canvas compiled for the first time

canvas/src/actions/edit.rs

@@ -0,0 +1,416 @@
+// canvas/src/actions/edit.rs
+
+use crate::state::CanvasState;
+use crossterm::event::{KeyCode, KeyEvent};
+use anyhow::Result;
+
+/// Execute a generic edit action on any CanvasState implementation.
+/// This is the core function that makes the mode system work across all features.
+pub async fn execute_edit_action<S: CanvasState>(
+    action: &str,
+    key: KeyEvent,
+    state: &mut S,
+    ideal_cursor_column: &mut usize,
+) -> Result<String> {
+    // 1. Try feature-specific handler first (for autocomplete, field-specific logic, etc.)
+    let context = crate::state::ActionContext {
+        key_code: Some(key.code),
+        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(result);
+    }
+    
+    // 2. Handle suggestion-related actions generically
+    if handle_suggestion_actions(action, state)? {
+        return Ok("".to_string()); // Suggestion action handled
+    }
+    
+    // 3. Fall back to generic canvas actions (handles 95% of all actions)
+    handle_generic_action(action, key, state, ideal_cursor_column).await
+}
+
+/// Handle suggestion/autocomplete actions generically
+fn handle_suggestion_actions<S: CanvasState>(action: &str, state: &mut S) -> Result<bool> {
+    match action {
+        "suggestion_down" => {
+            if let Some(suggestions) = state.get_suggestions() {
+                if !suggestions.is_empty() {
+                    let current = state.get_selected_suggestion_index().unwrap_or(0);
+                    let next = (current + 1) % suggestions.len();
+                    state.set_selected_suggestion_index(Some(next));
+                    return Ok(true);
+                }
+            }
+            Ok(false)
+        }
+        "suggestion_up" => {
+            if let Some(suggestions) = state.get_suggestions() {
+                if !suggestions.is_empty() {
+                    let current = state.get_selected_suggestion_index().unwrap_or(0);
+                    let prev = if current == 0 { suggestions.len() - 1 } else { current - 1 };
+                    state.set_selected_suggestion_index(Some(prev));
+                    return Ok(true);
+                }
+            }
+            Ok(false)
+        }
+        "select_suggestion" => {
+            // Let feature handle this via handle_feature_action since it's feature-specific
+            Ok(false)
+        }
+        "exit_suggestions" => {
+            state.deactivate_suggestions();
+            Ok(true)
+        }
+        _ => Ok(false)
+    }
+}
+
+/// Handle generic canvas actions (movement, editing, etc.)
+async fn handle_generic_action<S: CanvasState>(
+    action: &str,
+    key: KeyEvent,
+    state: &mut S,
+    ideal_cursor_column: &mut usize,
+) -> Result<String> {
+    match action {
+        "insert_char" => {
+            if let KeyCode::Char(c) = key.code {
+                let cursor_pos = state.current_cursor_pos();
+                let field_value = state.get_current_input_mut();
+                let mut chars: Vec<char> = field_value.chars().collect();
+                if cursor_pos <= chars.len() {
+                    chars.insert(cursor_pos, c);
+                    *field_value = chars.into_iter().collect();
+                    state.set_current_cursor_pos(cursor_pos + 1);
+                    state.set_has_unsaved_changes(true);
+                    *ideal_cursor_column = state.current_cursor_pos();
+                }
+            } else {
+                return Ok("Error: insert_char called without a char key.".to_string());
+            }
+            Ok("".to_string())
+        }
+
+        "delete_char_backward" => {
+            if state.current_cursor_pos() > 0 {
+                let cursor_pos = state.current_cursor_pos();
+                let field_value = state.get_current_input_mut();
+                let mut chars: Vec<char> = field_value.chars().collect();
+                if cursor_pos <= chars.len() {
+                    chars.remove(cursor_pos - 1);
+                    *field_value = chars.into_iter().collect();
+                    let new_pos = cursor_pos - 1;
+                    state.set_current_cursor_pos(new_pos);
+                    state.set_has_unsaved_changes(true);
+                    *ideal_cursor_column = new_pos;
+                }
+            }
+            Ok("".to_string())
+        }
+
