Make lobby song update occur at round end (#19303)

Content.Client/Audio/BackgroundAudioSystem.cs

@@ -34,7 +34,7 @@ public sealed class BackgroundAudioSystem : EntitySystem
 
         _client.PlayerLeaveServer += OnLeave;
 
-        _gameTicker.LobbyStatusUpdated += LobbySongReceived;
+        _gameTicker.LobbySongUpdated += LobbySongUpdated;
     }
 
     public override void Shutdown()
@@ -48,7 +48,7 @@ public sealed class BackgroundAudioSystem : EntitySystem
 
         _client.PlayerLeaveServer -= OnLeave;
 
-        _gameTicker.LobbyStatusUpdated -= LobbySongReceived;
+        _gameTicker.LobbySongUpdated -= LobbySongUpdated;
 
         EndLobbyMusic();
     }
@@ -95,17 +95,9 @@ public sealed class BackgroundAudioSystem : EntitySystem
         }
     }
 
-    private void LobbySongReceived()
+    private void LobbySongUpdated()
     {
-        if (_lobbyStream != null) //Toggling Ready status fires this method. This check ensures we only start the lobby music if it's not playing.
-        {
-            return;
-        }
-
-        if (_stateManager.CurrentState is LobbyState)
-        {
-            StartLobbyMusic();
-        }
+        RestartLobbyMusic();
     }
 
     public void RestartLobbyMusic()

Content.Client/GameTicking/Managers/ClientGameTicker.cs

@@ -1,4 +1,3 @@
-using Content.Client.Audio;
 using Content.Client.Gameplay;
 using Content.Client.Lobby;
 using Content.Client.RoundEnd;
@@ -8,7 +7,6 @@ using Content.Shared.GameWindow;
 using JetBrains.Annotations;
 using Robust.Client.Graphics;
 using Robust.Client.State;
-using Robust.Shared.Audio;
 using Robust.Shared.Configuration;
 using Robust.Shared.Player;
 using Robust.Shared.Utility;
@@ -21,7 +19,6 @@ namespace Content.Client.GameTicking.Managers
         [Dependency] private readonly IStateManager _stateManager = default!;
         [Dependency] private readonly IEntityManager _entityManager = default!;
         [Dependency] private readonly IConfigurationManager _configManager = default!;
-        [Dependency] private readonly BackgroundAudioSystem _backgroundAudio = default!;
         [Dependency] private readonly SharedAudioSystem _audio = default!;
 
         [ViewVariables] private bool _initialized;
@@ -49,6 +46,7 @@ namespace Content.Client.GameTicking.Managers
 
         public event Action? InfoBlobUpdated;
         public event Action? LobbyStatusUpdated;
+        public event Action? LobbySongUpdated;
         public event Action? LobbyLateJoinStatusUpdated;
         public event Action<IReadOnlyDictionary<EntityUid, Dictionary<string, uint?>>>? LobbyJobsAvailableUpdated;
 
@@ -73,6 +71,16 @@ namespace Content.Client.GameTicking.Managers
             _initialized = true;
         }
 
+        public void SetLobbySong(string? song, bool forceUpdate = false)
+        {
+            var updated = song != LobbySong;
+
+            LobbySong = song;
+
+            if (updated || forceUpdate)
+                LobbySongUpdated?.Invoke();
+        }
+
         private void LateJoinStatus(TickerLateJoinStatusEvent message)
         {
             DisallowedLateJoin = message.Disallowed;
@@ -97,7 +105,7 @@ namespace Content.Client.GameTicking.Managers
             RoundStartTimeSpan = message.RoundStartTimeSpan;
             IsGameStarted = message.IsRoundStarted;
             AreWeReady = message.YouAreReady;
-            LobbySong = message.LobbySong;
+            SetLobbySong(message.LobbySong);
             LobbyBackground = message.LobbyBackground;
             Paused = message.Paused;
 
@@ -124,12 +132,8 @@ namespace Content.Client.GameTicking.Managers
 
         private void RoundEnd(RoundEndMessageEvent message)
         {
-            if (message.LobbySong != null)
-            {
-                LobbySong = message.LobbySong;
-                _backgroundAudio.StartLobbyMusic();
-            }
-
+            // Force an update in the event of this song being the same as the last.
+            SetLobbySong(message.LobbySong, true);
             RestartSound = message.RestartSound;
 
             // Don't open duplicate windows (mainly for replays).

Content.Server/GameTicking/GameTicker.RoundFlow.cs

@@ -323,6 +323,12 @@ namespace Content.Server.GameTicking
 
             RunLevel = GameRunLevel.PostRound;
 
+            // The lobby song is set here instead of in RestartRound,
+            // because ShowRoundEndScoreboard triggers the start of the music playing
+            // at the end of a round, and this needs to be set before RestartRound
+            // in order for the lobby song status display to be accurate.
+            LobbySong = _robustRandom.Pick(_lobbyMusicCollection.PickFiles).ToString();
+
             ShowRoundEndScoreboard(text);
         }
 
@@ -453,7 +459,6 @@ namespace Content.Server.GameTicking
             PlayersJoinedRoundNormally = 0;
 
             RunLevel = GameRunLevel.PreRoundLobby;
-            LobbySong = _robustRandom.Pick(_lobbyMusicCollection.PickFiles).ToString();
             RandomizeLobbyBackground();
             ResettingCleanup();
             IncrementRoundNumber();