/* author: YKMoon
 * 状态机
 * 初始化需要手动添加状态信息 AddState
 * Update里面来调用状态机运行StateMachineUpdate
 */
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace YKMoon
{
    public class UFSM
    {
        public FSMUpdateMode updateMode = FSMUpdateMode.Normal;

        protected UFSMCore stateMachine {
            get {
                if(_stateMachine == null) {
                    _stateMachine = new UFSMCore(EarlyGlobalUpdate, LateGlobalUpdate);
                }
                return _stateMachine;
            }
        }
        private UFSMCore _stateMachine;

        public UFSMState currentState { get => stateMachine.currentState; set => stateMachine.currentState = value; }
        public int lastState { get { return stateMachine.lastState; } }
        public int currentStateID { get => stateMachine.currentStateID; set => stateMachine.currentStateID = value; }
        /// <summary>
        /// 添加状态
        /// </summary>
        /// <returns><c>true</c>, 如果添加成功, <c>false</c> 添加失败.</returns>
        /// <param name="stateID">状态ID.</param>
        /// <param name="onEnterState">进入状态时调用</param>
        /// <param name="onUpdate">更新时调用</param>
        /// <param name="onExitState">出状态时调用.</param>
        public bool AddState(int stateID, Action onEnterState, Action<float> onUpdate, Action onExitState)
        {
            return stateMachine.AddState(stateID, onEnterState, onUpdate, onExitState);
        }

        public virtual void Update(float deltaTime, float unscaledDeltaTime)
        {
            if(updateMode == FSMUpdateMode.Normal) {
                stateMachine.StateMachineUpdate(deltaTime);
            } else {
                stateMachine.StateMachineUpdate(unscaledDeltaTime);
            }
        }

        protected virtual void EarlyGlobalUpdate(float deltaTime) { }
        protected virtual void LateGlobalUpdate(float deltaTime) { }

        public virtual void Reg()
        {
            UFSMManager.Reg(this);
        }

        public virtual void UnReg()
        {
            UFSMManager.UnReg(this);
        }
    }
}