fix: avoid duplicate timeline seek

close #1421

lib/widgets/video_controls/parts/playback_input.dart

@@ -78,6 +78,14 @@ extension _PlexVideoControlsPlaybackInputMethods on _PlexVideoControlsState {
     }
   }
 
+  Future<void> _seekToTimelinePosition(Duration position) {
+    final clamped = clampSeekPosition(widget.player, position);
+    final seekFuture = _seekToPosition(clamped, notifyCompletion: false);
+    _lastDispatchedTimelineSeek = clamped;
+    _lastDispatchedTimelineSeekFuture = seekFuture;
+    return seekFuture;
+  }
+
   Future<void> _playOrPause() async {
     if (!widget.player.state.playing && _rewindOnResume > 0) {
       final target = widget.player.state.position - Duration(seconds: _rewindOnResume);
@@ -89,14 +97,39 @@ extension _PlexVideoControlsPlaybackInputMethods on _PlexVideoControlsState {
 
   /// Throttled seek for timeline slider - executes immediately then throttles to 200ms
   void _throttledSeek(Duration position) {
-    if (widget.isTranscoding) return;
+    if (widget.isTranscoding) {
+      _lastDispatchedTimelineSeek = null;
+      _lastDispatchedTimelineSeekFuture = null;
+      return;
+    }
     _seekThrottle([position]);
   }
 
   /// Finalizes the seek when user stops scrubbing the timeline
   void _finalizeSeek(Duration position) {
     _seekThrottle.cancel();
-    unawaited(_seekToPosition(position));
+    final clamped = clampSeekPosition(widget.player, position);
+
+    if (shouldSkipDuplicateTimelineSeek(
+      isTranscoding: widget.isTranscoding,
+      lastDispatchedSeek: _lastDispatchedTimelineSeek,
+      finalSeek: clamped,
+    )) {
+      final seekFuture = _lastDispatchedTimelineSeekFuture;
+      if (seekFuture == null) {
+        widget.onSeekCompleted?.call(clamped);
+        return;
+      }
+      unawaited(
+        seekFuture.then<void>((_) {
+          if (!mounted) return;
+          widget.onSeekCompleted?.call(clamped);
+        }),
+      );
+      return;
+    }
+
+    unawaited(_seekToPosition(clamped));
   }
 
   void _holdTimelineScrub() {

lib/widgets/video_controls/video_controls.dart

@@ -186,6 +186,15 @@ KeyEventResult handlePromptDismissBackKey(KeyEvent event, VoidCallback? onDismis
   return handleBackKeyAction(event, onDismissPrompt);
 }
 
+@visibleForTesting
+bool shouldSkipDuplicateTimelineSeek({
+  required bool isTranscoding,
+  required Duration? lastDispatchedSeek,
+  required Duration finalSeek,
+}) {
+  return !isTranscoding && lastDispatchedSeek == finalSeek;
+}
+
 typedef PlaybackSourceChangeCallback =
     Future<void> Function({
       int? newMediaIndex,
@@ -443,6 +452,8 @@ class _PlexVideoControlsState extends State<PlexVideoControls>
   Timer? _edgeAdjustmentIndicatorClearTimer;
   // Seek throttle
   late final Throttle _seekThrottle;
+  Duration? _lastDispatchedTimelineSeek;
+  Future<void>? _lastDispatchedTimelineSeekFuture;
   // Current marker state
   MediaMarker? _currentMarker;
   List<MediaMarker> _markers = [];
@@ -495,7 +506,7 @@ class _PlexVideoControlsState extends State<PlexVideoControls>
     _skipMarkerFocusNode = FocusNode(debugLabel: 'SkipMarkerButton');
     _seekThrottle = throttle(
       (Duration pos) {
-        unawaited(_seekToPosition(pos, notifyCompletion: false));
+        unawaited(_seekToTimelinePosition(pos));
       },
       const Duration(milliseconds: 200),
       leading: true,

test/widgets/video_controls_test.dart

@@ -729,6 +729,49 @@ void main() {
     });
   });
 
+  group('shouldSkipDuplicateTimelineSeek', () {
+    test('skips a matching non-transcode final seek', () {
+      expect(
+        shouldSkipDuplicateTimelineSeek(
+          isTranscoding: false,
+          lastDispatchedSeek: const Duration(minutes: 7, seconds: 30),
+          finalSeek: const Duration(minutes: 7, seconds: 30),
+        ),
+        isTrue,
+      );
+    });
+
+    test('does not skip matching transcode seek', () {
+      expect(
+        shouldSkipDuplicateTimelineSeek(
+          isTranscoding: true,
+          lastDispatchedSeek: const Duration(minutes: 7, seconds: 30),
+          finalSeek: const Duration(minutes: 7, seconds: 30),
+        ),
+        isFalse,
+      );
+    });
+
+    test('does not skip when no matching seek was already dispatched', () {
+      expect(
+        shouldSkipDuplicateTimelineSeek(
+          isTranscoding: false,
+          lastDispatchedSeek: const Duration(minutes: 7),
+          finalSeek: const Duration(minutes: 7, seconds: 30),
+        ),
+        isFalse,
+      );
+      expect(
+        shouldSkipDuplicateTimelineSeek(
+          isTranscoding: false,
+          lastDispatchedSeek: null,
+          finalSeek: const Duration(minutes: 7, seconds: 30),
+        ),
+        isFalse,
+      );
+    });
+  });
+
   group('SyncOffsetControl', () {
     testWidgets('uses 100ms slider steps without rendering tick marks', (tester) async {
       LocaleSettings.setLocaleSync(AppLocale.en);