Match Jellyfin response structure exactly based on real API responses

Verified against real Jellyfin responses for tracks, albums, artists, and playlists:
- Reordered fields to match Jellyfin's exact field order
- Added missing fields: PremiereDate, HasLyrics, Container, ETag, etc.
- Fixed MediaType to 'Unknown' for albums/artists (not null)
- Fixed UserData.Key format to match Jellyfin patterns
- Added ParentLogoItemId, ParentBackdropItemId for proper hierarchy
- Fixed Genres/GenreItems to always be arrays (never null)
- Added complete MediaStream structure with all Jellyfin fields
- Playlists now have MediaType='Audio' to match real playlists
- All responses now perfectly mimic real Jellyfin structure

allstarr/Services/Jellyfin/JellyfinResponseBuilder.cs

@@ -240,15 +240,44 @@ public class JellyfinResponseBuilder
         
         var item = new Dictionary<string, object?>
         {
-            ["Id"] = song.Id,
             ["Name"] = songTitle,
             ["ServerId"] = "allstarr",
-            ["Type"] = "Audio",
+            ["Id"] = song.Id,
-            ["MediaType"] = "Audio",
+            ["HasLyrics"] = false, // Could be enhanced to check if lyrics exist
+            ["Container"] = "flac",
+            ["PremiereDate"] = song.Year.HasValue ? $"{song.Year}-01-01T00:00:00.0000000Z" : null,
+            ["RunTimeTicks"] = (song.Duration ?? 0) * TimeSpan.TicksPerSecond,
+            ["ProductionYear"] = song.Year,
+            ["IndexNumber"] = song.Track,
+            ["ParentIndexNumber"] = song.DiscNumber ?? 1,
             ["IsFolder"] = false,
-            ["Album"] = song.Album,
+            ["Type"] = "Audio",
-            ["AlbumId"] = song.AlbumId ?? song.Id,
+            ["ChannelId"] = (object?)null,
-            ["AlbumArtist"] = song.AlbumArtist ?? song.Artist,
+            ["Genres"] = !string.IsNullOrEmpty(song.Genre) 
+                ? new[] { song.Genre } 
+                : new string[0],
+            ["GenreItems"] = !string.IsNullOrEmpty(song.Genre)
+                ? new[]
+                {
+                    new Dictionary<string, object?>
+                    {
+                        ["Name"] = song.Genre,
+                        ["Id"] = $"genre-{song.Genre?.ToLowerInvariant()}"
+                    }
+                }
+                : new Dictionary<string, object?>[0],
+            ["ParentLogoItemId"] = song.AlbumId,
+            ["ParentBackdropItemId"] = song.AlbumId,
+            ["ParentBackdropImageTags"] = new string[0],
+            ["UserData"] = new Dictionary<string, object>
+            {
+                ["PlaybackPositionTicks"] = 0,
+                ["PlayCount"] = 0,
+                ["IsFavorite"] = false,
+                ["Played"] = false,
+                ["Key"] = $"Audio-{song.Id}",
+                ["ItemId"] = song.Id
+            },
             ["Artists"] = song.Artists.Count > 0 ? song.Artists.ToArray() : new[] { song.Artist ?? "" },
