input pipeline is done in the library

examples/simple_input.rs

@@ -0,0 +1,55 @@
+extern crate alloc;
+
+use tui_orchestrator::input::{default_bindings, ComponentAction, InputError, InputSource, Key};
+
+struct MockInput {
+    keys: alloc::vec::Vec<Key>,
+    index: usize,
+}
+
+impl MockInput {
+    fn new(keys: alloc::vec::Vec<Key>) -> Self {
+        Self { keys, index: 0 }
+    }
+}
+
+impl InputSource for MockInput {
+    fn read_key(&mut self) -> Result<Key, InputError> {
+        if self.index < self.keys.len() {
+            let key = self.keys[self.index];
+            self.index += 1;
+            Ok(key)
+        } else {
+            Err(InputError::BackendError)
+        }
+    }
+}
+
+fn main() {
+    let bindings = default_bindings();
+    let mut input = MockInput::new(alloc::vec![Key::tab(), Key::enter(), Key::esc(),]);
+
+    loop {
+        match input.read_key() {
+            Ok(key) => {
+                if let Some(action) = bindings.get(&key) {
+                    match action {
+                        ComponentAction::Next => println!("Next"),
+                        ComponentAction::Select => println!("Select"),
+                        ComponentAction::Cancel => {
+                            println!("Cancel - exiting");
+                            break;
+                        }
+                        _ => println!("Other action: {:?}", action),
+                    }
+                } else {
+                    println!("No binding for key: {:?}", key);
+                }
+            }
+            Err(e) => {
+                println!("Error: {:?}", e);
+                break;
+            }
+        }
+    }
+}

src/input/action.rs

@@ -1,3 +1,35 @@
-// path_from_the_root: src/input/action.rs
+/// Marker trait for actions that can be bound to keys.
-
+///
+/// Actions must be cloneable, comparable, and debuggable.
 pub trait Action: Clone + PartialEq + Eq + core::fmt::Debug {}
+
+/// Default component actions for common TUI patterns.
+///
+/// These actions cover the most common TUI interactions:
+/// - Navigation (next, prev, first, last, directional)
+/// - Interaction (select, cancel)
+/// - Text input (type character, backspace, delete)
+/// - Custom actions via `Custom(usize)`
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum ComponentAction {
+    Next,
+    Prev,
+    First,
+    Last,
+    Select,
+    Cancel,
+    TypeChar(char),
+    Backspace,
+    Delete,
+    Home,
+    End,
+    PageUp,
+    PageDown,
+    Up,
+    Down,
+    Left,
+    Right,
+    Custom(usize),
+}
+
+impl Action for ComponentAction {}

src/input/bindings.rs

@@ -1,43 +1,98 @@
-// path_from_the_root: src/input/bindings.rs
+use super::action::{Action, ComponentAction};
-
-use super::action::Action;
 use super::key::Key;
 
 #[cfg(feature = "alloc")]
 use hashbrown::HashSet;
 
+/// Maps keys to actions.
+///
+/// When `alloc` feature is enabled, uses HashMap for O(1) lookup.
+/// Without `alloc`, falls back to Vec with O(n) lookup.
 #[derive(Debug, Clone)]
 pub struct Bindings<A: Action> {
+    #[cfg(feature = "alloc")]
+    bindings: hashbrown::HashMap<Key, A>,
+    #[cfg(not(feature = "alloc"))]
     bindings: alloc::vec::Vec<(Key, A)>,
 }
 
 impl<A: Action> Bindings<A> {
     pub fn new() -> Self {
         Self {
+            #[cfg(feature = "alloc")]
+            bindings: hashbrown::HashMap::new(),
+            #[cfg(not(feature = "alloc"))]
             bindings: alloc::vec::Vec::new(),
         }
     }
 
     pub fn bind(&mut self, key: Key, action: A) {
+        #[cfg(feature = "alloc")]
+        {
+            self.bindings.insert(key, action);
+        }
+        #[cfg(not(feature = "alloc"))]
+        {
             self.bindings.push((key, action));
         }
+    }
 
