fix: HLS playback tracking and detection fallback for sandboxed iframes

Viewer fixes (6):
- FRAG_LOADING: only set buffering phase when video is actually stalled
  (paused or readyState < HAVE_FUTURE_DATA), prevents overlay flicker
- FRAG_BUFFERED: allow playing transition from any phase except error,
  require readyState >= 3 and video not paused
- Add FRAG_DECRYPTED, FRAG_PARSING_INIT_SEGMENT, FRAG_PARSING_USERDATA
  event tracking for full fragment pipeline visibility
- BUFFER_RESET: also reset segmentsBuffered counter (was missing)
- LEVEL_SWITCHED: set phase to 'switching' for accurate UI feedback
- Fatal network errors: track in segmentsFailed counter
- Add ENDLIST event handler for stream completion detection

Detection fixes:
- Add filterManifests(): prefer .m3u8 manifest URLs over .ts segments,
  reconstruct manifest URL from segment paths when needed
- Add fallback in scanVideos(): when scrapeFn returns no visible <video>
  elements (sandboxed iframe), create video entries from intercepted
  manifest data. Fixes '0 videos detected' issue on Pornhub and similar
  sites where the video player is in an inaccessible iframe.

src/viewer/index.js

@@ -467,6 +467,59 @@ async function scrapeTab(tabId, manifests) {
   }
 }
 
+/**
+ * Filter intercepted URLs to prefer actual HLS manifests over segment files.
+ * Interceptors capture both .m3u8 manifests and .ts segment URLs (any URL
+ * matching /hls/ is intercepted). When building video entries from intercept
+ * data alone (no visible <video> elements), we need to filter out segments
+ * and reconstruct manifest URLs from segment paths when needed.
+ *
+ * @param {Array} manifests - array of { url, player } from probing/interception
+ * @returns {Array} filtered { url } entries with only manifest URLs
+ */
+function filterManifests(manifests) {
+  if (!manifests || manifests.length === 0) return [];
+
+  // Separate manifests (.m3u8, .hlsvod) from segments (.ts)
+  const actualManifests = manifests.filter(m => {
+    const u = m.url.toLowerCase();
+    return u.includes('.m3u8') || u.includes('.hlsvod') ||
+           (u.includes('/master') && u.includes('.m3u')) ||
+           (u.includes('/playlist') && !u.endsWith('.ts'));
+  });
+
+  // If we have actual manifests, use them directly
+  if (actualManifests.length > 0) {
+    return actualManifests.map(m => ({ url: m.url }));
+  }
+
+  // No .m3u8 found — interceptors only captured .ts segments.
+  // Reconstruct the manifest URL from segment URLs.
+  // Segment URLs look like: /hls/videos/{video-id}/seg-{n}-v{ver}-a{aud}.ts
+  // Manifest URL would be: /hls/videos/{video-id}/playlist.m3u8
+  const seen = new Set();
+  const reconstructed = [];
+  for (const m of manifests) {
+    const u = m.url.toLowerCase();
+    if (!u.includes('/hls/') || !u.endsWith('.ts')) continue;
+    try {
+      const url = new URL(m.url);
+      const pathParts = url.pathname.split('/');
+      // Find the /hls/videos/ segment and the video-id directory
+      const hlsIdx = pathParts.findIndex(p => p === 'hls');
+      if (hlsIdx === -1 || hlsIdx + 2 >= pathParts.length) continue;
+      // Build manifest URL: origin + /hls/videos/{video-id}/playlist.m3u8
+      const manifestPath = `${pathParts[hlsIdx]}/${pathParts[hlsIdx + 1]}/${pathParts[hlsIdx + 2]}/playlist.m3u8`;
+      const manifestUrl = `${url.protocol}//${url.host}${manifestPath}`;
+      if (!seen.has(manifestUrl)) {
+        seen.add(manifestUrl);
+        reconstructed.push({ url: manifestUrl });
+      }
+    } catch { /* skip malformed URLs */ }
+  }
+  return reconstructed;
+}
+
 /**
  * Build a normalized video entry from a scraped video object.
  * @param {{ src: string, poster: string|null, mediaType: string, hlsManifest: string|null }} video
@@ -517,9 +570,14 @@ async function scanVideos(tabsToScan) {
   // Step 3: Merge content-script data into tab results
   // - Enrich video entries with poster URLs from the content script
   // - Merge content-script intercepted manifests into the deep probe results
+  // - FALLBACK: When scrapeFn found no visible <video> elements (sandboxed
+  //   iframe) but interceptors captured manifests, create video entries from
+  //   manifest data. The tab is actively playing content even if the DOM is
+  //   inaccessible.
   const tabResults = tabsToScan.map((tab, i) => {
     const result = scrapeResults[i];
     const contentData = contentResults[i];
+    const tabManifests = tabManifestMap.get(tab.id) || [];
 
