new_pos == current_pos {
+            // We didn't move within the current field, try previous field
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                // Check if we actually moved to a different field
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        let last_word_end = find_last_word_end_in_field(new_text);
+                        self.ui_state.cursor_pos = last_word_end;
+                        self.ui_state.ideal_cursor_column = last_word_end;
+                    }
+                }
+            }
+        } else {
+            // Normal word movement within current field
+            let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+            let char_len = current_text.chars().count();
+            let final_pos = if is_edit_mode {
+                new_pos.min(char_len)
+            } else {
+                new_pos.min(char_len.saturating_sub(1))
+            };
+
+            self.ui_state.cursor_pos = final_pos;
+            self.ui_state.ideal_cursor_column = final_pos;
+        }
+    }
+
+    /// Move to start of next big_word (vim W) - can cross field boundaries
+    pub fn move_big_word_next(&mut self) {
+        use crate::canvas::actions::movement::word::find_next_big_word_start;
+        let current_text = self.current_text();
+
+        if current_text.is_empty() {
+            // Empty field - try to move to next field
+            if self.move_down().is_ok() {
+                // Successfully moved to next field, try to find first big_word
+                let new_text = self.current_text();
+                if !new_text.is_empty() {
+                    let first_big_word_pos = if new_text.chars().next().map_or(false, |c| !c.is_whitespace()) {
+                        // Field starts with non-whitespace, go to position 0
+                        0
+                    } else {
+                        // Field starts with whitespace, find first big_word
+                        find_next_big_word_start(new_text, 0)
+                    };
+                    let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+                    let char_len = new_text.chars().count();
+                    let final_pos = if is_edit_mode {
+                        first_big_word_pos.min(char_len)
+                    } else {
+                        first_big_word_pos.min(char_len.saturating_sub(1))
+                    };
+                    self.ui_state.cursor_pos = final_pos;
+                    self.ui_state.ideal_cursor_column = final_pos;
+                }
+            }
+            return;
+        }
+
+        let current_pos = self.ui_state.cursor_pos;
+        let new_pos = find_next_big_word_start(current_text, current_pos);
+
+        // Check if we've hit the end of the current field
+        if new_pos >= current_text.chars().count() {
+            // At end of field - jump to next field and start from beginning
+            if self.move_down().is_ok() {
+                // Successfully moved to next field
+                let new_text = self.current_text();
+                if new_text.is_empty() {
+                    // New field is empty, cursor stays at 0
+                    self.ui_state.cursor_pos = 0;
+                    self.ui_state.ideal_cursor_column = 0;
+                } else {
+                    // Find first big_word in new field
+                    let first_big_word_pos = if new_text.chars().next().map_or(false, |c| !c.is_whitespace()) {
+                        // Field starts with non-whitespace, go to position 0
+                        0
+                    } else {
+                        // Field starts with whitespace, find first big_word
+                        find_next_big_word_start(new_text, 0)
+                    };
+                    let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+                    let char_len = new_text.chars().count();
+                    let final_pos = if is_edit_mode {
+                        first_big_word_pos.min(char_len)
+                    } else {
+                        first_big_word_pos.min(char_len.saturating_sub(1))
+                    };
+                    self.ui_state.cursor_pos = final_pos;
+                    self.ui_state.ideal_cursor_column = final_pos;
+                }
+            }
+            // If move_down() failed, we stay where we are (at end of last field)
+        } else {
+            // Normal big_word movement within current field
+            let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+            let char_len = current_text.chars().count();
+            let final_pos = if is_edit_mode {
+                new_pos.min(char_len)
+            } else {
+                new_pos.min(char_len.saturating_sub(1))
+            };
+
+            self.ui_state.cursor_pos = final_pos;
+            self.ui_state.ideal_cursor_column = final_pos;
+        }
+    }
+
+    /// Move to start of previous big_word (vim B) - can cross field boundaries
+    pub fn move_big_word_prev(&mut self) {
+        use crate::canvas::actions::movement::word::find_prev_big_word_start;
+        let current_text = self.current_text();
+
+        if current_text.is_empty() {
+            // Empty field - try to move to previous field and find last big_word
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                // Check if we actually moved to a different field
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        let last_big_word_start = find_last_big_word_start_in_field(new_text);
+                        self.ui_state.cursor_pos = last_big_word_start;
+                        self.ui_state.ideal_cursor_column = last_big_word_start;
+                    }
+                }
+            }
+            return;
+        }
+
+        let current_pos = self.ui_state.cursor_pos;
+
+        // Special case: if we're at position 0, jump to previous field
+        if current_pos == 0 {
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                // Check if we actually moved to a different field
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        let last_big_word_start = find_last_big_word_start_in_field(new_text);
+                        self.ui_state.cursor_pos = last_big_word_start;
+                        self.ui_state.ideal_cursor_column = last_big_word_start;
+                    }
+                }
+            }
+            return;
+        }
+
+        // Try to find previous big_word in current field
+        let new_pos = find_prev_big_word_start(current_text, current_pos);
+
+        // Check if we actually moved
+        if new_pos < current_pos {
+            // Normal big_word movement within current field - we found a previous big_word
+            self.ui_state.cursor_pos = new_pos;
+            self.ui_state.ideal_cursor_column = new_pos;
+        } else {
+            // We didn't move (probably at start of first big_word), try previous field
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                // Check if we actually moved to a different field
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        let last_big_word_start = find_last_big_word_start_in_field(new_text);
+                        self.ui_state.cursor_pos = last_big_word_start;
+                        self.ui_state.ideal_cursor_column = last_big_word_start;
+                    }
+                }
+            }
+        }
+    }
+
+    /// Move to end of current/next big_word (vim E) - can cross field boundaries
+    pub fn move_big_word_end(&mut self) {
+        use crate::canvas::actions::movement::word::find_big_word_end;
+        let current_text = self.current_text();
+
+        if current_text.is_empty() {
+            // Empty field - try to move to next field (but don't recurse)
+            if self.move_down().is_ok() {
+                let new_text = self.current_text();
+                if !new_text.is_empty() {
+                    // Find first big_word end in new field
+                    let first_big_word_end = find_big_word_end(new_text, 0);
+                    let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+                    let char_len = new_text.chars().count();
+                    let final_pos = if is_edit_mode {
+                        first_big_word_end.min(char_len)
+                    } else {
+                        first_big_word_end.min(char_len.saturating_sub(1))
+                    };
+                    self.ui_state.cursor_pos = final_pos;
+                    self.ui_state.ideal_cursor_column = final_pos;
+                }
+            }
+            return;
+        }
+
+        let current_pos = self.ui_state.cursor_pos;
+        let char_len = current_text.chars().count();
+        let new_pos = find_big_word_end(current_text, current_pos);
+
+        // Check if we didn't move or hit the end of the field
+        if new_pos == current_pos && current_pos + 1 < char_len {
+            // Try next character and find big_word end from there
+            let next_pos = find_big_word_end(current_text, current_pos + 1);
+            if next_pos < char_len {
+                let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+                let final_pos = if is_edit_mode {
+                    next_pos.min(char_len)
+                } else {
+                    next_pos.min(char_len.saturating_sub(1))
+                };
+                self.ui_state.cursor_pos = final_pos;
+                self.ui_state.ideal_cursor_column = final_pos;
+                return;
+            }
+        }
+
+        // If we're at or near the end of the field, try next field (but don't recurse)
+        if new_pos >= char_len.saturating_sub(1) {
+            if self.move_down().is_ok() {
+                // Find first big_word end in new field
+                let new_text = self.current_text();
+                if !new_text.is_empty() {
+                    let first_big_word_end = find_big_word_end(new_text, 0);
+                    let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+                    let new_char_len = new_text.chars().count();
+                    let final_pos = if is_edit_mode {
+                        first_big_word_end.min(new_char_len)
+                    } else {
+                        first_big_word_end.min(new_char_len.saturating_sub(1))
+                    };
+                    self.ui_state.cursor_pos = final_pos;
+                    self.ui_state.ideal_cursor_column = final_pos;
+                }
+            }
+        } else {
+            // Normal big_word end movement within current field
+            let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+            let final_pos = if is_edit_mode {
+                new_pos.min(char_len)
+            } else {
+                new_pos.min(char_len.saturating_sub(1))
+            };
+
+            self.ui_state.cursor_pos = final_pos;
+            self.ui_state.ideal_cursor_column = final_pos;
+        }
+    }
+
+    /// Move to end of previous big_word (vim gE) - can cross field boundaries
+    pub fn move_big_word_end_prev(&mut self) {
+        use crate::canvas::actions::movement::word::{
+            find_prev_big_word_end, find_big_word_end,
+        };
+
+        let current_text = self.current_text();
+
+        if current_text.is_empty() {
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        // Find first big_word end in new field
+                        let last_big_word_end = find_big_word_end(new_text, 0);
+                        self.ui_state.cursor_pos = last_big_word_end;
+                        self.ui_state.ideal_cursor_column = last_big_word_end;
+                    }
+                }
+            }
+            return;
+        }
+
+        let current_pos = self.ui_state.cursor_pos;
+        let new_pos = find_prev_big_word_end(current_text, current_pos);
+
+        // Only try to cross fields if we didn't move at all (stayed at same position)
+        if new_pos == current_pos {
+            let current_field = self.ui_state.current_field;
+            if self.move_up().is_ok() {
+                if self.ui_state.current_field != current_field {
+                    let new_text = self.current_text();
+                    if !new_text.is_empty() {
+                        let last_big_word_end = find_big_word_end(new_text, 0);
+                        self.ui_state.cursor_pos = last_big_word_end;
+                        self.ui_state.ideal_cursor_column = last_big_word_end;
+                    }
+                }
+            }
+        } else {
+            // Normal big_word movement within current field
+            let is_edit_mode = self.ui_state.current_mode == AppMode::Edit;
+            let char_len = current_text.chars().count();
+            let final_pos = if is_edit_mode {
+                new_pos.min(char_len)
+            } else {
+                new_pos.min(char_len.saturating_sub(1))
+            };
+            self.ui_state.cursor_pos = final_pos;
+            self.ui_state.ideal_cursor_column = final_pos;
+        }
+    }
+}
--- a/canvas/src/editor/navigation.rs
+++ b/canvas/src/editor/navigation.rs
@@ -0,0 +1,177 @@
+// src/editor/navigation.rs
+
+use crate::canvas::modes::AppMode;
+use crate::editor::FormEditor;
+use crate::DataProvider;
+
+impl<D: DataProvider> FormEditor<D> {
+    /// Centralized field transition logic (unchanged).
+    pub fn transition_to_field(&mut self, new_field: usize) -> anyhow::Result<()> {
+        let field_count = self.data_provider.field_count();
+        if field_count == 0 {
+            return Ok(());
+        }
+
+        let prev_field = self.ui_state.current_field;
+
+        #[cfg(feature = "computed")]
+        let mut target_field = new_field.min(field_count - 1);
+        #[cfg(not(feature = "computed"))]
+        let target_field = new_field.min(field_count - 1);
+
+        #[cfg(feature = "computed")]
+        {
+            if let Some(computed_state) = &self.ui_state.computed {
+                if computed_state.is_computed_field(target_field) {
+                    if target_field >= prev_field {
+                        for i in (target_field + 1)..field_count {
+                            if !computed_state.is_computed_field(i) {
+                                target_field = i;
+                                break;
+                            }
+                        }
+                    } else {
+                        let mut i = target_field;
+                        loop {
+                            if !computed_state.is_computed_field(i) {
+                                target_field = i;
+                                break;
+                            }
+                            if i == 0 {
+                                break;
+                            }
+                            i -= 1;
+                        }
+                    }
+                }
+            }
+        }
+
+        if target_field == prev_field {
+            return Ok(());
+        }
+
+        #[cfg(feature = "validation")]
+        self.ui_state.validation.clear_last_switch_block();
+
+        #[cfg(feature = "validation")]
+        {
+            let current_text = self.current_text();
+            if !self
+                .ui_state
+                .validation
+                .allows_field_switch(prev_field, current_text)
+            {
+                if let Some(reason) = self
+                    .ui_state
+                    .validation
+                    .field_switch_block_reason(prev_field, current_text)
+                {
+                    self.ui_state
+                        .validation
+                        .set_last_switch_block(reason.clone());
+                    tracing::debug!("Field switch blocked: {}", reason);
+                    return Err(anyhow::anyhow!(
+                        "Cannot switch fields: {}",
+                        reason
+                    ));
+                }
+            }
+        }
+
+        #[cfg(feature = "validation")]
+        {
+            let text =
+                self.data_provider.field_value(prev_field).to_string();
+            let _ = self
+                .ui_state
+                .validation
+                .validate_field_content(prev_field, &text);
+
+            if let Some(cfg) =
+                self.ui_state.validation.get_field_config(prev_field)
+            {
+                if cfg.external_validation_enabled && !text.is_empty() {
+                    self.set_external_validation(
+                        prev_field,
+                        crate::validation::ExternalValidationState::Validating,
+                    );
+
+                    if let Some(cb) =
+                        self.external_validation_callback.as_mut()
+                    {
+                        let final_state = cb(prev_field, &text);
+                        self.set_external_validation(prev_field, final_state);
+                    }
+                }
+            }
+        }
+
+        #[cfg(feature = "computed")]
+        {
+            // Placeholder for recompute hook if needed later
+        }
+
+        self.ui_state.move_to_field(target_field, field_count);
+
+        let current_text = self.current_text();
+        let max_pos = current_text.chars().count();
+        self.ui_state.set_cursor(
+            self.ui_state.ideal_cursor_column,
+            max_pos,
+            self.ui_state.current_mode == AppMode::Edit,
+        );
+
+        // Automatically close suggestions on field switch
+        #[cfg(feature = "suggestions")]
+        {
+            self.close_suggestions();
+        }
+
+        Ok(())
+    }
+
+    /// Move to first line (vim gg)
+    pub fn move_first_line(&mut self) -> anyhow::Result<()> {
+        self.transition_to_field(0)
+    }
+
+    /// Move to last line (vim G)
+    pub fn move_last_line(&mut self) -> anyhow::Result<()> {
+        let last_field =
+            self.data_provider.field_count().saturating_sub(1);
+        self.transition_to_field(last_field)
+    }
+
+    /// Move to previous field (vim k / up)
+    pub fn move_up(&mut self) -> anyhow::Result<()> {
+        let new_field = self.ui_state.current_field.saturating_sub(1);
+        self.transition_to_field(new_field)
+    }
+
+    /// Move to next field (vim j / down)
+    pub fn move_down(&mut self) -> anyhow::Result<()> {
+        let new_field = (self.ui_state.current_field + 1)
+            .min(self.data_provider.field_count().saturating_sub(1));
+        self.transition_to_field(new_field)
+    }
+
+    /// Move to next field cyclic
+    pub fn move_to_next_field(&mut self) -> anyhow::Result<()> {
+        let field_count = self.data_provider.field_count();
+        if field_count == 0 {
+            return Ok(());
+        }
+        let new_field = (self.ui_state.current_field + 1) % field_count;
+        self.transition_to_field(new_field)
+    }
+
+    /// Aliases
+    pub fn prev_field(&mut self) -> anyhow::Result<()> {
+        self.move_up()
+    }
+
+    pub fn next_field(&mut self) -> anyhow::Result<()> {
+        self.move_down()
+    }
+}
--- a/canvas/src/editor/suggestions.rs
+++ b/canvas/src/editor/suggestions.rs
@@ -0,0 +1,166 @@
+// src/editor/suggestions.rs
+
+use crate::editor::FormEditor;
+use crate::{DataProvider, SuggestionItem};
+
+impl<D: DataProvider> FormEditor<D> {
+    /// Compute inline completion for current selection and text
+    fn compute_current_completion(&self) -> Option<String> {
+        let typed = self.current_text();
+        let idx = self.ui_state.suggestions.selected_index?;
+        let sugg = self.suggestions.get(idx)?;
+        if let Some(rest) = sugg.value_to_store.strip_prefix(typed) {
+            if !rest.is_empty() {
+                return Some(rest.to_string());
+            }
+        }
+        None
+    }
+
+    /// Update UI state's completion text from current selection
+    pub fn update_inline_completion(&mut self) {
+        self.ui_state.suggestions.completion_text =
+            self.compute_current_completion();
+    }
+
+    /// Open the suggestions UI for `field_index`
+    pub fn open_suggestions(&mut self, field_index: usize) {
+        self.ui_state.open_suggestions(field_index);
+    }
+
+    /// Close suggestions UI and clear current suggestion results
+    pub fn close_suggestions(&mut self) {
+        self.ui_state.close_suggestions();
+        self.suggestions.clear();
+    }
+
+    /// Handle Escape key in ReadOnly mode (closes suggestions if active)
+    pub fn handle_escape_readonly(&mut self) {
+        if self.ui_state.suggestions.is_active {
+            self.close_suggestions();
+        }
+    }
+
+    // ----------------- Non-blocking suggestions API --------------------
+
+    #[cfg(feature = "suggestions")]
+    pub fn start_suggestions(&mut self, field_index: usize) -> Option<String> {
+        if !self.data_provider.supports_suggestions(field_index) {
+            return None;
+        }
+
+        let query = self.current_text().to_string();
+        self.ui_state.open_suggestions(field_index);
+        self.ui_state.suggestions.is_loading = true;
+        self.ui_state.suggestions.active_query = Some(query.clone());
+        self.suggestions.clear();
+        Some(query)
+    }
+
+    #[cfg(not(feature = "suggestions"))]
+    pub fn start_suggestions(&mut self, _field_index: usize) -> Option<String> {
+        None
+    }
+
+    #[cfg(feature = "suggestions")]
+    pub fn apply_suggestions_result(
+        &mut self,
+        field_index: usize,
+        query: &str,
+        results: Vec<SuggestionItem>,
+    ) -> bool {
+        if self.ui_state.suggestions.active_field != Some(field_index) {
+            return false;
+        }
+        if self.ui_state.suggestions.active_query.as_deref() != Some(query) {
+            return false;
+        }
+
+        self.ui_state.suggestions.is_loading = false;
+        self.suggestions = results;
+
+        if !self.suggestions.is_empty() {
+            self.ui_state.suggestions.selected_index = Some(0);
+            self.update_inline_completion();
+        } else {
+            self.ui_state.suggestions.selected_index = None;
+            self.ui_state.suggestions.completion_text = None;
+        }
+        true
+    }
+
+    #[cfg(not(feature = "suggestions"))]
+    pub fn apply_suggestions_result(
+        &mut self,
+        _field_index: usize,
+        _query: &str,
+        _results: Vec<SuggestionItem>,
+    ) -> bool {
+        false
+    }
+
+    #[cfg(feature = "suggestions")]
+    pub fn pending_suggestions_query(&self) -> Option<(usize, String)> {
+        if self.ui_state.suggestions.is_loading {
+            if let (Some(field), Some(query)) = (
+                self.ui_state.suggestions.active_field,
+                &self.ui_state.suggestions.active_query,
+            ) {
+                return Some((field, query.clone()));
+            }
+        }
+        None
+    }
+
+    #[cfg(not(feature = "suggestions"))]
+    pub fn pending_suggestions_query(&self) -> Option<(usize, String)> {
+        None
+    }
+
+    pub fn cancel_suggestions(&mut self) {
+        self.close_suggestions();
+    }
+
+    pub fn suggestions_next(&mut self) {
+        if !self.ui_state.suggestions.is_active || self.suggestions.is_empty()
+        {
+            return;
+        }
+
+        let current = self.ui_state.suggestions.selected_index.unwrap_or(0);
+        let next = (current + 1) % self.suggestions.len();
+        self.ui_state.suggestions.selected_index = Some(next);
+        self.update_inline_completion();
+    }
+
+    pub fn apply_suggestion(&mut self) -> Option<String> {
+        if let Some(selected_index) = self.ui_state.suggestions.selected_index {
+            if let Some(suggestion) = self.suggestions.get(selected_index).cloned()
+            {
+                let field_index = self.ui_state.current_field;
+
+                self.data_provider.set_field_value(
+                    field_index,
+                    suggestion.value_to_store.clone(),
+                );
+
+                self.ui_state.cursor_pos = suggestion.value_to_store.len();
+                self.ui_state.ideal_cursor_column = self.ui_state.cursor_pos;
+
+                self.close_suggestions();
+                self.suggestions.clear();
+
+                #[cfg(feature = "validation")]
+                {
+                    let _ = self.ui_state.validation.validate_field_content(
+                        field_index,
+                        &suggestion.value_to_store,
+                    );
+                }
+
+                return Some(suggestion.display_text);
+            }
+        }
+        None
+    }
+}
--- a/canvas/src/editor/suggestions_stub.rs
+++ b/canvas/src/editor/suggestions_stub.rs
@@ -0,0 +1,23 @@
+// src/editor/suggestions_stub.rs
+// Crate-private no-op methods so internal calls compile when feature is off.
+
+use crate::editor::FormEditor;
+use crate::DataProvider;
+
+impl<D: DataProvider> FormEditor<D> {
+    pub(crate) fn open_suggestions(&mut self, _field_index: usize) {
+        // no-op
+    }
+
+    pub(crate) fn close_suggestions(&mut self) {
+        // no-op
+    }
+
+    pub(crate) fn handle_escape_readonly(&mut self) {
+        // no-op
+    }
+
+    pub(crate) fn cancel_suggestions(&mut self) {
+        // no-op
+    }
+}
--- a/canvas/src/editor/validation_helpers.rs
+++ b/canvas/src/editor/validation_helpers.rs
@@ -0,0 +1,178 @@
+// src/editor/validation_helpers.rs
+
+use crate::editor::FormEditor;
+use crate::DataProvider;
+
+impl<D: DataProvider> FormEditor<D> {
+    #[cfg(feature = "validation")]
+    pub fn set_validation_enabled(&mut self, enabled: bool) {
+        self.ui_state.validation.set_enabled(enabled);
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn is_validation_enabled(&self) -> bool {
+        self.ui_state.validation.is_enabled()
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn set_field_validation(
+        &mut self,
+        field_index: usize,
+        config: crate::validation::ValidationConfig,
+    ) {
+        self.ui_state
+            .validation
+            .set_field_config(field_index, config);
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn remove_field_validation(&mut self, field_index: usize) {
+        self.ui_state.validation.remove_field_config(field_index);
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn validate_current_field(
+        &mut self,
+    ) -> crate::validation::ValidationResult {
+        let field_index = self.ui_state.current_field;
+        let current_text = self.current_text().to_string();
+        self.ui_state
+            .validation
+            .validate_field_content(field_index, &current_text)
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn validate_field(
+        &mut self,
+        field_index: usize,
+    ) -> Option<crate::validation::ValidationResult> {
+        if field_index < self.data_provider.field_count() {
+            let text =
+                self.data_provider.field_value(field_index).to_string();
+            Some(
+                self.ui_state
+                    .validation
+                    .validate_field_content(field_index, &text),
+            )
+        } else {
+            None
+        }
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn clear_validation_results(&mut self) {
+        self.ui_state.validation.clear_all_results();
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn validation_summary(
+        &self,
+    ) -> crate::validation::ValidationSummary {
+        self.ui_state.validation.summary()
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn can_switch_fields(&self) -> bool {
+        let current_text = self.current_text();
+        self.ui_state.validation.allows_field_switch(
+            self.ui_state.current_field,
+            current_text,
+        )
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn field_switch_block_reason(&self) -> Option<String> {
+        let current_text = self.current_text();
+        self.ui_state.validation.field_switch_block_reason(
+            self.ui_state.current_field,
+            current_text,
+        )
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn last_switch_block(&self) -> Option<&str> {
+        self.ui_state.validation.last_switch_block()
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn current_limits_status_text(&self) -> Option<String> {
+        let idx = self.ui_state.current_field;
+        if let Some(cfg) = self.ui_state.validation.get_field_config(idx) {
+            if let Some(limits) = &cfg.character_limits {
+                return limits.status_text(self.current_text());
+            }
+        }
+        None
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn current_formatter_warning(&self) -> Option<String> {
+        let idx = self.ui_state.current_field;
+        if let Some(cfg) = self.ui_state.validation.get_field_config(idx) {
+            if let Some((_fmt, _mapper, warn)) =
+                cfg.run_custom_formatter(self.current_text())
+            {
+                return warn;
+            }
+        }
+        None
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn external_validation_of(
+        &self,
+        field_index: usize,
+    ) -> crate::validation::ExternalValidationState {
+        self.ui_state
+            .validation
+            .get_external_validation(field_index)
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn clear_all_external_validation(&mut self) {
+        self.ui_state.validation.clear_all_external_validation();
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn clear_external_validation(&mut self, field_index: usize) {
+        self.ui_state
+            .validation
+            .clear_external_validation(field_index);
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn set_external_validation(
+        &mut self,
+        field_index: usize,
+        state: crate::validation::ExternalValidationState,
+    ) {
+        self.ui_state
+            .validation
+            .set_external_validation(field_index, state);
+    }
+
+    #[cfg(feature = "validation")]
+    pub fn set_external_validation_callback<F>(&mut self, callback: F)
+    where
+        F: FnMut(usize, &str) -> crate::validation::ExternalValidationState
+            + Send
+            + Sync
+            + 'static,
+    {
+        self.external_validation_callback = Some(Box::new(callback));
+    }
+
+    #[cfg(feature = "validation")]
+    pub(crate) fn initialize_validation(&mut self) {
+        let field_count = self.data_provider.field_count();
+        for field_index in 0..field_count {
+            if let Some(config) =
+                self.data_provider.validation_config(field_index)
+            {
+                self.ui_state
+                    .validation
+                    .set_field_config(field_index, config);
+            }
+        }
+    }
+}
--- a/canvas/src/lib.rs
+++ b/canvas/src/lib.rs
@@ -1,31 +1,73 @@
 // src/lib.rs

