using System.Collections;
using System.Collections.Generic;
using UnityEngine;

// 角色状态机
[DisallowMultipleComponent]
public class UnitState : UnitComponent
{
    public enum EUnitState
    {
        Idle 	    ,
        Move 	    ,
        Spawn 	    ,
        Die 	    ,
        Dead 	    ,
        Skill 	    ,
        // 		    
        HitAir 	    ,
        HitAirHit   ,
        Knockdown   ,
        //		    
        HitGuard    ,
        //		    
        Walk	    ,
		// 		    
		Rise	    ,
		// 		    
		Jump	    ,
		// 转身
		Turn		,
    }

    [SerializeField] private EUnitState m_State;
    public EUnitState CurrentState { get { return m_State; } }

    private delegate void ExitStateHandler(EUnitState nextState);
    private delegate void EnterStateHandler(EUnitState prevState);

    private Dictionary<EUnitState, ExitStateHandler> m_ExitStateHandlerDic = new Dictionary<EUnitState, ExitStateHandler>();

	public override void Initialize()
	{
		base.Initialize();

		InitState(); 
	}

	#region state param
	public struct IdleParam {}

    public struct MoveParam
    {
		public bool isRight;
		public string key;
    }

    public struct SkillParam
    {

    }

	public struct JumpParam
	{ }

	public struct TurnParam
	{
		EUnitState nextState;
	}

    #endregion  

    void InitState()
    {
        m_ExitStateHandlerDic.Add(EUnitState.Idle, OnIdleExit);
        m_ExitStateHandlerDic.Add(EUnitState.Move, OnMoveExit);
		m_ExitStateHandlerDic.Add(EUnitState.Skill, OnSkillExit);
		m_ExitStateHandlerDic.Add(EUnitState.Jump, OnJumpExit);
	}

	public void ChangeState<T>(EUnitState nextState, T param = default, bool bForce = false)
    {
        if (!IsChange(nextState, bForce))
            return;

		LogHelper.Log("UnitState: " + m_State.ToString() + " -> " + nextState.ToString());

		StopAllCoroutines();

		EUnitState prevState = m_State;
		if (m_ExitStateHandlerDic.ContainsKey(m_State))
		{
			m_ExitStateHandlerDic[m_State](nextState);
		}
		m_State = nextState;

		StartCoroutine(m_State.ToString(), param);
	}

	bool IsChange(EUnitState newState, bool bForce)
    {
        if (newState != m_State || bForce)
            return true;
        return false;
    }

    #region Idle

	IEnumerator Idle(IdleParam param)
    {
		m_Owner.unitAnimation.Play(UnitAnimation.EAnimState.Idle);
		yield return null;
	}

    void OnIdleExit(EUnitState nextState)
    {

    }
    #endregion

    #region Move 
	IEnumerator Move(MoveParam param)
    {
		if (m_Owner.isTowardRight && !param.isRight
		|| !m_Owner.isTowardRight && param.isRight)
		{
			//m_Owner.unitAnimation.Play(UnitAnimation.EAnimState.Turn);
			//yield return new WaitForActionReachEnd(m_Owner.unitAnimation);
			//if (param.isRight)
			//	m_Owner.transform.rotation = Quaternion.Euler(0, 0, 0);
			//else
			//	m_Owner.transform.rotation = Quaternion.Euler(0, 180, 0);
			m_Owner.transform.rotation = Quaternion.Euler(0, param.isRight ? 0 : 180, 0);
		}
		if(Input.GetKey(param.key))
			m_Owner.unitAnimation.Play(UnitAnimation.EAnimState.Move);
		while (Input.GetKey(param.key))
		{
			yield return null;
		}
		ChangeState(EUnitState.Idle, new IdleParam());
    }

    void OnMoveExit(EUnitState nextState)
    {

    }

	#endregion

	#region Skill

	IEnumerator Skill(SkillParam param)
	{
		m_Owner.unitAnimation.Play(UnitAnimation.EAnimState.Attack);
		yield return new WaitForActionReachEnd(m_Owner.unitAnimation);
		ChangeState(EUnitState.Idle, new IdleParam());
	}

	void OnSkillExit(EUnitState next)
	{

	}

	#endregion

	#region Jump 

	IEnumerator Jump(JumpParam param)
	{
		m_Owner.unitAnimation.Play(UnitAnimation.EAnimState.Jump);
		yield return new WaitForActionReachEnd(m_Owner.unitAnimation);
		ChangeState<IdleParam>(EUnitState.Idle);
	}

	void OnJumpExit(EUnitState next)
	{

	}

	#endregion

}