From 14bc2db98d44f351308bb670bc992d332238a585 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gerg=C5=91=20Gel=C3=B3czi?= <geloczigeri@gmail.com>
Date: Sun, 19 Dec 2021 21:42:27 +0100
Subject: [PATCH] Add to playlist, remove from playlist

---
 .../AudioStationConnector_Tests.cs            | 30 ++++++++++++++++---
 .../AudioStationClient.Playlist.cs            | 30 ++++++++++++++++++-
 2 files changed, 55 insertions(+), 5 deletions(-)

diff --git a/SynologyDotNet.AudioStation.IntegrationTest/AudioStationConnector_Tests.cs b/SynologyDotNet.AudioStation.IntegrationTest/AudioStationConnector_Tests.cs
index 13572aa..f8fae52 100644
--- a/SynologyDotNet.AudioStation.IntegrationTest/AudioStationConnector_Tests.cs
+++ b/SynologyDotNet.AudioStation.IntegrationTest/AudioStationConnector_Tests.cs
@@ -363,7 +363,7 @@ public async Task GetSongById()
         }
 
         [TestMethod]
-        public async Task ListPlaylists()
+        public async Task Playlist_List()
         {
             var response = await AudioStation.ListPlaylistsAsync(TestPageSize, 0);
             Assert.IsTrue(response.Success);
@@ -372,9 +372,9 @@ public async Task ListPlaylists()
         }
 
         [TestMethod]
-        public async Task GetPlaylist()
+        public async Task Playlist_Get()
         {
-            var playlist = await AudioStation.GetPlaylistAsync(TestPageSize, 0, TestPlaylist.ID, SongQueryAdditional.None);
+            var playlist = await AudioStation.GetPlaylistAsync(TestPageSize, 0, TestPlaylist.ID);
             Assert.IsTrue(playlist.Success);
             Assert.IsFalse(string.IsNullOrEmpty(playlist.Data.ID));
             Assert.IsTrue(playlist.Data.Additional.Songs.Length > 0);
@@ -385,7 +385,7 @@ public async Task GetPlaylist()
         }
 
         [TestMethod]
-        public async Task GetPlaylist_SongDetails()
+        public async Task Playlist_GetWithSongDetails()
         {
             var playlist = await AudioStation.GetPlaylistAsync(TestPageSize, 0, TestPlaylist.ID, SongQueryAdditional.All);
             Assert.IsTrue(playlist.Success);
@@ -397,6 +397,28 @@ public async Task GetPlaylist_SongDetails()
             }
         }
 
+        [TestMethod]
+        public async Task Playlist_AddAndRemoveSong()
+        {
+            // Add test song to playlist
+            var response = await AudioStation.AddSongsToPlaylist(TestPlaylist.ID, TestSong.ID);
+            Assert.IsTrue(response.Success);
+
+            // Get all songs on playlist
+            var playlist = await AudioStation.GetPlaylistAsync(TestPageSize, 0, TestPlaylist.ID);
+            Assert.IsTrue(playlist.Success);
+            Assert.IsTrue(playlist.Data.Additional.Songs.Any(x => x.ID == TestSong.ID));
+
+            // Remove the test song from the playlist
+            var testSongPlaylistIndex = playlist.Data.Additional.Songs.Select((song, index) => (song, index)).First(x => x.song.ID == TestSong.ID).index;
+            response = await AudioStation.RemoveSongsFromPlaylist(TestPlaylist.ID, testSongPlaylistIndex, 1);
+
+            // Check
+            playlist = await AudioStation.GetPlaylistAsync(TestPageSize, 0, TestPlaylist.ID);
+            Assert.IsTrue(playlist.Success);
+            Assert.IsFalse(playlist.Data.Additional.Songs.Any(x => x.ID == TestSong.ID));
+        }
+
         [TestMethod]
         public async Task GetFileTags()
         {
diff --git a/SynologyDotNet.AudioStation/AudioStationClient.Playlist.cs b/SynologyDotNet.AudioStation/AudioStationClient.Playlist.cs
index d9aa31a..5a35a39 100644
--- a/SynologyDotNet.AudioStation/AudioStationClient.Playlist.cs
+++ b/SynologyDotNet.AudioStation/AudioStationClient.Playlist.cs
@@ -30,7 +30,7 @@ public async Task<ApiListRessponse<PlaylistList>> ListPlaylistsAsync(int limit,
         /// <param name="id">The identifier.</param>
         /// <param name="additionalFields">Additional fields to load.</param>
         /// <returns></returns>
-        public async Task<ApiDataResponse<Playlist>> GetPlaylistAsync(int limit, int offset, string id, SongQueryAdditional additionalFields)
+        public async Task<ApiDataResponse<Playlist>> GetPlaylistAsync(int limit, int offset, string id, SongQueryAdditional additionalFields = SongQueryAdditional.None)
         {
             var args = new List<(string, object)>();
             args.Add(GetLibraryArg());
@@ -59,5 +59,33 @@ public async Task<ApiDataResponse<Playlist>> GetPlaylistAsync(int limit, int off
             var playlists = await Client.QueryListAsync<ApiListRessponse<PlaylistList>>(SYNO_AudioStation_Playlist, "getinfo", limit, offset, args.ToArray());
             return new ApiDataResponse<Playlist>(playlists, playlists.Data?.Playlists?.FirstOrDefault() ?? default);
         }
+
+        public async Task<ApiResponse> AddSongsToPlaylist(string id, params string[] songIds)
+        {
+            return await Client.QueryObjectAsync<ApiResponse>(SYNO_AudioStation_Playlist, "updatesongs",
+                ("id", id),
+                ("offset", -1),
+                ("limit", 0),
+                ("songs", string.Join(",", songIds))
+            );
+        }
+
+        /// <summary>
+        /// Removes the selected song range from the specified playlist.
+        /// The Playlist API does NOT support removing songs by ID directly, you must query the playlist first.
+        /// </summary>
+        /// <param name="id">The identifier of the Playlist.</param>
+        /// <param name="startIndex">The index of the first song to be deleted.</param>
+        /// <param name="count">The count of songs to be removed from start index.</param>
+        public async Task<ApiResponse> RemoveSongsFromPlaylist(string id, int startIndex, int count)
+        {
+            // The Playlist API does NOT support removing songs by ID, it is using the "offset" and "limit" parameters to define the range to remove.
+            return await Client.QueryObjectAsync<ApiResponse>(SYNO_AudioStation_Playlist, "updatesongs",
+                ("id", id),
+                ("offset", startIndex),
+                ("limit", count),
+                ("songs", string.Empty)
+            );
+        }
     }
 }