using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
namespace LoyalSoftSDK
{
    public class DragUtils : MonoBehaviour,IBeginDragHandler, IDragHandler, IEndDragHandler,IPointerDownHandler,IPointerUpHandler
    {
        private RectTransform rectTransform;
        private RectTransform cavasRectTransform;
        private Vector2 starPoint;
        private Vector2 endPoint;
        private bool isClick=true;
        public delegate void EndDragHandler();
        public EndDragHandler OnEndDragHandler;

        public delegate void ClickHandler();
        public ClickHandler OnClickHandler;
        public delegate void BeginDragHandler();
        public BeginDragHandler OnBeginDragHandler;
        void Start()
        {
            rectTransform = this.gameObject.transform.parent.GetComponent<RectTransform>();
            cavasRectTransform = UIFormManager.GetInstance().canvasTransform.gameObject.GetComponent<RectTransform>();
        }

        public void OnBeginDrag(PointerEventData eventData)
        {
            //Debug.Log(eventData.position);
            if(OnBeginDragHandler!=null)
            {
                OnBeginDragHandler.Invoke();
            }
            isClick = false;
            //Debug.Log("拖拽开始");
        }

        public void OnDrag(PointerEventData eventData)
        {
            Vector3 globalMousePos;
            if (RectTransformUtility.ScreenPointToWorldPointInRectangle
                (cavasRectTransform, eventData.position, eventData.pressEventCamera, out globalMousePos))
            {
                rectTransform.position = globalMousePos;
                rectTransform.rotation = cavasRectTransform.rotation;
            }


        }

        public void OnEndDrag(PointerEventData eventData)
        {
            //Debug.Log(eventData.position);

            //Debug.Log("拖拽停止");
            if (OnEndDragHandler != null)
            {
                OnEndDragHandler.Invoke();
            }





        }
        public void OnPointerDown(PointerEventData eventData)
        {
            //Debug.Log("按下");
           // starPoint = eventData.position;
            isClick = true;


        }

        public void OnPointerUp(PointerEventData eventData)
        {
            //Debug.Log("抬起");
            //endPoint = eventData.position;
            //float dragDistance = Mathf.Pow(endPoint.x - starPoint.x, 2) + Mathf.Pow(endPoint.y - starPoint.y, 2);
           
            //if(dragDistance<=100)
            //{
               

            //}
            if(isClick)
            {
                if (OnClickHandler != null)
                {
                    OnClickHandler.Invoke();
                }
            }
          
          

        }
        // Use this for initialization


        // Update is called once per frame
        void Update()
        {

        }

       
    }

}