+        "delete_char_forward" => {
+            let cursor_pos = state.current_cursor_pos();
+            let field_value = state.get_current_input_mut();
+            let mut chars: Vec<char> = field_value.chars().collect();
+            if cursor_pos < chars.len() {
+                chars.remove(cursor_pos);
+                *field_value = chars.into_iter().collect();
+                state.set_has_unsaved_changes(true);
+                *ideal_cursor_column = cursor_pos;
+            }
+            Ok("".to_string())
+        }
+
+        "next_field" => {
+            let num_fields = state.fields().len();
+            if num_fields > 0 {
+                let current_field = state.current_field();
+                let new_field = (current_field + 1) % num_fields;
+                state.set_current_field(new_field);
+                let current_input = state.get_current_input();
+                let max_pos = current_input.len();
+                state.set_current_cursor_pos((*ideal_cursor_column).min(max_pos));
+            }
+            Ok("".to_string())
+        }
+
+        "prev_field" => {
+            let num_fields = state.fields().len();
+            if num_fields > 0 {
+                let current_field = state.current_field();
+                let new_field = if current_field == 0 {
+                    num_fields - 1
+                } else {
+                    current_field - 1
+                };
+                state.set_current_field(new_field);
+                let current_input = state.get_current_input();
+                let max_pos = current_input.len();
+                state.set_current_cursor_pos((*ideal_cursor_column).min(max_pos));
+            }
+            Ok("".to_string())
+        }
+
+        "move_left" => {
+            let new_pos = state.current_cursor_pos().saturating_sub(1);
+            state.set_current_cursor_pos(new_pos);
+            *ideal_cursor_column = new_pos;
+            Ok("".to_string())
+        }
+
+        "move_right" => {
+            let current_input = state.get_current_input();
+            let current_pos = state.current_cursor_pos();
+            if current_pos < current_input.len() {
+                let new_pos = current_pos + 1;
+                state.set_current_cursor_pos(new_pos);
+                *ideal_cursor_column = new_pos;
+            }
+            Ok("".to_string())
+        }
+
+        "move_up" => {
+            let num_fields = state.fields().len();
+            if num_fields > 0 {
+                let current_field = state.current_field();
+                let new_field = current_field.saturating_sub(1);
+                state.set_current_field(new_field);
+                let current_input = state.get_current_input();
+                let max_pos = current_input.len();
+                state.set_current_cursor_pos((*ideal_cursor_column).min(max_pos));
+            }
+            Ok("".to_string())
+        }
+
+        "move_down" => {
+            let num_fields = state.fields().len();
+            if num_fields > 0 {
+                let new_field = (state.current_field() + 1).min(num_fields - 1);
+                state.set_current_field(new_field);
+                let current_input = state.get_current_input();
+                let max_pos = current_input.len();
+                state.set_current_cursor_pos((*ideal_cursor_column).min(max_pos));
+            }
+            Ok("".to_string())
+        }
+
+        "move_line_start" => {
+            state.set_current_cursor_pos(0);
+            *ideal_cursor_column = 0;
+            Ok("".to_string())
+        }
+
+        "move_line_end" => {
+            let current_input = state.get_current_input();
+            let new_pos = current_input.len();
+            state.set_current_cursor_pos(new_pos);
+            *ideal_cursor_column = new_pos;
+            Ok("".to_string())
+        }
+
+        "move_first_line" => {
+            let num_fields = state.fields().len();
+            if num_fields > 0 {
+                state.set_current_field(0);
+                let current_input = state.get_current_input();
+                let max_pos = current_input.len();
+                state.set_current_cursor_pos((*ideal_cursor_column).min(max_pos));
+            }
+            Ok("Moved to first field".to_string())
+        }
+
+        "move_last_line" => {
+            let num_fields = state.fields().len();
+            if num_fields > 0 {