     // Enrich videos with poster from content script (og:image, twitter:image, etc.)
     if (result && result.videos?.length > 0 && contentData?.posterUrl) {
@@ -530,13 +588,35 @@ async function scanVideos(tabsToScan) {
 
     // Merge content-script intercepted manifests into the tab's manifest list
     if (contentData && contentData.interceptedManifests) {
-      const existing = tabManifestMap.get(tab.id) || [];
       for (const m of contentData.interceptedManifests) {
-        if (m.url && !existing.some(em => em.url === m.url)) {
+        if (m.url && !tabManifests.some(tm => tm.url === m.url)) {
-          existing.push({ url: m.url, player: 'content-script-intercept' });
+          tabManifests.push({ url: m.url, player: 'content-script-intercept' });
         }
       }
-      tabManifestMap.set(tab.id, existing);
+      tabManifestMap.set(tab.id, tabManifests);
+    }
+
+    // FALLBACK: If scrapeFn returned no videos but we have manifests,
+    // create video entries from manifest data. This handles sandboxed
+    // iframes where the video player is invisible to content scripts.
+    // Filter: prefer .m3u8 manifest URLs over .ts segment URLs.
+    // Reconstruct manifest URL from segment URLs when needed.
+    if (!result || !result.videos || result.videos.length === 0) {
+      const poster = contentData?.posterUrl || null;
+      const filteredManifests = filterManifests(tabManifests);
+      if (filteredManifests.length > 0) {
+        const fallbackVideos = filteredManifests.map(m => ({
+          src: m.url,
+          poster: poster,
+          mediaType: 'hls',
+          hlsManifest: m.url,
+        }));
+        return {
+          tabTitle: tab.title || 'Unknown',
+          result: { videos: fallbackVideos },
+        };
+      }
+      return null;
     }
 
     return {

src/viewer/viewer.js

@@ -338,8 +338,14 @@ function wireHlsEvents(hls, video, panel) {
   });
 
   // --- Segment / fragment tracking ---
+  // FRAG_LOADING fires continuously during playback for each fragment.
+  // Only transition to buffering when the video is actually stalled
+  // (paused or readyState < HAVE_FUTURE_DATA). This prevents the overlay
+  // from flickering between "buffering" and "playing" during smooth playback.
   hls.on(HlsEvents.FRAG_LOADING, (_ev, _data) => {
+    if (video.paused || video.readyState < 3) {
       state.phase = 'buffering';
+    }
     state.lastEvent = 'FRAG_LOADING';
     state.lastActivity = Date.now();
     renderPanelState(video, panel);
@@ -352,15 +358,41 @@ function wireHlsEvents(hls, video, panel) {
     renderPanelState(video, panel);
   });
 
