working keymap

canvas/src/keymap/mod.rs

@@ -0,0 +1,344 @@
+// src/keymap/mod.rs
+use std::collections::HashMap;
+use std::time::{Duration, Instant};
+
+use crossterm::event::{KeyCode, KeyModifiers};
+
+use crate::canvas::modes::AppMode;
+
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
+pub struct KeyStroke {
+    pub code: KeyCode,
+    pub modifiers: KeyModifiers,
+}
+
+#[derive(Clone, Debug)]
+struct Binding {
+    action: String,
+    sequence: Vec<KeyStroke>,
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct CanvasKeyMap {
+    ro: Vec<Binding>,
+    edit: Vec<Binding>,
+    hl: Vec<Binding>,
+}
+
+// FIXED: Removed Copy because Option<String> is not Copy
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum KeyEventOutcome {
+    Consumed(Option<String>),
+    Pending,
+    NotMatched,
+}
+
+#[derive(Debug, Clone)]
+pub struct KeySequenceTracker {
+    sequence: Vec<KeyStroke>,
+    last_key_time: Instant,
+    timeout: Duration,
+}
+
+impl KeySequenceTracker {
+    pub fn new(timeout_ms: u64) -> Self {
+        Self {
+            sequence: Vec::new(),
+            last_key_time: Instant::now(),
+            timeout: Duration::from_millis(timeout_ms),
+        }
+    }
+
+    pub fn reset(&mut self) {
+        self.sequence.clear();
+        self.last_key_time = Instant::now();
+    }
+
+    pub fn add_key(&mut self, stroke: KeyStroke) {
+        let now = Instant::now();
+        if now.duration_since(self.last_key_time) > self.timeout {
+            self.reset();
+        }
+        self.sequence.push(normalize_stroke(stroke));
+        self.last_key_time = now;
+    }
+
+    pub fn sequence(&self) -> &[KeyStroke] {
+        &self.sequence
+    }
+}
+
+fn normalize_stroke(mut s: KeyStroke) -> KeyStroke {
+    // Normalize Shift+Tab to BackTab
+    let is_shift_tab =
+        s.code == KeyCode::Tab && s.modifiers.contains(KeyModifiers::SHIFT);
+    if is_shift_tab {
+        s.code = KeyCode::BackTab;
+        s.modifiers.remove(KeyModifiers::SHIFT);
+        return s;
+    }
+
+    // Normalize Shift+char to uppercase char without SHIFT when possible
+    if let KeyCode::Char(c) = s.code {
+        if s.modifiers.contains(KeyModifiers::SHIFT) {
+            let mut up = c;
+            // Only letters transform meaningfully
+            if c.is_ascii_alphabetic() {
+                up = c.to_ascii_uppercase();
+            }
+            s.code = KeyCode::Char(up);
+            s.modifiers.remove(KeyModifiers::SHIFT);
+            return s;
+        }
+    }
+    s
+}
+
+impl CanvasKeyMap {
+    pub fn from_mode_maps(
+        read_only: &HashMap<String, Vec<String>>,
+        edit: &HashMap<String, Vec<String>>,
+        highlight: &HashMap<String, Vec<String>>,
+    ) -> Self {
+        let mut km = Self::default();
+        km.ro = collect_bindings(read_only);
+        km.edit = collect_bindings(edit);
+        km.hl = collect_bindings(highlight);
+        km
+    }
+
+    pub fn lookup(
+        &self,
+        mode: AppMode,
+        seq: &[KeyStroke],
+    ) -> (Option<&str>, bool) {
+        let bindings = match mode {
+            AppMode::ReadOnly => &self.ro,
+            AppMode::Edit => &self.edit,
+            AppMode::Highlight => &self.hl,
+            _ => return (None, false),
+        };
+
+        if seq.is_empty() {
+            return (None, false);
+        }
+
+        // Exact match
+        for b in bindings {
+            if sequences_equal(&b.sequence, seq) {
+                return (Some(b.action.as_str()), false);
+            }
+        }
+
+        // Prefix match
+        for b in bindings {
+            if is_prefix(&b.sequence, seq) {
+                return (None, true);
+            }
+        }
+
+        (None, false)
+    }
+}
+
+fn sequences_equal(a: &[KeyStroke], b: &[KeyStroke]) -> bool {
+    if a.len() != b.len() {
+        return false;
+    }
+    a.iter().zip(b.iter()).all(|(x, y)| strokes_equal(x, y))
+}
+
+fn strokes_equal(a: &KeyStroke, b: &KeyStroke) -> bool {
+    // Both KeyStroke are already normalized
+    a.code == b.code && a.modifiers == b.modifiers
+}
+
+fn is_prefix(binding: &[KeyStroke], seq: &[KeyStroke]) -> bool {
+    if seq.len() >= binding.len() {
+        return false;
+    }
+    binding
+        .iter()
+        .zip(seq.iter())
+        .all(|(b, s)| strokes_equal(b, s))
+}
+
+fn collect_bindings(
+    mode_map: &HashMap<String, Vec<String>>,
+) -> Vec<Binding> {
+    let mut out = Vec::new();
+    for (action, list) in mode_map {
+        for binding_str in list {
+            if let Some(seq) = parse_binding_to_sequence(binding_str) {
+                out.push(Binding {
+                    action: action.to_string(),
