feat(backend): expose the first cover track ids of playlists and albums

backend/Musify.Application/Albums/GetAlbumById.cs

@@ -17,13 +17,22 @@ namespace Musify.Application.Albums
             var album = await database.UserAlbums
                 .AsNoTracking()
                 .Where(a => a.Id == request.Id)
-                .Select(a => new { Album = a, TrackCount = a.AlbumTracks.Count })
+                .Select(a => new
+                {
+                    Album = a,
+                    TrackCount = a.AlbumTracks.Count,
+                    CoverTrackIds = a.AlbumTracks
+                        .OrderBy(albumTrack => albumTrack.TrackNumber)
+                        .Take(AlbumApplicationResponse.CoverTrackCount)
+                        .Select(albumTrack => albumTrack.TrackId)
+                        .ToList()
+                })
                 .SingleOrDefaultAsync(cancellationToken);
 
             if (album is null)
                 return Error.NotFound();
 
-            return AlbumApplicationResponse.FromEntity(album.Album, album.TrackCount);
+            return AlbumApplicationResponse.FromEntity(album.Album, album.TrackCount, album.CoverTrackIds);
         }
     }
 }

backend/Musify.Application/Albums/GetAlbums.cs

@@ -31,11 +31,20 @@ namespace Musify.Application.Albums
 
             var pagedEntities = await albumsQuery
                 .OrderByDescending(album => album.CreatedAt)
-                .Select(album => new { Album = album, TrackCount = album.AlbumTracks.Count })
+                .Select(album => new
+                {
+                    Album = album,
+                    TrackCount = album.AlbumTracks.Count,
+                    CoverTrackIds = album.AlbumTracks
+                        .OrderBy(albumTrack => albumTrack.TrackNumber)
+                        .Take(AlbumApplicationResponse.CoverTrackCount)
+                        .Select(albumTrack => albumTrack.TrackId)
+                        .ToList()
+                })
                 .ToPagedListAsync(request.PageNumber, request.PageSize, totalCount, cancellationToken);
 
             var pagedAlbums = new StaticPagedList<AlbumApplicationResponse>(
-                pagedEntities.Select(entry => AlbumApplicationResponse.FromEntity(entry.Album, entry.TrackCount)),
+                pagedEntities.Select(entry => AlbumApplicationResponse.FromEntity(entry.Album, entry.TrackCount, entry.CoverTrackIds)),
                 pagedEntities.PageNumber, pagedEntities.PageSize, pagedEntities.TotalItemCount);
 
             return PaginatedResponse<AlbumApplicationResponse>.FromPagedList(pagedAlbums);

backend/Musify.Application/Albums/GetAlbumsByUserId.cs

@@ -31,11 +31,20 @@ namespace Musify.Application.Albums
 
             var pagedEntities = await albumsQuery
                 .OrderByDescending(album => album.CreatedAt)
-                .Select(album => new { Album = album, TrackCount = album.AlbumTracks.Count })
+                .Select(album => new
+                {
+                    Album = album,
+                    TrackCount = album.AlbumTracks.Count,
+                    CoverTrackIds = album.AlbumTracks
+                        .OrderBy(albumTrack => albumTrack.TrackNumber)
+                        .Take(AlbumApplicationResponse.CoverTrackCount)
+                        .Select(albumTrack => albumTrack.TrackId)
+                        .ToList()
+                })
                 .ToPagedListAsync(request.PageNumber, request.PageSize, totalCount, cancellationToken);
 
             var pagedAlbums = new StaticPagedList<AlbumApplicationResponse>(
-                pagedEntities.Select(entry => AlbumApplicationResponse.FromEntity(entry.Album, entry.TrackCount)),
+                pagedEntities.Select(entry => AlbumApplicationResponse.FromEntity(entry.Album, entry.TrackCount, entry.CoverTrackIds)),
                 pagedEntities.PageNumber, pagedEntities.PageSize, pagedEntities.TotalItemCount);
 
             return PaginatedResponse<AlbumApplicationResponse>.FromPagedList(pagedAlbums);

backend/Musify.Application/Albums/Responses/AlbumApplicationResponse.cs

@@ -13,9 +13,15 @@ namespace Musify.Application.Albums.Responses
         string? MediumImageKeyName,
         string? LargeImageKeyName,
         DateTime CreatedAt,
-        DateTime UpdatedAt)
+        DateTime UpdatedAt,
+        IReadOnlyList<Guid> CoverTrackIds)
     {
-        public static AlbumApplicationResponse FromEntity(UserAlbum album, int trackCount)
+        public const int CoverTrackCount = 4;
+
+        public static AlbumApplicationResponse FromEntity(
+            UserAlbum album,
+            int trackCount,
+            IReadOnlyList<Guid>? coverTrackIds = null)
         {
             return new AlbumApplicationResponse(
                 album.Id,
@@ -28,7 +34,8 @@ namespace Musify.Application.Albums.Responses
                 album.Pictures?.MediumName,
                 album.Pictures?.LargeName,
                 album.CreatedAt,
-                album.UpdatedAt);
+                album.UpdatedAt,
+                coverTrackIds ?? []);
         }
     }
 }

backend/Musify.Application/Albums/SaveYouTubeAlbum.cs

@@ -89,14 +89,21 @@ namespace Musify.Application.Albums
                 return Error.Failure(description: $"Failed to save album {request.AlbumId}");
             }
 
