Add Scripted state and bAutoStartBehavior for external NPC control

Allow NPCs to start without a Behavior Tree and be controlled externally
via Blueprint, Level Sequences, or triggers. Adds Scripted enum state that
prevents BT services from overriding state, plus StartBehavior/StopBehavior
BlueprintCallable functions to toggle BT execution at runtime.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Unreal/PS_AI_Agent/Plugins/PS_AI_Behavior/Source/PS_AI_Behavior/Private/BT/PS_AI_Behavior_BTService_EvaluateReaction.cpp

@@ -25,6 +25,9 @@ void UPS_AI_Behavior_BTService_EvaluateReaction::TickNode(
 	APS_AI_Behavior_AIController* AIC = Cast<APS_AI_Behavior_AIController>(OwnerComp.GetAIOwner());
 	if (!AIC) { UE_LOG(LogPS_AI_Behavior, Warning, TEXT("EvaluateReaction: no AIC!")); return; }
 
+	// Scripted state: external control — don't touch the state
+	if (AIC->GetBehaviorState() == EPS_AI_Behavior_State::Scripted) { return; }
+
 	UPS_AI_Behavior_PersonalityComponent* Personality = AIC->GetPersonalityComponent();
 	if (!Personality) { UE_LOG(LogPS_AI_Behavior, Warning, TEXT("[%s] EvaluateReaction: no PersonalityComponent!"), *AIC->GetName()); return; }
 

Unreal/PS_AI_Agent/Plugins/PS_AI_Behavior/Source/PS_AI_Behavior/Private/BT/PS_AI_Behavior_BTService_UpdateThreat.cpp

@@ -25,6 +25,9 @@ void UPS_AI_Behavior_BTService_UpdateThreat::TickNode(
 	APS_AI_Behavior_AIController* AIC = Cast<APS_AI_Behavior_AIController>(OwnerComp.GetAIOwner());
 	if (!AIC) return;
 
+	// Scripted state: external control — don't accumulate threat
+	if (AIC->GetBehaviorState() == EPS_AI_Behavior_State::Scripted) { return; }
+
 	UBlackboardComponent* BB = OwnerComp.GetBlackboardComponent();
 	if (!BB) return;
 

Unreal/PS_AI_Agent/Plugins/PS_AI_Behavior/Source/PS_AI_Behavior/Private/PS_AI_Behavior_AIController.cpp

@@ -80,12 +80,24 @@ void APS_AI_Behavior_AIController::OnPossess(APawn* InPawn)
 	}
 
 	SetupBlackboard();
-	StartBehavior();
+
+	if (bAutoStartBehavior)
+	{
+		StartBehavior();
+	}
+	else
+	{
+		// Stay in Scripted state — no BT, no services, controlled externally
+		SetBehaviorState(EPS_AI_Behavior_State::Scripted);
+		UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s] bAutoStartBehavior=false — entering Scripted state."),
+			*GetName());
+	}
+
 	TryBindConversationAgent();
 	TryBindGazeComponent();
 
-	UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s] Possessed Pawn '%s' — BT started, TeamId=%d."),
+	UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s] Possessed Pawn '%s' — TeamId=%d, AutoStart=%d."),
-		*GetName(), *InPawn->GetName(), TeamId);
+		*GetName(), *InPawn->GetName(), TeamId, (int32)bAutoStartBehavior);
 }
 
 void APS_AI_Behavior_AIController::OnUnPossess()
@@ -227,24 +239,84 @@ void APS_AI_Behavior_AIController::SetupBlackboard()
 
 void APS_AI_Behavior_AIController::StartBehavior()
 {
+	UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s] StartBehavior called. Pawn=%s, HasBB=%d"),
+		*GetName(),
+		GetPawn() ? *GetPawn()->GetName() : TEXT("null"),
+		Blackboard != nullptr);
+
+	// Check if a BT was previously loaded and stopped (StopBehavior case)
+	UBehaviorTreeComponent* BTComp = Cast<UBehaviorTreeComponent>(GetBrainComponent());
+	UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s]   BrainComponent=%s, BTComp=%s, CurrentTree=%s, IsRunning=%d"),
+		*GetName(),
+		GetBrainComponent() ? *GetBrainComponent()->GetName() : TEXT("null"),
+		BTComp ? *BTComp->GetName() : TEXT("null"),
+		(BTComp && BTComp->GetCurrentTree()) ? *BTComp->GetCurrentTree()->GetName() : TEXT("null"),
+		BTComp ? (int32)BTComp->IsRunning() : -1);
+
+	if (BTComp && BTComp->GetCurrentTree() && !BTComp->IsRunning())
+	{
+		BTComp->RestartLogic();
+
+		if (GetBehaviorState() == EPS_AI_Behavior_State::Scripted)
+		{
+			SetBehaviorState(EPS_AI_Behavior_State::Idle);
+		}
+
+		UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s] StartBehavior — BT restarted (RestartLogic). IsRunning=%d"),
+			*GetName(), (int32)BTComp->IsRunning());
+		return;
+	}
+
+	// First-time start: load and run the BT
 	UBehaviorTree* BTToRun = BehaviorTreeAsset;
+	UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s]   BehaviorTreeAsset=%s"),
+		*GetName(), BTToRun ? *BTToRun->GetName() : TEXT("null"));
 
 	// Fallback: get from personality profile
 	if (!BTToRun && PersonalityComp && PersonalityComp->Profile)
 	{
 		BTToRun = PersonalityComp->Profile->DefaultBehaviorTree.LoadSynchronous();
+		UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s]   Loaded from Profile: %s"),
+			*GetName(), BTToRun ? *BTToRun->GetName() : TEXT("null"));
 	}
 
