fix(subtitles): recover canonical lines from ASS animation (#207)

src/main/runtime/mpv-main-event-main-deps.ts

@@ -1,5 +1,11 @@
 import { createSubtitleLineDedupGate } from '../../core/services/subtitle-line-dedup-gate';
 import type { MergedToken, SubtitleCue, SubtitleData } from '../../types';
+import { SEEK_LIKE_TIME_DELTA_SECONDS } from './mpv-main-event-actions';
+import {
+  resolveCanonicalPrimarySubtitle,
+  resolvePrimarySubtitleText,
+  stripCanonicalFragmentLines,
+} from './primary-subtitle-text';
 
 type AnilistPostWatchRunOptions = {
   watchedSeconds?: number;
@@ -36,6 +42,8 @@ export function createBuildBindMpvMainEventHandlersMainDepsHandler(deps: {
       recordSubtitle?: (text: string, start: number, end: number, secondaryText?: string) => void;
     } | null;
     activeParsedSubtitleCues?: SubtitleCue[] | null;
+    /** Cache key of the source the cues were parsed from; cleared with the cues. */
+    activeParsedSubtitleSource?: string | null;
     currentMediaPath?: string | null;
     currentSubText: string;
     currentSubAssText: string;
@@ -93,6 +101,38 @@ export function createBuildBindMpvMainEventHandlersMainDepsHandler(deps: {
   const immersionLineDedupGate = createSubtitleLineDedupGate({
     getParsedCues: () => deps.appState.activeParsedSubtitleCues,
   });
+  // One seen-set per consumer: canonical cues overlap, so live samples resolve to
+  // shifting subsets (A, then A+B, then B). Remembering every recorded cue -- not just
+  // the previous sample -- keeps each authored line recorded exactly once per source.
+  const recordedImmersionCanonicalKeys = new Set<string>();
+  const recordedTimingCanonicalKeys = new Set<string>();
+  // Bumped on track/media changes so an immersion record whose tokenization resolves
+  // after the change is dropped instead of landing in the next session.
+  let subtitleSessionEpoch = 0;
+  let lastTimePosForTimingReset: number | null = null;
+  const canonicalCueKey = (cue: SubtitleCue): string =>
+    `${cue.startTime}|${cue.endTime}|${cue.text}`;
+  const resetSubtitleDeduplication = (): void => {
+    immersionLineDedupGate.reset();
+    recordedImmersionCanonicalKeys.clear();
+    recordedTimingCanonicalKeys.clear();
+    subtitleSessionEpoch += 1;
+    lastTimePosForTimingReset = null;
+  };
+  const resolveCanonicalSample = (liveText: string, startSec: number) =>
+    resolveCanonicalPrimarySubtitle({
+      liveText,
+      currentTimeSec: startSec,
+      cues: deps.appState.activeParsedSubtitleCues,
+    });
+  // When substitution declined because dialogue shares the screen with a song, record
+  // the dialogue alone rather than the combined dialogue-plus-fragments stack.
+  const stripFragmentsForRecording = (liveText: string, startSec: number) =>
+    stripCanonicalFragmentLines({
+      liveText,
+      currentTimeSec: startSec,
+      cues: deps.appState.activeParsedSubtitleCues,
+    });
   const hasInitialPlaybackQuitOnDisconnectArg = (): boolean =>
     Boolean(
       deps.appState.initialArgs?.managedPlayback ||
@@ -111,45 +151,99 @@ export function createBuildBindMpvMainEventHandlersMainDepsHandler(deps: {
     scheduleQuitCheck: (callback: () => void) => deps.scheduleQuitCheck(callback),
     isMpvConnected: () => Boolean(deps.appState.mpvClient?.connected),
     quitApp: () => deps.quitApp(),
+    resolveSubtitleText: (liveText: string) =>
+      resolvePrimarySubtitleText({
+        liveText,
+        currentTimeSec: Number(deps.appState.mpvClient?.currentTimePos),
+        cues: deps.appState.activeParsedSubtitleCues,
+      }),
     recordImmersionSubtitleLine: (text: string, start: number, end: number) => {
       deps.ensureImmersionTrackerInitialized();
       const tracker = deps.appState.immersionTracker;
       if (!tracker?.recordSubtitleLine) {
         return;
       }
+      const recordLine = (lineText: string, startSec: number, endSec: number): void => {
+        const secondaryText = deps.appState.mpvClient?.currentSecondarySubText || null;
+        const cachedTokens =
+          deps.appState.currentSubtitleData?.text === lineText
+            ? deps.appState.currentSubtitleData.tokens
+            : null;
+        if (cachedTokens) {
+          tracker.recordSubtitleLine?.(lineText, startSec, endSec, cachedTokens, secondaryText);
+          return;
+        }
+        if (!deps.tokenizeSubtitleForImmersion) {
+          tracker.recordSubtitleLine?.(lineText, startSec, endSec, null, secondaryText);
+          return;
+        }
+        const epochAtRecord = subtitleSessionEpoch;
+        void deps
+          .tokenizeSubtitleForImmersion(lineText)
+          .then((payload) => {
+            if (subtitleSessionEpoch !== epochAtRecord) {
+              return;
+            }
+            tracker.recordSubtitleLine?.(
+              lineText,
+              startSec,
+              endSec,
+              payload?.tokens ?? null,
+              secondaryText,
+            );
+          })
+          .catch(() => {
+            if (subtitleSessionEpoch !== epochAtRecord) {
+              return;
+            }
+            tracker.recordSubtitleLine?.(lineText, startSec, endSec, null, secondaryText);
+          });
+      };
+      const canonical = resolveCanonicalSample(text, start);
+      if (canonical) {