 pub mod canvas;
+pub mod editor;
+pub mod data_provider;

-// Only include autocomplete module if feature is enabled
-#[cfg(feature = "autocomplete")]
-pub mod autocomplete;
+// Only include suggestions module if feature is enabled
+#[cfg(feature = "suggestions")]
+pub mod suggestions;

-// Re-export the main API for easy access
-pub use canvas::actions::{CanvasAction, ActionResult, execute};
-pub use canvas::state::{CanvasState, ActionContext};
-pub use canvas::modes::{AppMode, ModeManager, HighlightState};
+// Only include validation module if feature is enabled
+#[cfg(feature = "validation")]
+pub mod validation;

+// Only include computed module if feature is enabled
+#[cfg(feature = "computed")]
+pub mod computed;
+
+#[cfg(feature = "cursor-style")]
+pub use canvas::CursorManager;
+
+// ===================================================================
+// NEW API: Library-owned state pattern
+// ===================================================================
+
+// Main API exports
+pub use editor::FormEditor;
+pub use data_provider::DataProvider;
+#[cfg(feature = "suggestions")]
+pub use data_provider::{SuggestionsProvider, SuggestionItem};
+
+// UI state (read-only access for users)
+pub use canvas::state::EditorState;
+pub use canvas::modes::AppMode;
+
+// Actions and results (for users who want to handle actions manually)
+pub use canvas::actions::{CanvasAction, ActionResult};
+
+// Validation exports (only when validation feature is enabled)
+#[cfg(feature = "validation")]
+pub use validation::{
+    ValidationConfig, ValidationResult, ValidationError,
+    CharacterLimits, ValidationConfigBuilder, ValidationState,
+    ValidationSummary, PatternFilters, PositionFilter, PositionRange, CharacterFilter, 
+    DisplayMask,  // Simple display mask instead of complex ReservedCharacters
+    // Feature 4: custom formatting exports
+    CustomFormatter, FormattingResult, PositionMapper, DefaultPositionMapper,
+};
+
+// Computed exports (only when computed feature is enabled)
+#[cfg(feature = "computed")]
+pub use computed::{ComputedProvider, ComputedContext, ComputedState};
+
+// Theming and GUI
 #[cfg(feature = "gui")]
-pub use canvas::theme::CanvasTheme;
+pub use canvas::theme::{CanvasTheme, DefaultCanvasTheme};

 #[cfg(feature = "gui")]
 pub use canvas::gui::render_canvas;

-// Re-export autocomplete API if feature is enabled
-#[cfg(feature = "autocomplete")]
-pub use autocomplete::{
-    AutocompleteCanvasState, 
-    AutocompleteState, 
-    SuggestionItem,
-    execute_with_autocomplete,
-    handle_autocomplete_feature_action,
-};
+#[cfg(feature = "gui")]
+pub use canvas::gui::render_canvas_default;

-#[cfg(all(feature = "gui", feature = "autocomplete"))]
-pub use autocomplete::render_autocomplete_dropdown;
+#[cfg(all(feature = "gui", feature = "suggestions"))]
+pub use suggestions::gui::render_suggestions_dropdown;
+
+
+// First-class textarea module and exports
+#[cfg(feature = "textarea")]
+pub mod textarea;
+
+#[cfg(feature = "textarea")]
+pub use textarea::{TextArea, TextAreaProvider, TextAreaState, TextAreaEditor};
--- a/canvas/src/autocomplete/gui.rs
+++ b/canvas/src/autocomplete/gui.rs
@@ -1,39 +1,41 @@
-// src/autocomplete/gui.rs
+// src/suggestions/gui.rs
+//! Suggestions dropdown GUI (not inline autocomplete) updated to work with FormEditor

 #[cfg(feature = "gui")]
 use ratatui::{
    layout::{Alignment, Rect},
    style::{Modifier, Style},
-    widgets::{Block, Borders, List, ListItem, ListState, Paragraph},
+    widgets::{Block, List, ListItem, ListState, Paragraph},  // Removed Borders
    Frame,
 };

-// Use the correct import from our types module
-use crate::autocomplete::types::AutocompleteState;
-
 #[cfg(feature = "gui")]
 use crate::canvas::theme::CanvasTheme;
+use crate::data_provider::{DataProvider, SuggestionItem};
+use crate::editor::FormEditor;

 #[cfg(feature = "gui")]
 use unicode_width::UnicodeWidthStr;

-/// Render autocomplete dropdown - call this AFTER rendering canvas
+/// Render suggestions dropdown for FormEditor - call this AFTER rendering canvas
 #[cfg(feature = "gui")]
-pub fn render_autocomplete_dropdown<T: CanvasTheme, D: Clone + Send + 'static>(
+pub fn render_suggestions_dropdown<T: CanvasTheme, D: DataProvider>(
    f: &mut Frame,
    frame_area: Rect,
    input_rect: Rect,
    theme: &T,
-    autocomplete_state: &AutocompleteState<D>,
+    editor: &FormEditor<D>,
 ) {
-    if !autocomplete_state.is_active {
+    let ui_state = editor.ui_state();
+
+    if !ui_state.is_suggestions_active() {
        return;
    }

-    if autocomplete_state.is_loading {
+    if ui_state.suggestions.is_loading {
        render_loading_indicator(f, frame_area, input_rect, theme);
-    } else if !autocomplete_state.suggestions.is_empty() {
-        render_suggestions_dropdown(f, frame_area, input_rect, theme, autocomplete_state);
+    } else if !editor.suggestions().is_empty() {
+        render_suggestions_dropdown_list(f, frame_area, input_rect, theme, editor.suggestions(), ui_state.suggestions.selected_index);
    }
 }

@@ -69,14 +71,15 @@ fn render_loading_indicator<T: CanvasTheme>(

 /// Show actual suggestions list
 #[cfg(feature = "gui")]
-fn render_suggestions_dropdown<T: CanvasTheme, D: Clone + Send + 'static>(
+fn render_suggestions_dropdown_list<T: CanvasTheme>(
    f: &mut Frame,
    frame_area: Rect,
    input_rect: Rect,
    theme: &T,
-    autocomplete_state: &AutocompleteState<D>,
+    suggestions: &[SuggestionItem],  // Fixed: Removed <String> generic parameter
+    selected_index: Option<usize>,
 ) {
-    let display_texts: Vec<&str> = autocomplete_state.suggestions
+    let display_texts: Vec<&str> = suggestions
        .iter()
        .map(|item| item.display_text.as_str())
        .collect();
@@ -96,19 +99,19 @@ fn render_suggestions_dropdown<T: CanvasTheme, D: Clone + Send + 'static>(
    // List items
    let items = create_suggestion_list_items(
        &display_texts,
-        autocomplete_state.selected_index,
+        selected_index,
        dropdown_dimensions.width,
        theme,
    );

    let list = List::new(items).block(dropdown_block);
    let mut list_state = ListState::default();
-    list_state.select(autocomplete_state.selected_index);
+    list_state.select(selected_index);

    f.render_stateful_widget(list, dropdown_area, &mut list_state);
 }

-/// Calculate dropdown size based on suggestions - updated to match client dimensions
+/// Calculate dropdown size based on suggestions
 #[cfg(feature = "gui")]
 fn calculate_dropdown_dimensions(display_texts: &[&str]) -> DropdownDimensions {
    let max_width = display_texts
@@ -117,9 +120,9 @@ fn calculate_dropdown_dimensions(display_texts: &[&str]) -> DropdownDimensions {
        .max()
        .unwrap_or(0) as u16;

-    let horizontal_padding = 2; // Changed from 4 to 2 to match client
-    let width = (max_width + horizontal_padding).max(10); // Changed from 12 to 10 to match client
-    let height = (display_texts.len() as u16).min(5); // Removed +2 since no borders
+    let horizontal_padding = 2;
+    let width = (max_width + horizontal_padding).max(10);
+    let height = (display_texts.len() as u16).min(5);

    DropdownDimensions { width, height }
 }
@@ -152,7 +155,7 @@ fn calculate_dropdown_position(
    dropdown_area
 }

-/// Create styled list items - updated to match client spacing
+/// Create styled list items
 #[cfg(feature = "gui")]
 fn create_suggestion_list_items<'a, T: CanvasTheme>(
    display_texts: &'a [&'a str],
@@ -160,8 +163,7 @@ fn create_suggestion_list_items<'a, T: CanvasTheme>(
    dropdown_width: u16,
    theme: &T,
 ) -> Vec<ListItem<'a>> {
-    let horizontal_padding = 2; // Changed from 4 to 2 to match client
-    let available_width = dropdown_width; // No border padding needed
+    let available_width = dropdown_width;