     pub fn get(&self, key: &Key) -> Option<&A> {
+        #[cfg(feature = "alloc")]
+        {
+            self.bindings.get(key)
+        }
+        #[cfg(not(feature = "alloc"))]
+        {
             self.bindings.iter().find(|(k, _)| k == key).map(|(_, a)| a)
         }
+    }
 
     pub fn remove(&mut self, key: &Key) {
+        #[cfg(feature = "alloc")]
+        {
+            self.bindings.remove(key);
+        }
+        #[cfg(not(feature = "alloc"))]
+        {
             self.bindings.retain(|(k, _)| k != key);
         }
+    }
 
     pub fn is_empty(&self) -> bool {
+        #[cfg(feature = "alloc")]
+        {
             self.bindings.is_empty()
         }
+        #[cfg(not(feature = "alloc"))]
+        {
+            self.bindings.is_empty()
+        }
+    }
 
     pub fn len(&self) -> usize {
+        #[cfg(feature = "alloc")]
+        {
             self.bindings.len()
         }
+        #[cfg(not(feature = "alloc"))]
+        {
+            self.bindings.len()
+        }
+    }
 
+    pub fn keys(&self) -> alloc::vec::Vec<&Key> {
+        #[cfg(feature = "alloc")]
+        {
+            self.bindings.keys().collect()
+        }
+        #[cfg(not(feature = "alloc"))]
+        {
+            self.bindings.iter().map(|(k, _)| k).collect()
+        }
+    }
+
+    #[cfg(not(feature = "alloc"))]
     pub fn iter(&self) -> impl Iterator<Item = &(Key, A)> {
         self.bindings.iter()
     }
@@ -52,19 +107,71 @@ impl<A: Action> Default for Bindings<A> {
 #[cfg(feature = "sequences")]
 impl<A: Action + core::hash::Hash + Eq> Bindings<A> {
     pub fn bind_sequence(&mut self, keys: alloc::vec::Vec<Key>, action: A) {
+        #[cfg(feature = "alloc")]
+        {
+            for key in keys {
+                self.bindings.insert(key, action.clone());
+            }
+        }
+        #[cfg(not(feature = "alloc"))]
+        {
             for key in keys {
                 self.bindings.push((key, action.clone()));
             }
         }
+    }
 
     pub fn get_sequences(&self) -> alloc::vec::Vec<&A> {
         let mut actions = alloc::vec::Vec::new();
         let mut seen = HashSet::new();
+        #[cfg(feature = "alloc")]
+        {
             for (_, action) in &self.bindings {
                 if seen.insert(action) {
                     actions.push(action);
                 }
             }
+        }
+        #[cfg(not(feature = "alloc"))]
+        {
+            for (_, action) in &self.bindings {
+                if seen.insert(action) {
+                    actions.push(action);
+                }
+            }
+        }
         actions
     }
 }
+
+/// Returns default key bindings for common TUI patterns.
+///
+/// Includes:
+/// - Tab/Shift+Tab for next/prev navigation
+/// - Enter for select
+/// - Esc for cancel
+/// - Arrow keys for directional movement
+/// - Home/End/PageUp/PageDown for scrolling
+/// - Backspace/Delete for editing
+/// - Ctrl+C as custom quit action
+///
+/// Use as-is or extend with your own bindings.
+pub fn default_bindings() -> Bindings<ComponentAction> {
+    let mut bindings = Bindings::new();
+    bindings.bind(Key::tab(), ComponentAction::Next);
+    bindings.bind(Key::shift_tab(), ComponentAction::Prev);
+    bindings.bind(Key::enter(), ComponentAction::Select);
+    bindings.bind(Key::esc(), ComponentAction::Cancel);
+    bindings.bind(Key::home(), ComponentAction::Home);
+    bindings.bind(Key::end(), ComponentAction::End);
+    bindings.bind(Key::page_up(), ComponentAction::PageUp);
+    bindings.bind(Key::page_down(), ComponentAction::PageDown);
+    bindings.bind(Key::up(), ComponentAction::Up);
+    bindings.bind(Key::down(), ComponentAction::Down);
+    bindings.bind(Key::left(), ComponentAction::Left);
+    bindings.bind(Key::right(), ComponentAction::Right);
+    bindings.bind(Key::backspace(), ComponentAction::Backspace);
+    bindings.bind(Key::delete(), ComponentAction::Delete);
+    bindings.bind(Key::ctrl('c'), ComponentAction::Custom(0));
+    bindings
+}