+        for (const cue of canonical.cues) {
+          const key = canonicalCueKey(cue);
+          if (recordedImmersionCanonicalKeys.has(key)) {
+            continue;
+          }
+          recordedImmersionCanonicalKeys.add(key);
+          recordLine(cue.text, cue.startTime, cue.endTime);
+        }
+        return;
+      }
+      text = stripFragmentsForRecording(text, start);
       if (!immersionLineDedupGate.shouldRecord({ text, startSec: start, endSec: end })) {
         return;
       }
-      const secondaryText = deps.appState.mpvClient?.currentSecondarySubText || null;
-      const cachedTokens =
-        deps.appState.currentSubtitleData?.text === text
-          ? deps.appState.currentSubtitleData.tokens
-          : null;
-      if (cachedTokens) {
-        tracker.recordSubtitleLine(text, start, end, cachedTokens, secondaryText);
-        return;
-      }
-      if (!deps.tokenizeSubtitleForImmersion) {
-        tracker.recordSubtitleLine(text, start, end, null, secondaryText);
-        return;
-      }
-      void deps
-        .tokenizeSubtitleForImmersion(text)
-        .then((payload) => {
-          tracker.recordSubtitleLine?.(text, start, end, payload?.tokens ?? null, secondaryText);
-        })
-        .catch(() => {
-          tracker.recordSubtitleLine?.(text, start, end, null, secondaryText);
-        });
+      recordLine(text, start, end);
     },
     hasSubtitleTimingTracker: () => Boolean(deps.appState.subtitleTimingTracker),
-    recordSubtitleTiming: (text: string, start: number, end: number) =>
-      deps.appState.subtitleTimingTracker?.recordSubtitle?.(
-        text,
-        start,
-        end,
-        deps.appState.mpvClient?.currentSecondarySubText || undefined,
-      ),
+    recordSubtitleTiming: (text: string, start: number, end: number) => {
+      const secondaryText = deps.appState.mpvClient?.currentSecondarySubText || undefined;
+      const canonical = resolveCanonicalSample(text, start);
+      if (!canonical) {
+        deps.appState.subtitleTimingTracker?.recordSubtitle?.(
+          stripFragmentsForRecording(text, start),
+          start,
+          end,
+          secondaryText,
+        );
+        return;
+      }
+      for (const cue of canonical.cues) {
+        const key = canonicalCueKey(cue);
+        if (recordedTimingCanonicalKeys.has(key)) {
+          continue;
+        }
+        recordedTimingCanonicalKeys.add(key);
+        deps.appState.subtitleTimingTracker?.recordSubtitle?.(
+          cue.text,
+          cue.startTime,
+          cue.endTime,
+          secondaryText,
+        );
+      }
+    },
     maybeRunAnilistPostWatchUpdate: (options?: AnilistPostWatchRunOptions) =>
       deps.maybeRunAnilistPostWatchUpdate(options),
     logSubtitleTimingError: (message: string, error: unknown) =>
@@ -170,7 +264,14 @@ export function createBuildBindMpvMainEventHandlersMainDepsHandler(deps: {
       ? (message: string) => deps.logSubtitleProcessingDebug!(message)
       : undefined,
     onSubtitleTrackChange: (sid: number | null) => {
-      immersionLineDedupGate.reset();
+      resetSubtitleDeduplication();
+      // The replacement track's cues arrive only after an async re-read and re-parse.
+      // Clearing synchronously keeps the previous track's canonical cues from
+      // substituting into, or recording against, the new track's live text. The source
+      // key is cleared with the cues so cue-list consumers (the sidebar snapshot)
+      // re-parse on demand instead of trusting the stale pairing.
+      deps.appState.activeParsedSubtitleCues = [];
+      deps.appState.activeParsedSubtitleSource = null;
       deps.onSubtitleTrackChange?.(sid);
     },
     onSubtitleTrackListChange: deps.onSubtitleTrackListChange
@@ -185,7 +286,7 @@ export function createBuildBindMpvMainEventHandlersMainDepsHandler(deps: {
     broadcastSecondarySubtitle: (text: string) =>
       deps.broadcastToOverlayWindows('secondary-subtitle:set', text),
     updateCurrentMediaPath: (path: string) => {
-      immersionLineDedupGate.reset();
+      resetSubtitleDeduplication();
       deps.updateCurrentMediaPath(path);
     },
     restoreMpvSubVisibility: () => deps.restoreMpvSubVisibility(),
@@ -217,9 +318,22 @@ export function createBuildBindMpvMainEventHandlersMainDepsHandler(deps: {
     },
     reportJellyfinRemoteProgress: (forceImmediate: boolean) =>
       deps.reportJellyfinRemoteProgress(forceImmediate),
-    onTimePosUpdate: deps.onTimePosUpdate
-      ? (time: number) => deps.onTimePosUpdate!(time)
-      : undefined,
+    onTimePosUpdate: (time: number) => {
+      // Timing history is a viewing log: after a real backward seek, a rewatched
+      // canonical line should enter it again. Immersion stats keep their
+      // once-per-media deduplication and are not reset here.
+      if (
+        Number.isFinite(time) &&
+        lastTimePosForTimingReset !== null &&
+        time <= lastTimePosForTimingReset - SEEK_LIKE_TIME_DELTA_SECONDS
+      ) {
+        recordedTimingCanonicalKeys.clear();
+      }
+      if (Number.isFinite(time)) {
+        lastTimePosForTimingReset = time;
+      }
+      deps.onTimePosUpdate?.(time);
+    },
     onFullscreenChange: deps.onFullscreenChange
       ? (fullscreen: boolean) => deps.onFullscreenChange!(fullscreen)
       : undefined,