using EasyInject.Attributes;
using System;
using System.Collections.Generic;
using UnityEngine;
/// <summary>
/// 程序状态机
/// </summary>
[Component]
public  class ApplicationStateMachine
{
    private List<IProcessState> processStates;
    private static IProcessState currentProcess ;

    private static ApplicationStateMachine stateMachine;

    public  event ProcessCompleted ProcessCompletedEvent;
    public delegate void ProcessCompleted();
    public ApplicationStateMachine()
    {
        stateMachine = this;
    }

    private static void SetCurrentProcess(IProcessState current)
    {
        current.IsExecuteProcess = true;
        currentProcess = current;

        int index = stateMachine.processStates.IndexOf(currentProcess);
       
        try {
            current.OnEnter();
        }catch (Exception ex)
        {
            Debug.LogError(ex.Message);
        }
        //已经是最后流程了，触发完成事件
        if (index == stateMachine.processStates.Count - 1)
        {
            stateMachine.ProcessCompletedEvent?.Invoke();
        }

    }

    /// <summary>
    /// 切换下一个流程，根据流程优先级切换
    /// </summary>
    public static void Chanage(IProcessState currentProcess)
    {
        int index = stateMachine.processStates.IndexOf(currentProcess) + 1;
        if (stateMachine.processStates.Count != index && stateMachine.processStates[index] != null)
        {
            currentProcess.IsExecuteProcess = false;
            currentProcess.OnExit();
            SetCurrentProcess(stateMachine.processStates[index]);
        }
    }
    public void OnInit()
    {
        Debug.Log("初始化状态机");
        processStates = ApplicationBoot.Instance.GetBeans<IProcessState>();
        if (processStates != null && processStates.Count > 0)
        {
            processStates.Sort((a, b) => a.Priority - b.Priority);
            SetCurrentProcess(processStates[0]);
        }
    }
    /// <summary>
    /// 每帧更新状态机
    /// </summary>
   public void OnUpdate()
    {
        if (currentProcess != null)
        {
            try
            {
                currentProcess.OnUpdate();
            }
            catch (Exception ex)
            {
                Debug.LogError(ex.Message);
            }
         
        }
    }
}