feat(plugins): add JavaScript plugin system with overlay panel (#303)

src/core/services/mpv-protocol.ts

@@ -1,6 +1,7 @@
 import { MpvSubtitleRenderMetrics } from '../../types';
 import { sanitizeMediaTitle } from '../../shared/media-identity';
 import { widenHalfwidthKana } from '../utils/halfwidth-kana';
+import type { PluginMpvEventMap } from '../../plugin-api';
 import { toVideoClock } from './subtitle-clock';
 
 export type MpvMessage = {
@@ -10,8 +11,26 @@ export type MpvMessage = {
   args?: unknown;
   request_id?: number;
   error?: string;
+  reason?: unknown;
+  playlist_entry_id?: unknown;
+  file_error?: unknown;
 };
 
+const MPV_END_FILE_REASONS = ['eof', 'stop', 'quit', 'error', 'redirect'] as const;
+export type MpvEndFileReason = PluginMpvEventMap['end-file']['reason'];
+
+/** mpv's `end-file` event: why the current file stopped, and mpv's error text when it failed. */
+export type MpvEndFileEvent = PluginMpvEventMap['end-file'];
+
+function parseEndFileEvent(msg: MpvMessage): MpvEndFileEvent {
+  const reason = MPV_END_FILE_REASONS.find((known) => known === msg.reason) ?? 'unknown';
+  return {
+    reason,
+    playlistEntryId: typeof msg.playlist_entry_id === 'number' ? msg.playlist_entry_id : null,
+    error: typeof msg.file_error === 'string' && msg.file_error ? msg.file_error : null,
+  };
+}
+
 export const MPV_REQUEST_ID_SUBTEXT = 101;
 export const MPV_REQUEST_ID_PATH = 102;
 export const MPV_REQUEST_ID_SECONDARY_SUBTEXT = 103;
@@ -103,6 +122,8 @@ export interface MpvProtocolHandleMessageDeps {
   shouldQuitOnMpvShutdown: () => boolean;
   requestAppQuit: () => void;
   emitClientMessage?: (payload: { args: string[] }) => void;
+  emitEndFile?: (payload: MpvEndFileEvent) => void;
+  emitFileLoaded?: () => void;
 }
 
 type SubtitleTrackCandidate = {
@@ -433,6 +454,10 @@ export async function dispatchMpvProtocolMessage(
     if (args.length > 0) {
       deps.emitClientMessage?.({ args });
     }
+  } else if (msg.event === 'file-loaded') {
+    deps.emitFileLoaded?.();
+  } else if (msg.event === 'end-file') {
+    deps.emitEndFile?.(parseEndFileEvent(msg));
   } else if (msg.event === 'shutdown') {
     deps.restorePreviousSecondarySubVisibility();
     if (deps.shouldQuitOnMpvShutdown()) {