Backport pull request #18037 from jellyfin/release-12.z

Enforce channel mediasource id

Original-merge: 941e419a2c

Merged-by: crobibero <cody@robibe.ro>

Backported-by: Cody Robibero <cody@robibe.ro>

src/Jellyfin.LiveTv/Channels/ChannelManager.cs

@@ -372,9 +372,7 @@ namespace Jellyfin.LiveTv.Channels
         {
             IEnumerable<MediaSourceInfo> results = GetSavedMediaSources(item);
 
-            return results
-                .Select(i => NormalizeMediaSource(item, i))
-                .ToList();
+            return NormalizeMediaSources(item, results);
         }
 
         /// <summary>
@@ -400,9 +398,7 @@ namespace Jellyfin.LiveTv.Channels
                 results = Enumerable.Empty<MediaSourceInfo>();
             }
 
-            return results
-                .Select(i => NormalizeMediaSource(item, i))
-                .ToList();
+            return NormalizeMediaSources(item, results);
         }
 
         private async Task<IEnumerable<MediaSourceInfo>> GetChannelItemMediaSourcesInternal(IRequiresMediaInfoCallback channel, string id, CancellationToken cancellationToken)
@@ -420,11 +416,36 @@ namespace Jellyfin.LiveTv.Channels
             return list;
         }
 
-        private static MediaSourceInfo NormalizeMediaSource(BaseItem item, MediaSourceInfo info)
+        private static IReadOnlyList<MediaSourceInfo> NormalizeMediaSources(BaseItem item, IEnumerable<MediaSourceInfo> infos)
         {
-            info.RunTimeTicks ??= item.RunTimeTicks;
+            var list = infos.ToList();
+            var itemId = item.Id.ToString("N", CultureInfo.InvariantCulture);
+            var hasDefaultSource = list.Any(i => string.Equals(i.Id, itemId, StringComparison.OrdinalIgnoreCase));
 
-            return info;
+            for (var index = 0; index < list.Count; index++)
+            {
+                var info = list[index];
+                info.RunTimeTicks ??= item.RunTimeTicks;
+
+                if (!string.IsNullOrEmpty(info.Id))
+                {
+                    continue;
+                }
+
+                if (!hasDefaultSource)
+                {
+                    // The source carrying the item id sorts first and becomes the client's default.
+                    info.Id = itemId;
+                    hasDefaultSource = true;
+                    continue;
+                }
+
+                // Remaining sources need ids that are distinct but stable, as clients send them back to request playback.
+                var key = string.IsNullOrEmpty(info.Path) ? index.ToString(CultureInfo.InvariantCulture) : info.Path;
+                info.Id = (itemId + key).GetMD5().ToString("N", CultureInfo.InvariantCulture);
+            }
+
+            return list;
         }
 
         private async Task<Channel> GetChannel(IChannel channelInfo, CancellationToken cancellationToken)