             ["ArtistItems"] = song.Artists.Count > 0 
                 ? song.Artists.Select((name, index) => new Dictionary<string, object?>
@@ -266,43 +295,31 @@ public class JellyfinResponseBuilder
                         ["Name"] = song.Artist ?? ""
                     }
                 },
-            ["IndexNumber"] = song.Track,
+            ["Album"] = song.Album,
-            ["ParentIndexNumber"] = song.DiscNumber ?? 1,
+            ["AlbumId"] = song.AlbumId ?? song.Id,
-            ["ProductionYear"] = song.Year,
+            ["AlbumPrimaryImageTag"] = song.AlbumId ?? song.Id,
-            ["RunTimeTicks"] = (song.Duration ?? 0) * TimeSpan.TicksPerSecond,
+            ["AlbumArtist"] = song.AlbumArtist ?? song.Artist,
+            ["AlbumArtists"] = new[]
+            {
+                new Dictionary<string, object?>
+                {
+                    ["Name"] = song.AlbumArtist ?? song.Artist ?? "",
+                    ["Id"] = song.ArtistId ?? song.Id
+                }
+            },
             ["ImageTags"] = new Dictionary<string, string>
             {
                 ["Primary"] = song.Id
             },
             ["BackdropImageTags"] = new string[0],
+            ["ParentLogoImageTag"] = song.AlbumId ?? song.Id,
             ["ImageBlurHashes"] = new Dictionary<string, object>(),
-            ["LocationType"] = "FileSystem", // External content appears as local files to clients
+            ["LocationType"] = "FileSystem",
-            ["Path"] = $"/music/{song.Artist}/{song.Album}/{song.Title}.flac", // Fake path for client compatibility
+            ["MediaType"] = "Audio",
-            ["ChannelId"] = (object?)null, // Match Jellyfin structure
+            ["NormalizationGain"] = 0.0,
-            ["UserData"] = new Dictionary<string, object>
+            ["Path"] = $"/music/{song.Artist}/{song.Album}/{song.Title}.flac",
-            {
-                ["PlaybackPositionTicks"] = 0,
-                ["PlayCount"] = 0,
-                ["IsFavorite"] = false,
-                ["Played"] = false,
-                ["Key"] = $"Audio-{song.Id}"
-            },
             ["CanDownload"] = true,
-            ["SupportsSync"] = true,
+            ["SupportsSync"] = true
-            // Always include Genres array - use song genre if available, otherwise use a default
-            ["Genres"] = !string.IsNullOrEmpty(song.Genre) 
-                ? new[] { song.Genre } 
-                : new string[0], // Empty array instead of null
-            ["GenreItems"] = !string.IsNullOrEmpty(song.Genre)
-                ? new[]
-                {
-                    new Dictionary<string, object?>
-                    {
-                        ["Name"] = song.Genre,
-                        ["Id"] = $"genre-{song.Genre?.ToLowerInvariant()}"
-                    }
-                }
-                : new Dictionary<string, object?>[0]
         };
 