    display_texts
        .iter()
--- a/canvas/src/suggestions/mod.rs
+++ b/canvas/src/suggestions/mod.rs
@@ -0,0 +1,12 @@
+// src/suggestions/mod.rs
+
+pub mod state;
+#[cfg(feature = "gui")]
+pub mod gui;
+
+// Re-export the main suggestion types
+pub use state::{SuggestionsProvider, SuggestionItem};
+
+// Re-export GUI functions if available
+#[cfg(feature = "gui")]
+pub use gui::render_suggestions_dropdown;
--- a/canvas/src/suggestions/state.rs
+++ b/canvas/src/suggestions/state.rs
@@ -0,0 +1,5 @@
+// src/suggestions/state.rs
+//! Suggestions provider types (for dropdown suggestions, not real inline autocomplete)
+
+// Re-export the main types from data_provider
+pub use crate::data_provider::{SuggestionsProvider, SuggestionItem};
--- a/canvas/src/textarea/mod.rs
+++ b/canvas/src/textarea/mod.rs
@@ -0,0 +1,14 @@
+// src/textarea/mod.rs
+// Module routing and re-exports only. No logic here.
+
+pub mod provider;
+pub mod state;
+
+#[cfg(feature = "gui")]
+pub mod widget;
+
+pub use provider::TextAreaProvider;
+pub use state::{TextAreaEditor, TextAreaState};
+
+#[cfg(feature = "gui")]
+pub use widget::TextArea;
--- a/canvas/src/textarea/provider.rs
+++ b/canvas/src/textarea/provider.rs
@@ -0,0 +1,134 @@
+// src/textarea/provider.rs
+use crate::DataProvider;
+
+#[derive(Debug, Clone)]
+pub struct TextAreaProvider {
+    lines: Vec<String>,
+    name: String,
+}
+
+impl Default for TextAreaProvider {
+    fn default() -> Self {
+        Self {
+            lines: vec![String::new()],
+            name: "Text".to_string(),
+        }
+    }
+}
+
+impl TextAreaProvider {
+    pub fn from_text<S: Into<String>>(text: S) -> Self {
+        let text = text.into();
+        let mut lines: Vec<String> =
+            text.split('\n').map(|s| s.to_string()).collect();
+        if lines.is_empty() {
+            lines.push(String::new());
+        }
+        Self {
+            lines,
+            name: "Text".to_string(),
+        }
+    }
+
+    pub fn to_text(&self) -> String {
+        self.lines.join("\n")
+    }
+
+    pub fn set_text<S: Into<String>>(&mut self, text: S) {
+        let text = text.into();
+        self.lines = text.split('\n').map(|s| s.to_string()).collect();
+        if self.lines.is_empty() {
+            self.lines.push(String::new());
+        }
+    }
+
+    pub fn line_count(&self) -> usize {
+        self.lines.len()
+    }
+
+    #[inline]
+    fn char_to_byte_index(s: &str, char_idx: usize) -> usize {
+        s.char_indices()
+            .nth(char_idx)
+            .map(|(i, _)| i)
+            .unwrap_or_else(|| s.len())
+    }
+
+    pub fn split_line_at(&mut self, line_idx: usize, at_char: usize) -> usize {
+        if line_idx >= self.lines.len() {
+            return self.lines.len().saturating_sub(1);
+        }
+        let line = &mut self.lines[line_idx];
+        let byte_idx = Self::char_to_byte_index(line, at_char);
+        let right = line[byte_idx..].to_string();
+        line.truncate(byte_idx);
+        let insert_at = line_idx + 1;
+        self.lines.insert(insert_at, right);
+        insert_at
+    }
+
+    pub fn join_with_next(&mut self, line_idx: usize) -> Option<usize> {
+        if line_idx + 1 >= self.lines.len() {
+            return None;
+        }
+        let left_len = self.lines[line_idx].chars().count();
+        let right = self.lines.remove(line_idx + 1);
+        self.lines[line_idx].push_str(&right);
+        Some(left_len)
+    }
+
+    pub fn join_with_prev(
+        &mut self,
+        line_idx: usize,
+    ) -> Option<(usize, usize)> {
+        if line_idx == 0 || line_idx >= self.lines.len() {
+            return None;
+        }
+        let prev_idx = line_idx - 1;
+        let prev_len = self.lines[prev_idx].chars().count();
+        let curr = self.lines.remove(line_idx);
+        self.lines[prev_idx].push_str(&curr);
+        Some((prev_idx, prev_len))
+    }
+
+    pub fn insert_blank_line_after(&mut self, idx: usize) -> usize {
+        let clamped = idx.min(self.lines.len());
+        let insert_at = if clamped >= self.lines.len() {
+            self.lines.len()
+        } else {
+            clamped + 1
+        };
+        if insert_at == self.lines.len() {
+            self.lines.push(String::new());
+        } else {
+            self.lines.insert(insert_at, String::new());
+        }
+        insert_at
+    }
+
+    pub fn insert_blank_line_before(&mut self, idx: usize) -> usize {
+        let insert_at = idx.min(self.lines.len());
+        self.lines.insert(insert_at, String::new());
+        insert_at
+    }
+}
+
+impl DataProvider for TextAreaProvider {
+    fn field_count(&self) -> usize {
+        self.lines.len()
+    }
+
+    fn field_name(&self, _index: usize) -> &str {
+        &self.name
+    }
+
+    fn field_value(&self, index: usize) -> &str {
+        self.lines.get(index).map(|s| s.as_str()).unwrap_or("")
+    }
+
+    fn set_field_value(&mut self, index: usize, value: String) {
+        if index < self.lines.len() {
+            self.lines[index] = value;
+        }
+    }
+}
--- a/canvas/src/textarea/state.rs
+++ b/canvas/src/textarea/state.rs
@@ -0,0 +1,264 @@
+// src/textarea/state.rs
+use std::ops::{Deref, DerefMut};
+
+use anyhow::Result;
+use crossterm::event::{KeyCode, KeyEvent, KeyEventKind, KeyModifiers};
+
+use crate::editor::FormEditor;
+use crate::textarea::provider::TextAreaProvider;
+
+#[cfg(feature = "gui")]
+use ratatui::{layout::Rect, widgets::Block};
+
+#[cfg(feature = "gui")]
+use unicode_width::UnicodeWidthChar;
+
+pub type TextAreaEditor = FormEditor<TextAreaProvider>;
+
+pub struct TextAreaState {
+    pub(crate) editor: TextAreaEditor,
+    pub(crate) scroll_y: u16,
+    pub(crate) wrap: bool,
+    pub(crate) placeholder: Option<String>,
+}
+
+impl Default for TextAreaState {
+    fn default() -> Self {
+        Self {
+            editor: FormEditor::new(TextAreaProvider::default()),
+            scroll_y: 0,
+            wrap: false,
+            placeholder: None,
+        }
+    }
+}
+
+// Expose the entire FormEditor API directly on TextAreaState
+impl Deref for TextAreaState {
+    type Target = TextAreaEditor;
+
+    fn deref(&self) -> &Self::Target {
+        &self.editor
+    }
+}
+
+impl DerefMut for TextAreaState {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.editor
+    }
+}
+
+impl TextAreaState {
+    pub fn from_text<S: Into<String>>(text: S) -> Self {
+        let provider = TextAreaProvider::from_text(text);
+        Self {
+            editor: FormEditor::new(provider),
+            scroll_y: 0,
+            wrap: false,
+            placeholder: None,
+        }
+    }
+
+    pub fn text(&self) -> String {
+        self.editor.data_provider().to_text()
+    }
+
+    pub fn set_text<S: Into<String>>(&mut self, text: S) {
+        self.editor.data_provider_mut().set_text(text);
+        self.editor.ui_state.current_field = 0;
+        self.editor.ui_state.cursor_pos = 0;
+        self.editor.ui_state.ideal_cursor_column = 0;
+    }
+
+    pub fn set_wrap(&mut self, wrap: bool) {
+        self.wrap = wrap;
+    }
+
+    pub fn set_placeholder<S: Into<String>>(&mut self, s: S) {
+        self.placeholder = Some(s.into());
+    }
+
+    // Textarea-specific primitive: split at cursor
+    pub fn insert_newline(&mut self) {
+        let line_idx = self.current_field();
+        let col = self.cursor_position();
+
+        let new_idx = self
+            .editor
+            .data_provider_mut()
+            .split_line_at(line_idx, col);
+
+        let _ = self.transition_to_field(new_idx);
+        self.move_line_start();
+        self.enter_edit_mode();
+    }
+
+    // Textarea-specific primitive: backspace with line join at start-of-line
+    pub fn backspace(&mut self) {
+        let col = self.cursor_position();
+        if col > 0 {
+            let _ = self.delete_backward();
+            return;
+        }
+
+        let line_idx = self.current_field();
+        if line_idx == 0 {
+            return;
+        }
+
+        if let Some((prev_idx, new_col)) = self
+            .editor
+            .data_provider_mut()
+            .join_with_prev(line_idx)
+        {
+            let _ = self.transition_to_field(prev_idx);
+            self.set_cursor_position(new_col);
+            self.enter_edit_mode();
+        }
+    }
+
+    // Textarea-specific primitive: delete or join with next line at EOL
+    pub fn delete_forward_or_join(&mut self) {
+        let line_idx = self.current_field();
+        let line_len = self.current_text().chars().count();
+        let col = self.cursor_position();
+
+        if col < line_len {
+            let _ = self.delete_forward();
+            return;
+        }
+
+        if let Some(new_col) = self
+            .editor
+            .data_provider_mut()
+            .join_with_next(line_idx)
+        {
+            self.set_cursor_position(new_col);
+            self.enter_edit_mode();
+        }
+    }
+
+    // Override for multiline: insert new blank line below and enter insert mode.
+    pub fn open_line_below(&mut self) -> Result<()> {
+        let line_idx = self.current_field();
+        let new_idx = self
+            .editor
+            .data_provider_mut()
+            .insert_blank_line_after(line_idx);
+
+        self.transition_to_field(new_idx)?;
+        self.move_line_start();
+        self.enter_edit_mode();
+        Ok(())
+    }
+
+    // Override for multiline: insert new blank line above and enter insert mode.
+    pub fn open_line_above(&mut self) -> Result<()> {
+        let line_idx = self.current_field();
+        let new_idx = self
+            .editor
+            .data_provider_mut()
+            .insert_blank_line_before(line_idx);
+
+        self.transition_to_field(new_idx)?;
+        self.move_line_start();
+        self.enter_edit_mode();
+        Ok(())
+    }
+
+    // Drive from KeyEvent; you can still call all FormEditor methods directly
+    pub fn input(&mut self, key: KeyEvent) {
+        if key.kind != KeyEventKind::Press {
+            return;
+        }
+
+        match (key.code, key.modifiers) {
+            (KeyCode::Enter, _) => self.insert_newline(),
+            (KeyCode::Backspace, _) => self.backspace(),
+            (KeyCode::Delete, _) => self.delete_forward_or_join(),
+
+            (KeyCode::Left, _) => {
+                let _ = self.move_left();
+            }
+            (KeyCode::Right, _) => {
+                let _ = self.move_right();
+            }
+            (KeyCode::Up, _) => {
+                let _ = self.move_up();
+            }
+            (KeyCode::Down, _) => {
+                let _ = self.move_down();
+            }
+
+            (KeyCode::Home, _)
+            | (KeyCode::Char('a'), KeyModifiers::CONTROL) => {
+                self.move_line_start();
+            }
+            (KeyCode::End, _)
+            | (KeyCode::Char('e'), KeyModifiers::CONTROL) => {
+                self.move_line_end();
+            }
+
+            // Optional: word motions
+            (KeyCode::Char('b'), KeyModifiers::ALT) => self.move_word_prev(),
+            (KeyCode::Char('f'), KeyModifiers::ALT) => self.move_word_next(),
+            (KeyCode::Char('e'), KeyModifiers::ALT) => self.move_word_end(),
+
+            // Printable characters
+            (KeyCode::Char(c), m) if m.is_empty() => {
+                self.enter_edit_mode();
+                let _ = self.insert_char(c);
+            }
+
+            // Simple Tab policy
+            (KeyCode::Tab, _) => {
+                self.enter_edit_mode();
+                for _ in 0..4 {
+                    let _ = self.insert_char(' ');
+                }
+            }
+
+            _ => {}
+        }
+    }
+
+    // Cursor helpers for GUI
+    #[cfg(feature = "gui")]
+    pub fn cursor(&self, area: Rect, block: Option<&Block<'_>>) -> (u16, u16) {
+        let inner = if let Some(b) = block { b.inner(area) } else { area };
+        let line_idx = self.current_field() as u16;
+        let y = inner.y + line_idx.saturating_sub(self.scroll_y);
+
+        let current_line = self.current_text();
+        let col = self.display_cursor_position();
+
+        let mut x_off: u16 = 0;
+        for (i, ch) in current_line.chars().enumerate() {
+            if i >= col {
+                break;
+            }
+            x_off = x_off
+                .saturating_add(UnicodeWidthChar::width(ch).unwrap_or(0) as u16);
+        }
+        let x = inner.x.saturating_add(x_off);
+        (x, y)
+    }
+
+    #[cfg(feature = "gui")]
+    pub(crate) fn ensure_visible(
+        &mut self,
+        area: Rect,
+        block: Option<&Block<'_>>,
+    ) {
+        let inner = if let Some(b) = block { b.inner(area) } else { area };
+        if inner.height == 0 {
+            return;
+        }
+        let line_idx = self.current_field() as u16;
+        if line_idx < self.scroll_y {
+            self.scroll_y = line_idx;
+        } else if line_idx >= self.scroll_y + inner.height {
+            self.scroll_y = line_idx.saturating_sub(inner.height - 1);
+        }
+    }
+}
--- a/canvas/src/textarea/widget.rs
+++ b/canvas/src/textarea/widget.rs
@@ -0,0 +1,106 @@
+// src/textarea/widget.rs
+#[cfg(feature = "gui")]
+use ratatui::{
+    buffer::Buffer,
+    layout::{Alignment, Rect},
+    style::Style,
+    text::{Line, Span},
+    widgets::{
+        Block, BorderType, Borders, Paragraph, StatefulWidget, Widget, Wrap,
+    },
+};
+
+#[cfg(feature = "gui")]
+use crate::data_provider::DataProvider; // bring trait into scope
+
+#[cfg(feature = "gui")]
+use crate::textarea::state::TextAreaState;
+
+#[cfg(feature = "gui")]
+#[derive(Debug, Clone)]
+pub struct TextArea<'a> {
+    pub(crate) block: Option<Block<'a>>,
+    pub(crate) style: Style,
+    pub(crate) border_type: BorderType,
+}
+
+#[cfg(feature = "gui")]
+impl<'a> Default for TextArea<'a> {
+    fn default() -> Self {
+        Self {
+            block: Some(
+                Block::default()
+                    .borders(Borders::ALL)
+                    .border_type(BorderType::Rounded),
+            ),
+            style: Style::default(),
+            border_type: BorderType::Rounded,
+        }
+    }
+}
+
+#[cfg(feature = "gui")]
+impl<'a> TextArea<'a> {
+    pub fn block(mut self, block: Block<'a>) -> Self {
+        self.block = Some(block);
+        self
+    }
+
+    pub fn style(mut self, style: Style) -> Self {
+        self.style = style;
+        self
+    }
+
+    pub fn border_type(mut self, ty: BorderType) -> Self {
+        self.border_type = ty;
+        if let Some(b) = &mut self.block {
+            *b = b.clone().border_type(ty);
+        }
+        self
+    }
+}
+
+#[cfg(feature = "gui")]
+impl<'a> StatefulWidget for TextArea<'a> {
+    type State = TextAreaState;
+
+    fn render(self, area: Rect, buf: &mut Buffer, state: &mut Self::State) {
+        state.ensure_visible(area, self.block.as_ref());
+
+        let inner = if let Some(b) = &self.block {
+            b.clone().render(area, buf);
+            b.inner(area)
+        } else {
+            area
+        };
+
+        let total = state.editor.data_provider().line_count();
+        let start = state.scroll_y as usize;
+        let end = start
+            .saturating_add(inner.height as usize)
+            .min(total);
+
+        let mut display_lines: Vec<Line> = Vec::with_capacity(end - start);
+
+        if start >= end {
+            if let Some(ph) = &state.placeholder {
+                display_lines.push(Line::from(Span::raw(ph.clone())));
+            }
+        } else {
+            for i in start..end {
+                let s = state.editor.data_provider().field_value(i);
+                display_lines.push(Line::from(Span::raw(s.to_string())));
+            }
+        }
+
+        let mut p = Paragraph::new(display_lines)
+            .alignment(Alignment::Left)
+            .style(self.style);
+
+        if state.wrap {
+            p = p.wrap(Wrap { trim: false });
+        }
+
+        p.render(inner, buf);
+    }
+}
--- a/canvas/src/validation/config.rs
+++ b/canvas/src/validation/config.rs
@@ -0,0 +1,447 @@
+// src/validation/config.rs
+//! Validation configuration types and builders
+
+use crate::validation::{CharacterLimits, PatternFilters, DisplayMask};
+#[cfg(feature = "validation")]
+use crate::validation::{CustomFormatter, FormattingResult, PositionMapper};
+use std::sync::Arc;
+
+/// Main validation configuration for a field
+#[derive(Clone, Default)]
+pub struct ValidationConfig {
+    /// Character limit configuration
+    pub character_limits: Option<CharacterLimits>,
+
+    /// Pattern filtering configuration
+    pub pattern_filters: Option<PatternFilters>,
+
+    /// User-defined display mask for visual formatting
+    pub display_mask: Option<DisplayMask>,
+
+    /// Optional: user-provided custom formatter (feature 4)
+    #[cfg(feature = "validation")]
+    pub custom_formatter: Option<Arc<dyn CustomFormatter + Send + Sync>>,
+
+    /// Enable external validation indicator UI (feature 5)
+    pub external_validation_enabled: bool,
+
+    /// Future: External validation
+    pub external_validation: Option<()>, // Placeholder for future implementation
+}
+
+/// Manual Debug to avoid requiring Debug on dyn CustomFormatter
+impl std::fmt::Debug for ValidationConfig {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let mut ds = f.debug_struct("ValidationConfig");
+        ds.field("character_limits", &self.character_limits)
+          .field("pattern_filters", &self.pattern_filters)
+          .field("display_mask", &self.display_mask)
+          // Do not print the formatter itself to avoid requiring Debug
+          .field(
+              "custom_formatter",
+              &{
+                  #[cfg(feature = "validation")]
+                  {
+                      if self.custom_formatter.is_some() { &"Some(<CustomFormatter>)" } else { &"None" }
+                  }
+                  #[cfg(not(feature = "validation"))]
+                  {
+                      &"N/A"
+                  }
+              },
+          )
+          .field("external_validation_enabled", &self.external_validation_enabled)
+          .field("external_validation", &self.external_validation)
+          .finish()
+    }
+}
+
+// ✅ FIXED: Move function from struct definition to impl block
+impl ValidationConfig {
+    /// If a custom formatter is configured, run it and return the formatted text,
+    /// the position mapper and an optional warning message.
+    ///
+    /// Returns None when no custom formatter is configured.
+    #[cfg(feature = "validation")]
+    pub fn run_custom_formatter(
+        &self,
+        raw: &str,
+    ) -> Option<(String, Arc<dyn PositionMapper>, Option<String>)> {
+        let formatter = self.custom_formatter.as_ref()?;
+        match formatter.format(raw) {
+            FormattingResult::Success { formatted, mapper } => {
+                Some((formatted, mapper, None))
+            }
+            FormattingResult::Warning { formatted, message, mapper } => {
+                Some((formatted, mapper, Some(message)))
+            }
+            FormattingResult::Error { .. } => None, // Fall back to raw display
+        }
+    }
+
+    /// Create a new empty validation configuration
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Create a configuration with just character limits
+    pub fn with_max_length(max_length: usize) -> Self {
+        ValidationConfigBuilder::new()
+            .with_max_length(max_length)
+            .build()
+    }
+
+    /// Create a configuration with pattern filters
+    pub fn with_patterns(patterns: PatternFilters) -> Self {
+        ValidationConfigBuilder::new()
+            .with_pattern_filters(patterns)
+            .build()
+    }
+
+    /// Create a configuration with user-defined display mask
+    ///
+    /// # Examples
+    /// ```
+    /// use canvas::{ValidationConfig, DisplayMask};
+    ///
+    /// let phone_mask = DisplayMask::new("(###) ###-####", '#');
+    /// let config = ValidationConfig::with_mask(phone_mask);
+    /// ```
+    pub fn with_mask(mask: DisplayMask) -> Self {
+        ValidationConfigBuilder::new()
+            .with_display_mask(mask)
+            .build()
+    }
+
+    /// Validate a character insertion at a specific position (raw text space).
+    ///
+    /// Note: Display masks are visual-only and do not participate in validation.
+    /// Editor logic is responsible for skipping mask separator positions; here we
+    /// only validate the raw insertion against limits and patterns.
+    pub fn validate_char_insertion(
+        &self,
+        current_text: &str,
+        position: usize,
+        character: char,
+    ) -> ValidationResult {
+        // Character limits validation
+        if let Some(ref limits) = self.character_limits {
+            // ✅ FIXED: Explicit return type annotation
+            if let Some(result) = limits.validate_insertion(current_text, position, character) {
+                if !result.is_acceptable() {
+                    return result;
+                }
+            }
+        }
+
+        // Pattern filters validation
+        if let Some(ref patterns) = self.pattern_filters {
+            // ✅ FIXED: Explicit error handling
+            if let Err(message) = patterns.validate_char_at_position(position, character) {
+                return ValidationResult::error(message);
+            }
+        }
+
+        // Future: Add other validation types here
+
+        ValidationResult::Valid
+    }
+
+    /// Validate the current text content (raw text space)
+    pub fn validate_content(&self, text: &str) -> ValidationResult {
+        // Character limits validation
+        if let Some(ref limits) = self.character_limits {
+            // ✅ FIXED: Explicit return type annotation
+            if let Some(result) = limits.validate_content(text) {
+                if !result.is_acceptable() {
+                    return result;
+                }
+            }
+        }
+
+        // Pattern filters validation
+        if let Some(ref patterns) = self.pattern_filters {
+            // ✅ FIXED: Explicit error handling
+            if let Err(message) = patterns.validate_text(text) {
+                return ValidationResult::error(message);
+            }
+        }
+
+        // Future: Add other validation types here
+
+        ValidationResult::Valid
+    }
+
+    /// Check if any validation rules are configured
+    pub fn has_validation(&self) -> bool {
+        self.character_limits.is_some()
+            || self.pattern_filters.is_some()
+            || self.display_mask.is_some()
+            || {
+                #[cfg(feature = "validation")]
+                { self.custom_formatter.is_some() }
+                #[cfg(not(feature = "validation"))]
+                { false }
+            }
+    }
+
+    pub fn allows_field_switch(&self, text: &str) -> bool {
+        // Character limits validation
+        if let Some(ref limits) = self.character_limits {
+            // ✅ FIXED: Direct boolean return
+            if !limits.allows_field_switch(text) {
+                return false;
+            }
+        }
+
+        // Future: Add other validation types here
+
+        true
+    }
+
+    /// Get reason why field switching is blocked (if any)
+    pub fn field_switch_block_reason(&self, text: &str) -> Option<String> {
+        // Character limits validation
+        if let Some(ref limits) = self.character_limits {
+            // ✅ FIXED: Direct option return
+            if let Some(reason) = limits.field_switch_block_reason(text) {
+                return Some(reason);
+            }
+        }
+
+        // Future: Add other validation types here
+
+        None
+    }
+}
+
+/// Builder for creating validation configurations
+#[derive(Debug, Default)]
+pub struct ValidationConfigBuilder {
+    config: ValidationConfig,
+}
+
+impl ValidationConfigBuilder {
+    /// Create a new validation config builder