src/input/handler.rs

@@ -1,5 +1,3 @@
-// path_from_the_root: src/input/handler.rs
-
 #[cfg(feature = "sequences")]
 use super::action::Action;
 
@@ -9,10 +7,20 @@ use super::key::Key;
 #[cfg(feature = "sequences")]
 use super::result::MatchResult;
 
+#[cfg(all(feature = "sequences", feature = "std"))]
+extern crate std;
+
+#[cfg(all(feature = "sequences", feature = "std"))]
+use std::time::{Duration, Instant};
+
 #[cfg(feature = "sequences")]
 pub struct SequenceHandler<A: Action> {
     sequences: alloc::vec::Vec<(alloc::vec::Vec<Key>, A)>,
     current: alloc::vec::Vec<Key>,
+    #[cfg(feature = "std")]
+    last_timestamp: Option<Instant>,
+    #[cfg(feature = "std")]
+    timeout: Duration,
 }
 
 #[cfg(feature = "sequences")]
@@ -21,6 +29,17 @@ impl<A: Action> SequenceHandler<A> {
         Self {
             sequences: alloc::vec::Vec::new(),
             current: alloc::vec::Vec::new(),
+            #[cfg(feature = "std")]
+            last_timestamp: None,
+            #[cfg(feature = "std")]
+            timeout: Duration::from_millis(500),
+        }
+    }
+
+    pub fn with_timeout_ms(&mut self, ms: u64) {
+        #[cfg(feature = "std")]
+        {
+            self.timeout = Duration::from_millis(ms);
         }
     }
 
@@ -30,6 +49,16 @@ impl<A: Action> SequenceHandler<A> {
     }
 
     pub fn handle(&mut self, key: Key) -> MatchResult<A> {
+        #[cfg(feature = "std")]
+        {
+            if let Some(last) = self.last_timestamp {
+                if last.elapsed() > self.timeout {
+                    self.current.clear();
+                }
+            }
+            self.last_timestamp = Some(Instant::now());
+        }
+
         self.current.push(key);
 
         for (seq, action) in &self.sequences {

src/input/key.rs

@@ -1,5 +1,7 @@
-// path_from_the_root: src/input/key.rs
+/// Represents a key code without modifiers.
-
+///
+/// This includes character keys, special keys (Enter, Tab, Esc, etc.),
+/// and function keys F1-F255.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub enum KeyCode {
     Char(char),
@@ -20,6 +22,9 @@ pub enum KeyCode {
     Null,
 }
 
+/// Represents key modifier flags (Control, Alt, Shift).
+///
+/// These modifiers can be combined with any key code.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Default)]
 pub struct KeyModifiers {
     pub control: bool,
@@ -56,6 +61,9 @@ impl KeyModifiers {
     }
 }
 
+/// Represents a complete key press with modifiers.
+///
+/// This is the main type used throughout the input system.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct Key {
     pub code: KeyCode,
@@ -81,6 +89,125 @@ impl Key {
         }
     }
 
