feat(keybindings): add mouse button support for mpv keybindings (#103)

src/renderer/handlers/keyboard.test.ts

@@ -322,18 +322,31 @@ function installKeyboardTestGlobals() {
     }
   }
 
-  function dispatchDocumentMouseDown(event: { button: number; target?: unknown }): void {
+  function dispatchMousedown(event: {
+    button: number;
+    ctrlKey?: boolean;
+    metaKey?: boolean;
+    altKey?: boolean;
+    shiftKey?: boolean;
+    target?: unknown;
+  }): void {
     const listeners = documentListeners.get('mousedown') ?? [];
     const mouseEvent = {
       button: event.button,
-      target: event.target ?? null,
+      ctrlKey: event.ctrlKey ?? false,
+      metaKey: event.metaKey ?? false,
+      altKey: event.altKey ?? false,
+      shiftKey: event.shiftKey ?? false,
       preventDefault: () => {},
+      target: event.target ?? null,
     };
     for (const listener of listeners) {
       listener(mouseEvent);
     }
   }
 
+  const dispatchDocumentMouseDown = dispatchMousedown;
+
   function dispatchFocusInOnPopup(): void {
     const listeners = documentListeners.get('focusin') ?? [];
     const focusEvent = {
@@ -389,6 +402,7 @@ function installKeyboardTestGlobals() {
     windowFocusCalls: () => windowFocusCalls,
     dispatchKeydown,
     dispatchDocumentMouseDown,
+    dispatchMousedown,
     dispatchFocusInOnPopup,
     dispatchWindowEvent,
     setPopupVisible: (value: boolean) => {
@@ -1036,6 +1050,31 @@ test('paused configured subtitle-jump keybinding re-applies pause after backward
   }
 });
 
+test('configured mouse button keybinding dispatches through overlay mouse handling', async () => {
+  const { handlers, testGlobals } = createKeyboardHandlerHarness();
+
+  try {
+    await handlers.setupMpvInputForwarding();
+    handlers.updateSessionBindings([
+      {
+        sourcePath: 'keybindings[0].key',
+        originalKey: 'MBTN_BACK',
+        key: { code: 'MBTN_BACK', modifiers: [] },
+        actionType: 'mpv-command',
+        command: ['sub-seek', -1],
+      },
+    ] as never);
+    testGlobals.setPlaybackPausedResponse(false);
+
+    testGlobals.dispatchMousedown({ button: 3 });
+    await wait(0);
+
+    assert.deepEqual(testGlobals.mpvCommands.slice(-1), [['sub-seek', -1]]);
+  } finally {
+    testGlobals.restore();
+  }
+});
+
 test('configured subtitle-jump keybinding preserves pause when pause state is unknown', async () => {
   const { handlers, testGlobals } = createKeyboardHandlerHarness();
 

src/renderer/handlers/keyboard.ts

@@ -37,6 +37,13 @@ export function createKeyboardHandlers(
   const CHORD_TIMEOUT_MS = 1000;
   const MPV_INPUT_FORWARDING_CONFIG_LOAD_TIMEOUT_MS = 50;
   const KEYBOARD_SELECTED_WORD_CLASS = 'keyboard-selected';
+  const MOUSE_BUTTON_CODE_BY_BUTTON: Record<number, string> = {
+    0: 'MBTN_LEFT',
+    1: 'MBTN_MID',
+    2: 'MBTN_RIGHT',
+    3: 'MBTN_BACK',
+    4: 'MBTN_FORWARD',
+  };
   let pendingSelectionAnchorAfterSubtitleSeek: 'start' | 'end' | null = null;
   let pendingLookupRefreshAfterSubtitleSeek = false;
   let resetSelectionToStartOnNextSubtitleSync = false;
@@ -81,6 +88,19 @@ export function createKeyboardHandlers(
     return parts.join('+');
   }
 
+  function mouseEventToString(e: MouseEvent): string | null {
+    const code = MOUSE_BUTTON_CODE_BY_BUTTON[e.button];
+    if (!code) return null;
+
+    const parts: string[] = [];
+    if (e.ctrlKey) parts.push('Ctrl');
+    if (e.altKey) parts.push('Alt');
+    if (e.shiftKey) parts.push('Shift');
+    if (e.metaKey) parts.push('Meta');
+    parts.push(code);
+    return parts.join('+');
+  }
+
   function updateConfiguredShortcuts(
     shortcuts: Required<ShortcutsConfig>,
     statsToggleKey?: string,
@@ -1216,6 +1236,14 @@ export function createKeyboardHandlers(
     });
 
     document.addEventListener('mousedown', (e: MouseEvent) => {
+      const mouseString = mouseEventToString(e);
+      const binding = mouseString ? ctx.state.sessionBindingMap.get(mouseString) : undefined;
+      if (binding) {
+        e.preventDefault();
+        dispatchSessionBinding(binding);
+        return;
+      }
+
       if (e.button === 2 && !isInteractiveTarget(e.target)) {
         e.preventDefault();
         void window.electronAPI

src/renderer/modals/session-help-sections.ts

@@ -57,6 +57,11 @@ const KEY_NAME_MAP: Record<string, string> = {
   Super: 'Meta',
   Meta: 'Meta',
   Backspace: 'Backspace',
+  MBTN_LEFT: 'Mouse Left',
+  MBTN_MID: 'Mouse Middle',
+  MBTN_RIGHT: 'Mouse Right',
+  MBTN_BACK: 'Mouse Back',
+  MBTN_FORWARD: 'Mouse Forward',
 };
 
 function normalizeKeyToken(token: string): string {