+                let new_field = num_fields - 1;
+                state.set_current_field(new_field);
+                let current_input = state.get_current_input();
+                let max_pos = current_input.len();
+                state.set_current_cursor_pos((*ideal_cursor_column).min(max_pos));
+            }
+            Ok("Moved to last field".to_string())
+        }
+
+        "move_word_next" => {
+            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 = new_pos.min(current_input.len());
+                state.set_current_cursor_pos(final_pos);
+                *ideal_cursor_column = final_pos;
+            }
+            Ok("".to_string())
+        }
+
+        "move_word_end" => {
+            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 = if new_pos == current_pos {
+                    find_word_end(current_input, new_pos + 1)
+                } else {
+                    new_pos
+                };
+
+                let max_valid_index = current_input.len().saturating_sub(1);
+                let clamped_pos = final_pos.min(max_valid_index);
+                state.set_current_cursor_pos(clamped_pos);
+                *ideal_cursor_column = clamped_pos;
+            }
+            Ok("".to_string())
+        }
+
+        "move_word_prev" => {
+            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("".to_string())
+        }
+
+        "move_word_end_prev" => {
+            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("Moved to previous word end".to_string())
+        }
+
+        _ => Ok(format!("Unknown or unhandled edit action: {}", action)),
+    }
+}
+
+// Word movement helper functions
+#[derive(PartialEq)]
+enum CharType {
+    Whitespace,
+    Alphanumeric,
+    Punctuation,
+}
+
+fn get_char_type(c: char) -> CharType {
+    if c.is_whitespace() {
+        CharType::Whitespace
+    } else if c.is_alphanumeric() {
+        CharType::Alphanumeric
+    } else {
+        CharType::Punctuation
+    }
+}
+
+fn find_next_word_start(text: &str, current_pos: usize) -> usize {
+    let chars: Vec<char> = text.chars().collect();
+    let len = chars.len();
+    if len == 0 || current_pos >= len {
+        return len;
+    }
+
+    let mut pos = current_pos;
+    let initial_type = get_char_type(chars[pos]);
+
+    while pos < len && get_char_type(chars[pos]) == initial_type {
+        pos += 1;
+    }
+
+    while pos < len && get_char_type(chars[pos]) == CharType::Whitespace {
+        pos += 1;
+    }
+
+    pos
+}
+
+fn find_word_end(text: &str, current_pos: usize) -> usize {
+    let chars: Vec<char> = text.chars().collect();
+    let len = chars.len();
+    if len == 0 {
+        return 0;
+    }
+
+    let mut pos = current_pos.min(len - 1);
+
+    if get_char_type(chars[pos]) == CharType::Whitespace {
+        pos = find_next_word_start(text, pos);
+    }
+
+    if pos >= len {
+        return len.saturating_sub(1);
+    }
+
+    let word_type = get_char_type(chars[pos]);
+    while pos < len && get_char_type(chars[pos]) == word_type {
+        pos += 1;
+    }
+
+    pos.saturating_sub(1).min(len.saturating_sub(1))
+}
+
+fn find_prev_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);
+
+    while pos > 0 && get_char_type(chars[pos]) == CharType::Whitespace {
+        pos -= 1;
+    }
+
+    if pos == 0 && get_char_type(chars[pos]) == CharType::Whitespace {
+        return 0;
+    }
+
+    let word_type = get_char_type(chars[pos]);
+    while pos > 0 && get_char_type(chars[pos - 1]) == word_type {
+        pos -= 1;
+    }
+
+    pos
+}
+
+fn find_prev_word_end(text: &str, current_pos: usize) -> usize {
+    let chars: Vec<char> = text.chars().collect();
+    let len = chars.len();
+    if len == 0 || current_pos == 0 {
+        return 0;
+    }
+
+    let mut pos = current_pos.saturating_sub(1);
+
+    while pos > 0 && get_char_type(chars[pos]) == CharType::Whitespace {
+        pos -= 1;
+    }
+
+    if pos == 0 && get_char_type(chars[pos]) == CharType::Whitespace {
+        return 0;
+    }
+    if pos == 0 && get_char_type(chars[pos]) != CharType::Whitespace {
+        return 0;
+    }
+
+    let word_type = get_char_type(chars[pos]);
+    while pos > 0 && get_char_type(chars[pos - 1]) == word_type {
+        pos -= 1;
+    }
+
+    while pos > 0 && get_char_type(chars[pos - 1]) == CharType::Whitespace {
+        pos -= 1;
+    }
+
+    if pos > 0 {
+        pos - 1
+    } else {
+        0
+    }
+}

