fix: eliminate video player blue screen on desktop with software rendering default and decoder toggle (v3.6.4)

lib/features/post/presentation/widgets/post_media_viewer.dart

@@ -78,6 +78,8 @@ class _PostMediaViewerState extends State<PostMediaViewer>
   String? _videoError;
   bool _retriedFormatError = false;
   bool _softwareDecodingFallback = false;
+  late bool _useSoftwareDecoding =
+      Platform.isLinux || Platform.isWindows || Platform.isMacOS;
   Timer? _hideTimer;
   StreamSubscription<String>? _errorSubscription;
   StreamSubscription<Duration>? _positionSubscription;
@@ -109,6 +111,8 @@ class _PostMediaViewerState extends State<PostMediaViewer>
       _videoError = null;
       _retriedFormatError = false;
       _softwareDecodingFallback = false;
+      _useSoftwareDecoding =
+          Platform.isLinux || Platform.isWindows || Platform.isMacOS;
       _imageUrls = _buildImageUrls(widget.post);
       _videoUrls = _buildVideoUrls(widget.post);
       if (_isPlayableMedia(widget.post) && _videoUrls.isNotEmpty) {
@@ -226,6 +230,11 @@ class _PostMediaViewerState extends State<PostMediaViewer>
               aspectRatio: widget.post.width > 0 && widget.post.height > 0
                   ? widget.post.width / widget.post.height
                   : 16 / 9,
+              previewUrl: widget.post.previewUrl.isNotEmpty
+                  ? widget.post.previewUrl
+                  : widget.post.sampleUrl,
+              isSoftwareDecoding: _useSoftwareDecoding,
+              onToggleDecoder: _toggleDecoderMode,
               controlsVisible: _controlsVisible,
               coverVideo: _coverVideo,
               muted: _muted,
@@ -444,13 +453,12 @@ class _PostMediaViewerState extends State<PostMediaViewer>
   void _initializeVideo() {
     MediaKit.ensureInitialized();
     _player = Player();
+    final bool enableHw = !_useSoftwareDecoding && !_softwareDecodingFallback;
     _controller = VideoController(
       _player!,
       configuration: VideoControllerConfiguration(
-        enableHardwareAcceleration: !_softwareDecodingFallback,
-        hwdec: _softwareDecodingFallback
-            ? 'no'
-            : (Platform.isAndroid ? 'auto-safe' : 'auto'),
+        enableHardwareAcceleration: enableHw,
+        hwdec: enableHw ? (Platform.isAndroid ? 'auto-safe' : 'auto') : 'no',
       ),
     );
     _applyVolume();
@@ -525,6 +533,7 @@ class _PostMediaViewerState extends State<PostMediaViewer>
             lower.contains('failed to recognize file format'))) {
       _retriedFormatError = true;
       _softwareDecodingFallback = true;
+      _useSoftwareDecoding = true;
       _disposeVideo();
       await Future<void>.delayed(const Duration(milliseconds: 250));
       if (mounted) {
@@ -542,6 +551,7 @@ class _PostMediaViewerState extends State<PostMediaViewer>
     _videoIndex = 0;
     _retriedFormatError = false;
     _softwareDecodingFallback = true;
+    _useSoftwareDecoding = true;
     _disposeVideo();
     await Future<void>.delayed(const Duration(milliseconds: 150));
     if (mounted) {
@@ -549,6 +559,26 @@ class _PostMediaViewerState extends State<PostMediaViewer>
     }
   }
 
