refactor: CompositeTrackPicker control and some playback settings

Screenbox.Core/Common/ServiceHelpers.cs

@@ -43,6 +43,7 @@ public static void PopulateCoreServices(ServiceCollection services)
         services.AddTransient<PlaylistsPageViewModel>();
         services.AddTransient<SelectionViewModel>();
         services.AddSingleton<CommonViewModel>();   // Shared between many pages
+        services.AddSingleton<PlaybackSessionViewModel>(); // Playback customization settings; Avoid thread lock
         services.AddSingleton<VolumeViewModel>();   // Avoid thread lock
 
         // Factories

Screenbox.Core/Enums/TrackPickerDisplayMode.cs

@@ -0,0 +1,8 @@
+namespace Screenbox.Core.Enums;
+
+public enum TrackPickerDisplayMode
+{
+    Composite,
+    Audio,
+    Subtitle,
+}

Screenbox.Core/Messages/ResetPlaybackSessionMessage.cs

@@ -0,0 +1,5 @@
+namespace Screenbox.Core.Messages;
+
+public sealed class ResetPlaybackSessionMessage
+{
+}

Screenbox.Core/ViewModels/CompositeTrackPickerViewModel.cs

@@ -58,6 +58,17 @@ public sealed partial class CompositeTrackPickerViewModel : ObservableRecipient,
     /// </summary>
     [ObservableProperty] public partial int VideoTrackIndex { get; set; }
 
+    /// <summary>
+    /// Gets or sets a value that indicates whether the flyout shows audio, subtitle,
+    /// or composite options in the picker.
+    /// </summary>
+    /// <returns>
+    /// A value of the enumeration that indicates whether the flyout shows audio, subtitle,
+    /// or composite options. The default is <b><see cref="TrackPickerDisplayMode.Composite"/></b>.
+    /// </returns>
+    [ObservableProperty]
+    public partial TrackPickerDisplayMode DisplayMode { get; set; } = TrackPickerDisplayMode.Composite;
+
     private readonly IFilesService _filesService;
     private readonly ISettingsService _settingsService;
     private readonly PlayerContext _playerContext;
@@ -76,6 +87,7 @@ public CompositeTrackPickerViewModel(PlayerContext playerContext, IFilesService
         SubtitleTracks = new ObservableCollection<string>();
         AudioTracks = new ObservableCollection<string>();
         VideoTracks = new ObservableCollection<string>();
+        DisplayMode = TrackPickerDisplayMode.Composite;
 
         Messenger.Register<QueueCurrentItemChangedMessage>(this);
     }
@@ -286,7 +298,6 @@ private async Task AddSubtitleAsync()
         }
     }
 
-
     public void OnFlyoutOpening()
     {
         UpdateSubtitleTrackList();
@@ -302,6 +313,13 @@ public void OnFlyoutOpening()
     public void OnFlyoutClosed()
     {
         _flyoutOpened = false;
+        DisplayMode = TrackPickerDisplayMode.Composite;
+    }
+
+    [RelayCommand]
+    private void SetDisplayMode(TrackPickerDisplayMode value)
+    {
+        DisplayMode = value;
     }
 
     private void UpdateAudioTrackList()