canvas/src/actions/mod.rs

@@ -0,0 +1,3 @@
+// canvas/src/actions/mod.rs
+
+pub mod edit;

canvas/src/lib.rs

@@ -0,0 +1,30 @@
+// canvas/src/lib.rs
+
+//! Canvas - A reusable text editing and form canvas system
+//! 
+//! This crate provides a generic canvas abstraction for building text-based interfaces
+//! with multiple input fields, cursor management, and mode-based editing.
+
+pub mod state;
+pub mod actions;
+pub mod modes;
+pub mod suggestions;
+
+// Re-export the main types for easy use
+pub use state::{CanvasState, ActionContext};
+pub use actions::edit::execute_edit_action;
+pub use modes::{AppMode, ModeManager, HighlightState};
+pub use suggestions::SuggestionState;
+
+// High-level convenience API
+pub mod prelude {
+    pub use crate::{
+        CanvasState,
+        ActionContext,
+        execute_edit_action,
+        AppMode,
+        ModeManager,
+        HighlightState,
+        SuggestionState,
+    };
+}

canvas/src/modes/highlight.rs

@@ -0,0 +1,15 @@
+// src/state/app/highlight.rs
+// canvas/src/modes/highlight.rs
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum HighlightState {
+    Off,
+    Characterwise { anchor: (usize, usize) }, // (field_index, char_position)
+    Linewise { anchor_line: usize },          // field_index
+}
+
+impl Default for HighlightState {
+    fn default() -> Self {
+        HighlightState::Off
+    }
+}

canvas/src/modes/manager.rs

@@ -0,0 +1,34 @@
+// src/modes/handlers/mode_manager.rs
+// canvas/src/modes/manager.rs
+
+use crate::modes::highlight::HighlightState;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum AppMode {
+    General,   // For intro and admin screens
+    ReadOnly,  // Canvas read-only mode
+    Edit,      // Canvas edit mode
+    Highlight, // Canvas highlight/visual mode
+    Command,   // Command mode overlay
+}
+
+pub struct ModeManager;
+
+impl ModeManager {
+    // Mode transition rules
+    pub fn can_enter_command_mode(current_mode: AppMode) -> bool {
+        !matches!(current_mode, AppMode::Edit)
+    }
+
+    pub fn can_enter_edit_mode(current_mode: AppMode) -> bool {
+        matches!(current_mode, AppMode::ReadOnly)
+    }
+
+    pub fn can_enter_read_only_mode(current_mode: AppMode) -> bool {
+        matches!(current_mode, AppMode::Edit | AppMode::Command | AppMode::Highlight)
+    }
+
+    pub fn can_enter_highlight_mode(current_mode: AppMode) -> bool {
+        matches!(current_mode, AppMode::ReadOnly)
+    }
+}

canvas/src/modes/mod.rs

@@ -0,0 +1,7 @@
+// canvas/src/modes/mod.rs
+
+pub mod highlight;
+pub mod manager;
+
+pub use highlight::HighlightState;
+pub use manager::{AppMode, ModeManager};