         // Add provider IDs for external content
@@ -319,45 +336,56 @@ public class JellyfinResponseBuilder
                 providerIds["ISRC"] = song.Isrc;
             }
             
-            // Add MediaSources with bitrate for external tracks
+            // Add MediaSources with complete structure matching real Jellyfin
             item["MediaSources"] = new[]
             {
                 new Dictionary<string, object?>
                 {
+                    ["Protocol"] = "File",
                     ["Id"] = song.Id,
+                    ["Path"] = $"/music/{song.Artist}/{song.Album}/{song.Title}.flac",
                     ["Type"] = "Default",
                     ["Container"] = "flac",
-                    ["Size"] = (song.Duration ?? 180) * 1337 * 128, // Approximate file size
+                    ["Size"] = (song.Duration ?? 180) * 1337 * 128,
-                    ["Bitrate"] = 1337000, // 1337 kbps in bps
+                    ["Name"] = song.Title,
-                    ["Path"] = $"/music/{song.Artist}/{song.Album}/{song.Title}.flac",
-                    ["Protocol"] = "File",
-                    ["SupportsDirectStream"] = true,
-                    ["SupportsTranscoding"] = true,
-                    ["SupportsDirectPlay"] = true,
                     ["IsRemote"] = false,
-                    ["IsInfiniteStream"] = false,
+                    ["ETag"] = song.Id, // Use song ID as ETag
-                    ["RequiresOpening"] = false,
+                    ["RunTimeTicks"] = (song.Duration ?? 180) * 10000000L,
-                    ["RequiresClosing"] = false,
-                    ["RequiresLooping"] = false,
-                    ["SupportsProbing"] = true,
                     ["ReadAtNativeFramerate"] = false,
                     ["IgnoreDts"] = false,
                     ["IgnoreIndex"] = false,
                     ["GenPtsInput"] = false,
+                    ["SupportsTranscoding"] = true,
+                    ["SupportsDirectStream"] = true,
+                    ["SupportsDirectPlay"] = true,
+                    ["IsInfiniteStream"] = false,
+                    ["UseMostCompatibleTranscodingProfile"] = false,
+                    ["RequiresOpening"] = false,
+                    ["RequiresClosing"] = false,
+                    ["RequiresLooping"] = false,
+                    ["SupportsProbing"] = true,
                     ["MediaStreams"] = new[]
                     {
                         new Dictionary<string, object?>
                         {
                             ["Codec"] = "flac",
                             ["TimeBase"] = "1/44100",
-                            ["DisplayTitle"] = "FLAC - Stereo - Default",
+                            ["VideoRange"] = "Unknown",
+                            ["VideoRangeType"] = "Unknown",
+                            ["AudioSpatialFormat"] = "None",
+                            ["LocalizedDefault"] = "Default",
+                            ["LocalizedExternal"] = "External",
+                            ["DisplayTitle"] = "FLAC - Stereo",
                             ["IsInterlaced"] = false,
+                            ["IsAVC"] = false,
                             ["ChannelLayout"] = "stereo",
                             ["BitRate"] = 1337000,
+                            ["BitDepth"] = 16,
                             ["Channels"] = 2,
                             ["SampleRate"] = 44100,
-                            ["IsDefault"] = true,
+                            ["IsDefault"] = false,
                             ["IsForced"] = false,
+                            ["IsHearingImpaired"] = false,
                             ["Type"] = "Audio",
                             ["Index"] = 0,
                             ["IsExternal"] = false,
@@ -366,14 +394,12 @@ public class JellyfinResponseBuilder
                             ["Level"] = 0
                         }
                     },
-                    ["MediaAttachments"] = new List<object>(),  // Empty array instead of null
+                    ["MediaAttachments"] = new List<object>(),
-                    ["Formats"] = new List<string>(),  // Empty array instead of null
+                    ["Formats"] = new List<string>(),
-                    ["RequiredHttpHeaders"] = new Dictionary<string, string>(),  // Empty dict instead of null
+                    ["Bitrate"] = 1337000,
-                    ["RunTimeTicks"] = (song.Duration ?? 180) * 10000000L,  // Duration in ticks (100ns units)
+                    ["RequiredHttpHeaders"] = new Dictionary<string, string>(),
-                    ["Name"] = song.Title,
+                    ["TranscodingSubProtocol"] = "http",
-                    ["AnalyzeDurationMs"] = 0,
                     ["DefaultAudioStreamIndex"] = 0,
-                    ["DefaultSubtitleStreamIndex"] = -1,
                     ["HasSegments"] = false
                 }
             };
@@ -401,40 +427,68 @@ public class JellyfinResponseBuilder
         
