using System; using Jellyfin.Data.Enums; using MediaBrowser.Controller.Entities; using MediaBrowser.Controller.Entities.Audio; using MediaBrowser.Controller.Sorting; using MediaBrowser.Model.Querying; namespace Emby.Server.Implementations.Sorting { /// <summary> /// Allows comparing artists of albums. Only the first artist of each album is considered. /// </summary> public class AlbumArtistComparer : IBaseItemComparer { /// <summary> /// Gets the item type this comparer compares. /// </summary> public ItemSortBy Type => ItemSortBy.AlbumArtist; /// <summary> /// Compares the specified arguments on their primary artist. /// </summary> /// <param name="x">First item to compare.</param> /// <param name="y">Second item to compare.</param> /// <returns>Zero if equal, else negative or positive number to indicate order.</returns> public int Compare(BaseItem? x, BaseItem? y) { return string.Compare(GetFirstAlbumArtist(x), GetFirstAlbumArtist(y), StringComparison.OrdinalIgnoreCase); } private static string? GetFirstAlbumArtist(BaseItem? x) { if (x is IHasAlbumArtist audio && audio.AlbumArtists.Count != 0) { return audio.AlbumArtists[0]; } return null; } } }