Revert "Merge pull request #20145 from smoogipoo/multiple-countdowns"

This reverts commit 13d9b2188b, reversing
changes made to d463bd2f3f.

osu.Game.Tests/Visual/Multiplayer/TestSceneMatchStartControl.cs

@@ -91,7 +91,8 @@ namespace osu.Game.Tests.Visual.Multiplayer
                                          break;
 
                                      case StopCountdownRequest:
-                                         clearRoomCountdown();
+                                         multiplayerRoom.Countdown = null;
+                                         raiseRoomUpdated();
                                          break;
                                  }
                              });
@@ -243,14 +244,14 @@ namespace osu.Game.Tests.Visual.Multiplayer
             });
 
             AddStep("start countdown", () => multiplayerClient.Object.SendMatchRequest(new StartMatchCountdownRequest { Duration = TimeSpan.FromMinutes(1) }).WaitSafely());
-            AddUntilStep("countdown started", () => multiplayerRoom.ActiveCountdowns.Any());
+            AddUntilStep("countdown started", () => multiplayerRoom.Countdown != null);
 
             AddStep("transfer host to local user", () => transferHost(localUser));
             AddUntilStep("local user is host", () => multiplayerRoom.Host?.Equals(multiplayerClient.Object.LocalUser) == true);
 
             ClickButtonWhenEnabled<MultiplayerReadyButton>();
             checkLocalUserState(MultiplayerUserState.Ready);
-            AddAssert("countdown still active", () => multiplayerRoom.ActiveCountdowns.Any());
+            AddAssert("countdown still active", () => multiplayerRoom.Countdown != null);
         }
 
         [Test]
@@ -391,13 +392,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
         private void setRoomCountdown(TimeSpan duration)
         {
-            multiplayerRoom.ActiveCountdowns.Add(new MatchStartCountdown { TimeRemaining = duration });
-            raiseRoomUpdated();
-        }
-
-        private void clearRoomCountdown()
-        {
-            multiplayerRoom.ActiveCountdowns.Clear();
+            multiplayerRoom.Countdown = new MatchStartCountdown { TimeRemaining = duration };
             raiseRoomUpdated();
         }
 

osu.Game/Online/Multiplayer/Countdown/CountdownChangedEvent.cs

@@ -0,0 +1,20 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using MessagePack;
+
+namespace osu.Game.Online.Multiplayer.Countdown
+{
+    /// <summary>
+    /// Indicates a change to the <see cref="MultiplayerRoom"/>'s countdown.
+    /// </summary>
+    [MessagePackObject]
+    public class CountdownChangedEvent : MatchServerEvent
+    {
+        /// <summary>
+        /// The new countdown.
+        /// </summary>
+        [Key(0)]
+        public MultiplayerCountdown? Countdown { get; set; }
+    }
+}

osu.Game/Online/Multiplayer/Countdown/CountdownStartedEvent.cs

@@ -1,28 +0,0 @@
-// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
-// See the LICENCE file in the repository root for full licence text.
-
-using MessagePack;
-using Newtonsoft.Json;
-
-namespace osu.Game.Online.Multiplayer.Countdown
-{
-    /// <summary>
-    /// Indicates that a countdown started in the <see cref="MultiplayerRoom"/>.
-    /// </summary>
-    [MessagePackObject]
-    public class CountdownStartedEvent : MatchServerEvent
-    {
-        /// <summary>
-        /// The countdown that was started.
-        /// </summary>
-        [Key(0)]
-        public readonly MultiplayerCountdown Countdown;
-
-        [JsonConstructor]
-        [SerializationConstructor]
-        public CountdownStartedEvent(MultiplayerCountdown countdown)
-        {
-            Countdown = countdown;
-        }
-    }
-}

osu.Game/Online/Multiplayer/Countdown/CountdownStoppedEvent.cs

@@ -1,28 +0,0 @@
-// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
-// See the LICENCE file in the repository root for full licence text.
-
-using MessagePack;
-using Newtonsoft.Json;
-
-namespace osu.Game.Online.Multiplayer.Countdown
-{
-    /// <summary>
-    /// Indicates that a countdown was stopped in the <see cref="MultiplayerRoom"/>.
-    /// </summary>
-    [MessagePackObject]
-    public class CountdownStoppedEvent : MatchServerEvent
-    {
-        /// <summary>
-        /// The identifier of the countdown that was stopped.
-        /// </summary>
-        [Key(0)]
-        public readonly int ID;
-
-        [JsonConstructor]
-        [SerializationConstructor]
-        public CountdownStoppedEvent(int id)
-        {
-            ID = id;
-        }
-    }
-}

osu.Game/Online/Multiplayer/Countdown/StopCountdownRequest.cs

@@ -2,7 +2,6 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using MessagePack;
-using Newtonsoft.Json;
 
