using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
/*******************************************************************************
*Create By CG
*Function 
*******************************************************************************/
namespace Test
{
	public class Test2 : MonoBehaviour
	{
        public GameObject uiElement;

        void Update()
        {
            //if (IsMouseOverUI(uiElement))
            //{
            //    Debug.Log("鼠标在UI上");
            //}

            //if(RectTransformUtility.RectangleContainsScreenPoint(uiElement.GetComponent<RectTransform>(), Input.mousePosition, Camera.main))
            // {
            //     Debug.Log("鼠标在UI上");
            // }

            //ClickUI();

            GetOverUI(GameObject.Find("Canvas"));
        }

        private bool IsMouseOverUI(GameObject uiElement)
        {
            PointerEventData pointerEventData = new PointerEventData(EventSystem.current);
            pointerEventData.position = Input.mousePosition;
            if (EventSystem.current.IsPointerOverGameObject())
            {
                return true;
            }
            return false;
        }

        /// <summary>
        /// 获取鼠标停留处UI
        /// </summary>
        /// <param name="canvas"></param>
        /// <returns></returns>
        public GameObject GetOverUI(GameObject canvas)
        {
            PointerEventData pointerEventData = new PointerEventData(EventSystem.current);
            pointerEventData.position = Input.mousePosition;
            GraphicRaycaster gr = canvas.GetComponent<GraphicRaycaster>();
            List<RaycastResult> results = new List<RaycastResult>();
            gr.Raycast(pointerEventData, results);
            if (results.Count != 0)
            {
                foreach (var item in results)
                {
                    Debug.Log(item.gameObject.name);
                }
                return results[0].gameObject;
            }
            return null;
        }



        List<RaycastResult> list = new List<RaycastResult>();
        //场景中的EventSystem
        

        private void ClickUI()
        {
            //鼠标位置
            PointerEventData eventData = new PointerEventData(EventSystem.current);
            eventData.position = Input.mousePosition;

            EventSystem.current.RaycastAll(eventData, list);

            foreach (var item in list)
            {
                if (item.gameObject != null)
                {
                    Debug.Log(item.gameObject.name);
                    //获取父类中事件注册接口
                    //当然可以细分为IPointerClickHandler, IBeginDragHandler之类细节一点的，各位可以自己取尝试
                    //var go = ExecuteEvents.GetEventHandler<IPointerClickHandler>(item.gameObject);
                    //var go1 = ExecuteEvents.GetEventHandler<IEventSystemHandler>(item.gameObject);
                }
            }
        }
    }
}