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YandexMusic.API/Requests/Playlist/YPlaylistChangeBuilder.cs

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+using System.Net;
+
+using YandexMusic.API.Common;
+using YandexMusic.API.Models.Common;
+using YandexMusic.API.Models.Playlist;
+using YandexMusic.API.Requests.Common;
+using YandexMusic.API.Requests.Common.Attributes;
+
+namespace YandexMusic.API.Requests.Playlist
+{
+    [YApiRequest(WebRequestMethods.Http.Post, "users/{uid}/playlists/{kind}/change")]
+    public class YPlaylistChangeBuilder : YRequestBuilder<YResponse<YPlaylist>, (YPlaylist playlist, IEnumerable<YPlaylistChange> changes)>
+    {
+        public YPlaylistChangeBuilder(YandexMusicApi yandex, AuthStorage auth) : base(yandex, auth)
+        {
+        }
+
+        protected override Dictionary<string, string> GetSubstitutions((YPlaylist playlist, IEnumerable<YPlaylistChange> changes) tuple)
+        {
+            return new Dictionary<string, string> {
+                { "uid", storage.User.Uid },
+                { "kind", tuple.playlist.Kind }
+            };
+        }
+
+        protected override HttpContent GetContent((YPlaylist playlist, IEnumerable<YPlaylistChange> changes) tuple)
+        {
+            return new FormUrlEncodedContent(new Dictionary<string, string> {
+                { "kind", tuple.playlist.Kind },
+                { "revision", tuple.playlist.Revision.ToString() },
+                { "diff", SerializeJson(tuple.changes) }
+            });
+        }
+    }
+}