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Set character limits for the field
+    pub fn with_character_limits(mut self, limits: CharacterLimits) -> Self {
+        self.config.character_limits = Some(limits);
+        self
+    }
+
+    /// Set pattern filters for the field
+    pub fn with_pattern_filters(mut self, filters: PatternFilters) -> Self {
+        self.config.pattern_filters = Some(filters);
+        self
+    }
+
+    /// Set user-defined display mask for visual formatting
+    ///
+    /// # Examples
+    /// ```
+    /// use canvas::{ValidationConfigBuilder, DisplayMask};
+    ///
+    /// // Phone number with dynamic formatting
+    /// let phone_mask = DisplayMask::new("(###) ###-####", '#');
+    /// let config = ValidationConfigBuilder::new()
+    ///     .with_display_mask(phone_mask)
+    ///     .build();
+    ///
+    /// // Date with template formatting
+    /// let date_mask = DisplayMask::new("##/##/####", '#')
+    ///     .with_template('_');
+    /// let config = ValidationConfigBuilder::new()
+    ///     .with_display_mask(date_mask)
+    ///     .build();
+    ///
+    /// // Custom business format
+    /// let employee_id = DisplayMask::new("EMP-####-##", '#')
+    ///     .with_template('•');
+    /// let config = ValidationConfigBuilder::new()
+    ///     .with_display_mask(employee_id)
+    ///     .with_max_length(6)  // Only store the 6 digits
+    ///     .build();
+    /// ```
+    pub fn with_display_mask(mut self, mask: DisplayMask) -> Self {
+        self.config.display_mask = Some(mask);
+        self
+    }
+
+    /// Set optional custom formatter (feature 4)
+    #[cfg(feature = "validation")]
+    pub fn with_custom_formatter<F>(mut self, formatter: Arc<F>) -> Self
+    where
+        F: CustomFormatter + Send + Sync + 'static,
+    {
+        self.config.custom_formatter = Some(formatter);
+        // When custom formatter is present, it takes precedence over display mask.
+        self.config.display_mask = None;
+        self
+    }
+
+    /// Set maximum number of characters (convenience method)
+    pub fn with_max_length(mut self, max_length: usize) -> Self {
+        self.config.character_limits = Some(CharacterLimits::new(max_length));
+        self
+    }
+
+    /// Enable or disable external validation indicator UI (feature 5)
+    pub fn with_external_validation_enabled(mut self, enabled: bool) -> Self {
+        self.config.external_validation_enabled = enabled;
+        self
+    }
+
+    /// Build the final validation configuration
+    pub fn build(self) -> ValidationConfig {
+        self.config
+    }
+}
+
+/// Result of a validation operation
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum ValidationResult {
+    /// Validation passed
+    Valid,
+
+    /// Validation failed with warning (input still accepted)
+    Warning { message: String },
+
+    /// Validation failed with error (input rejected)
+    Error { message: String },
+}
+
+impl ValidationResult {
+    /// Check if the validation result allows the input
+    pub fn is_acceptable(&self) -> bool {
+        matches!(self, ValidationResult::Valid | ValidationResult::Warning { .. })
+    }
+
+    /// Check if the validation result is an error
+    pub fn is_error(&self) -> bool {
+        matches!(self, ValidationResult::Error { .. })
+    }
+
+    /// Get the message if there is one
+    pub fn message(&self) -> Option<&str> {
+        match self {
+            ValidationResult::Valid => None,
+            ValidationResult::Warning { message } => Some(message),
+            ValidationResult::Error { message } => Some(message),
+        }
+    }
+
+    /// Create a warning result
+    pub fn warning(message: impl Into<String>) -> Self {
+        ValidationResult::Warning { message: message.into() }
+    }
+
+    /// Create an error result
+    pub fn error(message: impl Into<String>) -> Self {
+        ValidationResult::Error { message: message.into() }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_config_with_user_defined_mask() {
+        // User creates their own phone mask
+        let phone_mask = DisplayMask::new("(###) ###-####", '#');
+        let config = ValidationConfig::with_mask(phone_mask);
+
+        // has_validation should be true because mask is configured
+        assert!(config.has_validation());
+
+        // Display mask is visual only; validation still focuses on raw content
+        let result = config.validate_char_insertion("123", 3, '4');
+        assert!(result.is_acceptable());
+
+        // Content validation unaffected by mask
+        let result = config.validate_content("1234567890");
+        assert!(result.is_acceptable());
+    }
+
+    #[test]
+    fn test_validation_config_builder() {
+        let config = ValidationConfigBuilder::new()
+            .with_max_length(10)
+            .build();
+
+        assert!(config.character_limits.is_some());
+        assert_eq!(config.character_limits.unwrap().max_length(), Some(10));
+    }
+
+    #[test]
+    fn test_config_builder_with_user_mask() {
+        // User defines custom format
+        let custom_mask = DisplayMask::new("##-##-##", '#').with_template('_');
+        let config = ValidationConfigBuilder::new()
+            .with_display_mask(custom_mask)
+            .with_max_length(6)
+            .build();
+
+        assert!(config.has_validation());
+        assert!(config.character_limits.is_some());
+        assert!(config.display_mask.is_some());
+    }
+
+    #[test]
+    fn test_validation_result() {
+        let valid = ValidationResult::Valid;
+        assert!(valid.is_acceptable());
+        assert!(!valid.is_error());
+        assert_eq!(valid.message(), None);
+
+        let warning = ValidationResult::warning("Too long");
+        assert!(warning.is_acceptable());
+        assert!(!warning.is_error());
+        assert_eq!(warning.message(), Some("Too long"));
+
+        let error = ValidationResult::error("Invalid");
+        assert!(!error.is_acceptable());
+        assert!(error.is_error());
+        assert_eq!(error.message(), Some("Invalid"));
+    }
+
+    #[test]
+    fn test_config_with_max_length() {
+        let config = ValidationConfig::with_max_length(5);
+        assert!(config.has_validation());
+
+        // Test valid insertion
+        let result = config.validate_char_insertion("test", 4, 'x');
+        assert!(result.is_acceptable());
+
+        // Test invalid insertion (would exceed limit)
+        let result = config.validate_char_insertion("tests", 5, 'x');
+        assert!(!result.is_acceptable());
+    }
+
+    #[test]
+    fn test_config_with_patterns() {
+        use crate::validation::{PatternFilters, PositionFilter, PositionRange, CharacterFilter};
+
+        let patterns = PatternFilters::new()
+            .add_filter(PositionFilter::new(
+                PositionRange::Range(0, 1),
+                CharacterFilter::Alphabetic,
+            ));
+
+        let config = ValidationConfig::with_patterns(patterns);
+        assert!(config.has_validation());
+
+        // Test valid pattern insertion
+        let result = config.validate_char_insertion("", 0, 'A');
+        assert!(result.is_acceptable());
+
+        // Test invalid pattern insertion
+        let result = config.validate_char_insertion("", 0, '1');
+        assert!(!result.is_acceptable());
+    }
+}
--- a/canvas/src/validation/formatting.rs
+++ b/canvas/src/validation/formatting.rs
@@ -0,0 +1,217 @@
+/* canvas/src/validation/formatting.rs
+   Add new formatting module with CustomFormatter, PositionMapper, DefaultPositionMapper, and FormattingResult
+*/
+use std::sync::Arc;
+
+/// Bidirectional mapping between raw input positions and formatted display positions.
+///
+/// The library uses this to keep cursor/selection behavior intuitive when the UI
+/// shows a formatted transformation (e.g., "01001" -> "010 01") while the editor
+/// still stores raw text.
+pub trait PositionMapper: Send + Sync {
+    /// Map a raw cursor position to a formatted cursor position.
+    ///
+    /// raw_pos is an index into the raw text (0..=raw.len() in char positions).
+    /// Implementations should return a position within 0..=formatted.len() (in char positions).
+    fn raw_to_formatted(&self, raw: &str, formatted: &str, raw_pos: usize) -> usize;
+
+    /// Map a formatted cursor position to a raw cursor position.
+    ///
+    /// formatted_pos is an index into the formatted text (0..=formatted.len()).
+    /// Implementations should return a position within 0..=raw.len() (in char positions).
+    fn formatted_to_raw(&self, raw: &str, formatted: &str, formatted_pos: usize) -> usize;
+}
+
+/// A reasonable default mapper that works for "insert separators" style formatting,
+/// such as grouping digits or adding dashes/spaces.
+///
+/// Heuristic:
+/// - Treat letters and digits (is_alphanumeric) in the formatted string as user-entered characters
+///   corresponding to raw characters, in order.
+/// - Treat any non-alphanumeric characters as purely visual separators.
+/// - Raw positions are mapped by counting alphanumeric characters in the formatted string.
+/// - If the formatted contains fewer alphanumeric characters than the raw (shouldn't happen
+///   for plain grouping), we cap at the end of the formatted string.
+#[derive(Clone, Default)]
+pub struct DefaultPositionMapper;
+
+impl PositionMapper for DefaultPositionMapper {
+    fn raw_to_formatted(&self, raw: &str, formatted: &str, raw_pos: usize) -> usize {
+        // Convert to char indices for correctness in presence of UTF-8
+        let raw_len = raw.chars().count();
+        let clamped_raw_pos = raw_pos.min(raw_len);
+
+        // Count alphanumerics in formatted, find the index where we've seen `clamped_raw_pos` of them.
+        let mut seen_user_chars = 0usize;
+        for (idx, ch) in formatted.char_indices() {
+            if ch.is_alphanumeric() {
+                if seen_user_chars == clamped_raw_pos {
+                    // Cursor is positioned before this user character in the formatted view
+                    return idx;
+                }
+                seen_user_chars += 1;
+            }
+        }
+
+        // If we consumed all alphanumeric chars and still haven't reached clamped_raw_pos,
+        // place cursor at the end of the formatted string.
+        formatted.len()
+    }
+
+    fn formatted_to_raw(&self, raw: &str, formatted: &str, formatted_pos: usize) -> usize {
+        let clamped_fmt_pos = formatted_pos.min(formatted.len());
+
+        // Count alphanumerics in formatted up to formatted_pos.
+        let mut seen_user_chars = 0usize;
+        for (idx, ch) in formatted.char_indices() {
+            if idx >= clamped_fmt_pos {
+                break;
+            }
+            if ch.is_alphanumeric() {
+                seen_user_chars += 1;
+            }
+        }
+
+        // Map to raw position by clamping to raw char count
+        let raw_len = raw.chars().count();
+        seen_user_chars.min(raw_len)
+    }
+}
+
+/// Result of invoking a custom formatter on the raw input.
+///
+/// Success variants carry the formatted string and a position mapper to translate
+/// between raw and formatted cursor positions. If you don't provide a custom mapper,
+/// the library will fall back to DefaultPositionMapper.
+pub enum FormattingResult {
+    /// Successfully produced a formatted display value and a position mapper.
+    Success {
+        formatted: String,
+        /// Mapper to convert cursor positions between raw and formatted representations.
+        mapper: Arc<dyn PositionMapper>,
+    },
+    /// Successfully produced a formatted value, but with a non-fatal warning message
+    /// that can be shown in the UI (e.g., "incomplete value").
+    Warning {
+        formatted: String,
+        message: String,
+        mapper: Arc<dyn PositionMapper>,
+    },
+    /// Failed to produce a formatted display. The library will typically fall back to raw.
+    Error {
+        message: String,
+    },
+}
+
+impl FormattingResult {
+    /// Convenience to create a success result using the default mapper.
+    pub fn success(formatted: impl Into<String>) -> Self {
+        FormattingResult::Success {
+            formatted: formatted.into(),
+            mapper: Arc::new(DefaultPositionMapper::default()),
+        }
+    }
+
+    /// Convenience to create a warning result using the default mapper.
+    pub fn warning(formatted: impl Into<String>, message: impl Into<String>) -> Self {
+        FormattingResult::Warning {
+            formatted: formatted.into(),
+            message: message.into(),
+            mapper: Arc::new(DefaultPositionMapper::default()),
+        }
+    }
+
+    /// Convenience to create a success result with a custom mapper.
+    pub fn success_with_mapper(
+        formatted: impl Into<String>,
+        mapper: Arc<dyn PositionMapper>,
+    ) -> Self {
+        FormattingResult::Success {
+            formatted: formatted.into(),
+            mapper,
+        }
+    }
+
+    /// Convenience to create a warning result with a custom mapper.
+    pub fn warning_with_mapper(
+        formatted: impl Into<String>,
+        message: impl Into<String>,
+        mapper: Arc<dyn PositionMapper>,
+    ) -> Self {
+        FormattingResult::Warning {
+            formatted: formatted.into(),
+            message: message.into(),
+            mapper,
+        }
+    }
+
+    /// Convenience to create an error result.
+    pub fn error(message: impl Into<String>) -> Self {
+        FormattingResult::Error {
+            message: message.into(),
+        }
+    }
+}
+
+/// A user-implemented formatter that turns raw input into a formatted display string,
+/// optionally providing a custom cursor position mapper.
+///
+/// Notes:
+/// - The library will keep raw input authoritative for editing and validation.
+/// - The formatted value is only used for display.
+/// - If formatting fails, return Error; the library will show the raw value.
+/// - For common grouping (spaces/dashes), you can return Success/Warning and rely
+///   on DefaultPositionMapper, or provide your own mapper for advanced cases
+///   (reordering, compression, locale-specific rules, etc.).
+pub trait CustomFormatter: Send + Sync {
+    fn format(&self, raw: &str) -> FormattingResult;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    struct GroupEvery3;
+    impl CustomFormatter for GroupEvery3 {
+        fn format(&self, raw: &str) -> FormattingResult {
+            let mut out = String::new();
+            for (i, ch) in raw.chars().enumerate() {
+                if i > 0 && i % 3 == 0 {
+                    out.push(' ');
+                }
+                out.push(ch);
+            }
+            FormattingResult::success(out)
+        }
+    }
+
+    #[test]
+    fn default_mapper_roundtrip_basic() {
+        let mapper = DefaultPositionMapper::default();
+        let raw = "01001";
+        let formatted = "010 01";
+
+        // raw_to_formatted monotonicity and bounds
+        for rp in 0..=raw.chars().count() {
+            let fp = mapper.raw_to_formatted(raw, formatted, rp);
+            assert!(fp <= formatted.len());
+        }
+
+        // formatted_to_raw bounds
+        for fp in 0..=formatted.len() {
+            let rp = mapper.formatted_to_raw(raw, formatted, fp);
+            assert!(rp <= raw.chars().count());
+        }
+    }
+
+    #[test]
+    fn formatter_groups_every_3() {
+        let f = GroupEvery3;
+        match f.format("1234567") {
+            FormattingResult::Success { formatted, .. } => {
+                assert_eq!(formatted, "123 456 7");
+            }
+            _ => panic!("expected success"),
+        }
+    }
+}
--- a/canvas/src/validation/limits.rs
+++ b/canvas/src/validation/limits.rs
@@ -0,0 +1,441 @@
+// src/validation/limits.rs
+//! Character limits validation implementation
+
+use crate::validation::ValidationResult;
+use serde::{Deserialize, Serialize};
+use unicode_width::UnicodeWidthStr;
+
+/// Character limits configuration for a field
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct CharacterLimits {
+    /// Maximum number of characters allowed (None = unlimited)
+    max_length: Option<usize>,
+    
+    /// Minimum number of characters required (None = no minimum)
+    min_length: Option<usize>,
+    
+    /// Warning threshold (warn when approaching max limit)
+    warning_threshold: Option<usize>,
+    
+    /// Count mode: characters vs display width
+    count_mode: CountMode,
+}
+
+/// How to count characters for limit checking
+#[derive(Debug, Clone, Copy, Serialize, Deserialize)]
+pub enum CountMode {
+    /// Count actual characters (default)
+    Characters,
+    
+    /// Count display width (useful for CJK characters)
+    DisplayWidth,
+    
+    /// Count bytes (rarely used, but available)
+    Bytes,
+}
+
+impl Default for CountMode {
+    fn default() -> Self {
+        CountMode::Characters
+    }
+}
+
+/// Result of a character limit check
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum LimitCheckResult {
+    /// Within limits
+    Ok,
+    
+    /// Approaching limit (warning)
+    Warning { current: usize, max: usize },
+    
+    /// At or exceeding limit (error)
+    Exceeded { current: usize, max: usize },
+    
+    /// Below minimum length
+    TooShort { current: usize, min: usize },
+}
+
+impl CharacterLimits {
+    /// Create new character limits with just max length
+    pub fn new(max_length: usize) -> Self {
+        Self {
+            max_length: Some(max_length),
+            min_length: None,
+            warning_threshold: None,
+            count_mode: CountMode::default(),
+        }
+    }
+    
+    /// Create new character limits with min and max
+    pub fn new_range(min_length: usize, max_length: usize) -> Self {
+        Self {
+            max_length: Some(max_length),
+            min_length: Some(min_length),
+            warning_threshold: None,
+            count_mode: CountMode::default(),
+        }
+    }
+    
+    /// Set warning threshold (when to show warning before hitting limit)
+    pub fn with_warning_threshold(mut self, threshold: usize) -> Self {
+        self.warning_threshold = Some(threshold);
+        self
+    }
+    
+    /// Set count mode (characters vs display width vs bytes)
+    pub fn with_count_mode(mut self, mode: CountMode) -> Self {
+        self.count_mode = mode;
+        self
+    }
+    
+    /// Get maximum length
+    pub fn max_length(&self) -> Option<usize> {
+        self.max_length
+    }
+    
+    /// Get minimum length
+    pub fn min_length(&self) -> Option<usize> {
+        self.min_length
+    }
+    
+    /// Get warning threshold
+    pub fn warning_threshold(&self) -> Option<usize> {
+        self.warning_threshold
+    }
+    
+    /// Get count mode
+    pub fn count_mode(&self) -> CountMode {
+        self.count_mode
+    }
+    
+    /// Count characters/width/bytes according to the configured mode
+    fn count(&self, text: &str) -> usize {
+        match self.count_mode {
+            CountMode::Characters => text.chars().count(),
+            CountMode::DisplayWidth => text.width(),
+            CountMode::Bytes => text.len(),
+        }
+    }
+    
+    /// Check if inserting a character would exceed limits
+    pub fn validate_insertion(
+        &self,
+        current_text: &str,
+        position: usize,
+        character: char,
+    ) -> Option<ValidationResult> {
+        // FIX: Actually simulate the insertion at the specified position
+        // This makes the `position` parameter essential to the logic
+        
+        // 1. Create the new string by inserting the character at the correct position
+        let mut new_text = String::with_capacity(current_text.len() + character.len_utf8());
+        let mut chars = current_text.chars();
+
+        // Append characters from the original string that come before the insertion point
+        // We clamp the position to be safe
+        let clamped_pos = position.min(current_text.chars().count());
+        for _ in 0..clamped_pos {
+            if let Some(ch) = chars.next() {
+                new_text.push(ch);
+            }
+        }
+
+        // Insert the new character
+        new_text.push(character);
+
+        // Append the rest of the original string
+        for ch in chars {
+            new_text.push(ch);
+        }
+
+        // 2. Now perform all validation on the *actual* resulting text
+        let new_count = self.count(&new_text);
+        let current_count = self.count(current_text);
+
+        // Check max length
+        if let Some(max) = self.max_length {
+            if new_count > max {
+                return Some(ValidationResult::error(format!(
+                    "Character limit exceeded: {}/{}",
+                    new_count,
+                    max
+                )));
+            }
+
+            // Check warning threshold
+            if let Some(warning_threshold) = self.warning_threshold {
+                if new_count >= warning_threshold && current_count < warning_threshold {
+                    return Some(ValidationResult::warning(format!(
+                        "Approaching character limit: {}/{}",
+                        new_count,
+                        max
+                    )));
+                }
+            }
+        }
+
+        None // No validation issues
+    }
+    
+    /// Validate the current content
+    pub fn validate_content(&self, text: &str) -> Option<ValidationResult> {
+        let count = self.count(text);
+        
+        // Check minimum length
+        if let Some(min) = self.min_length {
+            if count < min {
+                return Some(ValidationResult::warning(format!(
+                    "Minimum length not met: {}/{}", 
+                    count, 
+                    min
+                )));
+            }
+        }
+        
+        // Check maximum length
+        if let Some(max) = self.max_length {
+            if count > max {
+                return Some(ValidationResult::error(format!(
+                    "Character limit exceeded: {}/{}", 
+                    count, 
+                    max
+                )));
+            }
+            
+            // Check warning threshold
+            if let Some(warning_threshold) = self.warning_threshold {
+                if count >= warning_threshold {
+                    return Some(ValidationResult::warning(format!(
+                        "Approaching character limit: {}/{}", 
+                        count, 
+                        max
+                    )));
+                }
+            }
+        }
+        
+        None // No validation issues
+    }
+    
+    /// Get the current status of the text against limits
+    pub fn check_limits(&self, text: &str) -> LimitCheckResult {
+        let count = self.count(text);
+        
+        // Check max length first
+        if let Some(max) = self.max_length {
+            if count > max {
+                return LimitCheckResult::Exceeded { current: count, max };
+            }
+            
+            // Check warning threshold
+            if let Some(warning_threshold) = self.warning_threshold {
+                if count >= warning_threshold {
+                    return LimitCheckResult::Warning { current: count, max };
+                }
+            }
+        }
+        
+        // Check min length
+        if let Some(min) = self.min_length {
+            if count < min {
+                return LimitCheckResult::TooShort { current: count, min };
+            }
+        }
+        
+        LimitCheckResult::Ok
+    }
+    
+    /// Get a human-readable status string
+    pub fn status_text(&self, text: &str) -> Option<String> {
+        match self.check_limits(text) {
+            LimitCheckResult::Ok => {
+                // Show current/max if we have a max limit
+                if let Some(max) = self.max_length {
+                    Some(format!("{}/{}", self.count(text), max))