Screenbox.Core/ViewModels/PlaybackSessionViewModel.cs

@@ -0,0 +1,134 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using CommunityToolkit.Mvvm.Messaging;
+using CommunityToolkit.Mvvm.Messaging.Messages;
+using Screenbox.Core.Contexts;
+using Screenbox.Core.Events;
+using Screenbox.Core.Messages;
+using Screenbox.Core.Playback;
+using Windows.System;
+
+namespace Screenbox.Core.ViewModels;
+
+public sealed partial class PlaybackSessionViewModel : ObservableRecipient,
+    IRecipient<ChangePlaybackRateRequestMessage>,
+    IRecipient<PropertyChangedMessage<IMediaPlayer?>>,
+    IRecipient<ResetPlaybackSessionMessage>
+{
+    [ObservableProperty]
+    public partial double PlaybackRate { get; set; }
+
+    [ObservableProperty]
+    public partial double AudioTimingOffset { get; set; }
+
+    [ObservableProperty]
+    public partial double SubtitleTimingOffset { get; set; }
+
+    private IMediaPlayer? MediaPlayer => _playerContext.MediaPlayer;
+
+    private readonly PlayerContext _playerContext;
+    private readonly DispatcherQueue _dispatcherQueue;
+
+    public PlaybackSessionViewModel(PlayerContext playerContext)
+    {
+        _playerContext = playerContext;
+        _dispatcherQueue = DispatcherQueue.GetForCurrentThread();
+
+        PlaybackRate = 1.0;
+        AudioTimingOffset = 0.0;
+        SubtitleTimingOffset = 0.0;
+
+        Messenger.Register<ChangePlaybackRateRequestMessage>(this);
+        Messenger.Register<PropertyChangedMessage<IMediaPlayer?>>(this);
+        Messenger.Register<ResetPlaybackSessionMessage>(this);
+    }
+
+    public void Receive(PropertyChangedMessage<IMediaPlayer?> message)
+    {
+        if (message.Sender is not PlayerContext)
+            return;
+
+        if (message.OldValue is { } oldPlayer)
+        {
+            oldPlayer.PlaybackRateChanged -= OnPlaybackRateChanged;
+        }
+
+        if (MediaPlayer is not null)
+        {
+            MediaPlayer.PlaybackRateChanged += OnPlaybackRateChanged;
+        }
+    }
+
+    public void Receive(ChangePlaybackRateRequestMessage message)
+    {
+        SetPlaybackRate(message.Value);
+        message.Reply(PlaybackRate);
+    }
+
+    public void Receive(ResetPlaybackSessionMessage message)
+    {
+        ResetTimingOffsets();
+    }
+
+    partial void OnPlaybackRateChanged(double value)
+    {
+        if (MediaPlayer is null)
+            return;
+
+        MediaPlayer.PlaybackRate = value;
+    }
+
+    partial void OnAudioTimingOffsetChanged(double value)
+    {
+        if (MediaPlayer is null)
+            return;
+
+        if (MediaPlayer is VlcMediaPlayer vlcMediaPlayer)
+        {
+            vlcMediaPlayer.AudioDelay = value;
+        }
+    }
+
+    partial void OnSubtitleTimingOffsetChanged(double value)
+    {
+        if (MediaPlayer is null)
+            return;
+
+        if (MediaPlayer is VlcMediaPlayer vlcMediaPlayer)
+        {
+            vlcMediaPlayer.SubtitleDelay = value;
+        }
+    }
+
+    [RelayCommand]
+    private void SetPlaybackRate(double rate)
+    {
+        PlaybackRate = rate;
+    }
+
+    [RelayCommand]
+    private void AdjustAudioTimingOffset(double delta)
+    {
+        AudioTimingOffset += delta;
+    }
+
+    [RelayCommand]
+    private void AdjustSubtitleTimingOffset(double delta)
+    {
+        SubtitleTimingOffset += delta;
+    }
+
+    private void OnPlaybackRateChanged(IMediaPlayer sender, ValueChangedEventArgs<double> args)
+    {
+        _dispatcherQueue.TryEnqueue(() =>
+        {
+            sender.PlaybackRate = PlaybackRate;
+        });
+    }
+
+    private void ResetTimingOffsets()
+    {
+        AudioTimingOffset = 0.0;
+        SubtitleTimingOffset = 0.0;
+    }
+}

