From b2ce3421e50dc6082d207febc703a60c7798d976 Mon Sep 17 00:00:00 2001
From: Justin Nolan <justin@nolan.de>
Date: Thu, 11 Nov 2021 14:47:33 +0800
Subject: [PATCH] fix: networkmanager undo and move some validation into
 Reset() (#2990)

* Fix network manager undo and move some validation code into Reset()

* Add comments
---
 Assets/Mirror/Runtime/NetworkManager.cs | 70 ++++++++++++++-----------
 1 file changed, 39 insertions(+), 31 deletions(-)

diff --git a/Assets/Mirror/Runtime/NetworkManager.cs b/Assets/Mirror/Runtime/NetworkManager.cs
index a76604bba..18ac046cc 100644
--- a/Assets/Mirror/Runtime/NetworkManager.cs
+++ b/Assets/Mirror/Runtime/NetworkManager.cs
@@ -133,37 +133,6 @@ public class NetworkManager : MonoBehaviour
         // virtual so that inheriting classes' OnValidate() can call base.OnValidate() too
         public virtual void OnValidate()
         {
-            // make sure someone doesn't accidentally add another NetworkManager
-            // need transform.root because when adding to a child, the parent's
-            // OnValidate isn't called.
-            foreach (NetworkManager manager in transform.root.GetComponentsInChildren<NetworkManager>())
-            {
-                if (manager != this)
-                {
-                    Debug.LogError($"{name} detected another component of type {typeof(NetworkManager)} in its hierarchy on {manager.name}. There can only be one, please remove one of them.");
-                    // return early so that transport component isn't auto-added
-                    // to the duplicate NetworkManager.
-                    return;
-                }
-            }
-
-            // add transport if there is none yet. makes upgrading easier.
-            if (transport == null)
-            {
-                // was a transport added yet? if not, add one
-                transport = GetComponent<Transport>();
-                if (transport == null)
-                {
-                    transport = gameObject.AddComponent<KcpTransport>();
-                    Debug.Log("NetworkManager: added default Transport because there was none yet.");
-                }
-#if UNITY_EDITOR
-                // For some insane reason, this line fails when building unless wrapped in this define. Stupid but true.
-                // error CS0234: The type or namespace name 'Undo' does not exist in the namespace 'UnityEditor' (are you missing an assembly reference?)
-                UnityEditor.Undo.RecordObject(gameObject, "Added default Transport");
-#endif
-            }
-
             // always >= 0
             maxConnections = Mathf.Max(maxConnections, 0);
 
@@ -181,6 +150,45 @@ public virtual void OnValidate()
             }
         }
 
+        // virtual so that inheriting classes' Reset() can call base.Reset() too
+        // Reset only gets called when the component is added or the user resets the component
+        // Thats why we validate these things that only need to be validated on adding the NetworkManager here
+        // If we would do it in OnValidate() then it would run this everytime a value changes
+        public virtual void Reset()
+        {
+            // make sure someone doesn't accidentally add another NetworkManager
+            // need transform.root because when adding to a child, the parent's
+            // Reset isn't called.
+            foreach (NetworkManager manager in transform.root.GetComponentsInChildren<NetworkManager>())
+            {
+                if (manager != this)
+                {
+                    Debug.LogError($"{name} detected another component of type {typeof(NetworkManager)} in its hierarchy on {manager.name}. There can only be one, please remove one of them.");
+                    // return early so that transport component isn't auto-added
+                    // to the duplicate NetworkManager.
+                    return;
+                }
+            }
+
+            // add transport if there is none yet. makes upgrading easier.
+            if (transport == null)
+            {
+#if UNITY_EDITOR
+                // RecordObject needs to be called before we make the change
+                UnityEditor.Undo.RecordObject(gameObject, "Added default Transport");
+#endif
+                
+                transport = GetComponent<Transport>();
+
+                // was a transport added yet? if not, add one
+                if (transport == null)
+                {
+                    transport = gameObject.AddComponent<KcpTransport>();
+                    Debug.Log("NetworkManager: added default Transport because there was none yet.");
+                }
+            }
+        }
+
         // virtual so that inheriting classes' Awake() can call base.Awake() too
         public virtual void Awake()
         {