fix: Revert "refactor: consolidate prefab and spawn handlers (#817)" …

…to fix a bug where if editor=host, build=client, we receive scene object not found when walking out of and back into an observer's range

This reverts commit b4c9c6f.

Assets/Mirror/Runtime/ClientScene.cs

@@ -18,7 +18,6 @@ public static class ClientScene
         public static bool ready { get; internal set; }
         public static NetworkConnection readyConnection { get; private set; }
 
-        [Obsolete]
         public static Dictionary<Guid, GameObject> prefabs = new Dictionary<Guid, GameObject>();
         // scene id to NetworkIdentity
         public static Dictionary<ulong, NetworkIdentity> spawnableObjects;
@@ -176,20 +175,38 @@ static NetworkIdentity SpawnSceneObject(ulong sceneId)
             return null;
         }
 
+        // spawn handlers and prefabs
+        static bool GetPrefab(Guid assetId, out GameObject prefab)
+        {
+            prefab = null;
+            return assetId != Guid.Empty &&
+                   prefabs.TryGetValue(assetId, out prefab) && prefab != null;
+        }
+
         // this assigns the newAssetId to the prefab. This is for registering dynamically created game objects for already know assetIds.
         public static void RegisterPrefab(GameObject prefab, Guid newAssetId)
         {
-            RegisterSpawnHandler(newAssetId, 
-                (position, assetId) => Object.Instantiate(prefab),
-                (spawned) => Object.Destroy(spawned));
+            NetworkIdentity identity = prefab.GetComponent<NetworkIdentity>();
+            if (identity)
+            {
+                identity.assetId = newAssetId;
+
+                if (LogFilter.Debug) Debug.Log("Registering prefab '" + prefab.name + "' as asset:" + identity.assetId);
+                prefabs[identity.assetId] = prefab;
+            }
+            else
+            {
+                Debug.LogError("Could not register '" + prefab.name + "' since it contains no NetworkIdentity component");
+            }
         }
 
         public static void RegisterPrefab(GameObject prefab)
         {
             NetworkIdentity identity = prefab.GetComponent<NetworkIdentity>();
             if (identity)
             {
-                RegisterPrefab(prefab, identity.assetId);
+                if (LogFilter.Debug) Debug.Log("Registering prefab '" + prefab.name + "' as asset:" + identity.assetId);
+                prefabs[identity.assetId] = prefab;
 
                 NetworkIdentity[] identities = prefab.GetComponentsInChildren<NetworkIdentity>();
                 if (identities.Length > 1)
@@ -219,7 +236,16 @@ public static void RegisterPrefab(GameObject prefab, SpawnDelegate spawnHandler,
                 return;
             }
 
-            RegisterSpawnHandler(identity.assetId, spawnHandler, unspawnHandler);
+            if (identity.assetId == Guid.Empty)
+            {
+                Debug.LogError("RegisterPrefab game object " + prefab.name + " has no prefab. Use RegisterSpawnHandler() instead?");
+                return;
+            }
+
+            if (LogFilter.Debug) Debug.Log("Registering custom prefab '" + prefab.name + "' as asset:" + identity.assetId + " " + spawnHandler.GetMethodName() + "/" + unspawnHandler.GetMethodName());
+
+            spawnHandlers[identity.assetId] = spawnHandler;
+            unspawnHandlers[identity.assetId] = unspawnHandler;
         }
 
         public static void UnregisterPrefab(GameObject prefab)
@@ -230,7 +256,8 @@ public static void UnregisterPrefab(GameObject prefab)
                 Debug.LogError("Could not unregister '" + prefab.name + "' since it contains no NetworkIdentity component");
                 return;
             }
-            UnregisterSpawnHandler(identity.assetId);
+            spawnHandlers.Remove(identity.assetId);
+            unspawnHandlers.Remove(identity.assetId);
         }
 
         public static void RegisterSpawnHandler(Guid assetId, SpawnDelegate spawnHandler, UnSpawnDelegate unspawnHandler)
@@ -241,11 +268,6 @@ public static void RegisterSpawnHandler(Guid assetId, SpawnDelegate spawnHandler
                 return;
             }
 
-            if (assetId == Guid.Empty)
-            { 
-                Debug.LogError($"Registering invalid asset id {assetId}");
-                return;
-            }
             if (LogFilter.Debug) Debug.Log("RegisterSpawnHandler asset '" + assetId + "' " + spawnHandler.GetMethodName() + "/" + unspawnHandler.GetMethodName());
 
             spawnHandlers[assetId] = spawnHandler;
@@ -260,6 +282,7 @@ public static void UnregisterSpawnHandler(Guid assetId)
 
         public static void ClearSpawners()
         {
+            prefabs.Clear();
             spawnHandlers.Clear();
             unspawnHandlers.Clear();
         }
@@ -357,7 +380,25 @@ internal static void OnSpawnPrefab(NetworkConnection conn, SpawnPrefabMessage ms
                 return;
             }
 
-            if (spawnHandlers.TryGetValue(msg.assetId, out SpawnDelegate handler))
+            if (GetPrefab(msg.assetId, out GameObject prefab))
+            {
+                GameObject obj = Object.Instantiate(prefab, msg.position, msg.rotation);
+                if (LogFilter.Debug)
+                {
+                    Debug.Log("Client spawn handler instantiating [netId:" + msg.netId + " asset ID:" + msg.assetId + " pos:" + msg.position + " rotation: " + msg.rotation + "]");
+                }
+
+                localObject = obj.GetComponent<NetworkIdentity>();
+                if (localObject == null)
+                {
+                    Debug.LogError("Client object spawned for " + msg.assetId + " does not have a NetworkIdentity");
+                    return;
+                }
+                localObject.Reset();
+                ApplySpawnPayload(localObject, msg.position, msg.rotation, msg.scale, msg.payload, msg.netId);
+            }
+            // lookup registered factory for type:
+            else if (spawnHandlers.TryGetValue(msg.assetId, out SpawnDelegate handler))
             {
                 GameObject obj = handler(msg.position, msg.assetId);
                 if (obj == null)