 namespace osu.Game.Online.Multiplayer.Countdown
 {
@@ -12,14 +11,5 @@ namespace osu.Game.Online.Multiplayer.Countdown
     [MessagePackObject]
     public class StopCountdownRequest : MatchUserRequest
     {
-        [Key(0)]
-        public readonly int ID;
-
-        [JsonConstructor]
-        [SerializationConstructor]
-        public StopCountdownRequest(int id)
-        {
-            ID = id;
-        }
     }
 }

osu.Game/Online/Multiplayer/ForceGameplayStartCountdown.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Online.Multiplayer
     /// and forcing progression of any clients that are blocking load due to user interaction.
     /// </summary>
     [MessagePackObject]
-    public sealed class ForceGameplayStartCountdown : MultiplayerCountdown
+    public class ForceGameplayStartCountdown : MultiplayerCountdown
     {
     }
 }

osu.Game/Online/Multiplayer/MatchServerEvent.cs

@@ -13,8 +13,7 @@ namespace osu.Game.Online.Multiplayer
     [Serializable]
     [MessagePackObject]
     // IMPORTANT: Add rules to SignalRUnionWorkaroundResolver for new derived types.
-    [Union(0, typeof(CountdownStartedEvent))]
-    [Union(1, typeof(CountdownStoppedEvent))]
+    [Union(0, typeof(CountdownChangedEvent))]
     public abstract class MatchServerEvent
     {
     }

osu.Game/Online/Multiplayer/MatchStartCountdown.cs

@@ -9,7 +9,7 @@ namespace osu.Game.Online.Multiplayer
     /// A <see cref="MultiplayerCountdown"/> which will start the match after ending.
     /// </summary>
     [MessagePackObject]
-    public sealed class MatchStartCountdown : MultiplayerCountdown
+    public class MatchStartCountdown : MultiplayerCountdown
     {
     }
 }

osu.Game/Online/Multiplayer/MultiplayerClient.cs

@@ -552,14 +552,8 @@ namespace osu.Game.Online.Multiplayer
 
                 switch (e)
                 {
-                    case CountdownStartedEvent countdownStartedEvent:
-                        Room.ActiveCountdowns.Add(countdownStartedEvent.Countdown);
-                        break;
-
-                    case CountdownStoppedEvent countdownStoppedEvent:
-                        MultiplayerCountdown? countdown = Room.ActiveCountdowns.FirstOrDefault(countdown => countdown.ID == countdownStoppedEvent.ID);
-                        if (countdown != null)
-                            Room.ActiveCountdowns.Remove(countdown);
+                    case CountdownChangedEvent countdownChangedEvent:
+                        Room.Countdown = countdownChangedEvent.Countdown;
                         break;
                 }
 

osu.Game/Online/Multiplayer/MultiplayerCountdown.cs

@@ -15,24 +15,13 @@ namespace osu.Game.Online.Multiplayer
     [Union(1, typeof(ForceGameplayStartCountdown))]
     public abstract class MultiplayerCountdown
     {
-        /// <summary>
-        /// A unique identifier for this countdown.
-        /// </summary>
-        [Key(0)]
-        public int ID { get; set; }
-
         /// <summary>
         /// The amount of time remaining in the countdown.
         /// </summary>
         /// <remarks>
-        /// This is only sent once from the server upon initial retrieval of the <see cref="MultiplayerRoom"/> or via a <see cref="CountdownStartedEvent"/>.
+        /// This is only sent once from the server upon initial retrieval of the <see cref="MultiplayerRoom"/> or via a <see cref="CountdownChangedEvent"/>.
         /// </remarks>
-        [Key(1)]
+        [Key(0)]
         public TimeSpan TimeRemaining { get; set; }
-
-        /// <summary>
-        /// Whether only a single instance of this <see cref="MultiplayerCountdown"/> type may be active at any one time.
-        /// </summary>
-        public virtual bool IsExclusive => true;
     }
 }

osu.Game/Online/Multiplayer/MultiplayerRoom.cs

@@ -53,10 +53,10 @@ namespace osu.Game.Online.Multiplayer
         public IList<MultiplayerPlaylistItem> Playlist { get; set; } = new List<MultiplayerPlaylistItem>();
 
         /// <summary>
-        /// The currently running countdowns.
+        /// The currently-running countdown.
         /// </summary>
         [Key(7)]
-        public IList<MultiplayerCountdown> ActiveCountdowns { get; set; } = new List<MultiplayerCountdown>();
+        public MultiplayerCountdown? Countdown { get; set; }
 
