DragHandler

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

public class DragHandler : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
{
    public static GameObject itemBeingDragged;

    #region IBeginDragHandler implementation
    public void OnBeginDrag(PointerEventData eventData)
    {
        itemBeingDragged = gameObject;
        Color c = itemBeingDragged.transform.GetChild (0).GetComponent<Image> ().color;
        c.a = 1;
        itemBeingDragged.transform.GetChild(0).GetComponent<Image> ().color = c;
        itemBeingDragged.GetComponent<Piece>().latestPosition = itemBeingDragged.GetComponent<Piece>().transform.position;
        itemBeingDragged.GetComponent<Piece>().latestParent = itemBeingDragged.GetComponent<Piece>().transform.parent;
        GetComponent<CanvasGroup>().blocksRaycasts = false;
    }
    #endregion

    #region IDragHandler implementation
    public void OnDrag(PointerEventData eventData)
    {
        transform.position = new Vector3(Input.mousePosition.x,Input.mousePosition.y,100f);
    }
    #endregion

    #region IEndDragHandler implementation
    public void OnEndDrag(PointerEventData eventData)
    {
        GetComponent<CanvasGroup>().blocksRaycasts = true;
        if (itemBeingDragged.GetComponent<Piece>().transform.parent == itemBeingDragged.GetComponent<Piece>().latestParent) {
            itemBeingDragged.GetComponent<Piece>().currentLocation = itemBeingDragged.GetComponent<Piece>().transform.position;
            itemBeingDragged.GetComponent<Piece>().targetLocation = itemBeingDragged.GetComponent<Piece>().latestPosition;
            itemBeingDragged.GetComponent<Piece>().animate = true;
            if (itemBeingDragged.GetComponent<Piece>().transform.parent == itemBeingDragged.GetComponent<Piece>().originalParent)
            {
                itemBeingDragged.GetComponent<Piece>().ResetPrefabPiece();
            }
        }
        itemBeingDragged = null;
    }
    #endregion
}