From 4b88a53d0810c6dc34654b94b4d1b18f26fa66fc Mon Sep 17 00:00:00 2001
From: Yuto Terada <lugongdao07@gmail.com>
Date: Wed, 25 Dec 2024 17:23:57 +0900
Subject: [PATCH] Implement Equals method for IImageSource and IVideoSource
 Fixes #1210

---
 src/Beutl.Engine/Media/Source/BitmapSource.cs |  7 +++++++
 src/Beutl.Engine/Media/Source/SoundSource.cs  | 21 +++++++++++++------
 src/Beutl.Engine/Media/Source/VideoSource.cs  |  8 ++++++-
 3 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/src/Beutl.Engine/Media/Source/BitmapSource.cs b/src/Beutl.Engine/Media/Source/BitmapSource.cs
index 0354bc484..c5b456984 100644
--- a/src/Beutl.Engine/Media/Source/BitmapSource.cs
+++ b/src/Beutl.Engine/Media/Source/BitmapSource.cs
@@ -76,4 +76,11 @@ protected override void OnDispose(bool disposing)
     {
         _bitmap.Dispose();
     }
+
+    public override bool Equals(object? obj)
+    {
+        return obj is BitmapSource source
+               && !IsDisposed && !source.IsDisposed
+               && ReferenceEquals(_bitmap.Value, source._bitmap.Value);
+    }
 }
diff --git a/src/Beutl.Engine/Media/Source/SoundSource.cs b/src/Beutl.Engine/Media/Source/SoundSource.cs
index be3961179..234ef41aa 100644
--- a/src/Beutl.Engine/Media/Source/SoundSource.cs
+++ b/src/Beutl.Engine/Media/Source/SoundSource.cs
@@ -7,6 +7,8 @@ namespace Beutl.Media.Source;
 
 public class SoundSource(Ref<MediaReader> mediaReader, string fileName) : ISoundSource
 {
+    private readonly Ref<MediaReader> _mediaReader = mediaReader;
+
     ~SoundSource()
     {
         Dispose();
@@ -46,7 +48,7 @@ public void Dispose()
     {
         if (!IsDisposed)
         {
-            mediaReader.Dispose();
+            _mediaReader.Dispose();
             GC.SuppressFinalize(this);
             IsDisposed = true;
         }
@@ -56,7 +58,7 @@ public SoundSource Clone()
     {
         ObjectDisposedException.ThrowIf(IsDisposed, this);
 
-        return new SoundSource(mediaReader.Clone(), Name);
+        return new SoundSource(_mediaReader.Clone(), Name);
     }
 
     public bool Read(int start, int length, [NotNullWhen(true)] out IPcm? sound)
@@ -67,7 +69,7 @@ public bool Read(int start, int length, [NotNullWhen(true)] out IPcm? sound)
             return false;
         }
 
-        return mediaReader.Value.ReadAudio(start, length, out sound);
+        return _mediaReader.Value.ReadAudio(start, length, out sound);
     }
 
     public bool Read(TimeSpan start, TimeSpan length, [NotNullWhen(true)] out IPcm? sound)
@@ -78,7 +80,7 @@ public bool Read(TimeSpan start, TimeSpan length, [NotNullWhen(true)] out IPcm?
             return false;
         }
 
-        return mediaReader.Value.ReadAudio(ToSamples(start), ToSamples(length), out sound);
+        return _mediaReader.Value.ReadAudio(ToSamples(start), ToSamples(length), out sound);
     }
 
     public bool Read(TimeSpan start, int length, [NotNullWhen(true)] out IPcm? sound)
@@ -89,7 +91,7 @@ public bool Read(TimeSpan start, int length, [NotNullWhen(true)] out IPcm? sound
             return false;
         }
 
-        return mediaReader.Value.ReadAudio(ToSamples(start), length, out sound);
+        return _mediaReader.Value.ReadAudio(ToSamples(start), length, out sound);
     }
 
     public bool Read(int start, TimeSpan length, [NotNullWhen(true)] out IPcm? sound)
@@ -100,11 +102,18 @@ public bool Read(int start, TimeSpan length, [NotNullWhen(true)] out IPcm? sound
             return false;
         }
 
-        return mediaReader.Value.ReadAudio(start, ToSamples(length), out sound);
+        return _mediaReader.Value.ReadAudio(start, ToSamples(length), out sound);
     }
 
     ISoundSource ISoundSource.Clone() => Clone();
 
+    public override bool Equals(object? obj)
+    {
+        return obj is SoundSource source
+               && !IsDisposed && !source.IsDisposed
+               && ReferenceEquals(_mediaReader.Value, source._mediaReader.Value);
+    }
+
     private int ToSamples(TimeSpan timeSpan)
     {
         return (int)(timeSpan.TotalSeconds * SampleRate);
diff --git a/src/Beutl.Engine/Media/Source/VideoSource.cs b/src/Beutl.Engine/Media/Source/VideoSource.cs
index 135dd3246..ac43f7b4e 100644
--- a/src/Beutl.Engine/Media/Source/VideoSource.cs
+++ b/src/Beutl.Engine/Media/Source/VideoSource.cs
@@ -1,5 +1,4 @@
 using System.Diagnostics.CodeAnalysis;
-
 using Beutl.Media.Decoding;
 
 namespace Beutl.Media.Source;
@@ -94,6 +93,13 @@ public bool Read(int frame, [NotNullWhen(true)] out IBitmap? bitmap)
         return _mediaReader.Value.ReadVideo(frame, out bitmap);
     }
 
+    public override bool Equals(object? obj)
+    {
+        return obj is VideoSource source
+               && !IsDisposed && !source.IsDisposed
+               && ReferenceEquals(_mediaReader.Value, source._mediaReader.Value);
+    }
+
     IVideoSource IVideoSource.Clone() => Clone();
 
     IMediaSource IMediaSource.Clone() => Clone();