using UnityEngine;

namespace OHM.UnityToolkit.FSM
{
	public class FiniteStateMachine<StateType> where StateType : StateBase<StateType>
	{
		private float _currentStateStartTime;

		public StateType CurrentState { get; private set; }

		public void SetState(StateType state)
		{
			if (state == null)
			{
				return;
			}
			if (CurrentState != null)
			{
				CurrentState.Leave();
			}
			_currentStateStartTime = Time.time;
			CurrentState = state;
			state.Enter();
		}

		public void Update()
		{
			if (CurrentState == null)
			{
				return;
			}
			CurrentState.Update();
			if (CurrentState == null || CurrentState.NextState == null)
			{
				return;
			}
			if (Time.time - _currentStateStartTime >= CurrentState.MaxDuration)
			{
				SetState(CurrentState.NextState as StateType);
			}
		}

		public float GetCurrentStateDuration()
		{
			return Time.time - _currentStateStartTime;
		}
	}
}