Fix issue with FSM templates on entities that activate late

HKMP/Game/Client/Entity/Entity.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
@@ -275,6 +276,7 @@ private void ProcessHostFsm(PlayMakerFSM fsm) {
 
         for (var i = 0; i < fsm.FsmStates.Length; i++) {
             var state = fsm.FsmStates[i];
+            var stateName = state.Name;
 
             for (var j = 0; j < state.Actions.Length; j++) {
                 var action = state.Actions[j];
@@ -286,18 +288,56 @@ private void ProcessHostFsm(PlayMakerFSM fsm) {
                     continue;
                 }
 
-                _hookedActions[action] = new HookedEntityAction {
-                    Action = action,
-                    FsmIndex = _fsms.Host.IndexOf(fsm),
-                    StateIndex = i,
-                    ActionIndex = j
-                };
-                // Logger.Info($"Created hooked action: {action.GetType()}, {_fsms.Host.IndexOf(fsm)}, {state.Name}, {j}");
-
-                if (!_hookedTypes.Contains(action.GetType())) {
-                    _hookedTypes.Add(action.GetType());
+                Func<FsmStateAction> actionFunc;
+                var stateIndex = i;
+                var actionIndex = j;
+
+                // Because it can happen that the action from a state is not properly initialized (usually when the
+                // entity is made active later in the scene and uses an FSM template), we need to check it here
+                // and create a coroutine that waits for FSM to properly initialize all its states and only then
+                // continue. When continuing, we no longer use the same instance of the action and state, so we
+                // use a function that re-obtains the correct action to make a hook from
+                // This is all complicated logic simply because it happens (empirically) once for the Grimm boss fight
+                if (action.Fsm == null) {
+                    actionFunc = () => fsm.FsmStates[stateIndex].Actions[actionIndex];
+                    var checkFunc = () => actionFunc.Invoke().Fsm == null;
+                    var sceneName = fsm.gameObject.scene.name;
+
+                    Logger.Debug($"Registering delayed hook for action that is not valid: {action.GetType()}, {_fsms.Host.IndexOf(fsm)}, {stateName}, {actionIndex}");
+
+                    MonoBehaviourUtil.Instance.StartCoroutine(WaitForActionInitialization());
+                    IEnumerator WaitForActionInitialization() {
+                        while (checkFunc.Invoke()) {
+                            if (UnityEngine.SceneManagement.SceneManager.GetActiveScene().name != sceneName) {
+                                yield break;
+                            }
+
+                            yield return new WaitForSeconds(0.1f);
+                        }
+
+                        Logger.Debug("Delayed hook action is now valid, continuing...");
+                        CreateHookedAction();
+                    }
+                } else {
+                    actionFunc = () => action;
+                    CreateHookedAction();
+                }
 
-                    FsmActionHooks.RegisterFsmStateActionType(action.GetType(), OnActionEntered);
+                void CreateHookedAction() {
+                    var hookedAction = actionFunc.Invoke();
+
+                    _hookedActions[hookedAction] = new HookedEntityAction {
+                        Action = hookedAction,
+                        FsmIndex = _fsms.Host.IndexOf(fsm),
+                        StateIndex = stateIndex,
+                        ActionIndex = actionIndex
+                    };
+                    Logger.Info(
+                        $"Created hooked action: {hookedAction.GetType()}, {_fsms.Host.IndexOf(fsm)}, {stateName}, {actionIndex}");
+
+                    if (_hookedTypes.Add(hookedAction.GetType())) {
+                        FsmActionHooks.RegisterFsmStateActionType(hookedAction.GetType(), OnActionEntered);
+                    }
                 }
             }
         }

HKMP/Game/Client/Entity/EntityInitializer.cs

@@ -78,9 +78,14 @@ public static void InitializeFsm(PlayMakerFSM fsm) {
         // Now we can loop over the states in the same order as our "InitStateNames" array
         foreach (var state in statesToInit) {
             Logger.Debug($"Found initialization state: {state.Name}, executing actions");
+
+            // The index of the state in the FSM, NOT in the list of states to initialize
+            var stateIndex = Array.IndexOf(fsm.FsmStates, state);
 
             // Go over each action and try to execute it by applying empty data to it
-            foreach (var action in state.Actions) {
+            for (var actionIndex = 0; actionIndex < state.Actions.Length; actionIndex++) {
+                var action = state.Actions[actionIndex];
+
                 if (!action.Enabled) {
                     continue;
                 }
@@ -93,15 +98,24 @@ public static void InitializeFsm(PlayMakerFSM fsm) {
                     if (action.Fsm == null) {
                         Logger.Debug("Initializing FSM and action.Fsm is null, starting coroutine");
 
+                        var finalActionIndex = actionIndex;
+                        var sceneName = fsm.gameObject.scene.name;
+                        var actionFunc = () => fsm.FsmStates[stateIndex].Actions[finalActionIndex];
+                        var checkFunc = () => actionFunc.Invoke().Fsm == null;
+
                         MonoBehaviourUtil.Instance.StartCoroutine(WaitForActionInitialization());
                         IEnumerator WaitForActionInitialization() {
-                            while (action.Fsm == null) {
+                            while (checkFunc.Invoke()) {
+                                if (UnityEngine.SceneManagement.SceneManager.GetActiveScene().name != sceneName) {
+                                    yield break;
+                                }
+
                                 yield return new WaitForSeconds(0.1f);
                             }
 
-                            Logger.Debug("Initializing FSM action completed");
+                            Logger.Debug($"Initializing FSM action completed, executing action: {actionFunc.Invoke().GetType()}");
 
-                            EntityFsmActions.ApplyNetworkDataFromAction(null, action);                            
+                            EntityFsmActions.ApplyNetworkDataFromAction(null, actionFunc.Invoke());                            
                         }
 
                         continue;