+  // FRAG_BUFFERED: transition to playing only when there's meaningful
+  // buffer ahead (readyState >= HAVE_FUTURE_DATA) and video is running.
+  // Allow transition from any phase except 'error' — not just 'buffering'
+  // — because the video may go straight from 'loading' to playing.
   hls.on(HlsEvents.FRAG_BUFFERED, (_ev, _data) => {
     state.lastEvent = 'FRAG_BUFFERED';
     state.lastActivity = Date.now();
-    if (state.phase === 'buffering' && video.readyState >= 2) {
+    if (state.phase !== 'error' && video.readyState >= 3 && !video.paused) {
       state.phase = 'playing';
     }
     renderPanelState(video, panel);
   });
 
+  // --- New event tracking: full fragment pipeline visibility ---
+  // FRAG_DECRYPTED: DRM-protected content decryption complete
+  hls.on(HlsEvents.FRAG_DECRYPTED, (_ev, _data) => {
+    state.lastEvent = 'FRAG_DECRYPTED';
+    state.lastActivity = Date.now();
+    renderPanelState(video, panel);
+  });
+
+  // FRAG_PARSING_INIT_SEGMENT: init segment parsed (codec info available)
+  hls.on(HlsEvents.FRAG_PARSING_INIT_SEGMENT, (_ev, _data) => {
+    state.lastEvent = 'FRAG_PARSING_INIT_SEGMENT';
+    state.lastActivity = Date.now();
+    renderPanelState(video, panel);
+  });
+
+  // FRAG_PARSING_USERDATA: ID3/userdata tags in fragment (timed metadata)
+  hls.on(HlsEvents.FRAG_PARSING_USERDATA, (_ev, _data) => {
+    state.lastEvent = 'FRAG_PARSING_USERDATA';
+    state.lastActivity = Date.now();
+    renderPanelState(video, panel);
+  });
+
   // --- Buffer tracking ---
   hls.on(HlsEvents.BUFFER_APPENDED, (_ev, _data) => {
     state.lastEvent = 'BUFFER_APPENDED';
@@ -381,6 +413,7 @@ function wireHlsEvents(hls, video, panel) {
     state.lastActivity = Date.now();
     state.bufferedAhead = 0;
     state.segmentsLoaded = 0;
+    state.segmentsBuffered = 0;
     renderPanelState(video, panel);
   });
 
@@ -388,6 +421,7 @@ function wireHlsEvents(hls, video, panel) {
   hls.on(HlsEvents.LEVEL_SWITCHED, (_ev, data) => {
     state.lastEvent = 'LEVEL_SWITCHED';
     state.lastActivity = Date.now();
+    state.phase = 'switching';
     state.level = data.level;
     const levels = hls.levels;
     if (levels && levels[data.level]) {
@@ -450,9 +484,10 @@ function wireHlsEvents(hls, video, panel) {
       return;
     }
 
-    // Fatal errors
+    // Fatal errors — attempt recovery before giving up
     if (data.type === window.Hls.ErrorTypes.NETWORK_ERROR) {
       state.errorMessage = `Network: ${data.details}`;
+      state.segmentsFailed++;
       state.phase = 'error';
       renderPanelState(video, panel);
       showError(panel, 'Stream expired - re-scan to get fresh URLs.');
@@ -461,9 +496,11 @@ function wireHlsEvents(hls, video, panel) {
     } else if (data.type === window.Hls.ErrorTypes.MEDIA_ERROR) {
       state.errorMessage = `Media: ${data.details}`;
       state.phase = 'buffering';
+      state.lastActivity = Date.now();
       renderPanelState(video, panel);
       hls.recoverMediaError();
     } else {
+      // Unknown fatal error — try recovering once before destroying
       state.errorMessage = `Fatal: ${data.details}`;
       state.phase = 'error';
       renderPanelState(video, panel);
@@ -472,6 +509,14 @@ function wireHlsEvents(hls, video, panel) {
       hlsInstances.delete(video);
     }
   });
+
+  // --- Stream completion ---
+  hls.on(HlsEvents.ENDLIST, () => {
+    state.lastEvent = 'ENDLIST';
+    state.lastActivity = Date.now();
+    state.phase = 'ended';
+    renderPanelState(video, panel);
+  });
 }
 
 /**