canvas/src/state.rs

@@ -0,0 +1,64 @@
+// canvas/src/state.rs
+
+/// Context passed to feature-specific action handlers
+#[derive(Debug)]
+pub struct ActionContext {
+    pub key_code: Option<crossterm::event::KeyCode>,
+    pub ideal_cursor_column: usize,
+    pub current_input: String,
+    pub current_field: usize,
+}
+
+/// Core trait that any form-like state must implement to work with the canvas system.
+/// This enables the same mode behaviors (edit, read-only, highlight) to work across
+/// any implementation - login forms, data entry forms, configuration screens, etc.
+pub trait CanvasState {
+    // --- Core Navigation ---
+    fn current_field(&self) -> usize;
+    fn current_cursor_pos(&self) -> usize;
+    fn set_current_field(&mut self, index: usize);
+    fn set_current_cursor_pos(&mut self, pos: usize);
+
+    // --- Data Access ---
+    fn get_current_input(&self) -> &str;
+    fn get_current_input_mut(&mut self) -> &mut String;
+    fn inputs(&self) -> Vec<&String>;
+    fn fields(&self) -> Vec<&str>;
+
+    // --- State Management ---
+    fn has_unsaved_changes(&self) -> bool;
+    fn set_has_unsaved_changes(&mut self, changed: bool);
+
+    // --- Autocomplete/Suggestions (Optional) ---
+    fn get_suggestions(&self) -> Option<&[String]> {
+        None
+    }
+    fn get_selected_suggestion_index(&self) -> Option<usize> {
+        None
+    }
+    fn set_selected_suggestion_index(&mut self, _index: Option<usize>) {
+        // Default: no-op (override if you support suggestions)
+    }
+    fn activate_suggestions(&mut self, _suggestions: Vec<String>) {
+        // Default: no-op (override if you support suggestions)
+    }
+    fn deactivate_suggestions(&mut self) {
+        // Default: no-op (override if you support suggestions)  
+    }
+    
+    // --- Feature-specific action handling ---
+    fn handle_feature_action(&mut self, action: &str, context: &ActionContext) -> Option<String> {
+        None // Default: no feature-specific handling
+    }
+
+    // --- Display Overrides (for links, computed values, etc.) ---
+    fn get_display_value_for_field(&self, index: usize) -> &str {
+        self.inputs()
+            .get(index)
+            .map(|s| s.as_str())
+            .unwrap_or("")
+    }
+    fn has_display_override(&self, _index: usize) -> bool {
+        false
+    }
+}

canvas/src/suggestions.rs

@@ -0,0 +1,67 @@
+// canvas/src/suggestions.rs
+
+/// Generic suggestion system that can be implemented by any CanvasState
+#[derive(Debug, Clone)]
+pub struct SuggestionState {
+    pub suggestions: Vec<String>,
+    pub selected_index: Option<usize>,
+    pub is_active: bool,
+    pub trigger_chars: Vec<char>, // Characters that trigger suggestions
+}
+
+impl Default for SuggestionState {
+    fn default() -> Self {
+        Self {
+            suggestions: Vec::new(),
+            selected_index: None,
+            is_active: false,
+            trigger_chars: vec![], // No auto-trigger by default
+        }
+    }
+}
+
+impl SuggestionState {
+    pub fn new(trigger_chars: Vec<char>) -> Self {
+        Self {
+            trigger_chars,
+            ..Default::default()
+        }
+    }
+    
+    pub fn activate_with_suggestions(&mut self, suggestions: Vec<String>) {
+        self.suggestions = suggestions;
+        self.is_active = !self.suggestions.is_empty();
+        self.selected_index = if self.is_active { Some(0) } else { None };
+    }
+    
+    pub fn deactivate(&mut self) {
+        self.suggestions.clear();
+        self.selected_index = None;
+        self.is_active = false;
+    }
+    
+    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());
+        }
+    }
+    
+    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 }
+            );
+        }
+    }
+    
+    pub fn get_selected(&self) -> Option<&String> {
+        self.selected_index
+            .and_then(|idx| self.suggestions.get(idx))
+    }
+    
+    pub fn should_trigger(&self, c: char) -> bool {
+        self.trigger_chars.contains(&c)
+    }
+}