+                } else {
+                    None
+                }
+            },
+            LimitCheckResult::Warning { current, max } => {
+                Some(format!("{}/{} (approaching limit)", current, max))
+            },
+            LimitCheckResult::Exceeded { current, max } => {
+                Some(format!("{}/{} (exceeded)", current, max))
+            },
+            LimitCheckResult::TooShort { current, min } => {
+                Some(format!("{}/{} minimum", current, min))
+            },
+        }
+    }
+    pub fn allows_field_switch(&self, text: &str) -> bool {
+        if let Some(min) = self.min_length {
+            let count = self.count(text);
+            // Allow switching if field is empty OR meets minimum requirement
+            count == 0 || count >= min
+        } else {
+            true // No minimum requirement, always allow switching
+        }
+    }
+    
+    /// Get reason why field switching is not allowed (if any)
+    pub fn field_switch_block_reason(&self, text: &str) -> Option<String> {
+        if let Some(min) = self.min_length {
+            let count = self.count(text);
+            if count > 0 && count < min {
+                return Some(format!(
+                    "Field must be empty or have at least {} characters (currently: {})",
+                    min, count
+                ));
+            }
+        }
+        None
+    }
+}
+
+impl Default for CharacterLimits {
+    fn default() -> Self {
+        Self {
+            max_length: Some(30), // Default 30 character limit as specified
+            min_length: None,
+            warning_threshold: None,
+            count_mode: CountMode::default(),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_character_limits_creation() {
+        let limits = CharacterLimits::new(10);
+        assert_eq!(limits.max_length(), Some(10));
+        assert_eq!(limits.min_length(), None);
+        
+        let range_limits = CharacterLimits::new_range(5, 15);
+        assert_eq!(range_limits.min_length(), Some(5));
+        assert_eq!(range_limits.max_length(), Some(15));
+    }
+    
+    #[test]
+    fn test_default_limits() {
+        let limits = CharacterLimits::default();
+        assert_eq!(limits.max_length(), Some(30));
+    }
+    
+    #[test]
+    fn test_character_counting() {
+        let limits = CharacterLimits::new(5);
+        
+        // Test character mode (default)
+        assert_eq!(limits.count("hello"), 5);
+        assert_eq!(limits.count("héllo"), 5); // Accented character counts as 1
+        
+        // Test display width mode
+        let limits = limits.with_count_mode(CountMode::DisplayWidth);
+        assert_eq!(limits.count("hello"), 5);
+        
+        // Test bytes mode
+        let limits = limits.with_count_mode(CountMode::Bytes);
+        assert_eq!(limits.count("hello"), 5);
+        assert_eq!(limits.count("héllo"), 6); // é takes 2 bytes in UTF-8
+    }
+    
+    #[test]
+    fn test_insertion_validation() {
+        let limits = CharacterLimits::new(5);
+        
+        // Valid insertion
+        let result = limits.validate_insertion("test", 4, 'x');
+        assert!(result.is_none()); // No validation issues
+        
+        // Invalid insertion (would exceed limit)
+        let result = limits.validate_insertion("tests", 5, 'x');
+        assert!(result.is_some());
+        assert!(!result.unwrap().is_acceptable());
+    }
+    
+    #[test]
+    fn test_content_validation() {
+        let limits = CharacterLimits::new_range(3, 10);
+        
+        // Too short
+        let result = limits.validate_content("hi");
+        assert!(result.is_some());
+        assert!(result.unwrap().is_acceptable()); // Warning, not error
+        
+        // Just right
+        let result = limits.validate_content("hello");
+        assert!(result.is_none());
+        
+        // Too long
+        let result = limits.validate_content("hello world!");
+        assert!(result.is_some());
+        assert!(!result.unwrap().is_acceptable()); // Error
+    }
+    
+    #[test]
+    fn test_warning_threshold() {
+        let limits = CharacterLimits::new(10).with_warning_threshold(8);
+        
+        // Below warning threshold
+        let result = limits.validate_insertion("1234567", 7, 'x');
+        assert!(result.is_none());
+        
+        // At warning threshold
+        let result = limits.validate_insertion("1234567", 7, 'x');
+        assert!(result.is_none()); // This brings us to 8 chars
+        
+        let result = limits.validate_insertion("12345678", 8, 'x');
+        assert!(result.is_some());
+        assert!(result.unwrap().is_acceptable()); // Warning, not error
+    }
+    
+    #[test]
+    fn test_status_text() {
+        let limits = CharacterLimits::new(10);
+        
+        assert_eq!(limits.status_text("hello"), Some("5/10".to_string()));
+        
+        let limits = limits.with_warning_threshold(8);
+        assert_eq!(limits.status_text("12345678"), Some("8/10 (approaching limit)".to_string()));
+        assert_eq!(limits.status_text("1234567890x"), Some("11/10 (exceeded)".to_string()));
+    }
+    
+    #[test]
+    fn test_field_switch_blocking() {
+        let limits = CharacterLimits::new_range(3, 10);
+        
+        // Empty field: should allow switching
+        assert!(limits.allows_field_switch(""));
+        assert!(limits.field_switch_block_reason("").is_none());
+        
+        // Field with content below minimum: should block switching
+        assert!(!limits.allows_field_switch("hi"));
+        assert!(limits.field_switch_block_reason("hi").is_some());
+        assert!(limits.field_switch_block_reason("hi").unwrap().contains("at least 3 characters"));
+        
+        // Field meeting minimum: should allow switching
+        assert!(limits.allows_field_switch("hello"));
+        assert!(limits.field_switch_block_reason("hello").is_none());
+        
+        // Field exceeding maximum: should still allow switching (validation shows error but doesn't block)
+        assert!(limits.allows_field_switch("this is way too long"));
+        assert!(limits.field_switch_block_reason("this is way too long").is_none());
+    }
+    
+    #[test]
+    fn test_field_switch_no_minimum() {
+        let limits = CharacterLimits::new(10); // Only max, no minimum
+        
+        // Should always allow switching when there's no minimum
+        assert!(limits.allows_field_switch(""));
+        assert!(limits.allows_field_switch("a"));
+        assert!(limits.allows_field_switch("hello"));
+        
+        assert!(limits.field_switch_block_reason("").is_none());
+        assert!(limits.field_switch_block_reason("a").is_none());
+    }
+}
--- a/canvas/src/validation/mask.rs
+++ b/canvas/src/validation/mask.rs
@@ -0,0 +1,333 @@
+// src/validation/mask.rs
+//! Pure display mask system - user-defined patterns only
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum MaskDisplayMode {
+    /// Only show separators as user types
+    /// Example: "" → "", "123" → "123", "12345" → "(123) 45"
+    Dynamic,
+    
+    /// Show full template with placeholders from start
+    /// Example: "" → "(___) ___-____", "123" → "(123) ___-____"
+    Template { 
+        /// Character to use as placeholder for empty input positions
+        placeholder: char 
+    },
+}
+
+impl Default for MaskDisplayMode {
+    fn default() -> Self {
+        MaskDisplayMode::Dynamic
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct DisplayMask {
+    /// Mask pattern like "##-##-####" where # = input position, others are visual separators
+    pattern: String,
+    /// Character used to represent input positions (usually '#')
+    input_char: char,
+    /// How to display the mask (dynamic vs template)
+    display_mode: MaskDisplayMode,
+}
+
+impl DisplayMask {
+    /// Create a new display mask with dynamic mode (current behavior)
+    /// 
+    /// # Arguments
+    /// * `pattern` - The mask pattern (e.g., "##-##-####", "(###) ###-####")  
+    /// * `input_char` - Character representing input positions (usually '#')
+    /// 
+    /// # Examples
+    /// ```
+    /// // Phone number format
+    /// let phone_mask = DisplayMask::new("(###) ###-####", '#');
+    /// 
+    /// // Date format  
+    /// let date_mask = DisplayMask::new("##/##/####", '#');
+    /// 
+    /// // Custom business format
+    /// let employee_id = DisplayMask::new("EMP-####-##", '#');
+    /// ```
+    pub fn new(pattern: impl Into<String>, input_char: char) -> Self {
+        Self {
+            pattern: pattern.into(),
+            input_char,
+            display_mode: MaskDisplayMode::Dynamic,
+        }
+    }
+
+    /// Set the display mode for this mask
+    /// 
+    /// # Examples
+    /// ```
+    /// let dynamic_mask = DisplayMask::new("##-##", '#')
+    ///     .with_mode(MaskDisplayMode::Dynamic);
+    ///     
+    /// let template_mask = DisplayMask::new("##-##", '#')
+    ///     .with_mode(MaskDisplayMode::Template { placeholder: '_' });
+    /// ```
+    pub fn with_mode(mut self, mode: MaskDisplayMode) -> Self {
+        self.display_mode = mode;
+        self
+    }
+
+    /// Set template mode with custom placeholder
+    /// 
+    /// # Examples
+    /// ```
+    /// let phone_template = DisplayMask::new("(###) ###-####", '#')
+    ///     .with_template('_');  // Shows "(___) ___-____" when empty
+    ///     
+    /// let date_dots = DisplayMask::new("##/##/####", '#')
+    ///     .with_template('•');  // Shows "••/••/••••" when empty
+    /// ```
+    pub fn with_template(self, placeholder: char) -> Self {
+        self.with_mode(MaskDisplayMode::Template { placeholder })
+    }
+
+    /// Apply mask to raw input, showing visual separators and handling display mode
+    pub fn apply_to_display(&self, raw_input: &str) -> String {
+        match &self.display_mode {
+            MaskDisplayMode::Dynamic => self.apply_dynamic(raw_input),
+            MaskDisplayMode::Template { placeholder } => self.apply_template(raw_input, *placeholder),
+        }
+    }
+
+    /// Dynamic mode - only show separators as user types
+    fn apply_dynamic(&self, raw_input: &str) -> String {
+        let mut result = String::new();
+        let mut raw_chars = raw_input.chars();
+
+        for pattern_char in self.pattern.chars() {
+            if pattern_char == self.input_char {
+                // Input position - take from raw input
+                if let Some(input_char) = raw_chars.next() {
+                    result.push(input_char);
+                } else {
+                    // No more input - stop here in dynamic mode
+                    break;
+                }
+            } else {
+                // Visual separator - always show
+                result.push(pattern_char);
+            }
+        }
+
+        // Append any remaining raw characters that don't fit the pattern
+        for remaining_char in raw_chars {
+            result.push(remaining_char);
+        }
+
+        result
+    }
+
+    /// Template mode - show full pattern with placeholders
+    fn apply_template(&self, raw_input: &str, placeholder: char) -> String {
+        let mut result = String::new();
+        let mut raw_chars = raw_input.chars().peekable();
+
+        for pattern_char in self.pattern.chars() {
+            if pattern_char == self.input_char {
+                // Input position - take from raw input or use placeholder
+                if let Some(input_char) = raw_chars.next() {
+                    result.push(input_char);
+                } else {
+                    // No more input - use placeholder to show template
+                    result.push(placeholder);
+                }
+            } else {
+                // Visual separator - always show in template mode
+                result.push(pattern_char);
+            }
+        }
+
+        // In template mode, we don't append extra characters beyond the pattern
+        // This keeps the template consistent
+        result
+    }
+
+    /// Check if a display position should accept cursor/input
+    pub fn is_input_position(&self, display_position: usize) -> bool {
+        self.pattern.chars()
+            .nth(display_position)
+            .map(|c| c == self.input_char)
+            .unwrap_or(true) // Beyond pattern = accept input
+    }
+
+    /// Map display position to raw position
+    pub fn display_pos_to_raw_pos(&self, display_pos: usize) -> usize {
+        let mut raw_pos = 0;
+
+        for (i, pattern_char) in self.pattern.chars().enumerate() {
+            if i >= display_pos {
+                break;
+            }
+            if pattern_char == self.input_char {
+                raw_pos += 1;
+            }
+        }
+
+        raw_pos
+    }
+
+    /// Map raw position to display position
+    pub fn raw_pos_to_display_pos(&self, raw_pos: usize) -> usize {
+        let mut input_positions_seen = 0;
+
+        for (display_pos, pattern_char) in self.pattern.chars().enumerate() {
+            if pattern_char == self.input_char {
+                if input_positions_seen == raw_pos {
+                    return display_pos;
+                }
+                input_positions_seen += 1;
+            }
+        }
+
+        // Beyond pattern, return position after pattern
+        self.pattern.len() + (raw_pos - input_positions_seen)
+    }
+
+    /// Find next input position at or after the given display position
+    pub fn next_input_position(&self, display_pos: usize) -> usize {
+        for (i, pattern_char) in self.pattern.chars().enumerate().skip(display_pos) {
+            if pattern_char == self.input_char {
+                return i;
+            }
+        }
+        // Beyond pattern = all positions are input positions
+        display_pos.max(self.pattern.len())
+    }
+
+    /// Find previous input position at or before the given display position
+    pub fn prev_input_position(&self, display_pos: usize) -> Option<usize> {
+        // Collect pattern chars with indices first, then search backwards
+        let pattern_chars: Vec<(usize, char)> = self.pattern.chars().enumerate().collect();
+        
+        // Search backwards from display_pos
+        for &(i, pattern_char) in pattern_chars.iter().rev() {
+            if i <= display_pos && pattern_char == self.input_char {
+                return Some(i);
+            }
+        }
+        None
+    }
+
+    /// Get the display mode
+    pub fn display_mode(&self) -> &MaskDisplayMode {
+        &self.display_mode
+    }
+
+    /// Check if this mask uses template mode
+    pub fn is_template_mode(&self) -> bool {
+        matches!(self.display_mode, MaskDisplayMode::Template { .. })
+    }
+
+    /// Get the pattern string
+    pub fn pattern(&self) -> &str {
+        &self.pattern
+    }
+
+    /// Get the position of the first input character in the pattern
+    pub fn first_input_position(&self) -> usize {
+        for (pos, ch) in self.pattern.chars().enumerate() {
+            if ch == self.input_char {
+                return pos;
+            }
+        }
+        0
+    }
+}
+
+impl Default for DisplayMask {
+    fn default() -> Self {
+        Self::new("", '#')
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_user_defined_phone_mask() {
+        // User creates their own phone mask
+        let dynamic = DisplayMask::new("(###) ###-####", '#');
+        let template = DisplayMask::new("(###) ###-####", '#').with_template('_');
+        
+        // Dynamic mode
+        assert_eq!(dynamic.apply_to_display(""), "");
+        assert_eq!(dynamic.apply_to_display("1234567890"), "(123) 456-7890");
+        
+        // Template mode
+        assert_eq!(template.apply_to_display(""), "(___) ___-____");
+        assert_eq!(template.apply_to_display("123"), "(123) ___-____");
+    }
+
+    #[test]
+    fn test_user_defined_date_mask() {
+        // User creates their own date formats
+        let us_date = DisplayMask::new("##/##/####", '#');
+        let eu_date = DisplayMask::new("##.##.####", '#');
+        let iso_date = DisplayMask::new("####-##-##", '#');
+        
+        assert_eq!(us_date.apply_to_display("12252024"), "12/25/2024");
+        assert_eq!(eu_date.apply_to_display("25122024"), "25.12.2024");
+        assert_eq!(iso_date.apply_to_display("20241225"), "2024-12-25");
+    }
+
+    #[test]
+    fn test_user_defined_business_formats() {
+        // User creates custom business formats
+        let employee_id = DisplayMask::new("EMP-####-##", '#');
+        let product_code = DisplayMask::new("###-###-###", '#');
+        let invoice = DisplayMask::new("INV####/##", '#');
+        
+        assert_eq!(employee_id.apply_to_display("123456"), "EMP-1234-56");
+        assert_eq!(product_code.apply_to_display("123456789"), "123-456-789");
+        assert_eq!(invoice.apply_to_display("123456"), "INV1234/56");
+    }
+
+    #[test]
+    fn test_custom_input_characters() {
+        // User can define their own input character
+        let mask_with_x = DisplayMask::new("XXX-XX-XXXX", 'X');
+        let mask_with_hash = DisplayMask::new("###-##-####", '#');
+        let mask_with_n = DisplayMask::new("NNN-NN-NNNN", 'N');
+        
+        assert_eq!(mask_with_x.apply_to_display("123456789"), "123-45-6789");
+        assert_eq!(mask_with_hash.apply_to_display("123456789"), "123-45-6789");
+        assert_eq!(mask_with_n.apply_to_display("123456789"), "123-45-6789");
+    }
+
+    #[test]
+    fn test_custom_placeholders() {
+        // User can define custom placeholder characters
+        let underscores = DisplayMask::new("##-##", '#').with_template('_');
+        let dots = DisplayMask::new("##-##", '#').with_template('•');
+        let dashes = DisplayMask::new("##-##", '#').with_template('-');
+        
+        assert_eq!(underscores.apply_to_display(""), "__-__");
+        assert_eq!(dots.apply_to_display(""), "••-••");
+        assert_eq!(dashes.apply_to_display(""), "---");  // Note: dashes blend with separator
+    }
+
+    #[test]
+    fn test_position_mapping_user_patterns() {
+        let custom = DisplayMask::new("ABC-###-XYZ", '#');
+        
+        // Position mapping should work correctly with any pattern
+        assert_eq!(custom.raw_pos_to_display_pos(0), 4); // First # at position 4
+        assert_eq!(custom.raw_pos_to_display_pos(1), 5); // Second # at position 5
+        assert_eq!(custom.raw_pos_to_display_pos(2), 6); // Third # at position 6
+        
+        assert_eq!(custom.display_pos_to_raw_pos(4), 0); // Position 4 -> first input
+        assert_eq!(custom.display_pos_to_raw_pos(5), 1); // Position 5 -> second input
+        assert_eq!(custom.display_pos_to_raw_pos(6), 2); // Position 6 -> third input
+        
+        assert!(!custom.is_input_position(0)); // A
+        assert!(!custom.is_input_position(3)); // -
+        assert!(custom.is_input_position(4));  // #
+        assert!(!custom.is_input_position(8)); // Y
+    }
+}
--- a/canvas/src/validation/mod.rs
+++ b/canvas/src/validation/mod.rs
@@ -0,0 +1,40 @@
+// src/validation/mod.rs
+
+// Core validation modules
+pub mod config;
+pub mod limits;
+pub mod state;
+pub mod patterns;
+pub mod mask;  // Simple display mask instead of complex reserved chars
+pub mod formatting; // Custom formatter and position mapping (feature 4)
+
+// Re-export main types
+pub use config::{ValidationConfig, ValidationResult, ValidationConfigBuilder};
+pub use limits::{CharacterLimits, LimitCheckResult};
+pub use state::{ValidationState, ValidationSummary};
+pub use patterns::{PatternFilters, PositionFilter, PositionRange, CharacterFilter};
+pub use mask::DisplayMask;  // Simple mask instead of ReservedCharacters
+pub use formatting::{CustomFormatter, FormattingResult, PositionMapper, DefaultPositionMapper};
+
+/// External validation UI state (Feature 5)
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum ExternalValidationState {
+    NotValidated,
+    Validating,
+    Valid(Option<String>),
+    Invalid { message: String, suggestion: Option<String> },
+    Warning { message: String },
+}
+
+/// Validation error types
+#[derive(Debug, Clone, thiserror::Error)]
+pub enum ValidationError {
+    #[error("Character limit exceeded: {message}")]
+    LimitExceeded { message: String },
+    
+    #[error("Pattern validation failed: {message}")]
+    PatternFailed { message: String },
+    
+    #[error("Custom validation failed: {message}")]
+    CustomFailed { message: String },
+}
--- a/canvas/src/validation/patterns.rs
+++ b/canvas/src/validation/patterns.rs
@@ -0,0 +1,326 @@
+// src/validation/patterns.rs
+//! Position-based pattern filtering for validation
+
+use serde::{Deserialize, Serialize};
+use std::sync::Arc;
+
+/// A filter that applies to specific character positions in a field
+#[derive(Debug, Clone)]
+pub struct PositionFilter {
+    /// Which positions this filter applies to
+    pub positions: PositionRange,
+    /// What type of character filter to apply
+    pub filter: CharacterFilter,
+}
+
+/// Defines which character positions a filter applies to
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum PositionRange {
+    /// Single position (e.g., position 3 only)
+    Single(usize),
+    /// Range of positions (e.g., positions 0-2, inclusive)
+    Range(usize, usize),
+    /// From position onwards (e.g., position 4 and beyond)
+    From(usize),
+    /// Multiple specific positions (e.g., positions 0, 2, 5)
+    Multiple(Vec<usize>),
+}
+
+/// Types of character filters that can be applied
+pub enum CharacterFilter {
+    /// Allow only alphabetic characters (a-z, A-Z)
+    Alphabetic,
+    /// Allow only numeric characters (0-9)
+    Numeric,
+    /// Allow alphanumeric characters (a-z, A-Z, 0-9)
+    Alphanumeric,
+    /// Allow only exact character match
+    Exact(char),
+    /// Allow any character from the provided set
+    OneOf(Vec<char>),
+    /// Custom user-defined filter function
+    Custom(Arc<dyn Fn(char) -> bool + Send + Sync>),
+}
+
+// Manual implementations for Debug and Clone
+impl std::fmt::Debug for CharacterFilter {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            CharacterFilter::Alphabetic => write!(f, "Alphabetic"),
+            CharacterFilter::Numeric => write!(f, "Numeric"),
+            CharacterFilter::Alphanumeric => write!(f, "Alphanumeric"),
+            CharacterFilter::Exact(ch) => write!(f, "Exact('{}')", ch),
+            CharacterFilter::OneOf(chars) => write!(f, "OneOf({:?})", chars),
+            CharacterFilter::Custom(_) => write!(f, "Custom(<function>)"),
+        }
+    }
+}
+
+impl Clone for CharacterFilter {
+    fn clone(&self) -> Self {
+        match self {
+            CharacterFilter::Alphabetic => CharacterFilter::Alphabetic,
+            CharacterFilter::Numeric => CharacterFilter::Numeric,
+            CharacterFilter::Alphanumeric => CharacterFilter::Alphanumeric,
+            CharacterFilter::Exact(ch) => CharacterFilter::Exact(*ch),
+            CharacterFilter::OneOf(chars) => CharacterFilter::OneOf(chars.clone()),
+            CharacterFilter::Custom(func) => CharacterFilter::Custom(Arc::clone(func)),
+        }
+    }
+}
+
+impl PositionRange {
+    /// Check if a position is included in this range
+    pub fn contains(&self, position: usize) -> bool {
+        match self {
+            PositionRange::Single(pos) => position == *pos,
+            PositionRange::Range(start, end) => position >= *start && position <= *end,
+            PositionRange::From(start) => position >= *start,
+            PositionRange::Multiple(positions) => positions.contains(&position),
+        }
+    }
+
+    /// Get all positions up to a given length that this range covers
+    pub fn positions_up_to(&self, max_length: usize) -> Vec<usize> {
+        match self {
+            PositionRange::Single(pos) => {
+                if *pos < max_length { vec![*pos] } else { vec![] }
+            },
+            PositionRange::Range(start, end) => {
