From 0ea982c036814109f43851716d3fc9124cdfb3ca Mon Sep 17 00:00:00 2001
From: smoogipoo <smoogipoo@smgi.me>
Date: Thu, 5 Aug 2021 22:49:41 +0900
Subject: [PATCH] Update recent participants list to use participant_count

---
 .../TestSceneRecentParticipantsList.cs        | 42 ++++++++++---------
 .../Components/RecentParticipantsList.cs      | 16 +++----
 2 files changed, 31 insertions(+), 27 deletions(-)

diff --git a/osu.Game.Tests/Visual/Multiplayer/TestSceneRecentParticipantsList.cs b/osu.Game.Tests/Visual/Multiplayer/TestSceneRecentParticipantsList.cs
index c9959b3467..f05c092dfb 100644
--- a/osu.Game.Tests/Visual/Multiplayer/TestSceneRecentParticipantsList.cs
+++ b/osu.Game.Tests/Visual/Multiplayer/TestSceneRecentParticipantsList.cs
@@ -36,13 +36,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("add 50 users", () =>
             {
                 for (int i = 0; i < 50; i++)
-                {
-                    SelectedRoom.Value.RecentParticipants.Add(new User
-                    {
-                        Id = i,
-                        Username = $"User {i}"
-                    });
-                }
+                    addUser(i);
             });
 
             AddStep("set 3 avatars", () => list.NumberOfAvatars = 3);
@@ -60,34 +54,44 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("add 50 users", () =>
             {
                 for (int i = 0; i < 50; i++)
-                {
-                    SelectedRoom.Value.RecentParticipants.Add(new User
-                    {
-                        Id = i,
-                        Username = $"User {i}"
-                    });
-                }
+                    addUser(i);
             });
 
-            AddStep("remove from start", () => SelectedRoom.Value.RecentParticipants.RemoveAt(0));
+            AddStep("remove from start", () => removeUserAt(0));
             AddAssert("3 avatars displayed", () => list.ChildrenOfType<UpdateableAvatar>().Count() == 3);
             AddAssert("46 hidden users", () => list.ChildrenOfType<RecentParticipantsList.HiddenUserCount>().Single().Count == 46);
 
-            AddStep("remove from end", () => SelectedRoom.Value.RecentParticipants.RemoveAt(SelectedRoom.Value.RecentParticipants.Count - 1));
+            AddStep("remove from end", () => removeUserAt(SelectedRoom.Value.RecentParticipants.Count - 1));
             AddAssert("3 avatars displayed", () => list.ChildrenOfType<UpdateableAvatar>().Count() == 3);
             AddAssert("45 hidden users", () => list.ChildrenOfType<RecentParticipantsList.HiddenUserCount>().Single().Count == 45);
 
-            AddRepeatStep("remove 45 users", () => SelectedRoom.Value.RecentParticipants.RemoveAt(0), 45);
+            AddRepeatStep("remove 45 users", () => removeUserAt(0), 45);
             AddAssert("3 avatars displayed", () => list.ChildrenOfType<UpdateableAvatar>().Count() == 3);
             AddAssert("0 hidden users", () => list.ChildrenOfType<RecentParticipantsList.HiddenUserCount>().Single().Count == 0);
             AddAssert("hidden users bubble hidden", () => list.ChildrenOfType<RecentParticipantsList.HiddenUserCount>().Single().Alpha < 0.5f);
 
-            AddStep("remove another user", () => SelectedRoom.Value.RecentParticipants.RemoveAt(0));
+            AddStep("remove another user", () => removeUserAt(0));
             AddAssert("2 avatars displayed", () => list.ChildrenOfType<UpdateableAvatar>().Count() == 2);
             AddAssert("0 hidden users", () => list.ChildrenOfType<RecentParticipantsList.HiddenUserCount>().Single().Count == 0);
 
-            AddRepeatStep("remove the remaining two users", () => SelectedRoom.Value.RecentParticipants.RemoveAt(0), 2);
+            AddRepeatStep("remove the remaining two users", () => removeUserAt(0), 2);
             AddAssert("0 avatars displayed", () => !list.ChildrenOfType<UpdateableAvatar>().Any());
         }
+
+        private void addUser(int id)
+        {
+            SelectedRoom.Value.ParticipantCount.Value++;
+            SelectedRoom.Value.RecentParticipants.Add(new User
+            {
+                Id = id,
+                Username = $"User {id}"
+            });
+        }
+
+        private void removeUserAt(int index)
+        {
+            SelectedRoom.Value.ParticipantCount.Value--;
+            SelectedRoom.Value.RecentParticipants.RemoveAt(index);
+        }
     }
 }
diff --git a/osu.Game/Screens/OnlinePlay/Lounge/Components/RecentParticipantsList.cs b/osu.Game/Screens/OnlinePlay/Lounge/Components/RecentParticipantsList.cs
index bbea1ea1c3..da410716e4 100644
--- a/osu.Game/Screens/OnlinePlay/Lounge/Components/RecentParticipantsList.cs
+++ b/osu.Game/Screens/OnlinePlay/Lounge/Components/RecentParticipantsList.cs
@@ -88,6 +88,7 @@ namespace osu.Game.Screens.OnlinePlay.Lounge.Components
             base.LoadComplete();
 
             RecentParticipants.BindCollectionChanged(onParticipantsChanged, true);
+            ParticipantCount.BindValueChanged(_ => updateHiddenUserCount(), true);
         }
 
         private int numberOfAvatars = 3;
@@ -141,8 +142,8 @@ namespace osu.Game.Screens.OnlinePlay.Lounge.Components
         {
             if (avatarFlow.Count < NumberOfAvatars)
                 avatarFlow.Add(new CircularAvatar { User = user });
-            else
-                hiddenUsers.Count++;
+
+            updateHiddenUserCount();
         }
 
         private void removeUser(User user)
@@ -150,21 +151,20 @@ namespace osu.Game.Screens.OnlinePlay.Lounge.Components
             if (avatarFlow.RemoveAll(a => a.User == user) > 0)
             {
                 if (RecentParticipants.Count >= NumberOfAvatars)
-                {
                     avatarFlow.Add(new CircularAvatar { User = RecentParticipants.First(u => avatarFlow.All(a => a.User != u)) });
-                    hiddenUsers.Count--;
-                }
             }
-            else
-                hiddenUsers.Count--;
+
+            updateHiddenUserCount();
         }
 
         private void clearUsers()
         {
             avatarFlow.Clear();
-            hiddenUsers.Count = 0;
+            updateHiddenUserCount();
         }
 
+        private void updateHiddenUserCount() => hiddenUsers.Count = ParticipantCount.Value - avatarFlow.Count;
+
         private class CircularAvatar : CompositeDrawable
         {
             public User User