+  void _toggleDecoderMode() {
+    setState(() {
+      _useSoftwareDecoding = !_useSoftwareDecoding;
+      _softwareDecodingFallback = false;
+      _retriedFormatError = false;
+    });
+    _disposeVideo();
+    _initializeVideo();
+    ScaffoldMessenger.maybeOf(context)?.showSnackBar(
+      SnackBar(
+        content: Text(
+          _useSoftwareDecoding
+              ? 'Включено программное декодирование (S/W)'
+              : 'Включено аппаратное декодирование (H/W)',
+        ),
+        duration: const Duration(seconds: 2),
+      ),
+    );
+  }
+
   void _disposeVideo() {
     _hideTimer?.cancel();
     _errorSubscription?.cancel();
@@ -690,6 +720,11 @@ class _PostMediaViewerState extends State<PostMediaViewer>
           halfVolume: _halfVolume,
           coverVideo: _coverVideo,
           initialVolume: _currentVolume,
+          previewUrl: widget.post.previewUrl.isNotEmpty
+              ? widget.post.previewUrl
+              : widget.post.sampleUrl,
+          isSoftwareDecoding: _useSoftwareDecoding,
+          onToggleDecoder: _toggleDecoderMode,
           errorMessage: _videoError,
           onRetry: _retryVideo,
           onChanged: (snapshot) {
@@ -886,6 +921,9 @@ class _FullscreenVideoPage extends StatefulWidget {
     required this.halfVolume,
     required this.coverVideo,
     this.initialVolume = 100.0,
+    this.previewUrl,
+    required this.isSoftwareDecoding,
+    required this.onToggleDecoder,
     required this.errorMessage,
     required this.onRetry,
     required this.onChanged,
@@ -900,6 +938,9 @@ class _FullscreenVideoPage extends StatefulWidget {
   final bool halfVolume;
   final bool coverVideo;
   final double initialVolume;
+  final String? previewUrl;
+  final bool isSoftwareDecoding;
+  final VoidCallback onToggleDecoder;
   final String? errorMessage;
   final VoidCallback onRetry;
   final ValueChanged<VideoPlaybackSnapshot> onChanged;
@@ -1024,6 +1065,9 @@ class _FullscreenVideoPageState extends State<_FullscreenVideoPage> {
                 player: widget.player,
                 controller: widget.controller,
                 aspectRatio: widget.aspectRatio,
+                previewUrl: widget.previewUrl,
+                isSoftwareDecoding: widget.isSoftwareDecoding,
+                onToggleDecoder: widget.onToggleDecoder,
                 controlsVisible: _controlsVisible,
                 coverVideo: _coverVideo,
                 muted: _muted,
@@ -1575,6 +1619,9 @@ class _VideoSurface extends StatefulWidget {
     required this.player,
     required this.controller,
     required this.aspectRatio,
+    this.previewUrl,
+    required this.isSoftwareDecoding,
+    required this.onToggleDecoder,
     required this.controlsVisible,
     required this.coverVideo,
     required this.muted,
@@ -1599,6 +1646,9 @@ class _VideoSurface extends StatefulWidget {
   final Player player;
   final VideoController controller;
   final double aspectRatio;
+  final String? previewUrl;
+  final bool isSoftwareDecoding;
+  final VoidCallback onToggleDecoder;
   final bool controlsVisible;
   final bool coverVideo;
   final bool muted;
@@ -1757,15 +1807,22 @@ class _VideoSurfaceState extends State<_VideoSurface> {
         return Stack(
           fit: StackFit.expand,
           children: [
-            ColoredBox(
-              color: Colors.black,
-              child: Video(
-                controller: widget.controller,
-                fit: widget.coverVideo ? BoxFit.cover : BoxFit.contain,
-                controls: null,
-                pauseUponEnteringBackgroundMode: false,
-                resumeUponEnteringForegroundMode: false,
+            if (widget.previewUrl != null && widget.previewUrl!.isNotEmpty)
+              Positioned.fill(
+                child: CachedNetworkImage(
+                  imageUrl: widget.previewUrl!,
+                  fit: widget.coverVideo ? BoxFit.cover : BoxFit.contain,
+                  memCacheWidth: 1920,
+                  memCacheHeight: 1080,
+                ),
               ),
+            Video(
+              controller: widget.controller,
+              fit: widget.coverVideo ? BoxFit.cover : BoxFit.contain,
+              fill: Colors.transparent,
+              controls: null,
+              pauseUponEnteringBackgroundMode: false,
+              resumeUponEnteringForegroundMode: false,
             ),
             if (_currentBrightness < 0.99)
               Positioned.fill(
@@ -1844,6 +1901,8 @@ class _VideoSurfaceState extends State<_VideoSurface> {
                   fullscreen: widget.fullscreen,
                   isLocked: _isLocked,
                   isLandscape: widget.isLandscape,
+                  isSoftwareDecoding: widget.isSoftwareDecoding,
+                  onToggleDecoder: widget.onToggleDecoder,
                   onToggleOrientation: widget.onToggleOrientation,
                   onToggleLock: () => setState(() => _isLocked = !_isLocked),
                   onToggleFit: widget.onToggleFit,
@@ -2655,6 +2714,8 @@ class _VideoControls extends StatefulWidget {
     required this.fullscreen,
     required this.isLocked,
     this.isLandscape,
+    required this.isSoftwareDecoding,
+    required this.onToggleDecoder,
     this.onToggleOrientation,
     required this.onToggleLock,
     required this.onToggleFit,
@@ -2674,6 +2735,8 @@ class _VideoControls extends StatefulWidget {
   final bool fullscreen;
   final bool isLocked;
   final bool? isLandscape;
+  final bool isSoftwareDecoding;
+  final VoidCallback onToggleDecoder;
   final VoidCallback? onToggleOrientation;
   final VoidCallback onToggleLock;
   final VoidCallback onToggleFit;
@@ -2773,6 +2836,17 @@ class _VideoControlsState extends State<_VideoControls> {
                         onPressed: widget.onToggleLock,
                       ),
                       const Spacer(),
+                      _RoundControlButton(
+                        tooltip: widget.isSoftwareDecoding
+                            ? 'Декодер: S/W (программный). Нажмите для переключения на H/W'
+                            : 'Декодер: H/W (аппаратный). Нажмите для переключения на S/W',
+                        selected: !widget.isSoftwareDecoding,
+                        icon: widget.isSoftwareDecoding
+                            ? Icons.memory_rounded
+                            : Icons.speed_rounded,
+                        onPressed: widget.onToggleDecoder,
+                      ),
+                      const SizedBox(width: 8),
                       _SpeedBadgeButton(
                         currentRate: currentRate,
                         onSelected: (newRate) => widget.player.setRate(newRate),