From 84953d93f79e82eb6ed6a73010ab87b7d4b6ff54 Mon Sep 17 00:00:00 2001
From: Riryan <anthonyfmitchell@gmail.com>
Date: Tue, 26 May 2026 18:17:32 -0500
Subject: [PATCH] Refactor UpdateManager instance handling and registration

---
 .../UpdateManager/Scripts/UpdateManager.cs    | 108 +++++++++++++++---
 1 file changed, 92 insertions(+), 16 deletions(-)

diff --git a/ThirdParty/UpdateManager/Scripts/UpdateManager.cs b/ThirdParty/UpdateManager/Scripts/UpdateManager.cs
index 44de24ec9..f73edb98b 100644
--- a/ThirdParty/UpdateManager/Scripts/UpdateManager.cs
+++ b/ThirdParty/UpdateManager/Scripts/UpdateManager.cs
@@ -9,7 +9,21 @@ public sealed class UpdateManager : MonoBehaviour
         private static readonly SortedList<int, Updater> _updaters = new SortedList<int, Updater>();
 
         private static UpdateManager _instance;
-        public static UpdateManager Instance => _instance != null ? _instance : (_instance = CreateInstance());
+        private static bool _applicationIsQuitting;
+
+        public static UpdateManager Instance => GetOrCreateInstance();
+
+        private static UpdateManager GetOrCreateInstance()
+        {
+            if (_applicationIsQuitting)
+                return null;
+
+            if (_instance != null)
+                return _instance;
+
+            _instance = FindObjectOfType<UpdateManager>();
+            return _instance != null ? _instance : CreateInstance();
+        }
 
         private static UpdateManager CreateInstance()
         {
@@ -17,6 +31,7 @@ private static UpdateManager CreateInstance()
             {
                 hideFlags = HideFlags.DontSave,
             };
+
 #if UNITY_EDITOR
             if (!Application.isPlaying)
             {
@@ -27,12 +42,46 @@ private static UpdateManager CreateInstance()
             {
                 DontDestroyOnLoad(gameObject);
             }
+
             return gameObject.AddComponent<UpdateManager>();
         }
 
+        private void Awake()
+        {
+            if (_instance != null && _instance != this)
+            {
+                Destroy(gameObject);
+                return;
+            }
+
+            _instance = this;
+        }
+
+        private void OnApplicationQuit()
+        {
+            _applicationIsQuitting = true;
+        }
+
+        private void OnDestroy()
+        {
+            if (_instance != this)
+                return;
+
+            _instance = null;
+            _defaultUpdater.Clear();
+            _updaters.Clear();
+        }
+
         public static void Register(IManagedUpdateBase updater)
         {
-            Instance.Register_Implementation(updater);
+            if (updater == null)
+                return;
+
+            UpdateManager instance = GetOrCreateInstance();
+            if (instance == null)
+                return;
+
+            instance.Register_Implementation(updater);
         }
 
         private void Register_Implementation(IManagedUpdateBase updater)
@@ -42,7 +91,10 @@ private void Register_Implementation(IManagedUpdateBase updater)
 
         public static void Unregister(IManagedUpdateBase updater)
         {
-            Instance.Unregister_Implementation(updater);
+            if (updater == null || _instance == null)
+                return;
+
+            _instance.Unregister_Implementation(updater);
         }
 
         private void Unregister_Implementation(IManagedUpdateBase updater)
@@ -52,52 +104,76 @@ private void Unregister_Implementation(IManagedUpdateBase updater)
 
         public static void Register(int order, IManagedUpdateBase updater)
         {
-            Instance.Register_Implementation(order, updater);
+            if (updater == null)
+                return;
+
+            UpdateManager instance = GetOrCreateInstance();
+            if (instance == null)
+                return;
+
+            instance.Register_Implementation(order, updater);
         }
 
         private void Register_Implementation(int order, IManagedUpdateBase updater)
         {
-            if (!_updaters.ContainsKey(order))
-                _updaters.Add(order, new Updater());
-            _updaters[order].Register(updater);
+            if (!_updaters.TryGetValue(order, out Updater updaterGroup))
+            {
+                updaterGroup = new Updater();
+                _updaters.Add(order, updaterGroup);
+            }
+
+            updaterGroup.Register(updater);
         }
 
         public static void Unregister(int order, IManagedUpdateBase updater)
         {
-            Instance.Unregister_Implementation(order, updater);
+            if (updater == null || _instance == null)
+                return;
+
+            _instance.Unregister_Implementation(order, updater);
         }
 
         private void Unregister_Implementation(int order, IManagedUpdateBase updater)
         {
-            if (!_updaters.ContainsKey(order))
+            if (!_updaters.TryGetValue(order, out Updater updaterGroup))
                 return;
-            _updaters[order].Unregister(updater);
+
+            updaterGroup.Unregister(updater);
+
+            if (updaterGroup.IsEmpty)
+                _updaters.Remove(order);
         }
 
         private void Update()
         {
             _defaultUpdater.Update();
-            for (int i = 0; i < _updaters.Count; ++i)
+
+            IList<Updater> orderedUpdaters = _updaters.Values;
+            for (int i = 0, count = orderedUpdaters.Count; i < count; ++i)
             {
-                _updaters.Values[i].Update();
+                orderedUpdaters[i].Update();
             }
         }
 
         private void LateUpdate()
         {
             _defaultUpdater.LateUpdate();
-            for (int i = 0; i < _updaters.Count; ++i)
+
+            IList<Updater> orderedUpdaters = _updaters.Values;
+            for (int i = 0, count = orderedUpdaters.Count; i < count; ++i)
             {
-                _updaters.Values[i].LateUpdate();
+                orderedUpdaters[i].LateUpdate();
             }
         }
 
         private void FixedUpdate()
         {
             _defaultUpdater.FixedUpdate();
-            for (int i = 0; i < _updaters.Count; ++i)
+
+            IList<Updater> orderedUpdaters = _updaters.Values;
+            for (int i = 0, count = orderedUpdaters.Count; i < count; ++i)
             {
-                _updaters.Values[i].FixedUpdate();
+                orderedUpdaters[i].FixedUpdate();
             }
         }
     }