+                let actual_end = (*end).min(max_length.saturating_sub(1));
+                if *start <= actual_end {
+                    (*start..=actual_end).collect()
+                } else {
+                    vec![]
+                }
+            },
+            PositionRange::From(start) => {
+                if *start < max_length {
+                    (*start..max_length).collect()
+                } else {
+                    vec![]
+                }
+            },
+            PositionRange::Multiple(positions) => {
+                positions.iter()
+                    .filter(|&&pos| pos < max_length)
+                    .copied()
+                    .collect()
+            },
+        }
+    }
+}
+
+impl CharacterFilter {
+    /// Test if a character passes this filter
+    pub fn accepts(&self, ch: char) -> bool {
+        match self {
+            CharacterFilter::Alphabetic => ch.is_alphabetic(),
+            CharacterFilter::Numeric => ch.is_numeric(),
+            CharacterFilter::Alphanumeric => ch.is_alphanumeric(),
+            CharacterFilter::Exact(expected) => ch == *expected,
+            CharacterFilter::OneOf(chars) => chars.contains(&ch),
+            CharacterFilter::Custom(func) => func(ch),
+        }
+    }
+
+    /// Get a human-readable description of this filter
+    pub fn description(&self) -> String {
+        match self {
+            CharacterFilter::Alphabetic => "alphabetic characters (a-z, A-Z)".to_string(),
+            CharacterFilter::Numeric => "numeric characters (0-9)".to_string(),
+            CharacterFilter::Alphanumeric => "alphanumeric characters (a-z, A-Z, 0-9)".to_string(),
+            CharacterFilter::Exact(ch) => format!("exactly '{}'", ch),
+            CharacterFilter::OneOf(chars) => {
+                let char_list: String = chars.iter().collect();
+                format!("one of: {}", char_list)
+            },
+            CharacterFilter::Custom(_) => "custom filter".to_string(),
+        }
+    }
+}
+
+impl PositionFilter {
+    /// Create a new position filter
+    pub fn new(positions: PositionRange, filter: CharacterFilter) -> Self {
+        Self { positions, filter }
+    }
+
+    /// Validate a character at a specific position
+    pub fn validate_position(&self, position: usize, character: char) -> bool {
+        if self.positions.contains(position) {
+            self.filter.accepts(character)
+        } else {
+            true // Position not covered by this filter, allow any character
+        }
+    }
+
+    /// Get error message for invalid character at position
+    pub fn error_message(&self, position: usize, character: char) -> Option<String> {
+        if self.positions.contains(position) && !self.filter.accepts(character) {
+            Some(format!(
+                "Position {} requires {} but got '{}'",
+                position,
+                self.filter.description(),
+                character
+            ))
+        } else {
+            None
+        }
+    }
+}
+
+/// A collection of position filters for a field
+#[derive(Debug, Clone, Default)]
+pub struct PatternFilters {
+    filters: Vec<PositionFilter>,
+}
+
+impl PatternFilters {
+    /// Create empty pattern filters
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Add a position filter
+    pub fn add_filter(mut self, filter: PositionFilter) -> Self {
+        self.filters.push(filter);
+        self
+    }
+
+    /// Add multiple filters
+    pub fn add_filters(mut self, filters: Vec<PositionFilter>) -> Self {
+        self.filters.extend(filters);
+        self
+    }
+
+    /// Validate a character at a specific position against all applicable filters
+    pub fn validate_char_at_position(&self, position: usize, character: char) -> Result<(), String> {
+        for filter in &self.filters {
+            if let Some(error) = filter.error_message(position, character) {
+                return Err(error);
+            }
+        }
+        Ok(())
+    }
+
+    /// Validate entire text against all filters
+    pub fn validate_text(&self, text: &str) -> Result<(), String> {
+        for (position, character) in text.char_indices() {
+            if let Err(error) = self.validate_char_at_position(position, character) {
+                return Err(error);
+            }
+        }
+        Ok(())
+    }
+
+    /// Check if any filters are configured
+    pub fn has_filters(&self) -> bool {
+        !self.filters.is_empty()
+    }
+
+    /// Get all configured filters
+    pub fn filters(&self) -> &[PositionFilter] {
+        &self.filters
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_position_range_contains() {
+        assert!(PositionRange::Single(3).contains(3));
+        assert!(!PositionRange::Single(3).contains(2));
+
+        assert!(PositionRange::Range(1, 4).contains(3));
+        assert!(!PositionRange::Range(1, 4).contains(5));
+
+        assert!(PositionRange::From(2).contains(5));
+        assert!(!PositionRange::From(2).contains(1));
+
+        assert!(PositionRange::Multiple(vec![0, 2, 5]).contains(2));
+        assert!(!PositionRange::Multiple(vec![0, 2, 5]).contains(3));
+    }
+
+    #[test]
+    fn test_position_range_positions_up_to() {
+        assert_eq!(PositionRange::Single(3).positions_up_to(5), vec![3]);
+        assert_eq!(PositionRange::Single(5).positions_up_to(3), vec![]);
+
+        assert_eq!(PositionRange::Range(1, 3).positions_up_to(5), vec![1, 2, 3]);
+        assert_eq!(PositionRange::Range(1, 5).positions_up_to(3), vec![1, 2]);
+
+        assert_eq!(PositionRange::From(2).positions_up_to(5), vec![2, 3, 4]);
+
+        assert_eq!(PositionRange::Multiple(vec![0, 2, 5]).positions_up_to(4), vec![0, 2]);
+    }
+
+    #[test]
+    fn test_character_filter_accepts() {
+        assert!(CharacterFilter::Alphabetic.accepts('a'));
+        assert!(CharacterFilter::Alphabetic.accepts('Z'));
+        assert!(!CharacterFilter::Alphabetic.accepts('1'));
+
+        assert!(CharacterFilter::Numeric.accepts('5'));
+        assert!(!CharacterFilter::Numeric.accepts('a'));
+
+        assert!(CharacterFilter::Alphanumeric.accepts('a'));
+        assert!(CharacterFilter::Alphanumeric.accepts('5'));
+        assert!(!CharacterFilter::Alphanumeric.accepts('-'));
+
+        assert!(CharacterFilter::Exact('x').accepts('x'));
+        assert!(!CharacterFilter::Exact('x').accepts('y'));
+
+        assert!(CharacterFilter::OneOf(vec!['a', 'b', 'c']).accepts('b'));
+        assert!(!CharacterFilter::OneOf(vec!['a', 'b', 'c']).accepts('d'));
+    }
+
+    #[test]
+    fn test_position_filter_validation() {
+        let filter = PositionFilter::new(
+            PositionRange::Range(0, 1),
+            CharacterFilter::Alphabetic,
+        );
+
+        assert!(filter.validate_position(0, 'A'));
+        assert!(filter.validate_position(1, 'b'));
+        assert!(!filter.validate_position(0, '1'));
+        assert!(filter.validate_position(2, '1')); // Position 2 not covered, allow anything
+    }
+
+    #[test]
+    fn test_pattern_filters_validation() {
+        let patterns = PatternFilters::new()
+            .add_filter(PositionFilter::new(
+                PositionRange::Range(0, 1),
+                CharacterFilter::Alphabetic,
+            ))
+            .add_filter(PositionFilter::new(
+                PositionRange::Range(2, 4),
+                CharacterFilter::Numeric,
+            ));
+
+        // Valid pattern: AB123
+        assert!(patterns.validate_text("AB123").is_ok());
+
+        // Invalid: number in alphabetic position
+        assert!(patterns.validate_text("A1123").is_err());
+
+        // Invalid: letter in numeric position
+        assert!(patterns.validate_text("AB1A3").is_err());
+    }
+
+    #[test]
+    fn test_custom_filter() {
+        let pattern = PatternFilters::new()
+            .add_filter(PositionFilter::new(
+                PositionRange::From(0),
+                CharacterFilter::Custom(Arc::new(|c| c.is_lowercase())),
+            ));
+
+        assert!(pattern.validate_text("hello").is_ok());
+        assert!(pattern.validate_text("Hello").is_err()); // Uppercase not allowed
+    }
+}
--- a/canvas/src/validation/state.rs
+++ b/canvas/src/validation/state.rs
@@ -0,0 +1,460 @@
+// src/validation/state.rs
+//! Validation state management
+
+use crate::validation::{ValidationConfig, ValidationResult, ExternalValidationState};
+use std::collections::HashMap;
+
+/// Validation state for all fields in a form
+#[derive(Debug, Clone, Default)]
+pub struct ValidationState {
+    /// Validation configurations per field index
+    field_configs: HashMap<usize, ValidationConfig>,
+    
+    /// Current validation results per field index
+    field_results: HashMap<usize, ValidationResult>,
+    
+    /// Track which fields have been validated
+    validated_fields: std::collections::HashSet<usize>,
+    
+    /// Global validation enabled/disabled
+    enabled: bool,
+
+    /// External validation results per field (Feature 5)
+    external_results: HashMap<usize, ExternalValidationState>,
+
+    last_switch_block: Option<String>,
+}
+
+impl ValidationState {
+    /// Create a new validation state
+    pub fn new() -> Self {
+        Self {
+            field_configs: HashMap::new(),
+            field_results: HashMap::new(),
+            validated_fields: std::collections::HashSet::new(),
+            enabled: true,
+            external_results: HashMap::new(),
+            last_switch_block: None,
+        }
+    }
+    
+    /// Enable or disable validation globally
+    pub fn set_enabled(&mut self, enabled: bool) {
+        self.enabled = enabled;
+        if !enabled {
+            // Clear all validation results when disabled
+            self.field_results.clear();
+            self.validated_fields.clear();
+            self.external_results.clear(); // Also clear external results
+        }
+    }
+    
+    /// Check if validation is enabled
+    pub fn is_enabled(&self) -> bool {
+        self.enabled
+    }
+    
+    /// Set validation configuration for a field
+    pub fn set_field_config(&mut self, field_index: usize, config: ValidationConfig) {
+        if config.has_validation() || config.external_validation_enabled {
+            self.field_configs.insert(field_index, config);
+        } else {
+            self.field_configs.remove(&field_index);
+            self.field_results.remove(&field_index);
+            self.validated_fields.remove(&field_index);
+            self.external_results.remove(&field_index);
+        }
+    }
+    
+    /// Get validation configuration for a field
+    pub fn get_field_config(&self, field_index: usize) -> Option<&ValidationConfig> {
+        self.field_configs.get(&field_index)
+    }
+    
+    /// Remove validation configuration for a field
+    pub fn remove_field_config(&mut self, field_index: usize) {
+        self.field_configs.remove(&field_index);
+        self.field_results.remove(&field_index);
+        self.validated_fields.remove(&field_index);
+        self.external_results.remove(&field_index);
+    }
+    
+    /// Set external validation state for a field (Feature 5)
+    pub fn set_external_validation(&mut self, field_index: usize, state: ExternalValidationState) {
+        self.external_results.insert(field_index, state);
+    }
+    
+    /// Get current external validation state for a field
+    pub fn get_external_validation(&self, field_index: usize) -> ExternalValidationState {
+        self.external_results
+            .get(&field_index)
+            .cloned()
+            .unwrap_or(ExternalValidationState::NotValidated)
+    }
+    
+    /// Clear external validation state for a field
+    pub fn clear_external_validation(&mut self, field_index: usize) {
+        self.external_results.remove(&field_index);
+    }
+    
+    /// Clear all external validation states
+    pub fn clear_all_external_validation(&mut self) {
+        self.external_results.clear();
+    }
+    
+    /// Validate character insertion for a field
+    pub fn validate_char_insertion(
+        &mut self,
+        field_index: usize,
+        current_text: &str,
+        position: usize,
+        character: char,
+    ) -> ValidationResult {
+        if !self.enabled {
+            return ValidationResult::Valid;
+        }
+        
+        if let Some(config) = self.field_configs.get(&field_index) {
+            let result = config.validate_char_insertion(current_text, position, character);
+            
+            // Store the validation result
+            self.field_results.insert(field_index, result.clone());
+            self.validated_fields.insert(field_index);
+            
+            result
+        } else {
+            ValidationResult::Valid
+        }
+    }
+    
+    /// Validate field content
+    pub fn validate_field_content(
+        &mut self,
+        field_index: usize,
+        text: &str,
+    ) -> ValidationResult {
+        if !self.enabled {
+            return ValidationResult::Valid;
+        }
+        
+        if let Some(config) = self.field_configs.get(&field_index) {
+            let result = config.validate_content(text);
+            
+            // Store the validation result
+            self.field_results.insert(field_index, result.clone());
+            self.validated_fields.insert(field_index);
+            
+            result
+        } else {
+            ValidationResult::Valid
+        }
+    }
+    
+    /// Get current validation result for a field
+    pub fn get_field_result(&self, field_index: usize) -> Option<&ValidationResult> {
+        self.field_results.get(&field_index)
+    }
+    
+    /// Get formatted display for a field if a custom formatter is configured.
+    /// Returns (formatted_text, position_mapper, optional_warning_message).
+    #[cfg(feature = "validation")]
+    pub fn formatted_for(
+        &self,
+        field_index: usize,
+        raw: &str,
+    ) -> Option<(String, std::sync::Arc<dyn crate::validation::PositionMapper>, Option<String>)> {
+        let config = self.field_configs.get(&field_index)?;
+        config.run_custom_formatter(raw)
+    }
+    
+    /// Check if a field has been validated
+    pub fn is_field_validated(&self, field_index: usize) -> bool {
+        self.validated_fields.contains(&field_index)
+    }
+    
+    /// Clear validation result for a field
+    pub fn clear_field_result(&mut self, field_index: usize) {
+        self.field_results.remove(&field_index);
+        self.validated_fields.remove(&field_index);
+    }
+    
+    /// Clear all validation results
+    pub fn clear_all_results(&mut self) {
+        self.field_results.clear();
+        self.validated_fields.clear();
+    }
+    
+    /// Get all field indices that have validation configured
+    pub fn validated_field_indices(&self) -> impl Iterator<Item = usize> + '_ {
+        self.field_configs.keys().copied()
+    }
+    
+    /// Get all field indices with validation errors
+    pub fn fields_with_errors(&self) -> impl Iterator<Item = usize> + '_ {
+        self.field_results
+            .iter()
+            .filter(|(_, result)| result.is_error())
+            .map(|(index, _)| *index)
+    }
+    
+    /// Get all field indices with validation warnings
+    pub fn fields_with_warnings(&self) -> impl Iterator<Item = usize> + '_ {
+        self.field_results
+            .iter()
+            .filter(|(_, result)| matches!(result, ValidationResult::Warning { .. }))
+            .map(|(index, _)| *index)
+    }
+    
+    /// Check if any field has validation errors
+    pub fn has_errors(&self) -> bool {
+        self.field_results.values().any(|result| result.is_error())
+    }
+    
+    /// Check if any field has validation warnings
+    pub fn has_warnings(&self) -> bool {
+        self.field_results.values().any(|result| matches!(result, ValidationResult::Warning { .. }))
+    }
+    
+    /// Get total count of fields with validation configured
+    pub fn validated_field_count(&self) -> usize {
+        self.field_configs.len()
+    }
+    
+    /// Check if field switching is allowed for a specific field
+    pub fn allows_field_switch(&self, field_index: usize, text: &str) -> bool {
+        if !self.enabled {
+            return true;
+        }
+        
+        if let Some(config) = self.field_configs.get(&field_index) {
+            config.allows_field_switch(text)
+        } else {
+            true // No validation configured, allow switching
+        }
+    }
+    
+    /// Get reason why field switching is blocked (if any)
+    pub fn field_switch_block_reason(&self, field_index: usize, text: &str) -> Option<String> {
+        if !self.enabled {
+            return None;
+        }
+        
+        if let Some(config) = self.field_configs.get(&field_index) {
+            config.field_switch_block_reason(text)
+        } else {
+            None // No validation configured
+        }
+    }
+    pub fn summary(&self) -> ValidationSummary {
+        let total_validated = self.validated_fields.len();
+        let errors = self.fields_with_errors().count();
+        let warnings = self.fields_with_warnings().count();
+        let valid = total_validated - errors - warnings;
+        
+        ValidationSummary {
+            total_fields: self.field_configs.len(),
+            validated_fields: total_validated,
+            valid_fields: valid,
+            warning_fields: warnings,
+            error_fields: errors,
+        }
+    }
+
+ 
+    /// Set the last switch block reason (for UI convenience)
+    pub fn set_last_switch_block<S: Into<String>>(&mut self, reason: S) {
+        self.last_switch_block = Some(reason.into());
+    }
+    
+    /// Clear the last switch block reason
+    pub fn clear_last_switch_block(&mut self) {
+        self.last_switch_block = None;
+    }
+    
+    /// Get the last switch block reason (if any)
+    pub fn last_switch_block(&self) -> Option<&str> {
+        self.last_switch_block.as_deref()
+    }
+}
+
+/// Summary of validation state across all fields
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct ValidationSummary {
+    /// Total number of fields with validation configured
+    pub total_fields: usize,
+    
+    /// Number of fields that have been validated
+    pub validated_fields: usize,
+    
+    /// Number of fields with valid validation results
+    pub valid_fields: usize,
+    
+    /// Number of fields with warnings
+    pub warning_fields: usize,
+    
+    /// Number of fields with errors
+    pub error_fields: usize,
+}
+
+impl ValidationSummary {
+    /// Check if all configured fields are valid
+    pub fn is_all_valid(&self) -> bool {
+        self.error_fields == 0 && self.validated_fields == self.total_fields
+    }
+    
+    /// Check if there are any errors
+    pub fn has_errors(&self) -> bool {
+        self.error_fields > 0
+    }
+    
+    /// Check if there are any warnings
+    pub fn has_warnings(&self) -> bool {
+        self.warning_fields > 0
+    }
+    
+    /// Get completion percentage (validated fields / total fields)
+    pub fn completion_percentage(&self) -> f32 {
+        if self.total_fields == 0 {
+            1.0
+        } else {
+            self.validated_fields as f32 / self.total_fields as f32
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::validation::{CharacterLimits, ValidationConfigBuilder};
+
+    #[test]
+    fn test_validation_state_creation() {
+        let state = ValidationState::new();
+        assert!(state.is_enabled());
+        assert_eq!(state.validated_field_count(), 0);
+    }
+    
+    #[test]
+    fn test_enable_disable() {
+        let mut state = ValidationState::new();
+        
+        // Add some validation config
+        let config = ValidationConfigBuilder::new()
+            .with_max_length(10)
+            .build();
+        state.set_field_config(0, config);
+        
+        // Validate something
+        let result = state.validate_field_content(0, "test");
+        assert!(result.is_acceptable());
+        assert!(state.is_field_validated(0));
+        
+        // Disable validation
+        state.set_enabled(false);
+        assert!(!state.is_enabled());
+        assert!(!state.is_field_validated(0)); // Should be cleared
+        
+        // Validation should now return valid regardless
+        let result = state.validate_field_content(0, "this is way too long for the limit");
+        assert!(result.is_acceptable());
+    }
+    
+    #[test]
+    fn test_field_config_management() {
+        let mut state = ValidationState::new();
+        
+        let config = ValidationConfigBuilder::new()
+            .with_max_length(5)
+            .build();
+        
+        // Set config
+        state.set_field_config(0, config);
+        assert_eq!(state.validated_field_count(), 1);
+        assert!(state.get_field_config(0).is_some());
+        
+        // Remove config
+        state.remove_field_config(0);
+        assert_eq!(state.validated_field_count(), 0);
+        assert!(state.get_field_config(0).is_none());
+    }
+    
+    #[test]
+    fn test_character_insertion_validation() {
+        let mut state = ValidationState::new();
+        
+        let config = ValidationConfigBuilder::new()
+            .with_max_length(5)
+            .build();
+        state.set_field_config(0, config);
+        
+        // Valid insertion
+        let result = state.validate_char_insertion(0, "test", 4, 'x');
+        assert!(result.is_acceptable());
+        
+        // Invalid insertion
+        let result = state.validate_char_insertion(0, "tests", 5, 'x');
+        assert!(!result.is_acceptable());
+        
+        // Check that result was stored
+        assert!(state.is_field_validated(0));
+        let stored_result = state.get_field_result(0);
+        assert!(stored_result.is_some());
+        assert!(!stored_result.unwrap().is_acceptable());
+    }
+    
+    #[test]
+    fn test_validation_summary() {
+        let mut state = ValidationState::new();
+        
+        // Configure two fields
+        let config1 = ValidationConfigBuilder::new().with_max_length(5).build();
+        let config2 = ValidationConfigBuilder::new().with_max_length(10).build();
+        state.set_field_config(0, config1);
+        state.set_field_config(1, config2);
+        
+        // Validate field 0 (valid)
+        state.validate_field_content(0, "test");
+        
+        // Validate field 1 (error)
+        state.validate_field_content(1, "this is too long");
+        
+        let summary = state.summary();
+        assert_eq!(summary.total_fields, 2);
+        assert_eq!(summary.validated_fields, 2);
+        assert_eq!(summary.valid_fields, 1);
+        assert_eq!(summary.error_fields, 1);
+        assert_eq!(summary.warning_fields, 0);
+        
+        assert!(!summary.is_all_valid());
+        assert!(summary.has_errors());
+        assert!(!summary.has_warnings());
+        assert_eq!(summary.completion_percentage(), 1.0);
+    }
+    
+    #[test]
+    fn test_error_and_warning_tracking() {
+        let mut state = ValidationState::new();
+        
+        let config = ValidationConfigBuilder::new()
+            .with_character_limits(
+                CharacterLimits::new_range(3, 10).with_warning_threshold(8)
+            )
+            .build();
+        state.set_field_config(0, config);
+        
+        // Too short (warning)
+        state.validate_field_content(0, "hi");
+        assert!(state.has_warnings());
+        assert!(!state.has_errors());
+        
+        // Just right
+        state.validate_field_content(0, "hello");
+        assert!(!state.has_warnings());
+        assert!(!state.has_errors());
+        
+        // Too long (error)
+        state.validate_field_content(0, "hello world!");
+        assert!(!state.has_warnings());
+        assert!(state.has_errors());
+    }
+}
--- a/canvas/view_docs.sh
+++ b/canvas/view_docs.sh
@@ -27,7 +27,7 @@ show_module() {

