UnrealFightingFramework/Source/UnrealFightingEngine/State/FEState.h

// Unreal Fighting Engine by Kevin Poretti

#pragma once

// UE includes
#include "CoreMinimal.h"

#include "FEState.generated.h"

/**
 *	A state is an object that provides rules and conditions for when a state can be transitioned into
 *	and logic to run when the state is entered, exited, and active.
 */
UCLASS()
class UNREALFIGHTINGENGINE_API UFEState : public UObject
{
	GENERATED_BODY()

public:

	/**
	 *	Initializes pointers to what owns this state and what avatar this state represents.
	 *
	 *  @param InOwner Actor that owns this state machine.
	 *	@param InAvatar Actor that this state machine represents.
	 */
	virtual void InitActorInfo(AActor* InOwner, AActor* InAvatar);

	/** Name of this state */
	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category="UFE|State")
	FName Name;

	/** Conditions that need to be met in order for this state to be transitioned into */
	UPROPERTY(EditAnywhere)
	TArray<uint8> EntryConditions;

	/** What is this state's category. Used for determining what types of state can prematurely cancel this one. */
	UPROPERTY(EditAnywhere)
	uint8 StateType;

	/** How many ticks have elapsed since this state was entered */
	UPROPERTY(BlueprintReadOnly, Category="UFE|State")
	int32 TicksInState;

	/**
	 *	Called whenever this state is transitioned into.
	 *
	 *	Resets TicksInState and calls appropriate Blueprint hooks
	 */
	void Enter();

	/**
	 *	Called whenever this state is transitioned out of into a new state.
	 */
	void Exit();

	/**
	 *	Called whenever this state is active and the game logic ticks.
	 *
	 *	Increments TicksInState and calls appropriate Blueprint hooks.
	 *
	 *	@param OneFrame the time that elapses during one fixed tick
	 */
	void Update(float OneFrame);

    /**
     *	Blueprint hook that is called whenever this state is transitioned into
     */
	UFUNCTION(BlueprintNativeEvent, Category="UFE|State|Events")
	void OnEnter();

	/**
	 *	Blueprint hook that is called whenever this state is transitioned out of into a new state
	 */
	UFUNCTION(BlueprintNativeEvent, Category="UFE|State|Events")
	void OnExit();

	/**
	 *	Blueprint hook that is called whenever this state is active and the game logic ticks
	 *
	 *	@param OneFrame the time that elapses during one fixed tick
	 */
	UFUNCTION(BlueprintNativeEvent, Category="UFE|State|Events")
	void OnUpdate(float OneFrame);

	// UObject interface
	virtual UWorld* GetWorld() const override;
	// End of UObject interface

protected:

	/**
	 *	Actor that owns this state.
	 *	This will typically be a player controller that possesses the avatar.
	 */
	UPROPERTY(BlueprintReadOnly)
	AActor* Owner;

	/**
	 *	The avatar is an actor that this state represents.
	 *	This will typically be a pawn or character.
	 */
	UPROPERTY(BlueprintReadOnly)
	AActor* Avatar;
};