Add support for functional key codes from kitty keyboard protocol

examples/event-match-modifiers.rs

@@ -45,29 +45,24 @@ fn match_event(read_event: Event) {
 }
 
 fn main() {
-    match_event(Event::Key(KeyEvent {
-        modifiers: KeyModifiers::CONTROL,
-        code: KeyCode::Char('z'),
-        kind: KeyEventKind::Press,
-    }));
-    match_event(Event::Key(KeyEvent {
-        modifiers: KeyModifiers::SHIFT,
-        code: KeyCode::Left,
-        kind: KeyEventKind::Press,
-    }));
-    match_event(Event::Key(KeyEvent {
-        modifiers: KeyModifiers::ALT,
-        code: KeyCode::Delete,
-        kind: KeyEventKind::Press,
-    }));
-    match_event(Event::Key(KeyEvent {
-        modifiers: KeyModifiers::ALT | KeyModifiers::SHIFT,
-        code: KeyCode::Right,
-        kind: KeyEventKind::Press,
-    }));
-    match_event(Event::Key(KeyEvent {
-        modifiers: KeyModifiers::ALT | KeyModifiers::CONTROL,
-        code: KeyCode::Home,
-        kind: KeyEventKind::Press,
-    }));
+    match_event(Event::Key(KeyEvent::new(
+        KeyCode::Char('z'),
+        KeyModifiers::CONTROL,
+    )));
+    match_event(Event::Key(KeyEvent::new(
+        KeyCode::Left,
+        KeyModifiers::SHIFT,
+    )));
+    match_event(Event::Key(KeyEvent::new(
+        KeyCode::Delete,
+        KeyModifiers::ALT,
+    )));
+    match_event(Event::Key(KeyEvent::new(
+        KeyCode::Right,
+        KeyModifiers::ALT | KeyModifiers::SHIFT,
+    )));
+    match_event(Event::Key(KeyEvent::new(
+        KeyCode::Home,
+        KeyModifiers::ALT | KeyModifiers::CONTROL,
+    )));
 }

src/event.rs

@@ -377,7 +377,7 @@ impl Command for PushKeyboardEnhancementFlags {
     fn execute_winapi(&self) -> Result<()> {
         Err(io::Error::new(
             io::ErrorKind::Unsupported,
-            "Keyboard progressive enhancement not implemented on Windows.",
+            "Keyboard progressive enhancement not implemented for the legacy Windows API.",
         ))
     }
 
@@ -404,7 +404,7 @@ impl Command for PopKeyboardEnhancementFlags {
     fn execute_winapi(&self) -> Result<()> {
         Err(io::Error::new(
             io::ErrorKind::Unsupported,
-            "Keyboard progressive enhancement not implemented on Windows.",
+            "Keyboard progressive enhancement not implemented for the legacy Windows API.",
         ))
     }
 
@@ -553,6 +553,15 @@ pub enum KeyEventKind {
     Release,
 }
 
+bitflags! {
+    /// Represents extra state about the key event.
+    #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+    pub struct KeyEventState: u8 {
+        /// The key event origins from the keypad.
+        const KEYPAD = 0b0000_0001;
+    }
+}
+
 /// Represents a key event.
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 #[derive(Debug, PartialOrd, Clone, Copy)]
@@ -563,6 +572,11 @@ pub struct KeyEvent {
     pub modifiers: KeyModifiers,
     /// Kind of event.
     pub kind: KeyEventKind,
+    /// Keyboard state.
+    ///
+    /// Only set if [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] has been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    pub state: KeyEventState,
 }
 
 impl KeyEvent {
@@ -571,6 +585,7 @@ impl KeyEvent {
             code,
             modifiers,
             kind: KeyEventKind::Press,
+            state: KeyEventState::empty(),
         }
     }
 
@@ -583,6 +598,21 @@ impl KeyEvent {
             code,
             modifiers,
             kind,
+            state: KeyEventState::empty(),
+        }
+    }
+
+    pub const fn new_with_kind_and_state(
+        code: KeyCode,
+        modifiers: KeyModifiers,
+        kind: KeyEventKind,
+        state: KeyEventState,
+    ) -> KeyEvent {
+        KeyEvent {
+            code,
+            modifiers,
+            kind,
+            state,
         }
     }
 
