using Thousandto.Core.Base;
using Thousandto.Core.Support;
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace Thousandto.Code.Logic
{
    /// <summary>
    /// 游戏状态Machine 
    /// </summary>
    public class StateMachine
    {
        #region//私有变量
        //状态拥有者
        private IStateSystem _owner = null;
        //前一状态
        private IGameState _prevState = null;
        //当前状态
        private IGameState _curState = null;
        //下一状态
        private IGameState _nextState = null;
        //所有状态集合
        private IGameState[] _statesCache = null;
        #endregion

        #region//构造函数
        public StateMachine(IStateSystem owner)
        {
            _owner = owner;
            Initialize();
        }
        #endregion

        #region//私有函数
        public void Initialize()
        {
        }
        #endregion

        #region//公共函数
        //获取前一状态
        public IGameState GetPrevState()
        {
            return _prevState;
        }
        //获取当前状态
        public IGameState GetCurState()
        {
            return _curState;
        }
        //获取下一状态
        public IGameState GetNextState()
        {
            return _nextState;
        }
        public void HandlerMessage(object arg)
        {
            if (_curState != null)
                _curState.HandlerMessage(arg);
        }
        //切换状态
        public void ChangeState(int stateId, object arg = null)
        {
            try
            {
                IGameState newState = _owner.GetStateById(stateId);
                if (newState != null && newState.Check(_prevState))
                {
                    _prevState = _curState;
                    _nextState = newState;
                    _nextState.Arg = arg;
                    //退出前一状态
                    if (_prevState != null)
                        _prevState.Leave();
                    //进入下一状态
                    if (_nextState != null)
                    {
                        _curState = _nextState;
                        _curState.Enter();
                    }
                }
            }
            catch (Exception e)
            {
                UnityEngine.Debug.LogError(string.Format("游戏状态切换失败!!!!{0}", e));
            }
        }

        //判断当前状态是否是传入stateId对应的状态
        public bool IsState(int stateId)
        {
            if (_curState != null)
            {
                return _curState.GetStateId() == stateId;
            }
            return false;
        }

        public bool Update(float dt)
        {
            if (_curState != null)
            {
                _curState.Update(dt);
                return true;
            }
            return false;
        }

        public void Clear()
        {
            _prevState = null;
            _curState = null;
            _nextState = null;
            _statesCache = null;
        }
        #endregion
    }
}