From 73157cf759b0c8043255bd56228610259dd495a0 Mon Sep 17 00:00:00 2001
From: ScrubN <72096833+ScrubN@users.noreply.github.com>
Date: Sun, 10 Nov 2024 21:02:33 -0500
Subject: [PATCH] Support changing stream IDs depending on container type

---
 .../Tools/FfmpegConcatList.cs                 | 28 ++++++++++++++-----
 TwitchDownloaderCore/VideoDownloader.cs       | 17 ++++++++++-
 2 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/TwitchDownloaderCore/Tools/FfmpegConcatList.cs b/TwitchDownloaderCore/Tools/FfmpegConcatList.cs
index e8c3b37d..f9e4785b 100644
--- a/TwitchDownloaderCore/Tools/FfmpegConcatList.cs
+++ b/TwitchDownloaderCore/Tools/FfmpegConcatList.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Globalization;
 using System.IO;
 using System.Linq;
@@ -12,7 +13,7 @@ public static class FfmpegConcatList
     {
         private const string LINE_FEED = "\u000A";
 
-        public static async Task SerializeAsync(string filePath, M3U8 playlist, Range videoListCrop, CancellationToken cancellationToken = default)
+        public static async Task SerializeAsync(string filePath, M3U8 playlist, Range videoListCrop, StreamIds streamIds, CancellationToken cancellationToken = default)
         {
             await using var fs = new FileStream(filePath, FileMode.Create, FileAccess.Write, FileShare.Read);
             await using var sw = new StreamWriter(fs) { NewLine = LINE_FEED };
@@ -27,16 +28,29 @@ public static async Task SerializeAsync(string filePath, M3U8 playlist, Range vi
                 await sw.WriteAsync(DownloadTools.RemoveQueryString(stream.Path));
                 await sw.WriteLineAsync('\'');
 
-                await sw.WriteLineAsync("stream");
-                await sw.WriteLineAsync("exact_stream_id 0x100"); // Audio
-                await sw.WriteLineAsync("stream");
-                await sw.WriteLineAsync("exact_stream_id 0x101"); // Video
-                await sw.WriteLineAsync("stream");
-                await sw.WriteLineAsync("exact_stream_id 0x102"); // Subtitle
+                foreach (var id in streamIds.Ids)
+                {
+                    await sw.WriteLineAsync("stream");
+                    await sw.WriteLineAsync($"exact_stream_id {id}");
+                }
 
                 await sw.WriteAsync("duration ");
                 await sw.WriteLineAsync(stream.PartInfo.Duration.ToString(CultureInfo.InvariantCulture));
             }
         }
+
+        public record StreamIds
+        {
+            public static readonly StreamIds TransportStream = new("0x100", "0x101", "0x102");
+            public static readonly StreamIds Mp4 = new("0x1", "0x2");
+            public static readonly StreamIds None = new();
+
+            private StreamIds(params string[] ids)
+            {
+                Ids = ids;
+            }
+
+            public IEnumerable<string> Ids { get; }
+        }
     }
 }
\ No newline at end of file
diff --git a/TwitchDownloaderCore/VideoDownloader.cs b/TwitchDownloaderCore/VideoDownloader.cs
index b2f74b92..74c264bd 100644
--- a/TwitchDownloaderCore/VideoDownloader.cs
+++ b/TwitchDownloaderCore/VideoDownloader.cs
@@ -109,7 +109,8 @@ await FfmpegMetadata.SerializeAsync(metadataPath, downloadOptions.Id.ToString(),
                     videoChapterResponse.data.video.moments.edges);
 
                 var concatListPath = Path.Combine(downloadFolder, "concat.txt");
-                await FfmpegConcatList.SerializeAsync(concatListPath, playlist, videoListCrop, cancellationToken);
+                var streamIds = GetStreamIds(playlist);
+                await FfmpegConcatList.SerializeAsync(concatListPath, playlist, videoListCrop, streamIds, cancellationToken);
 
                 outputFs.Close();
 
@@ -318,6 +319,20 @@ private async Task VerifyDownloadedParts(ICollection<M3U8.Stream> playlist, Rang
             }
         }
 
+        private FfmpegConcatList.StreamIds GetStreamIds(M3U8 playlist)
+        {
+            var path = DownloadTools.RemoveQueryString(playlist.Streams.FirstOrDefault()?.Path ?? "");
+            var extension = Path.GetExtension(path);
+            if (extension is ".mp4")
+                return FfmpegConcatList.StreamIds.Mp4;
+
+            if (extension is ".ts")
+                return FfmpegConcatList.StreamIds.TransportStream;
+
+            _progress.LogWarning("No file extension was found! Assuming TS.");
+            return FfmpegConcatList.StreamIds.TransportStream;
+        }
+
         private async Task<int> RunFfmpegVideoCopy(string tempFolder, FileInfo outputFile, string concatListPath, string metadataPath, decimal startOffset, decimal endDuration, TimeSpan videoLength, bool disableAudioCopy, CancellationToken cancellationToken)
         {
             using var process = new Process