using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;

public class UIDragableObj : MonoBehaviour, IDragHandler, IPointerDownHandler, IPointerUpHandler
{
    [AutoUI]
    public Vector2 position;
    protected Vector2 error_pos;

    protected RectTransform rectransfrom;

    protected void Awake()
    {
        rectransfrom = GetComponent<RectTransform>();
    }

    // Use this for initialization
    void Start () {
		
	}
	
	// Update is called once per frame
	protected void Update () {
        rectransfrom.anchoredPosition = position;
    }

    public void OnPointerDown(PointerEventData eventData)
    {
        print("OnPointerDown");
        Vector2 n_position = eventData.position - new Vector2(Screen.width, Screen.height) / 2;
        error_pos = n_position - position;

    }

    public void OnDrag(PointerEventData eventData)
    {
        Vector2 n_position = eventData.position;

        position = n_position - new Vector2(Screen.width, Screen.height) / 2 - error_pos;
    }


    public void OnPointerUp(PointerEventData eventData)
    {
        error_pos = Vector2.zero;
    }
}