feat(backend): add the album use cases

Create, update, delete and list albums, plus adding and removing their tracks, mirroring the playlist handlers. Only tracks the user uploaded can go into an album, and removing one renumbers the rest so the tracklist stays 1..n.
2026-07-20 20:10:45 +02:00
parent 8e561f5b2a
commit 712f130e1d
10 changed files with 518 additions and 0 deletions
@@ -0,0 +1,63 @@
+using ErrorOr;
+using Mediator;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Logging;
+using Musify.Application.Albums.Responses;
+using Musify.Application.Contracts;
+
+namespace Musify.Application.Albums
+{
+    public record UpdateAlbumCommand(
+        long UserId,
+        Guid AlbumId,
+        string Title,
+        string? Description,
+        int? ReleaseYear)
+        : ICommand<ErrorOr<AlbumApplicationResponse>>;
+
+    public class UpdateAlbumCommandHandler(
+        IDatabase database,
+        ILogger<UpdateAlbumCommandHandler> logger)
+        : ICommandHandler<UpdateAlbumCommand, ErrorOr<AlbumApplicationResponse>>
+    {
+        public async ValueTask<ErrorOr<AlbumApplicationResponse>> Handle(UpdateAlbumCommand request, CancellationToken cancellationToken)
+        {
+            var album = await database.UserAlbums
+                .SingleOrDefaultAsync(a => a.Id == request.AlbumId, cancellationToken);
+            if (album is null)
+            {
+                logger.LogInformation("Album {AlbumId} not found", request.AlbumId);
+                return Error.NotFound();
+            }
+
+            if (album.OwnerUserId != request.UserId)
+            {
+                logger.LogWarning("Album {AlbumId} does not belong to user {UserId}", request.AlbumId, request.UserId);
+                return Error.Unauthorized();
+            }
+
+            var title = request.Title.Trim();
+
+            album.Title = title;
+            album.NormalizedTitle = title.ToUpperInvariant();
+            album.Description = request.Description;
+            album.ReleaseYear = request.ReleaseYear;
+
+            try
+            {
+                await database.SaveChangesAsync(cancellationToken);
+            }
+            catch (Exception exception)
+            {
+                logger.LogError(exception, "Failed to update album {AlbumId}", request.AlbumId);
+                return Error.Failure(description: $"Failed to update album {request.AlbumId}");
+            }
+
+            var trackCount = await database.AlbumHasTracks
+                .AsNoTracking()
+                .CountAsync(albumTrack => albumTrack.AlbumId == album.Id, cancellationToken);
+
+            return AlbumApplicationResponse.FromEntity(album, trackCount);
+        }
+    }
+}