using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
using static UnityEngine.EventSystems.ExecuteEvents;

public class UIButtonDouble : Button
{
    public int ExecuteCount = 1;
    public int curExecuteCount = 0;
    private ButtonClickedEvent m_OnDown = new ButtonClickedEvent();
    private ButtonClickedEvent m_OnUp = new ButtonClickedEvent();
    PointerEventData _pointerEventData;
    public PointerEventData PointerEventData => _pointerEventData;
    public ButtonClickedEvent onDown
    {
        get { return m_OnDown; }
        set { m_OnDown = value; }
    }

    public ButtonClickedEvent onUp
    {
        get { return m_OnUp; }
        set { m_OnUp = value; }
    }
    public override void OnPointerClick(PointerEventData eventData)
    {
        RaycastThrough(eventData, pointerClickHandler);
        base.OnPointerClick(eventData);
    }

    public override void OnPointerDown(PointerEventData eventData)
    {
        RaycastThrough(eventData, pointerDownHandler);
        m_OnDown.Invoke();
        base.OnPointerDown(eventData);
    }
    public override void OnPointerUp(PointerEventData eventData)
    {
        RaycastThrough(eventData, pointerUpHandler);
        m_OnUp.Invoke();
        base.OnPointerUp(eventData);
    }
    public void RaycastThrough<T>(BaseEventData baseEventData, EventFunction<T> eventFunction) where T : IEventSystemHandler
    {
        _pointerEventData = (PointerEventData)baseEventData;

        List<RaycastResult> raycastResults = new List<RaycastResult>();
        //当前处理的gameobject
        GameObject currentObj = gameObject ?? _pointerEventData.pointerDrag;
        //获取当前射线检测到的所有结果
        EventSystem.current.RaycastAll(_pointerEventData, raycastResults);
        curExecuteCount = 0;
        bool isExecute = false;
        for (int i = 0; i < raycastResults.Count; i++)
        {
            //}
            //foreach (var item in raycastResults)
            //{
            var item = raycastResults[i];
            GameObject nextObj = item.gameObject;
            if (nextObj != null && nextObj == currentObj)
            {
                isExecute = true;
            }
            if (isExecute && nextObj != null && nextObj != currentObj)
            {
                GameObject excuteObj = GetEventHandler<T>(nextObj);
                if (excuteObj != null && excuteObj != currentObj)
                {
                    //执行下一层事件,如果你还需要继续执行下面层UI事件可以不return，我这里只检测下一层的，所以我循环一次就直接return
                    Execute(excuteObj, _pointerEventData, eventFunction);
                }
                curExecuteCount++;
                if (curExecuteCount >= ExecuteCount)
                {
                    return;
                }

            }
        }

    }
}