-            var trackCount = await database.AlbumHasTracks
+            var albumTracks = database.AlbumHasTracks
                 .AsNoTracking()
-                .CountAsync(albumTrack => albumTrack.AlbumId == album.Id, cancellationToken);
+                .Where(albumTrack => albumTrack.AlbumId == album.Id);
+
+            var trackCount = await albumTracks.CountAsync(cancellationToken);
+            var coverTrackIds = await albumTracks
+                .OrderBy(albumTrack => albumTrack.TrackNumber)
+                .Take(AlbumApplicationResponse.CoverTrackCount)
+                .Select(albumTrack => albumTrack.TrackId)
+                .ToListAsync(cancellationToken);
 
             logger.LogInformation("Saved YouTube album {AlbumId} as {AlbumGuid} with {TrackCount} tracks",
                 request.AlbumId, album.Id, trackCount);
 
-            return AlbumApplicationResponse.FromEntity(album, trackCount);
+            return AlbumApplicationResponse.FromEntity(album, trackCount, coverTrackIds);
         }
 
         private static string Truncate(string value, int maxLength) =>

backend/Musify.Application/Albums/UpdateAlbum.cs

@@ -53,11 +53,18 @@ namespace Musify.Application.Albums
                 return Error.Failure(description: $"Failed to update album {request.AlbumId}");
             }
 
-            var trackCount = await database.AlbumHasTracks
+            var albumTracks = database.AlbumHasTracks
                 .AsNoTracking()
-                .CountAsync(albumTrack => albumTrack.AlbumId == album.Id, cancellationToken);
+                .Where(albumTrack => albumTrack.AlbumId == album.Id);
 
-            return AlbumApplicationResponse.FromEntity(album, trackCount);
+            var trackCount = await albumTracks.CountAsync(cancellationToken);
+            var coverTrackIds = await albumTracks
+                .OrderBy(albumTrack => albumTrack.TrackNumber)
+                .Take(AlbumApplicationResponse.CoverTrackCount)
+                .Select(albumTrack => albumTrack.TrackId)
+                .ToListAsync(cancellationToken);
+
+            return AlbumApplicationResponse.FromEntity(album, trackCount, coverTrackIds);
         }
     }
 }

backend/Musify.Application/PlayLists/GetPlayListById.cs

@@ -14,16 +14,24 @@ namespace Musify.Application.PlayLists
     {
         public async ValueTask<ErrorOr<PlayListApplicationResponse>> Handle(GetPlayListByIdQuery request, CancellationToken cancellationToken)
         {
-            var playList = await database.PlayLists
+            var entry = await database.PlayLists
                 .AsNoTracking()
                 .Where(p => p.Id == request.Id)
-                .Select(p => PlayListApplicationResponse.FromEntity(p))
+                .Select(p => new
+                {
+                    PlayList = p,
+                    CoverTrackIds = p.PlayListTracks
+                        .OrderBy(plt => plt.Position)
+                        .Take(PlayListApplicationResponse.CoverTrackCount)
+                        .Select(plt => plt.TrackId)
+                        .ToList()
+                })
                 .SingleOrDefaultAsync(cancellationToken);
 
-            if (playList is null)
+            if (entry is null)
                 return Error.NotFound();
 
-            return playList;
+            return PlayListApplicationResponse.FromEntity(entry.PlayList, entry.CoverTrackIds);
         }
     }
 }

backend/Musify.Application/PlayLists/GetPlayLists.cs

@@ -2,6 +2,7 @@ using ErrorOr;
 using Microsoft.EntityFrameworkCore;
 using Musify.Application.Shared;
 using Musify.Application.PlayLists.Responses;
+using X.PagedList;
 using X.PagedList.EF;
 using Mediator;
 using Musify.Application.Contracts;
@@ -18,12 +19,24 @@ namespace Musify.Application.PlayLists
         {
             var totalCount = await database.PlayLists.CountAsync(cancellationToken);
 