-	if (BTToRun)
+	if (!BTToRun)
-	{
-		RunBehaviorTree(BTToRun);
-	}
-	else
 	{
 		UE_LOG(LogPS_AI_Behavior, Warning,
-			TEXT("[%s] No BehaviorTree assigned and none in PersonalityProfile — NPC will be inert."),
+			TEXT("[%s] StartBehavior FAILED — No BehaviorTree assigned and none in PersonalityProfile."),
 			*GetName());
+		return;
 	}
+
+	const bool bSuccess = RunBehaviorTree(BTToRun);
+	UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s] RunBehaviorTree('%s') returned %d"),
+		*GetName(), *BTToRun->GetName(), (int32)bSuccess);
+
+	// Check post-run state
+	BTComp = Cast<UBehaviorTreeComponent>(GetBrainComponent());
+	UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s]   Post-run: BTComp=%s, IsRunning=%d, BB=%s"),
+		*GetName(),
+		BTComp ? *BTComp->GetName() : TEXT("null"),
+		BTComp ? (int32)BTComp->IsRunning() : -1,
+		Blackboard ? TEXT("valid") : TEXT("null"));
+
+	if (bSuccess && GetBehaviorState() == EPS_AI_Behavior_State::Scripted)
+	{
+		SetBehaviorState(EPS_AI_Behavior_State::Idle);
+	}
+}
+
+void APS_AI_Behavior_AIController::StopBehavior()
+{
+	if (UBrainComponent* Brain = GetBrainComponent())
+	{
+		Brain->StopLogic(TEXT("Scripted"));
+	}
+
+	StopMovement();
+	SetBehaviorState(EPS_AI_Behavior_State::Scripted);
+
+	UE_LOG(LogPS_AI_Behavior, Log, TEXT("[%s] StopBehavior — BT stopped, entering Scripted state."), *GetName());
 }
 
 void APS_AI_Behavior_AIController::SetBehaviorState(EPS_AI_Behavior_State NewState)
@@ -274,6 +346,12 @@ void APS_AI_Behavior_AIController::SetBehaviorState(EPS_AI_Behavior_State NewSta
 			}
 		}
 
+		// ─── Scripted: stop movement, NPC stays alive ──────────────
+		if (NewState == EPS_AI_Behavior_State::Scripted)
+		{
+			StopMovement();
+		}
+
 		// ─── Dead: shut down all AI systems ─────────────────────────
 		if (NewState == EPS_AI_Behavior_State::Dead)
 		{

Unreal/PS_AI_Agent/Plugins/PS_AI_Behavior/Source/PS_AI_Behavior/Private/PS_AI_Behavior_PersonalityComponent.cpp

@@ -72,6 +72,11 @@ EPS_AI_Behavior_State UPS_AI_Behavior_PersonalityComponent::EvaluateReaction() c
 		return EPS_AI_Behavior_State::Dead;
 	}
 
+	if (CurrentState == EPS_AI_Behavior_State::Scripted)
+	{
+		return EPS_AI_Behavior_State::Scripted;
+	}
+
 	const float Courage      = GetTrait(EPS_AI_Behavior_TraitAxis::Courage);
 	const float Aggressivity = GetTrait(EPS_AI_Behavior_TraitAxis::Aggressivity);
 	const float Caution      = GetTrait(EPS_AI_Behavior_TraitAxis::Caution);

Unreal/PS_AI_Agent/Plugins/PS_AI_Behavior/Source/PS_AI_Behavior/Public/PS_AI_Behavior_AIController.h

@@ -59,6 +59,10 @@ public:
 
 	// ─── Configuration ──────────────────────────────────────────────────
 
+	/** If false, the Behavior Tree does NOT start on possess. Call StartBehavior() manually. */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Behavior")
+	bool bAutoStartBehavior = true;
+
 	/** Behavior Tree to run. If null, uses the Profile's DefaultBehaviorTree. */
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Behavior")
 	TObjectPtr<UBehaviorTree> BehaviorTreeAsset;
@@ -107,6 +111,14 @@ public:
 	UFUNCTION(BlueprintCallable, Category = "PS AI Behavior|Blackboard")
 	EPS_AI_Behavior_State GetBehaviorState() const;
 
+	/** Start (or restart) the Behavior Tree. If state is Scripted, transitions to Idle. */
+	UFUNCTION(BlueprintCallable, Category = "PS AI Behavior")
+	void StartBehavior();
+
+	/** Stop the Behavior Tree and enter Scripted state. NPC stays alive and perceptible. */
+	UFUNCTION(BlueprintCallable, Category = "PS AI Behavior")
+	void StopBehavior();
+
 protected:
 	virtual void OnPossess(APawn* InPawn) override;
 	virtual void OnUnPossess() override;
@@ -126,9 +138,6 @@ private:
 	/** Initialize Blackboard with required keys. */
 	void SetupBlackboard();
 
-	/** Start the Behavior Tree (from asset or profile). */
-	void StartBehavior();
-
 	/**
 	 * Attempt to bind to PS_AI_ConvAgent_ElevenLabsComponent if present on the Pawn.
 	 * Uses UObject reflection — no compile-time dependency on PS_AI_ConvAgent.

Unreal/PS_AI_Agent/Plugins/PS_AI_Behavior/Source/PS_AI_Behavior/Public/PS_AI_Behavior_Definitions.h

@@ -43,6 +43,7 @@ enum class EPS_AI_Behavior_State : uint8
 	Fleeing      UMETA(DisplayName = "Fleeing"),
 	TakingCover  UMETA(DisplayName = "Taking Cover"),
 	Dead         UMETA(DisplayName = "Dead"),
+	Scripted     UMETA(DisplayName = "Scripted"),
 };
 
 /**