Updated certain events to have more concrete event arguments. Added try-catch block around playlist save logic. Added DispatchQueue where necessary.

Harmonia.Core/Playlists/IPlaylistManager.cs

@@ -13,4 +13,5 @@ public interface IPlaylistManager
     event EventHandler? CurrentPlaylistChanged;
     event EventHandler<PlaylistAddedEventArgs> PlaylistAdded;
     event EventHandler<PlaylistRemovedEventArgs> PlaylistRemoved;
+    event EventHandler<PlaylistSaveFailedEventArgs>? PlaylistSaveFailed;
 }

Harmonia.Core/Playlists/PlaylistManager.cs

@@ -25,6 +25,7 @@ public class PlaylistManager : IPlaylistManager
     public event EventHandler? CurrentPlaylistChanged;
     public event EventHandler<PlaylistAddedEventArgs>? PlaylistAdded;
     public event EventHandler<PlaylistRemovedEventArgs>? PlaylistRemoved;
+    public event EventHandler<PlaylistSaveFailedEventArgs>? PlaylistSaveFailed;
 
     public PlaylistManager(IPlaylistRepository playlistRepository)
     {
@@ -60,7 +61,7 @@ public class PlaylistManager : IPlaylistManager
             _playlistsBySongUid[song.UID] = playlist;
         }
 
-        await playlistRepository.SaveAsync(playlist);
+        await SavePlaylistAsync(playlist);
 
         PlaylistAdded?.Invoke(this, new(playlist));
 
@@ -108,6 +109,18 @@ public class PlaylistManager : IPlaylistManager
                 break;
         }
 
-        await playlistRepository.SaveAsync(playlist);
+        await SavePlaylistAsync(playlist);
+    }
+
+    private async Task SavePlaylistAsync(Playlist playlist)
+    {
+        try
+        {
+            await playlistRepository.SaveAsync(playlist);
+        }
+        catch (Exception ex) when (ex is IOException or UnauthorizedAccessException)
+        {
+            PlaylistSaveFailed?.Invoke(this, new(playlist, ex));
+        }
     }
 }

Harmonia.Core/Playlists/PlaylistSaveFailedEventArgs.cs

@@ -0,0 +1,7 @@
+namespace Harmonia.Core.Playlists;
+
+public class PlaylistSaveFailedEventArgs(Playlist playlist, Exception exception) : EventArgs
+{
+    public Playlist Playlist { get; } = playlist;
+    public Exception Exception { get; } = exception;
+}