+                    sequence: seq,
+                });
+            }
+        }
+    }
+    out
+}
+
+fn parse_binding_to_sequence(input: &str) -> Option<Vec<KeyStroke>> {
+    let s = input.trim();
+    if s.is_empty() {
+        return None;
+    }
+
+    let has_space = s.contains(' ');
+    let has_plus = s.contains('+');
+
+    if has_space {
+        let mut seq = Vec::new();
+        for part in s.split_whitespace() {
+            if let Some(mut strokes) = parse_part_to_sequence(part) {
+                seq.append(&mut strokes);
+            } else {
+                return None;
+            }
+        }
+        return Some(seq);
+    }
+
+    if has_plus {
+        if contains_modifier_token(s) {
+            if let Some(k) = parse_chord_with_modifiers(s) {
+                return Some(vec![k]);
+            }
+            return None;
+        } else {
+            let mut seq = Vec::new();
+            for t in s.split('+') {
+                if let Some(mut strokes) = parse_part_to_sequence(t) {
+                    seq.append(&mut strokes);
+                } else {
+                    return None;
+                }
+            }
+            return Some(seq);
+        }
+    }
+
+    if is_compound_key(s) {
+        if let Some(k) = parse_simple_key(s) {
+            return Some(vec![k]);
+        }
+        return None;
+    }
+
+    if s.len() > 1 {
+        let mut seq = Vec::new();
+        for ch in s.chars() {
+            seq.push(KeyStroke {
+                code: KeyCode::Char(ch),
+                modifiers: KeyModifiers::empty(),
+            });
+        }
+        return Some(seq);
+    }
+
+    if let Some(k) = parse_simple_key(s) {
+        return Some(vec![k]);
+    }
+    None
+}
+
+fn parse_part_to_sequence(part: &str) -> Option<Vec<KeyStroke>> {
+    let p = part.trim();
+    if p.is_empty() {
+        return None;
+    }
+
+    if p.contains('+') && contains_modifier_token(p) {
+        if let Some(k) = parse_chord_with_modifiers(p) {
+            return Some(vec![k]);
+        }
+        return None;
+    }
+
+    if is_compound_key(p) {
+        if let Some(k) = parse_simple_key(p) {
+            return Some(vec![k]);
+        }
+        return None;
+    }
+
+    if p.len() > 1 {
+        let mut seq = Vec::new();
+        for ch in p.chars() {
+            seq.push(KeyStroke {
+                code: KeyCode::Char(ch),
+                modifiers: KeyModifiers::empty(),
+            });
+        }
+        return Some(seq);
+    }
+
+    parse_simple_key(p).map(|k| vec![k])
+}
+
+fn contains_modifier_token(s: &str) -> bool {
+    let low = s.to_lowercase();
+    low.contains("ctrl") || low.contains("shift") || low.contains("alt") || 
+    low.contains("super") || low.contains("cmd") || low.contains("meta")
+}
+
+fn parse_chord_with_modifiers(s: &str) -> Option<KeyStroke> {
+    let mut mods = KeyModifiers::empty();
+    let mut key: Option<KeyCode> = None;
+
+    for comp in s.split('+') {
+        match comp.to_lowercase().as_str() {
+            "ctrl" => mods |= KeyModifiers::CONTROL,
+            "shift" => mods |= KeyModifiers::SHIFT,
+            "alt" => mods |= KeyModifiers::ALT,
+            "super" | "cmd" => mods |= KeyModifiers::SUPER,
+            "meta" => mods |= KeyModifiers::META,
+            other => {
+                key = string_to_keycode(other);
+            }
+        }
+    }
+
+    key.map(|k| normalize_stroke(KeyStroke { code: k, modifiers: mods }))
+}
+
+fn is_compound_key(s: &str) -> bool {
+    matches!(s.to_lowercase().as_str(),
+        "left" | "right" | "up" | "down" | "esc" | "enter" | "backspace" | 
+        "delete" | "tab" | "home" | "end" | "$" | "0"
+    )
+}
+
+fn parse_simple_key(s: &str) -> Option<KeyStroke> {
+    if let Some(kc) = string_to_keycode(&s.to_lowercase()) {
+        return Some(KeyStroke { code: kc, modifiers: KeyModifiers::empty() });
+    }
+
+    if s.chars().count() == 1 {
+        let ch = s.chars().next().unwrap();
+        return Some(KeyStroke { code: KeyCode::Char(ch), modifiers: KeyModifiers::empty() });
+    }
+
+    None
+}
+
+fn string_to_keycode(s: &str) -> Option<KeyCode> {
+    Some(match s {
+        "left" => KeyCode::Left,
+        "right" => KeyCode::Right, 
+        "up" => KeyCode::Up,
+        "down" => KeyCode::Down,
+        "esc" => KeyCode::Esc,
+        "enter" => KeyCode::Enter,
+        "backspace" => KeyCode::Backspace,
+        "delete" => KeyCode::Delete,
+        "tab" => KeyCode::Tab,
+        "home" => KeyCode::Home,
+        "end" => KeyCode::End,
+        "$" => KeyCode::Char('$'),
+        "0" => KeyCode::Char('0'),
+        _ => return None,
+    })
+}