backend/Musify.Application/Services/YouTubeTrackProvisioner.cs

@@ -8,7 +8,7 @@ using Musify.Domain.ValueObjects;
 
 namespace Musify.Application.Services;
 
-public sealed record YouTubeTrackProvision(Track Track, bool Created, YouTubeSongResult? Song);
+public sealed record YouTubeTrackProvision(Track Track, YouTubeSongResult? Song);
 
 public sealed class YouTubeTrackProvisioner(
     IDatabase database,
@@ -26,7 +26,7 @@ public sealed class YouTubeTrackProvisioner(
     {
         var existing = await FindAsync(videoId, cancellationToken);
         if (existing is not null)
-            return new YouTubeTrackProvision(existing, Created: false, Song: null);
+            return new YouTubeTrackProvision(existing, Song: null);
 
         var songResult = await youTubeMusicService.GetSongAsync(videoId, cancellationToken);
         if (songResult.IsError)
@@ -81,7 +81,7 @@ public sealed class YouTubeTrackProvisioner(
         {
             await database.SaveChangesAsync(cancellationToken);
             logger.LogInformation("Created YouTube track {VideoId} ({TrackId})", videoId, track.Id);
-            return new YouTubeTrackProvision(track, Created: true, Song: song);
+            return new YouTubeTrackProvision(track, Song: song);
         }
         catch (DbUpdateException)
         {
@@ -92,7 +92,7 @@ public sealed class YouTubeTrackProvisioner(
                 logger.LogWarning("YouTube track {VideoId} creation raced but could not be refetched", videoId);
                 return Error.Conflict(description: "The track was just created by another request. Retry the operation.");
             }
-            return new YouTubeTrackProvision(refetched, Created: false, Song: null);
+            return new YouTubeTrackProvision(refetched, Song: null);
         }
     }
 
@@ -108,6 +108,30 @@ public sealed class YouTubeTrackProvisioner(
         if (existing is not null)
             return existing;
 
+        if (byExternalId)
+        {
+            var adoptable = await database.Artists
+                .SingleOrDefaultAsync(a => a.ExternalId == null && a.UserId == null && a.NormalizedName == normalized, cancellationToken);
+            if (adoptable is not null)
+            {
+                var previousName = adoptable.Name;
+                adoptable.ExternalId = reference.Id;
+                adoptable.Name = name;
+
+                try
+                {
+                    await database.SaveChangesAsync(cancellationToken);
+                    return adoptable;
+                }
+                catch (DbUpdateException)
+                {
+                    adoptable.ExternalId = null;
+                    adoptable.Name = previousName;
+                    return await database.Artists.SingleAsync(a => a.ExternalId == reference.Id, cancellationToken);
+                }
+            }
+        }
+
         var artist = new Artist
         {
             Name = name,

backend/Musify.Application/Users/SyncUser.cs

@@ -47,6 +47,14 @@ namespace Musify.Application.Users
             user.SecondName = request.SecondName;
             user.ProfilePictureUrl = request.ProfilePictureUrl;
 
+            var artist = await database.Artists
+                .SingleOrDefaultAsync(a => a.UserId == request.Id, cancellationToken);
+            if (artist is not null)
+            {
+                artist.Name = request.Name;
+                artist.NormalizedName = request.Name.ToUpperInvariant();
+            }
+
             var written = await database.SaveChangesAsync(cancellationToken);
             if (written > 0)
                 logger.LogInformation("Synced profile for user {UserId}", request.Id);

backend/Musify.Infrastructure/Persistence/Migrations/20260716214752_AddArtistsAndTrackOwnership.cs

@@ -108,6 +108,11 @@ namespace Musify.Infrastructure.Persistence.Migrations
                 WHERE t."Source" = 0 AND ut."TrackId" = t."Id";
                 """);
 
+            migrationBuilder.Sql(
+                """
+                DELETE FROM "Tracks" WHERE "Source" = 0 AND "OwnerUserId" IS NULL;
+                """);
+
             migrationBuilder.Sql(
                 """
                 INSERT INTO "Artists" ("Id", "Name", "NormalizedName", "UserId", "ExternalId", "CreatedAt", "UpdatedAt")
@@ -120,7 +125,12 @@ namespace Musify.Infrastructure.Persistence.Migrations
                 """
                 INSERT INTO "Artists" ("Id", "Name", "NormalizedName", "UserId", "ExternalId", "CreatedAt", "UpdatedAt")
                 SELECT gen_random_uuid(), s."Artist", upper(s."Artist"), NULL, NULL, now(), now()
-                FROM (SELECT DISTINCT "Artist" FROM "Tracks" WHERE "Source" = 1 AND "Artist" IS NOT NULL) s;
+                FROM (
+                    SELECT DISTINCT ON (upper("Artist")) "Artist"
+                    FROM "Tracks"
+                    WHERE "Source" = 1 AND "Artist" IS NOT NULL
+                    ORDER BY upper("Artist"), "Artist"
+                ) s;
                 """);
 
             migrationBuilder.Sql(
@@ -135,7 +145,7 @@ namespace Musify.Infrastructure.Persistence.Migrations
                 """
                 INSERT INTO "TrackArtist" ("TrackId", "ArtistId", "Position")
                 SELECT t."Id", a."Id", 0 FROM "Tracks" t
-                JOIN "Artists" a ON a."UserId" IS NULL AND a."ExternalId" IS NULL AND a."Name" = t."Artist"
+                JOIN "Artists" a ON a."UserId" IS NULL AND a."ExternalId" IS NULL AND a."NormalizedName" = upper(t."Artist")
                 WHERE t."Source" = 1 AND t."Artist" IS NOT NULL;
                 """);