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

//流程中步骤节点控制基类  管理所有的前置和后置步骤 定义步骤激活和步骤完成行为
public abstract class StepNodeBase : MonoBehaviour
{
    protected ProcessEnum currentProcess;//流程名称
    [SerializeField]
    protected bool autoFinishedStep;//激活时自动完成的步骤

    [SerializeField]
    string nodeName;
    /// <summary>
    /// 节点名称
    /// </summary>
    public string NodeName
    {
        get
        {
            return nodeName;
        }
    }

    //[HideInInspector]
    //节点完成情况
    public NodeFinishState stepState;
    public NodeFinishState StepState
    {
        get
        {
            return stepState;
        }
    }

    //当前节点激活状态  避免重复激活
    protected NodeActiceState nodeActiceState;

    public NodeActiceState NodeActiceState
    {
        get
        {
            return nodeActiceState;
        }
    }

    /// <summary>
    /// 前置节点  所有的前置节点满足后 启动本节点
    /// </summary>
    public List<StepNodeBase> preconditionNodes = new List<StepNodeBase>();

    /// <summary>
    /// 后置节点 本节点完成后 通知后置节点 
    /// </summary>
    public List<StepNodeBase> postpositionNodes = new List<StepNodeBase>();


    public event UnityAction NodeFinished;//步骤完成
    // Start is called before the first frame update
    protected virtual void Awake()
    {
        ProcessManager.Instance.AddStep(this);//将操作物体加入当前流程控制器
    }

    /// <summary>
    /// 前置节点通知完成时
    /// </summary>
    public void PreNodeFinished(StepNodeBase stepNode = null)
    {
        bool hasPNunFinised = false;
        for (int i = 0; i < preconditionNodes.Count; i++)
        {
            if (preconditionNodes[i].StepState == NodeFinishState.unFinished)
            {
                hasPNunFinised = true;
                break;
            }
        }
        if (!hasPNunFinised)//前置节点都完成了 或者没有前置节点
        {
            stepState = NodeFinishState.unFinished;
            Active();
            Debug.Log($"{currentProcess}流程，前置条件均满足,{nodeName}激活");
        }
    }

    /// <summary>
    /// 开始前先设置 流程 避免某些节点激活时自动完成 导致后续流程异常
    /// </summary>
    /// <param name="processEnum"></param>
    public void SetProcess(ProcessEnum processEnum)
    {
        currentProcess = processEnum;
    }

    /// <summary>
    /// 流程开始时执行  
    /// </summary>
    /// <param name="active"></param>
    public void ProcessStart()
    {
        stepState = NodeFinishState.unFinished;//开始时默认所有的 步骤均为完成
        if (preconditionNodes.Count == 0)//无前置节点流程开始时 直接激活
        {
            //Debug.Log($"{currentProcess}流程开始时{nodeName}激活");
            Active();
        }
    }

    //流程结束时
    public void ProcessStop()
    {
        UnActive();
    }

    /// <summary>
    /// 节点激活时执行
    /// </summary>
    protected abstract void Active();

    /// <summary>
    /// 退出激活状态时执行
    /// </summary>
    protected abstract void UnActive();

    /// <summary>
    /// 节点行为完成 退出激活状态 通知后续节点 由节点行为结束时调用
    /// </summary>
    protected virtual void NodeFinised()
    {
        Debug.Log(NodeName + "步骤完成");
        stepState = NodeFinishState.finished;
        UnActive();
        NodeFinished?.Invoke();//节点完成事件 通知外部的事件
        ProcessManager.Instance.RecordFinisedStep(NodeName);//通知管理器本节点完成
        //尝试启动后续节点
        for (int i = 0; i < postpositionNodes.Count; i++)
        {
            postpositionNodes[i].PreNodeFinished(this);
        }
    }

}

//节点完成状态
public enum NodeFinishState
{
    /// <summary>
    /// 已完成
    /// </summary>
    finished,

    /// <summary>
    /// 未完成
    /// </summary>
    unFinished,
}

/// <summary>
/// 节点激活状态
/// </summary>
public enum NodeActiceState
{
    /// <summary>
    /// 已激活状态
    /// </summary>
    active,

    /// <summary>
    /// 未激活状态
    /// </summary>
    unActice,
}