v10: Fix DVR — stream plays at live + user can seek back freely

- Khôi phục liveSyncDurationCount=3 để stream start đúng ở live edge
- MANIFEST_PARSED: seek to duration (live edge) trước khi play
- Thêm seeking/seeked interceptor: nếu HLS.js snap về live nhưng user đang xem behind → restore position
- _dvrRestoreLock chặn loop khi restore
- Giữ _dvrUserSeeking pause/resume khi drag DVR handle

static/yt_live.js

@@ -1,6 +1,6 @@
-// === VNEWS — VTV LIVE + Inline Recorder v9 ===
+// === VNEWS — VTV LIVE + Inline Recorder v10 ===
 // Features: DVR 5-min rewind buffer (seek & stay), PiP, mini-player, INLINE RECORDER with ratio crop + AI title + Short AI upload
-// v9: Fix DVR seek snap-back — disable HLS auto-live-sync (liveSyncDurationCount=999999), pause during drag, resume on release
+// v10: Fix DVR — keep liveSync for stream start, but intercept HLS auto-snap via seeking/seeked events to preserve user position
 
 (function(){
   if(window._ytLiveLoaded) return;
@@ -721,19 +721,13 @@
     if (_dvrSeekBarTimer) clearInterval(_dvrSeekBarTimer);
     _dvrSeekBarTimer = setInterval(updateDVRUI, 1000);
 
-    // v9: Only auto-live if user is NOT seeking and playhead reached buffer edge
+    // v10: Track whether playhead is at live edge (for seeked event guard)
     video.addEventListener('timeupdate', function() {
-      if (_dvrUserSeeking) return; // don't interfere during seek
       if (!_hls) return;
       const dur = video.duration;
       if (!dur || !isFinite(dur)) return;
-      // If playhead is at the very end of buffer (live edge), keep it there
       const behind = dur - video.currentTime;
-      if (behind < 2) {
-        _dvrLastSeenEdge = true;
-      } else {
-        _dvrLastSeenEdge = false;
-      }
+      _dvrLastSeenEdge = (behind < 2);
     });
   }
 
@@ -850,20 +844,46 @@
     if(idx>=urls.length){loadEl.style.display='none';errEl.style.display='flex';errMsg.textContent=name+': Tất cả nguồn lỗi.';return;}
     const src=urls[idx]; loadEl.innerHTML='<div class="vtv-spinner"></div>Kết nối '+name+' ('+(idx+1)+'/'+urls.length+')...';
     if(typeof Hls!=='undefined'&&Hls.isSupported()){
-      // v9: DVR 5min — disable auto-live-sync so user can seek back freely
+      // v10: DVR 5min — keep liveSync for edge tracking, but override seek snap-back
       const hls=new Hls({
         enableWorker:true,lowLatencyMode:false,startLevel:0,capLevelToPlayerSize:true,
         maxBufferLength:120,maxMaxBufferLength:180,
         liveBackBufferLength:DVR_BUFFER_SECONDS,
-        liveSyncDurationCount:999999,liveMaxLatencyDurationCount:999999,
+        liveSyncDurationCount:3,liveMaxLatencyDurationCount:6,
         fragLoadingTimeOut:10000,manifestLoadingTimeOut:10000
       });
       _hls=hls; hls.loadSource(src); hls.attachMedia(video);
-      hls.on(Hls.Events.MANIFEST_PARSED,()=>{
+      // v10: After manifest loaded, seek to live edge first, then play
+      hls.on(Hls.Events.MANIFEST_PARSED,(ev,data)=>{
         loadEl.style.display='none';video.style.display='block';
-        // v9: Start playing but don't force live edge — let DVR seek bar handle it
+        // Start at live edge so stream plays immediately
+        const dur = video.duration;
+        if(dur && isFinite(dur)){ video.currentTime = dur; }
         video.play().catch(()=>{});
       });
+      // (live-snap interception handled via video seeking/seeked events below)
+      // v10: Block HLS auto-live-snap — restore user position when HLS fights back
+      let _preSeekTime = 0;
+      let _dvrRestoreLock = false; // prevent restore loop
+      video.addEventListener('seeking',function(){
+        if(_dvrRestoreLock) return;
+        _preSeekTime = video.currentTime;
+      });
+      video.addEventListener('seeked',function(){
+        if(_dvrUserSeeking || _dvrRestoreLock) return;
+        const dur = video.duration;
+        if(!dur || !isFinite(dur)) return;
+        const behind = dur - video.currentTime;
+        // If HLS.js snapped to live (behind < 0.5s) but user was >3s behind, restore
+        if(behind < 0.5 && _preSeekTime > 0){
+          const userBehind = dur - _preSeekTime;
+          if(userBehind > 3){
+            _dvrRestoreLock = true;
+            video.currentTime = _preSeekTime;
+            setTimeout(()=>{ _dvrRestoreLock = false; },500);
+          }
+        }
+      });
       let rec=0; hls.on(Hls.Events.ERROR,(ev,data)=>{if(data.fatal){if(data.type===Hls.ErrorTypes.NETWORK_ERROR){rec++;if(rec<=3)setTimeout(()=>hls.startLoad(),2000);else{hls.destroy();_hls=null;_tryPlay(video,urls,idx+1,name,loadEl,errEl,errMsg);}}else if(data.type===Hls.ErrorTypes.MEDIA_ERROR){try{hls.recoverMediaError();}catch(e){}}else{hls.destroy();_hls=null;_tryPlay(video,urls,idx+1,name,loadEl,errEl,errMsg);}}});
     }else if(video.canPlayType('application/vnd.apple.mpegurl')){
       video.src=src;