Add shared pagination, projections and ownership helpers; simplify query and command handlers

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

@@ -18,7 +18,7 @@ public record AlbumApplicationResponse(
     DateTime UpdatedAt,
     IReadOnlyList<Guid> CoverTrackIds)
 {
-    public const int CoverTrackCount = 4;
+    public const int CoverTrackCount = AlbumProjections.CoverTrackCount;
 
     public static AlbumApplicationResponse FromEntity(
         Album album,

backend/Core/Musify.Application/Albums/Responses/AlbumProjections.cs

@@ -0,0 +1,31 @@
+using Musify.Domain.Entities;
+using Musify.Domain.ValueObjects;
+
+namespace Musify.Application.Albums.Responses;
+
+public static class AlbumProjections
+{
+    public const int CoverTrackCount = 4;
+
+    public static IQueryable<Album> Active(this IQueryable<Album> query) =>
+        query.Where(album => album.LifeCycleStatus == LifeCycleStatus.Active);
+
+    public static IQueryable<AlbumApplicationResponse> SelectResponse(this IQueryable<Album> query) =>
+        query.Select(album => new AlbumApplicationResponse(
+            album.Id,
+            album.Title,
+            album.Description,
+            album.ReleaseYear,
+            album.OwnerUserId,
+            album.AlbumTracks.Count,
+            album.Pictures!.SmallName,
+            album.Pictures!.MediumName,
+            album.Pictures!.LargeName,
+            album.CreatedAt,
+            album.UpdatedAt,
+            album.AlbumTracks
+                .OrderBy(albumTrack => albumTrack.TrackNumber)
+                .Take(CoverTrackCount)
+                .Select(albumTrack => albumTrack.TrackId)
+                .ToList()));
+}

backend/Core/Musify.Application/Albums/Responses/AlbumSearchItemResponse.cs

@@ -1,6 +0,0 @@
-namespace Musify.Application.Albums.Responses;
-
-public record AlbumSearchItemResponse(AlbumApplicationResponse Album)
-{
-    public static AlbumSearchItemResponse FromAlbum(AlbumApplicationResponse album) => new(album);
-}

backend/Core/Musify.Application/Albums/Responses/AlbumsSearchResponse.cs

@@ -1,11 +0,0 @@
-namespace Musify.Application.Albums.Responses;
-
-
-public record AlbumsSearchResponse(
-    IReadOnlyList<AlbumSearchItemResponse> Items,
-    int PageNumber,
-    int PageSize,
-    int PageCount,
-    int TotalItemCount,
-    bool HasPreviousPage,
-    bool HasNextPage);