-            var pagedPlayLists = await database.PlayLists
+            var pagedEntities = await database.PlayLists
                 .AsNoTracking()
                 .OrderBy(p => p.Id)
-                .Select(p => PlayListApplicationResponse.FromEntity(p))
+                .Select(p => new
+                {
+                    PlayList = p,
+                    CoverTrackIds = p.PlayListTracks
+                        .OrderBy(plt => plt.Position)
+                        .Take(PlayListApplicationResponse.CoverTrackCount)
+                        .Select(plt => plt.TrackId)
+                        .ToList()
+                })
                 .ToPagedListAsync(request.PageNumber, request.PageSize, totalCount, cancellationToken);
 
+            var pagedPlayLists = new StaticPagedList<PlayListApplicationResponse>(
+                pagedEntities.Select(entry => PlayListApplicationResponse.FromEntity(entry.PlayList, entry.CoverTrackIds)),
+                pagedEntities.PageNumber, pagedEntities.PageSize, pagedEntities.TotalItemCount);
+
             return PaginatedResponse<PlayListApplicationResponse>.FromPagedList(pagedPlayLists);
         }
     }

backend/Musify.Application/PlayLists/GetPlayListsByUserId.cs

@@ -2,6 +2,7 @@ using ErrorOr;
 using Microsoft.EntityFrameworkCore;
 using Musify.Application.Shared;
 using Musify.Application.PlayLists.Responses;
+using X.PagedList;
 using X.PagedList.EF;
 using Mediator;
 using Musify.Application.Contracts;
@@ -32,11 +33,23 @@ namespace Musify.Application.PlayLists
 
             var totalCount = await playListsQuery.CountAsync(cancellationToken);
 
-            var pagedPlayLists = await playListsQuery
+            var pagedEntities = await playListsQuery
                 .OrderBy(p => p.CreatedAt)
-                .Select(p => PlayListApplicationResponse.FromEntity(p))
+                .Select(p => new
+                {
+                    PlayList = p,
+                    CoverTrackIds = p.PlayListTracks
+                        .OrderBy(plt => plt.Position)
+                        .Take(PlayListApplicationResponse.CoverTrackCount)
+                        .Select(plt => plt.TrackId)
+                        .ToList()
+                })
                 .ToPagedListAsync(request.PageNumber, request.PageSize, totalCount, cancellationToken);
 
+            var pagedPlayLists = new StaticPagedList<PlayListApplicationResponse>(
+                pagedEntities.Select(entry => PlayListApplicationResponse.FromEntity(entry.PlayList, entry.CoverTrackIds)),
+                pagedEntities.PageNumber, pagedEntities.PageSize, pagedEntities.TotalItemCount);
+
             return PaginatedResponse<PlayListApplicationResponse>.FromPagedList(pagedPlayLists);
         }
     }

backend/Musify.Application/PlayLists/Responses/PlayListApplicationResponse.cs

@@ -1,4 +1,4 @@
-using Musify.Domain.Entities;
+using Musify.Domain.Entities;
 
 namespace Musify.Application.PlayLists.Responses
 {
@@ -10,9 +10,14 @@ namespace Musify.Application.PlayLists.Responses
         string? MediumImageKeyName,
         string? LargeImageKeyName,
         DateTime CreatedAt,
-        DateTime UpdatedAt)
+        DateTime UpdatedAt,
+        IReadOnlyList<Guid> CoverTrackIds)
     {
-        public static PlayListApplicationResponse FromEntity(PlayList playList)
+        public const int CoverTrackCount = 4;
+
+        public static PlayListApplicationResponse FromEntity(
+            PlayList playList,
+            IReadOnlyList<Guid>? coverTrackIds = null)
         {
             return new PlayListApplicationResponse(
                 playList.Id,
@@ -22,7 +27,8 @@ namespace Musify.Application.PlayLists.Responses
                 playList.Pictures?.MediumName,
                 playList.Pictures?.LargeName,
                 playList.CreatedAt,
-                playList.UpdatedAt);
+                playList.UpdatedAt,
+                coverTrackIds ?? []);
         }
     }
 }

backend/Musify.Application/PlayLists/UpdatePlayList.cs

@@ -93,8 +93,16 @@ namespace Musify.Application.PlayLists
                 return Error.Failure(description: $"Failed to update playlist {playListEntity.Id}");
             }
 
+            var coverTrackIds = await database.PlayListHasTracks
+                .AsNoTracking()
+                .Where(plt => plt.PlayListId == playListEntity.Id)
+                .OrderBy(plt => plt.Position)
+                .Take(PlayListApplicationResponse.CoverTrackCount)
+                .Select(plt => plt.TrackId)
+                .ToListAsync(cancellationToken);
+
             logger.LogInformation("Updated playlist {PlayListId}", playListEntity.Id);
-            return PlayListApplicationResponse.FromEntity(playListEntity);
+            return PlayListApplicationResponse.FromEntity(playListEntity, coverTrackIds);
         }
 
         async Task<ErrorOr<Success>> PublishUpdatePlayListPictureSourceEventAsync(