+    pub const fn shift_tab() -> Self {
+        Self {
+            code: KeyCode::Tab,
+            modifiers: KeyModifiers::new().with_shift(),
+        }
+    }
+
+    pub const fn alt_char(c: char) -> Self {
+        Self {
+            code: KeyCode::Char(c),
+            modifiers: KeyModifiers::new().with_alt(),
+        }
+    }
+
+    pub const fn ctrl_shift_char(c: char) -> Self {
+        Self {
+            code: KeyCode::Char(c),
+            modifiers: KeyModifiers::new().with_control().with_shift(),
+        }
+    }
+
+    pub const fn alt_ctrl_char(c: char) -> Self {
+        Self {
+            code: KeyCode::Char(c),
+            modifiers: KeyModifiers::new().with_alt().with_control(),
+        }
+    }
+
+    pub const fn enter() -> Self {
+        Self {
+            code: KeyCode::Enter,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn esc() -> Self {
+        Self {
+            code: KeyCode::Esc,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn backspace() -> Self {
+        Self {
+            code: KeyCode::Backspace,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn delete() -> Self {
+        Self {
+            code: KeyCode::Delete,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn tab() -> Self {
+        Self {
+            code: KeyCode::Tab,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn page_up() -> Self {
+        Self {
+            code: KeyCode::PageUp,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn page_down() -> Self {
+        Self {
+            code: KeyCode::PageDown,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn up() -> Self {
+        Self {
+            code: KeyCode::Up,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn down() -> Self {
+        Self {
+            code: KeyCode::Down,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn left() -> Self {
+        Self {
+            code: KeyCode::Left,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn right() -> Self {
+        Self {
+            code: KeyCode::Right,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn home() -> Self {
+        Self {
+            code: KeyCode::Home,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
+    pub const fn end() -> Self {
+        Self {
+            code: KeyCode::End,
+            modifiers: KeyModifiers::new(),
+        }
+    }
+
     pub fn display_string(&self) -> alloc::string::String {
         let mut out = alloc::string::String::new();
         if self.modifiers.control {

src/input/mod.rs

@@ -5,11 +5,13 @@ pub mod bindings;
 pub mod handler;
 pub mod key;
 pub mod result;
+pub mod source;
 
-pub use action::Action;
+pub use action::{Action, ComponentAction};
-pub use bindings::Bindings;
+pub use bindings::{default_bindings, Bindings};
 pub use key::{Key, KeyCode, KeyModifiers};
 pub use result::MatchResult;
+pub use source::{InputError, InputSource};
 
 #[cfg(feature = "sequences")]
 pub use handler::SequenceHandler;

src/input/result.rs

@@ -1,5 +1,8 @@
-// path_from_the_root: src/input/result.rs
+/// Result of matching a key or sequence.
-
+///
+/// - `Match(action)` - Key or sequence matched, returns the action
+/// - `Pending` - Sequence in progress, waiting for more keys
+/// - `NoMatch` - No binding found
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum MatchResult<A> {
     Match(A),

src/input/source.rs

@@ -0,0 +1,38 @@
+use super::key::Key;
+
+/// Errors that can occur when reading input.
+#[derive(Debug)]
+pub enum InputError {
+    NotAKeyEvent,
+    BackendError,
+}
+
+/// Trait for reading keys from a backend.
+///
+/// Users implement this trait to bridge to crossterm, termion,
+/// or any other terminal backend.
+///
+/// Example with crossterm:
+///
+/// ```ignore
+/// use crossterm::event;
+///
+/// struct CrosstermInput;
+///
+/// impl InputSource for CrosstermInput {
+///     fn read_key(&mut self) -> Result<Key, InputError> {
+///         match event::read()? {
+///             event::Event::Key(key_event) => {
+///                 Ok(Key::new(
+///                     KeyCode::from(key_event.code),
+///                     KeyModifiers::from(key_event.modifiers),
+///                 ))
+///             }
+///             _ => Err(InputError::NotAKeyEvent),
+///         }
+///     }
+/// }
+/// ```
+pub trait InputSource {
+    fn read_key(&mut self) -> Result<Key, InputError>;
+}