@@ -610,6 +640,7 @@ impl From<KeyCode> for KeyEvent {
             code,
             modifiers: KeyModifiers::empty(),
             kind: KeyEventKind::Press,
+            state: KeyEventState::empty(),
         }
     }
 }
@@ -620,31 +651,104 @@ impl PartialEq for KeyEvent {
             code: lhs_code,
             modifiers: lhs_modifiers,
             kind: lhs_kind,
+            state: lhs_state,
         } = self.normalize_case();
         let KeyEvent {
             code: rhs_code,
             modifiers: rhs_modifiers,
             kind: rhs_kind,
+            state: rhs_state,
         } = other.normalize_case();
-        (lhs_code == rhs_code) && (lhs_modifiers == rhs_modifiers) && (lhs_kind == rhs_kind)
+        (lhs_code == rhs_code)
+            && (lhs_modifiers == rhs_modifiers)
+            && (lhs_kind == rhs_kind)
+            && (lhs_state == rhs_state)
     }
 }
 
 impl Eq for KeyEvent {}
 
 impl Hash for KeyEvent {
-    fn hash<H: Hasher>(&self, state: &mut H) {
+    fn hash<H: Hasher>(&self, hash_state: &mut H) {
         let KeyEvent {
             code,
             modifiers,
             kind,
+            state,
         } = self.normalize_case();
-        code.hash(state);
-        modifiers.hash(state);
-        kind.hash(state);
+        code.hash(hash_state);
+        modifiers.hash(hash_state);
+        kind.hash(hash_state);
+        state.hash(hash_state);
     }
 }
 
+/// Represents a media key (as part of [`KeyCode::Media`]).
+#[derive(Debug, PartialOrd, PartialEq, Eq, Clone, Copy, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub enum MediaKeyCode {
+    /// Play media key.
+    Play,
+    /// Pause media key.
+    Pause,
+    /// Play/Pause media key.
+    PlayPause,
+    /// Reverse media key.
+    Reverse,
+    /// Stop media key.
+    Stop,
+    /// Fast-forward media key.
+    FastForward,
+    /// Rewind media key.
+    Rewind,
+    /// Next-track media key.
+    TrackNext,
+    /// Previous-track media key.
+    TrackPrevious,
+    /// Record media key.
+    Record,
+    /// Lower-volume media key.
+    LowerVolume,
+    /// Raise-volume media key.
+    RaiseVolume,
+    /// Mute media key.
+    MuteVolume,
+}
+
+/// Represents a modifier key (as part of [`KeyCode::Modifier`]).
+#[derive(Debug, PartialOrd, PartialEq, Eq, Clone, Copy, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub enum ModifierKeyCode {
+    /// Left Shift key.
+    LeftShift,
+    /// Left Control key.
+    LeftControl,
+    /// Left Alt key.
+    LeftAlt,
+    /// Left Super key.
+    LeftSuper,
+    /// Left Hyper key.
+    LeftHyper,
+    /// Left Meta key.
+    LeftMeta,
+    /// Right Shift key.
+    RightShift,
+    /// Right Control key.
+    RightControl,
+    /// Right Alt key.
+    RightAlt,
+    /// Right Super key.
+    RightSuper,
+    /// Right Hyper key.
+    RightHyper,
+    /// Right Meta key.
+    RightMeta,
+    /// Iso Level3 Shift key.
+    IsoLevel3Shift,
+    /// Iso Level5 Shift key.
+    IsoLevel5Shift,
+}
+
 /// Represents a key.
 #[derive(Debug, PartialOrd, PartialEq, Eq, Clone, Copy, Hash)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
@@ -689,6 +793,61 @@ pub enum KeyCode {
     Null,
     /// Escape key.
     Esc,
+    /// Caps Lock key.
+    ///
+    /// **Note:** this key can only be read if
+    /// [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] has been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    CapsLock,
+    /// Scroll Lock key.
+    ///
+    /// **Note:** this key can only be read if
+    /// [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] has been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    ScrollLock,
+    /// Num Lock key.
+    ///
+    /// **Note:** this key can only be read if
+    /// [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] has been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    NumLock,
+    /// Print Screen key.
+    ///
+    /// **Note:** this key can only be read if
+    /// [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] has been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    PrintScreen,
+    /// Pause key.
+    ///
+    /// **Note:** this key can only be read if
+    /// [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] has been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    Pause,
+    /// Menu key.
+    ///
+    /// **Note:** this key can only be read if
+    /// [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] has been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    Menu,
+    /// The "Begin" key (often mapped to the 5 key when Num Lock is turned on).
+    ///
+    /// **Note:** this key can only be read if
+    /// [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] has been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    KeypadBegin,
+    /// A media key.
+    ///
+    /// **Note:** these keys can only be read if
+    /// [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] has been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    Media(MediaKeyCode),
+    /// A modifier key.
+    ///
+    /// **Note:** these keys can only be read if **both**
+    /// [`KeyboardEnhancementFlags::DISAMBIGUATE_ESCAPE_CODES`] and
+    /// [`KeyboardEnhancementFlags::REPORT_ALL_KEYS_AS_ESCAPE_CODES`] have been enabled with
+    /// [`PushKeyboardEnhancementFlags`].
+    Modifier(ModifierKeyCode),
 }
 
 /// An internal event.