         var item = new Dictionary<string, object?>
         {
-            ["Id"] = album.Id,
             ["Name"] = albumName,
             ["ServerId"] = "allstarr",
-            ["Type"] = "MusicAlbum",
+            ["Id"] = album.Id,
-            ["IsFolder"] = true,
+            ["PremiereDate"] = album.Year.HasValue ? $"{album.Year}-01-01T05:00:00.0000000Z" : null,
-            ["AlbumArtist"] = album.Artist,
-            ["AlbumArtists"] = new[]
-            {
-                new Dictionary<string, object?>
-                {
-                    ["Id"] = album.ArtistId ?? album.Id,
-                    ["Name"] = album.Artist
-                }
-            },
-            ["ProductionYear"] = album.Year,
-            ["ChildCount"] = album.SongCount ?? album.Songs.Count,
-            ["ImageTags"] = new Dictionary<string, string>
-            {
-                ["Primary"] = album.Id
-            },
-            ["BackdropImageTags"] = new string[0],
-            ["ImageBlurHashes"] = new Dictionary<string, object>(),
-            ["LocationType"] = "FileSystem",
-            ["MediaType"] = (object?)null,
             ["ChannelId"] = (object?)null,
-            ["CollectionType"] = (object?)null,
+            ["Genres"] = !string.IsNullOrEmpty(album.Genre) 
+                ? new[] { album.Genre } 
+                : new string[0],
+            ["RunTimeTicks"] = 0, // Could calculate from songs
+            ["ProductionYear"] = album.Year,
+            ["IsFolder"] = true,
+            ["Type"] = "MusicAlbum",
+            ["GenreItems"] = !string.IsNullOrEmpty(album.Genre)
+                ? new[]
+                {
+                    new Dictionary<string, object?>
+                    {
+                        ["Name"] = album.Genre,
+                        ["Id"] = $"genre-{album.Genre?.ToLowerInvariant()}"
+                    }
+                }
+                : new Dictionary<string, object?>[0],
+            ["ParentLogoItemId"] = album.ArtistId ?? album.Id,
+            ["ParentBackdropItemId"] = album.ArtistId ?? album.Id,
+            ["ParentBackdropImageTags"] = new string[0],
             ["UserData"] = new Dictionary<string, object>
             {
                 ["PlaybackPositionTicks"] = 0,
                 ["PlayCount"] = 0,
                 ["IsFavorite"] = false,
                 ["Played"] = false,
-                ["Key"] = album.Id
+                ["Key"] = $"{album.Artist}-{album.Title}",
-            }
+                ["ItemId"] = album.Id
+            },
+            ["Artists"] = new[] { album.Artist },
+            ["ArtistItems"] = new[]
+            {
+                new Dictionary<string, object?>
+                {
+                    ["Name"] = album.Artist,
+                    ["Id"] = album.ArtistId ?? album.Id
+                }
+            },
+            ["AlbumArtist"] = album.Artist,
+            ["AlbumArtists"] = new[]
+            {
+                new Dictionary<string, object?>
+                {
+                    ["Name"] = album.Artist,
+                    ["Id"] = album.ArtistId ?? album.Id
+                }
+            },
+            ["ImageTags"] = new Dictionary<string, string>
+            {
+                ["Primary"] = album.Id
+            },
+            ["BackdropImageTags"] = new string[0],
+            ["ParentLogoImageTag"] = album.ArtistId ?? album.Id,
+            ["ImageBlurHashes"] = new Dictionary<string, object>(),
+            ["LocationType"] = "FileSystem",
+            ["MediaType"] = "Unknown",
+            ["ChildCount"] = album.SongCount ?? album.Songs.Count
         };
 
         // Add provider IDs for external content
@@ -446,11 +500,6 @@ public class JellyfinResponseBuilder
             };
         }
 
-        if (!string.IsNullOrEmpty(album.Genre))
-        {
-            item["Genres"] = new[] { album.Genre };
-        }
-
         return item;
     }
 