Screenbox.Core/ViewModels/PlayerControlsViewModel.cs

@@ -24,7 +24,6 @@ public sealed partial class PlayerControlsViewModel : ObservableRecipient,
     IRecipient<PropertyChangedMessage<IMediaPlayer?>>,
     IRecipient<SettingsChangedMessage>,
     IRecipient<TogglePlayPauseMessage>,
-    IRecipient<ChangePlaybackRateRequestMessage>,
     IRecipient<PropertyChangedMessage<PlayerVisibilityState>>,
     IRecipient<PropertyChangedMessage<WindowViewMode>>
 {
@@ -39,9 +38,6 @@ public sealed partial class PlayerControlsViewModel : ObservableRecipient,
     [ObservableProperty] public partial bool IsPlaying { get; set; }
     [ObservableProperty] public partial bool IsFullscreen { get; set; }
     [ObservableProperty] public partial string? TitleName { get; set; } // TODO: Handle VLC title name
-    [ObservableProperty] public partial double PlaybackRate { get; set; }
-    [ObservableProperty] public partial double AudioTimingOffset { get; set; }
-    [ObservableProperty] public partial double SubtitleTimingOffset { get; set; }
     [ObservableProperty] public partial bool IsAdvancedModeActive { get; set; }
     [ObservableProperty] public partial bool IsMinimal { get; set; }
     [ObservableProperty] public partial bool PlayerShowChapters { get; set; }
@@ -84,9 +80,6 @@ public PlayerControlsViewModel(
         _playerContext = playerContext;
         _filesService = filesService;
         _coordinator = coordinator;
-        PlaybackRate = 1.0;
-        AudioTimingOffset = 0.0;
-        SubtitleTimingOffset = 0.0;
         IsAdvancedModeActive = settingsService.AdvancedMode;
         IsMinimal = true;
         IsDisplayingRemainingTime = settingsService.PersistentShowRemainingTime;
@@ -104,7 +97,6 @@ public PlayerControlsViewModel(
         Messenger.Register<PropertyChangedMessage<IMediaPlayer?>>(this);
         Messenger.Register<SettingsChangedMessage>(this);
         Messenger.Register<TogglePlayPauseMessage>(this);
-        Messenger.Register<ChangePlaybackRateRequestMessage>(this);
         Messenger.Register<PropertyChangedMessage<PlayerVisibilityState>>(this);
         Messenger.Register<PropertyChangedMessage<WindowViewMode>>(this);
     }
@@ -151,12 +143,6 @@ public void Receive(TogglePlayPauseMessage message)
         }
     }
 
-    public void Receive(ChangePlaybackRateRequestMessage message)
-    {
-        SetPlaybackRate(message.Value);
-        message.Reply(PlaybackRate);
-    }
-
     public void Receive(PropertyChangedMessage<PlayerVisibilityState> message)
     {
         IsMinimal = message.NewValue != PlayerVisibilityState.Visible;
@@ -262,40 +248,13 @@ partial void OnIsDisplayingRemainingTimeChanged(bool value)
         _settingsService.PersistentShowRemainingTime = value;
     }
 
-    partial void OnPlaybackRateChanged(double value)
-    {
-        if (MediaPlayer == null) return;
-        MediaPlayer.PlaybackRate = value;
-    }
-
-    partial void OnAudioTimingOffsetChanged(double value)
-    {
-        if (MediaPlayer == null) return;
-
-        if (MediaPlayer is VlcMediaPlayer vlcMediaPlayer)
-        {
-            vlcMediaPlayer.AudioDelay = value;
-        }
-    }
-
-    partial void OnSubtitleTimingOffsetChanged(double value)
-    {
-        if (MediaPlayer == null) return;
-
-        if (MediaPlayer is VlcMediaPlayer vlcMediaPlayer)
-        {
-            vlcMediaPlayer.SubtitleDelay = value;
-        }
-    }
-
     private void PlayQueueOnPropertyChanged(object? sender, PropertyChangedEventArgs e)
     {
         switch (e.PropertyName)
         {
             case nameof(PlayQueueContext.CurrentItem):
                 HasActiveItem = PlayQueue.CurrentItem is not null;
-                SubtitleTimingOffset = 0;
-                AudioTimingOffset = 0;
+                Messenger.Send(new ResetPlaybackSessionMessage());
                 break;
         }
     }
@@ -364,12 +323,6 @@ private void ResetMediaPlayback()
         });
     }
 
-    [RelayCommand]
-    private void SetPlaybackRate(double rate)
-    {
-        PlaybackRate = rate;
-    }
-
     [RelayCommand]
     private void SetAspectRatio(string aspect)
     {