 # Main modules
 show_module "canvas" "CANVAS SYSTEM"
-show_module "autocomplete" "AUTOCOMPLETE SYSTEM" 
+show_module "suggestions" "SUGGESTIONS SYSTEM" 
 show_module "config" "CONFIGURATION SYSTEM"

 # Show lib.rs and other root files
@@ -45,7 +45,7 @@ fi
 echo -e "\n\033[1;36m=========================================="
 echo "To view specific module documentation:"
 echo "  ./view_canvas_docs.sh canvas"
-echo "  ./view_canvas_docs.sh autocomplete" 
+echo "  ./view_canvas_docs.sh suggestions" 
 echo "  ./view_canvas_docs.sh config"
 echo "==========================================\033[0m"

--- a/common/build.rs
+++ b/common/build.rs
@@ -15,6 +15,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                "proto/tables_data.proto",
                "proto/table_script.proto",
                "proto/search.proto",
+                "proto/search2.proto",
            ],
            &["proto"],
        )?;
--- a/common/proto/search2.proto
+++ b/common/proto/search2.proto
@@ -0,0 +1,46 @@
+// In common/proto/search2.proto
+syntax = "proto3";
+package komp_ac.search2;
+
+service Search2 {
+    rpc SearchTable(Search2Request) returns (Search2Response);
+}
+
+message Search2Request {
+  string profile_name = 1;
+  string table_name = 2;
+  repeated ColumnFilter column_filters = 3;
+  optional string text_query = 4;  // Optional fallback text search
+  optional int32 limit = 5;
+  optional string order_by = 6;
+  optional bool order_desc = 7;
+}
+
+message ColumnFilter {
+    string column_name = 1;
+    FilterType filter_type = 2;
+    string value = 3;
+    optional string value2 = 4;  // For range queries
+}
+
+enum FilterType {
+    EQUALS = 0;
+    CONTAINS = 1;
+    STARTS_WITH = 2;
+    ENDS_WITH = 3;
+    RANGE = 4;
+    GREATER_THAN = 5;
+    LESS_THAN = 6;
+    IS_NULL = 7;
+    IS_NOT_NULL = 8;
+}
+
+message Search2Response {
+    message Hit {
+        int64 id = 1;
+        string content_json = 2;  // No score - this is SQL-based
+        optional string match_info = 3;  // Info about which columns matched
+    }
+    repeated Hit hits = 1;
+    int32 total_count = 2;  // Total matching records (for pagination)
+}
--- a/common/src/lib.rs
+++ b/common/src/lib.rs
@@ -31,6 +31,9 @@ pub mod proto {
        pub mod search {
            include!("proto/komp_ac.search.rs");
        }
+        pub mod search2 {
+            include!("proto/komp_ac.search2.rs");
+        }
        pub const FILE_DESCRIPTOR_SET: &[u8] =
            include_bytes!("proto/descriptor.bin");
    }
--- a/common/src/proto/descriptor.bin
+++ b/common/src/proto/descriptor.bin
--- a/common/src/proto/komp_ac.search2.rs
+++ b/common/src/proto/komp_ac.search2.rs
@@ -0,0 +1,394 @@
+// This file is @generated by prost-build.
+#[derive(Clone, PartialEq, ::prost::Message)]
+pub struct Search2Request {
+    #[prost(string, tag = "1")]
+    pub profile_name: ::prost::alloc::string::String,
+    #[prost(string, tag = "2")]
+    pub table_name: ::prost::alloc::string::String,
+    #[prost(message, repeated, tag = "3")]
+    pub column_filters: ::prost::alloc::vec::Vec<ColumnFilter>,
+    /// Optional fallback text search
+    #[prost(string, optional, tag = "4")]
+    pub text_query: ::core::option::Option<::prost::alloc::string::String>,
+    #[prost(int32, optional, tag = "5")]
+    pub limit: ::core::option::Option<i32>,
+    #[prost(string, optional, tag = "6")]
+    pub order_by: ::core::option::Option<::prost::alloc::string::String>,
+    #[prost(bool, optional, tag = "7")]
+    pub order_desc: ::core::option::Option<bool>,
+}
+#[derive(Clone, PartialEq, ::prost::Message)]
+pub struct ColumnFilter {
+    #[prost(string, tag = "1")]
+    pub column_name: ::prost::alloc::string::String,
+    #[prost(enumeration = "FilterType", tag = "2")]
+    pub filter_type: i32,
+    #[prost(string, tag = "3")]
+    pub value: ::prost::alloc::string::String,
+    /// For range queries
+    #[prost(string, optional, tag = "4")]
+    pub value2: ::core::option::Option<::prost::alloc::string::String>,
+}
+#[derive(Clone, PartialEq, ::prost::Message)]
+pub struct Search2Response {
+    #[prost(message, repeated, tag = "1")]
+    pub hits: ::prost::alloc::vec::Vec<search2_response::Hit>,
+    /// Total matching records (for pagination)
+    #[prost(int32, tag = "2")]
+    pub total_count: i32,
+}
+/// Nested message and enum types in `Search2Response`.
+pub mod search2_response {
+    #[derive(Clone, PartialEq, ::prost::Message)]
+    pub struct Hit {
+        #[prost(int64, tag = "1")]
+        pub id: i64,
+        /// No score - this is SQL-based
+        #[prost(string, tag = "2")]
+        pub content_json: ::prost::alloc::string::String,
+        /// Info about which columns matched
+        #[prost(string, optional, tag = "3")]
+        pub match_info: ::core::option::Option<::prost::alloc::string::String>,
+    }
+}
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, PartialOrd, Ord, ::prost::Enumeration)]
+#[repr(i32)]
+pub enum FilterType {
+    Equals = 0,
+    Contains = 1,
+    StartsWith = 2,
+    EndsWith = 3,
+    Range = 4,
+    GreaterThan = 5,
+    LessThan = 6,
+    IsNull = 7,
+    IsNotNull = 8,
+}
+impl FilterType {
+    /// String value of the enum field names used in the ProtoBuf definition.
+    ///
+    /// The values are not transformed in any way and thus are considered stable
+    /// (if the ProtoBuf definition does not change) and safe for programmatic use.
+    pub fn as_str_name(&self) -> &'static str {
+        match self {
+            Self::Equals => "EQUALS",
+            Self::Contains => "CONTAINS",
+            Self::StartsWith => "STARTS_WITH",
+            Self::EndsWith => "ENDS_WITH",
+            Self::Range => "RANGE",
+            Self::GreaterThan => "GREATER_THAN",
+            Self::LessThan => "LESS_THAN",
+            Self::IsNull => "IS_NULL",
+            Self::IsNotNull => "IS_NOT_NULL",
+        }
+    }
+    /// Creates an enum from field names used in the ProtoBuf definition.
+    pub fn from_str_name(value: &str) -> ::core::option::Option<Self> {
+        match value {
+            "EQUALS" => Some(Self::Equals),
+            "CONTAINS" => Some(Self::Contains),
+            "STARTS_WITH" => Some(Self::StartsWith),
+            "ENDS_WITH" => Some(Self::EndsWith),
+            "RANGE" => Some(Self::Range),
+            "GREATER_THAN" => Some(Self::GreaterThan),
+            "LESS_THAN" => Some(Self::LessThan),
+            "IS_NULL" => Some(Self::IsNull),
+            "IS_NOT_NULL" => Some(Self::IsNotNull),
+            _ => None,
+        }
+    }
+}
+/// Generated client implementations.
+pub mod search2_client {
+    #![allow(
+        unused_variables,
+        dead_code,
+        missing_docs,
+        clippy::wildcard_imports,
+        clippy::let_unit_value,
+    )]
+    use tonic::codegen::*;
+    use tonic::codegen::http::Uri;
+    #[derive(Debug, Clone)]
+    pub struct Search2Client<T> {
+        inner: tonic::client::Grpc<T>,
+    }
+    impl Search2Client<tonic::transport::Channel> {
+        /// Attempt to create a new client by connecting to a given endpoint.
+        pub async fn connect<D>(dst: D) -> Result<Self, tonic::transport::Error>
+        where
+            D: TryInto<tonic::transport::Endpoint>,
+            D::Error: Into<StdError>,
+        {
+            let conn = tonic::transport::Endpoint::new(dst)?.connect().await?;
+            Ok(Self::new(conn))
+        }
+    }
+    impl<T> Search2Client<T>
+    where
+        T: tonic::client::GrpcService<tonic::body::Body>,
+        T::Error: Into<StdError>,
+        T::ResponseBody: Body<Data = Bytes> + std::marker::Send + 'static,
+        <T::ResponseBody as Body>::Error: Into<StdError> + std::marker::Send,
+    {
+        pub fn new(inner: T) -> Self {
+            let inner = tonic::client::Grpc::new(inner);
+            Self { inner }
+        }
+        pub fn with_origin(inner: T, origin: Uri) -> Self {
+            let inner = tonic::client::Grpc::with_origin(inner, origin);
+            Self { inner }
+        }
+        pub fn with_interceptor<F>(
+            inner: T,
+            interceptor: F,
+        ) -> Search2Client<InterceptedService<T, F>>
+        where
+            F: tonic::service::Interceptor,
+            T::ResponseBody: Default,
+            T: tonic::codegen::Service<
+                http::Request<tonic::body::Body>,
+                Response = http::Response<
+                    <T as tonic::client::GrpcService<tonic::body::Body>>::ResponseBody,
+                >,
+            >,
+            <T as tonic::codegen::Service<
+                http::Request<tonic::body::Body>,
+            >>::Error: Into<StdError> + std::marker::Send + std::marker::Sync,
+        {
+            Search2Client::new(InterceptedService::new(inner, interceptor))
+        }
+        /// Compress requests with the given encoding.
+        ///
+        /// This requires the server to support it otherwise it might respond with an
+        /// error.
+        #[must_use]
+        pub fn send_compressed(mut self, encoding: CompressionEncoding) -> Self {
+            self.inner = self.inner.send_compressed(encoding);
+            self
+        }
+        /// Enable decompressing responses.
+        #[must_use]
+        pub fn accept_compressed(mut self, encoding: CompressionEncoding) -> Self {
+            self.inner = self.inner.accept_compressed(encoding);
+            self
+        }
+        /// Limits the maximum size of a decoded message.
+        ///
+        /// Default: `4MB`
+        #[must_use]
+        pub fn max_decoding_message_size(mut self, limit: usize) -> Self {
+            self.inner = self.inner.max_decoding_message_size(limit);
+            self
+        }
+        /// Limits the maximum size of an encoded message.
+        ///
+        /// Default: `usize::MAX`
+        #[must_use]
+        pub fn max_encoding_message_size(mut self, limit: usize) -> Self {
+            self.inner = self.inner.max_encoding_message_size(limit);
+            self
+        }
+        pub async fn search_table(
+            &mut self,
+            request: impl tonic::IntoRequest<super::Search2Request>,
+        ) -> std::result::Result<
+            tonic::Response<super::Search2Response>,
+            tonic::Status,
+        > {
+            self.inner
+                .ready()
+                .await
+                .map_err(|e| {
+                    tonic::Status::unknown(
+                        format!("Service was not ready: {}", e.into()),
+                    )
+                })?;
+            let codec = tonic::codec::ProstCodec::default();
+            let path = http::uri::PathAndQuery::from_static(
+                "/komp_ac.search2.Search2/SearchTable",
+            );
+            let mut req = request.into_request();
+            req.extensions_mut()
+                .insert(GrpcMethod::new("komp_ac.search2.Search2", "SearchTable"));
+            self.inner.unary(req, path, codec).await
+        }
+    }
+}
+/// Generated server implementations.
+pub mod search2_server {
+    #![allow(
+        unused_variables,
+        dead_code,
+        missing_docs,
+        clippy::wildcard_imports,
+        clippy::let_unit_value,
+    )]
+    use tonic::codegen::*;
+    /// Generated trait containing gRPC methods that should be implemented for use with Search2Server.
+    #[async_trait]
+    pub trait Search2: std::marker::Send + std::marker::Sync + 'static {
+        async fn search_table(
+            &self,
+            request: tonic::Request<super::Search2Request>,
+        ) -> std::result::Result<tonic::Response<super::Search2Response>, tonic::Status>;
+    }
+    #[derive(Debug)]
+    pub struct Search2Server<T> {
+        inner: Arc<T>,
+        accept_compression_encodings: EnabledCompressionEncodings,
+        send_compression_encodings: EnabledCompressionEncodings,
+        max_decoding_message_size: Option<usize>,
+        max_encoding_message_size: Option<usize>,
+    }
+    impl<T> Search2Server<T> {
+        pub fn new(inner: T) -> Self {
+            Self::from_arc(Arc::new(inner))
+        }
+        pub fn from_arc(inner: Arc<T>) -> Self {
+            Self {
+                inner,
+                accept_compression_encodings: Default::default(),
+                send_compression_encodings: Default::default(),
+                max_decoding_message_size: None,
+                max_encoding_message_size: None,
+            }
+        }
+        pub fn with_interceptor<F>(
+            inner: T,
+            interceptor: F,
+        ) -> InterceptedService<Self, F>
+        where
+            F: tonic::service::Interceptor,
+        {
+            InterceptedService::new(Self::new(inner), interceptor)
+        }
+        /// Enable decompressing requests with the given encoding.
+        #[must_use]
+        pub fn accept_compressed(mut self, encoding: CompressionEncoding) -> Self {
+            self.accept_compression_encodings.enable(encoding);
+            self
+        }
+        /// Compress responses with the given encoding, if the client supports it.
+        #[must_use]
+        pub fn send_compressed(mut self, encoding: CompressionEncoding) -> Self {
+            self.send_compression_encodings.enable(encoding);
+            self
+        }
+        /// Limits the maximum size of a decoded message.
+        ///
+        /// Default: `4MB`
+        #[must_use]
+        pub fn max_decoding_message_size(mut self, limit: usize) -> Self {
+            self.max_decoding_message_size = Some(limit);
+            self
+        }
+        /// Limits the maximum size of an encoded message.
+        ///
+        /// Default: `usize::MAX`
+        #[must_use]
+        pub fn max_encoding_message_size(mut self, limit: usize) -> Self {
+            self.max_encoding_message_size = Some(limit);
+            self
+        }
+    }
+    impl<T, B> tonic::codegen::Service<http::Request<B>> for Search2Server<T>
+    where
+        T: Search2,
+        B: Body + std::marker::Send + 'static,
+        B::Error: Into<StdError> + std::marker::Send + 'static,
+    {
+        type Response = http::Response<tonic::body::Body>;
+        type Error = std::convert::Infallible;
+        type Future = BoxFuture<Self::Response, Self::Error>;
+        fn poll_ready(
+            &mut self,
+            _cx: &mut Context<'_>,
+        ) -> Poll<std::result::Result<(), Self::Error>> {
+            Poll::Ready(Ok(()))
+        }
+        fn call(&mut self, req: http::Request<B>) -> Self::Future {
+            match req.uri().path() {
+                "/komp_ac.search2.Search2/SearchTable" => {
+                    #[allow(non_camel_case_types)]
+                    struct SearchTableSvc<T: Search2>(pub Arc<T>);
+                    impl<T: Search2> tonic::server::UnaryService<super::Search2Request>
+                    for SearchTableSvc<T> {
+                        type Response = super::Search2Response;
+                        type Future = BoxFuture<
+                            tonic::Response<Self::Response>,
+                            tonic::Status,
+                        >;
+                        fn call(
+                            &mut self,
+                            request: tonic::Request<super::Search2Request>,
+                        ) -> Self::Future {
+                            let inner = Arc::clone(&self.0);
+                            let fut = async move {
+                                <T as Search2>::search_table(&inner, request).await
+                            };
+                            Box::pin(fut)
+                        }
+                    }
+                    let accept_compression_encodings = self.accept_compression_encodings;
+                    let send_compression_encodings = self.send_compression_encodings;
+                    let max_decoding_message_size = self.max_decoding_message_size;
+                    let max_encoding_message_size = self.max_encoding_message_size;
+                    let inner = self.inner.clone();
+                    let fut = async move {
+                        let method = SearchTableSvc(inner);
+                        let codec = tonic::codec::ProstCodec::default();
+                        let mut grpc = tonic::server::Grpc::new(codec)
+                            .apply_compression_config(
+                                accept_compression_encodings,
+                                send_compression_encodings,
+                            )
+                            .apply_max_message_size_config(
+                                max_decoding_message_size,
+                                max_encoding_message_size,
+                            );
+                        let res = grpc.unary(method, req).await;
+                        Ok(res)
+                    };
+                    Box::pin(fut)
+                }
+                _ => {
+                    Box::pin(async move {
+                        let mut response = http::Response::new(
+                            tonic::body::Body::default(),
+                        );
+                        let headers = response.headers_mut();
+                        headers
+                            .insert(
+                                tonic::Status::GRPC_STATUS,
+                                (tonic::Code::Unimplemented as i32).into(),
+                            );
+                        headers
+                            .insert(
+                                http::header::CONTENT_TYPE,
+                                tonic::metadata::GRPC_CONTENT_TYPE,
+                            );
+                        Ok(response)
+                    })
+                }
+            }
+        }
+    }
+    impl<T> Clone for Search2Server<T> {
+        fn clone(&self) -> Self {
+            let inner = self.inner.clone();
+            Self {
+                inner,
+                accept_compression_encodings: self.accept_compression_encodings,
+                send_compression_encodings: self.send_compression_encodings,
+                max_decoding_message_size: self.max_decoding_message_size,
+                max_encoding_message_size: self.max_encoding_message_size,
+            }
+        }
+    }
+    /// Generated gRPC service name
+    pub const SERVICE_NAME: &str = "komp_ac.search2.Search2";
+    impl<T> tonic::server::NamedService for Search2Server<T> {
+        const NAME: &'static str = SERVICE_NAME;
+    }
+}
--- a/server/src/auth/handlers/register.rs
+++ b/server/src/auth/handlers/register.rs
@@ -11,6 +11,11 @@ pub async fn register(
    pool: &PgPool,
    payload: RegisterRequest,
 ) -> Result<Response<AuthResponse>, Status> {
+    // Validate required fields
+    if payload.email.trim().is_empty() {
+        return Err(Status::invalid_argument("Email is required"));
+    }
+    
    // Validate passwords match
    if payload.password != payload.password_confirmation {
        return Err(Status::invalid_argument(AuthError::PasswordMismatch.to_string()));
@@ -41,6 +46,15 @@ pub async fn register(
            if db_err.constraint() == Some("valid_roles") {
                return Status::invalid_argument(format!("Invalid role specified: '{}'", role_to_insert));
            }
+            // Check for specific constraint violations
+            if let Some(constraint) = db_err.constraint() {
+                if constraint.contains("users_username_key") {
+                    return Status::already_exists("Username already exists".to_string());
+                }
+                if constraint.contains("users_email_key") {
+                    return Status::already_exists("Email already exists".to_string());
+                }
+            }
        }
        if e.to_string().contains("duplicate key") {
            Status::already_exists(AuthError::UserExists.to_string())
--- a/server/src/server/run.rs
+++ b/server/src/server/run.rs
@@ -10,14 +10,16 @@ use crate::server::services::{
    TableDefinitionService,
    TablesDataService,
    TableScriptService,
-    AuthServiceImpl
+    AuthServiceImpl,
+    Search2Service,
 };
 use common::proto::komp_ac::{
    table_structure::table_structure_service_server::TableStructureServiceServer,
    table_definition::table_definition_server::TableDefinitionServer,
    tables_data::tables_data_server::TablesDataServer,
    table_script::table_script_server::TableScriptServer,
-    auth::auth_service_server::AuthServiceServer
+    auth::auth_service_server::AuthServiceServer,
+    search2::search2_server::Search2Server,
 };
 use search::{SearcherService, SearcherServer};