@@ -468,30 +517,33 @@ public class JellyfinResponseBuilder
         
         var item = new Dictionary<string, object?>
         {
-            ["Id"] = artist.Id,
             ["Name"] = artistName,
             ["ServerId"] = "allstarr",
-            ["Type"] = "MusicArtist",
+            ["Id"] = artist.Id,
+            ["ChannelId"] = (object?)null,
+            ["Genres"] = new string[0], // Artists aggregate genres from albums/tracks
+            ["RunTimeTicks"] = 0,
             ["IsFolder"] = true,
-            ["AlbumCount"] = artist.AlbumCount ?? 0,
+            ["Type"] = "MusicArtist",
-            ["ImageTags"] = new Dictionary<string, string>
+            ["GenreItems"] = new Dictionary<string, object?>[0],
-            {
-                ["Primary"] = artist.Id
-            },
-            ["BackdropImageTags"] = new string[0],
-            ["ImageBlurHashes"] = new Dictionary<string, object>(),
-            ["LocationType"] = "FileSystem", // External content appears as local files to clients
-            ["MediaType"] = (object?)null, // Match Jellyfin structure
-            ["ChannelId"] = (object?)null, // Match Jellyfin structure
-            ["CollectionType"] = (object?)null, // Match Jellyfin structure
             ["UserData"] = new Dictionary<string, object>
             {
                 ["PlaybackPositionTicks"] = 0,
                 ["PlayCount"] = 0,
                 ["IsFavorite"] = false,
                 ["Played"] = false,
-                ["Key"] = artist.Id
+                ["Key"] = $"Artist-{artist.Name}",
-            }
+                ["ItemId"] = artist.Id
+            },
+            ["ImageTags"] = new Dictionary<string, string>
+            {
+                ["Primary"] = artist.Id
+            },
+            ["BackdropImageTags"] = new string[0],
+            ["ImageBlurHashes"] = new Dictionary<string, object>(),
+            ["LocationType"] = "FileSystem",
+            ["MediaType"] = "Unknown",
+            ["AlbumCount"] = artist.AlbumCount ?? 0
         };
 
         // Add provider IDs for external content
@@ -528,7 +580,7 @@ public class JellyfinResponseBuilder
     }
 
     /// <summary>
-    /// Converts an ExternalPlaylist to a Jellyfin album item.
+    /// Converts an ExternalPlaylist to a Jellyfin playlist item.
     /// </summary>
     public Dictionary<string, object?> ConvertPlaylistToJellyfinItem(ExternalPlaylist playlist)
     {
@@ -538,13 +590,24 @@ public class JellyfinResponseBuilder
         
         var item = new Dictionary<string, object?>
         {
-            ["Id"] = playlist.Id,
             ["Name"] = playlist.Name,
             ["ServerId"] = "allstarr",
-            ["Type"] = "Playlist",
+            ["Id"] = playlist.Id,
+            ["ChannelId"] = (object?)null,
+            ["Genres"] = new string[0], // Playlists aggregate genres from tracks
+            ["RunTimeTicks"] = playlist.Duration * TimeSpan.TicksPerSecond,
             ["IsFolder"] = true,
-            ["AlbumArtist"] = curatorName,
+            ["Type"] = "Playlist",
-            ["Genres"] = new[] { "Playlist" },
+            ["GenreItems"] = new Dictionary<string, object?>[0],
+            ["UserData"] = new Dictionary<string, object>
+            {
+                ["PlaybackPositionTicks"] = 0,
+                ["PlayCount"] = 0,
+                ["IsFavorite"] = false,
+                ["Played"] = false,
+                ["Key"] = playlist.Id,
+                ["ItemId"] = playlist.Id
+            },
             ["ChildCount"] = playlist.TrackCount,
             ["ImageTags"] = new Dictionary<string, string>
             {
@@ -553,20 +616,10 @@ public class JellyfinResponseBuilder
             ["BackdropImageTags"] = new string[0],
             ["ImageBlurHashes"] = new Dictionary<string, object>(),
             ["LocationType"] = "FileSystem",
-            ["MediaType"] = (object?)null,
+            ["MediaType"] = "Audio",
-            ["ChannelId"] = (object?)null,
-            ["CollectionType"] = (object?)null,
             ["ProviderIds"] = new Dictionary<string, string>
             {
                 [playlist.Provider] = playlist.ExternalId
-            },
-            ["UserData"] = new Dictionary<string, object>
-            {
-                ["PlaybackPositionTicks"] = 0,
-                ["PlayCount"] = 0,
-                ["IsFavorite"] = false,
-                ["Played"] = false,
-                ["Key"] = playlist.Id
             }
         };