         [JsonConstructor]
         [SerializationConstructor]

osu.Game/Online/SignalRWorkaroundTypes.cs

@@ -23,8 +23,7 @@ namespace osu.Game.Online
             (typeof(ChangeTeamRequest), typeof(MatchUserRequest)),
             (typeof(StartMatchCountdownRequest), typeof(MatchUserRequest)),
             (typeof(StopCountdownRequest), typeof(MatchUserRequest)),
-            (typeof(CountdownStartedEvent), typeof(MatchServerEvent)),
-            (typeof(CountdownStoppedEvent), typeof(MatchServerEvent)),
+            (typeof(CountdownChangedEvent), typeof(MatchServerEvent)),
             (typeof(TeamVersusRoomState), typeof(MatchRoomState)),
             (typeof(TeamVersusUserState), typeof(MatchUserState)),
             (typeof(MatchStartCountdown), typeof(MultiplayerCountdown)),

osu.Game/Screens/OnlinePlay/Multiplayer/Match/MatchStartControl.cs

@@ -109,7 +109,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
             Debug.Assert(clickOperation == null);
             clickOperation = ongoingOperationTracker.BeginOperation();
 
-            if (isReady() && Client.IsHost && !Room.ActiveCountdowns.Any(c => c is MatchStartCountdown))
+            if (isReady() && Client.IsHost && Room.Countdown == null)
                 startMatch();
             else
                 toggleReady();
@@ -140,14 +140,10 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
 
         private void cancelCountdown()
         {
-            if (Client.Room == null)
-                return;
-
             Debug.Assert(clickOperation == null);
             clickOperation = ongoingOperationTracker.BeginOperation();
 
-            MultiplayerCountdown countdown = Client.Room.ActiveCountdowns.Single(c => c is MatchStartCountdown);
-            Client.SendMatchRequest(new StopCountdownRequest(countdown.ID)).ContinueWith(_ => endOperation());
+            Client.SendMatchRequest(new StopCountdownRequest()).ContinueWith(_ => endOperation());
         }
 
         private void endOperation()
@@ -196,7 +192,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
 
             // When the local user is the host and spectating the match, the ready button should be enabled only if any users are ready.
             if (localUser?.State == MultiplayerUserState.Spectating)
-                readyButton.Enabled.Value &= Client.IsHost && newCountReady > 0 && !Room.ActiveCountdowns.Any(c => c is MatchStartCountdown);
+                readyButton.Enabled.Value &= Client.IsHost && newCountReady > 0 && Room.Countdown == null;
 
             if (newCountReady == countReady)
                 return;

osu.Game/Screens/OnlinePlay/Multiplayer/Match/MultiplayerCountdownButton.cs

@@ -4,7 +4,6 @@
 #nullable disable
 
 using System;
-using System.Linq;
 using Humanizer;
 using osu.Framework.Allocation;
 using osu.Framework.Extensions;
@@ -80,7 +79,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
 
         private void onRoomUpdated() => Scheduler.AddOnce(() =>
         {
-            bool countdownActive = multiplayerClient.Room?.ActiveCountdowns.Any(c => c is MatchStartCountdown) == true;
+            bool countdownActive = multiplayerClient.Room?.Countdown is MatchStartCountdown;
 
             if (countdownActive)
             {
@@ -122,7 +121,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
                 });
             }
 
-            if (multiplayerClient.Room?.ActiveCountdowns.Any(c => c is MatchStartCountdown) == true && multiplayerClient.IsHost)
+            if (multiplayerClient.Room?.Countdown != null && multiplayerClient.IsHost)
             {
                 flow.Add(new OsuButton
                 {

osu.Game/Screens/OnlinePlay/Multiplayer/Match/MultiplayerReadyButton.cs

@@ -57,11 +57,23 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
 
         private void onRoomUpdated() => Scheduler.AddOnce(() =>
         {
-            MultiplayerCountdown newCountdown = room?.ActiveCountdowns.SingleOrDefault(c => c is MatchStartCountdown);
+            MultiplayerCountdown newCountdown;
+
+            switch (room?.Countdown)
+            {
+                case MatchStartCountdown:
+                    newCountdown = room.Countdown;
+                    break;
+
+                // Clear the countdown with any other (including non-null) countdown values.
+                default:
+                    newCountdown = null;
+                    break;
+            }
 
             if (newCountdown != countdown)
             {
-                countdown = newCountdown;
+                countdown = room?.Countdown;
                 countdownChangeTime = Time.Current;
             }
 
@@ -201,7 +213,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
 
                 case MultiplayerUserState.Spectating:
                 case MultiplayerUserState.Ready:
-                    if (room?.Host?.Equals(localUser) == true && !room.ActiveCountdowns.Any(c => c is MatchStartCountdown))
+                    if (room?.Host?.Equals(localUser) == true && room.Countdown == null)
                         setGreen();
                     else
                         setYellow();
@@ -236,13 +248,8 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
         {
             get
             {
-                if (room?.ActiveCountdowns.Any(c => c is MatchStartCountdown) == true
-                    && multiplayerClient.IsHost
-                    && multiplayerClient.LocalUser?.State == MultiplayerUserState.Ready
-                    && !room.Settings.AutoStartEnabled)
-                {
+                if (room?.Countdown != null && multiplayerClient.IsHost && multiplayerClient.LocalUser?.State == MultiplayerUserState.Ready && !room.Settings.AutoStartEnabled)
                     return "Cancel countdown";
-                }
 
                 return base.TooltipText;
             }