@@ -47,9 +49,8 @@ pub async fn run_server(db_pool: sqlx::PgPool) -> Result<(), Box<dyn std::error:
    };
    let table_script_service = TableScriptService { db_pool: db_pool.clone() };
    let auth_service = AuthServiceImpl { db_pool: db_pool.clone() };
-
-    // MODIFIED: Instantiate SearcherService with the database pool
    let search_service = SearcherService { pool: db_pool.clone() };
+    let search2_service = Search2Service { db_pool: db_pool.clone() };

    Server::builder()
        .add_service(TableStructureServiceServer::new(TableStructureHandler { db_pool: db_pool.clone() }))
@@ -58,6 +59,7 @@ pub async fn run_server(db_pool: sqlx::PgPool) -> Result<(), Box<dyn std::error:
        .add_service(TableScriptServer::new(table_script_service))
        .add_service(AuthServiceServer::new(auth_service))
        .add_service(SearcherServer::new(search_service))
+        .add_service(Search2Server::new(search2_service))
        .add_service(reflection_service)
        .serve(addr)
        .await?;
--- a/server/src/server/services/mod.rs
+++ b/server/src/server/services/mod.rs
@@ -5,9 +5,11 @@ pub mod table_definition_service;
 pub mod tables_data_service;
 pub mod table_script_service;
 pub mod auth_service;
+pub mod search2_service;

 pub use table_structure_service::TableStructureHandler;
 pub use table_definition_service::TableDefinitionService;
 pub use tables_data_service::TablesDataService;
 pub use table_script_service::TableScriptService;
 pub use auth_service::AuthServiceImpl;
+pub use search2_service::*;
--- a/server/src/server/services/search2_service.rs
+++ b/server/src/server/services/search2_service.rs
@@ -0,0 +1,202 @@
+// src/server/services/search2_service.rs
+use tonic::{Request, Response, Status};
+use sqlx::PgPool;
+use sqlx::Row;
+use common::proto::komp_ac::search2::{
+    search2_server::Search2,
+    Search2Request, Search2Response, ColumnFilter, FilterType,
+    search2_response::Hit,
+};
+use crate::shared::schema_qualifier::qualify_table_name_for_data;
+
+pub struct Search2Service {
+    pub db_pool: PgPool,
+}
+
+#[tonic::async_trait]
+impl Search2 for Search2Service {
+    async fn search_table(
+        &self,
+        request: Request<Search2Request>,
+    ) -> Result<Response<Search2Response>, Status> {
+        let req = request.into_inner();
+
+        // Build SQL query - NOW PASS DB_POOL AND AWAIT
+        let (sql, bind_values, count_sql) = build_search_query(&self.db_pool, &req).await
+            .map_err(|e| Status::invalid_argument(format!("Query build error: {}", e)))?;
+
+        // Execute main query
+        let rows = execute_query(&self.db_pool, &sql, &bind_values).await
+            .map_err(|e| Status::internal(format!("Database error: {}", e)))?;
+
+        // Execute count query for pagination
+        let total_count = execute_count_query(&self.db_pool, &count_sql, &bind_values).await
+            .map_err(|e| Status::internal(format!("Count query error: {}", e)))?;
+
+        // Convert to response format
+        let hits = rows.into_iter().map(|row| {
+            Hit {
+                id: row.id,
+                content_json: row.content_json,
+                match_info: Some(format!("SQL search on table: {}", req.table_name)),
+            }
+        }).collect();
+
+        Ok(Response::new(Search2Response {
+            hits,
+            total_count,
+        }))
+    }
+}
+
+#[derive(Debug)]
+struct QueryRow {
+    id: i64,
+    content_json: String,
+}
+
+// MAKE THIS FUNCTION ASYNC AND ADD DB_POOL PARAMETER
+async fn build_search_query(
+    db_pool: &PgPool, 
+    request: &Search2Request
+) -> Result<(String, Vec<String>, String), String> {
+    
+    // Since Search2Request doesn't have profile_name, use "default"
+    // You can add profile_name to the proto later if needed
+    let profile_name = "default";
+    
+    // NOW AWAIT THE ASYNC FUNCTION CALL
+    let qualified_table = qualify_table_name_for_data(db_pool, profile_name, &request.table_name)
+        .await
+        .map_err(|e| format!("Invalid table name: {}", e))?;
+
+    let mut conditions = vec!["deleted = FALSE".to_string()];
+    let mut bind_values = Vec::new();
+
+    // Build WHERE conditions from column filters
+    for filter in &request.column_filters {
+        let condition = build_filter_condition(filter, &mut bind_values)?;
+        conditions.push(condition);
+    }
+
+    // Add text search fallback if provided
+    if let Some(text_query) = &request.text_query {
+        if !text_query.trim().is_empty() {
+            bind_values.push(format!("%{}%", text_query.to_lowercase()));
+            conditions.push(format!(
+                "EXISTS (SELECT 1 FROM jsonb_each_text(to_jsonb(t)) as kv(key, value) WHERE LOWER(value) LIKE ${})",
+                bind_values.len()
+            ));
+        }
+    }
+
+    let where_clause = conditions.join(" AND ");
+
+    // Build ORDER BY clause
+    let order_clause = if let Some(order_by) = &request.order_by {
+        let direction = if request.order_desc.unwrap_or(false) { "DESC" } else { "ASC" };
+        format!("ORDER BY \"{}\" {}", order_by, direction)
+    } else {
+        "ORDER BY id DESC".to_string()
+    };
+
+    let limit_clause = format!("LIMIT {}", request.limit.unwrap_or(100));
+
+    // Main query
+    let sql = format!(
+        "SELECT id, to_jsonb(t) AS data FROM {} t WHERE {} {} {}",
+        qualified_table, where_clause, order_clause, limit_clause
+    );
+
+    // Count query (for pagination)
+    let count_sql = format!(
+        "SELECT COUNT(*) FROM {} t WHERE {}",
+        qualified_table, where_clause
+    );
+
+    Ok((sql, bind_values, count_sql))
+}
+
+fn build_filter_condition(filter: &ColumnFilter, bind_values: &mut Vec<String>) -> Result<String, String> {
+    // FIX DEPRECATED WARNING - USE TryFrom INSTEAD
+    let filter_type = FilterType::try_from(filter.filter_type)
+        .map_err(|_| "Invalid filter type".to_string())?;
+
+    let param_idx = bind_values.len() + 1;
+
+    let condition = match filter_type {
+        FilterType::Equals => {
+            bind_values.push(filter.value.clone());
+            format!("\"{}\" = ${}", filter.column_name, param_idx)
+        },
+        FilterType::Contains => {
+            bind_values.push(format!("%{}%", filter.value));
+            format!("\"{}\" ILIKE ${}", filter.column_name, param_idx)
+        },
+        FilterType::StartsWith => {
+            bind_values.push(format!("{}%", filter.value));
+            format!("\"{}\" ILIKE ${}", filter.column_name, param_idx)
+        },
+        FilterType::EndsWith => {
+            bind_values.push(format!("%{}", filter.value));
+            format!("\"{}\" ILIKE ${}", filter.column_name, param_idx)
+        },
+        FilterType::Range => {
+            bind_values.push(filter.value.clone());
+            bind_values.push(filter.value2.as_ref().unwrap_or(&"".to_string()).clone());
+            format!("\"{}\" BETWEEN ${} AND ${}", filter.column_name, param_idx, param_idx + 1)
+        },
+        FilterType::GreaterThan => {
+            bind_values.push(filter.value.clone());
+            format!("\"{}\" > ${}", filter.column_name, param_idx)
+        },
+        FilterType::LessThan => {
+            bind_values.push(filter.value.clone());
+            format!("\"{}\" < ${}", filter.column_name, param_idx)
+        },
+        FilterType::IsNull => {
+            format!("\"{}\" IS NULL", filter.column_name)
+        },
+        FilterType::IsNotNull => {
+            format!("\"{}\" IS NOT NULL", filter.column_name)
+        },
+    };
+
+    Ok(condition)
+}
+
+async fn execute_query(pool: &PgPool, sql: &str, bind_values: &[String]) -> Result<Vec<QueryRow>, sqlx::Error> {
+    let mut query = sqlx::query(sql);
+
+    // Bind all parameters
+    for value in bind_values {
+        query = query.bind(value);
+    }
+
+    let rows = query.fetch_all(pool).await?;
+
+    let results = rows.into_iter().map(|row| {
+        QueryRow {
+            id: row.try_get("id").unwrap_or(0),
+            content_json: row.try_get::<serde_json::Value, _>("data")
+                .unwrap_or(serde_json::Value::Null)
+                .to_string(),
+        }
+    }).collect();
+
+    Ok(results)
+}
+
+async fn execute_count_query(pool: &PgPool, sql: &str, bind_values: &[String]) -> Result<i32, sqlx::Error> {
+    let mut query = sqlx::query(sql);
+
+    // Bind all parameters
+    for value in bind_values {
+        query = query.bind(value);
+    }
+
+    let row = query.fetch_one(pool).await?;
+    let count: i64 = row.try_get(0).unwrap_or(0);
+
+    Ok(count as i32)
+}
Author	SHA1	Message	Date
Priec	e36324af6f	working textarea with example, time to prepare it for the future implementations	2025-08-17 12:17:46 +02:00
Priec	60cb45dcca	first textarea implementation	2025-08-17 11:01:38 +02:00
Priec	215be3cf09	renamed capital lettered functions and fixed examples	2025-08-16 23:10:50 +02:00
Priec	b2aa966588	suggestions behind features flag only	2025-08-15 00:06:54 +02:00
Priec	67512ac151	src/editor.rs doesnt exist anymore	2025-08-15 00:06:19 +02:00
Priec	3f5dedbd6e	a bit of a cleanup, updated functionality of ge now working porperly well	2025-08-14 14:23:08 +02:00
Priec	ce07105eea	more vim functionality added	2025-08-14 00:08:18 +02:00
Priec	587470c48b	vim like behaviour is being built	2025-08-13 22:16:28 +02:00
Priec	3227d341ed	cleared codebase	2025-08-13 01:22:50 +02:00
Priec	2b16a80ef8	removed silenced variables	2025-08-12 09:53:24 +02:00
Priec	8b742bbe09	comments for reimplementation of autotrigger	2025-08-11 23:08:57 +02:00
Priec	189d3d2fc5	suggestions2 only on tab trigger and not automatic	2025-08-11 23:05:56 +02:00
Priec	082093ea17	compiled examples	2025-08-11 22:50:28 +02:00
Priec	280f314100	fixing examples	2025-08-11 12:41:42 +02:00
Priec	163a6262c8	proper example is being set	2025-08-11 12:03:56 +02:00
Priec	e8a564aed3	sugggestions are agnostic	2025-08-11 00:01:53 +02:00
filipriec	53464dfcbf	switch handled by the library from now on	2025-08-10 22:07:25 +02:00
filipriec	b364a6606d	fixing more code refactorization	2025-08-10 16:10:45 +02:00
Priec	f09e476bb6	working, restored	2025-08-10 12:20:43 +02:00
Priec	e2c9cc4347	WIP: staged changes before destructive reset	2025-08-10 11:03:31 +02:00
Priec	06106dc31b	improvements done by gpt5	2025-08-08 23:10:23 +02:00
Priec	8e3c85991c	fixed example, now working everything properly well	2025-08-07 23:30:31 +02:00
Priec	d3e5418221	fixed example of suggestions2	2025-08-07 20:05:39 +02:00
Priec	0d0e54032c	better suggestions2 example, not there yet	2025-08-07 18:51:45 +02:00
Priec	a8de16f66d	suggestions is getting more and more strong than ever before	2025-08-07 16:00:46 +02:00
Priec	5b2e0e976f	fixing examples	2025-08-07 13:51:59 +02:00
Priec	d601134535	computed fields are working perfectly well now	2025-08-07 12:38:09 +02:00
Priec	dff320d534	autocomplete to suggestions	2025-08-07 12:08:02 +02:00
Priec	96cde3ca0d	working examples 4 and 5	2025-08-07 00:23:45 +02:00
Priec	6ba0124779	feature5 implementation is full now	2025-08-07 00:03:11 +02:00
Priec	34c68858a3	feature4 implemented and working properly well	2025-08-06 23:16:04 +02:00
Priec	4c8cfd4f80	feature3 cursor bug fixed WARNING MIGHT BE BREAKING IF PROBLEMS, CHECK THIS COMMIT but it should be safe imo	2025-08-06 22:19:07 +02:00
Priec	85c5d7ccf9	feature3 with bug, needs a fix immidiately	2025-08-06 22:05:10 +02:00
Priec	46a0d2b9db	better example for feature2 being implemented and integrated into the codebase	2025-08-05 21:15:25 +02:00
Priec	c9b4841f67	validation2 example now working and displaying the full potential of the feature2 being implemented	2025-08-05 21:11:31 +02:00
Priec	d62cc2add6	feature2 implemented bug needs to be addressed	2025-08-05 19:22:30 +02:00
Priec	9c36e76eaa	validation of characters length is finished	2025-08-05 18:27:16 +02:00
Priec	abd8cba7a5	forgotten cargo lock	2025-08-05 00:12:25 +02:00
Priec	e6c4cb7e75	validation passed to the canvas library now compiled	2025-08-04 23:38:44 +02:00
filipriec	3d4435bac5	working colors in vim mode	2025-08-03 22:08:52 +02:00
filipriec	4146d0820b	line different color changed	2025-08-03 21:09:58 +02:00
filipriec	dbaa32f589	Merge branch 'main' of gitlab.com:filipriec/komp_ac	2025-08-03 07:53:36 +02:00
Priec	2b8eae67b9	highlight is now finally working	2025-08-02 23:31:03 +02:00
Priec	225bdc2bb6	Merge branch 'main' of gitlab.com:filipriec/komp_ac	2025-08-02 22:11:16 +02:00
Priec	8605ed1547	fixing issues in the edit/normal mode	2025-08-02 22:08:43 +02:00
filipriec	91cecabaca	append at the end of the line is being fully fixed now	2025-08-02 16:56:16 +02:00
filipriec	d4922233ae	Merge branch 'canvas' of gitlab.com:filipriec/komp_ac	2025-08-02 15:46:51 +02:00
filipriec	c00a214a0f	Merge branch 'main' of gitlab.com:filipriec/komp_ac	2025-08-02 15:42:56 +02:00
Priec	0baf152c3e	automatic cursor style handled by the library	2025-08-02 15:06:29 +02:00
Priec	c92c617314	exposed api to full vim mode	2025-08-02 13:41:21 +02:00
Priec	8c8ba53668	better example	2025-08-02 10:45:21 +02:00
Priec	2b08e64db8	fixed generics	2025-08-02 00:19:45 +02:00
Priec	643db8e586	removed deprecantions	2025-08-01 23:38:24 +02:00
Priec	5c39386a3a	completely redesign philosofy of this library	2025-08-01 22:54:05 +02:00
filipriec	a4e94878e7	enter decider should be taken care of next, suggestions works in register now also	2025-07-26 22:30:45 +02:00
filipriec	c7353ac81e	email is now required	2025-07-26 20:34:02 +02:00
filipriec	1fbc720620	updated	2025-07-26 19:05:08 +02:00
filipriec	263ccc3260	updated system	2025-07-26 08:49:09 +02:00
filipriec	00c0a399cd	sql search2 added	2025-07-25 22:38:34 +02:00