using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;

public class VirtualPad : Singleton<VirtualPad>, IDragHandler, IPointerUpHandler, IPointerDownHandler
{
    [SerializeField]
    private Image Controller, stick;

    private Canvas canvas;
    private Camera uiCamera;
    private RectTransform canvasRect;

    private bool istouch = false;
    private bool isDrag = false;
    private float fdt;

    private Vector2 saveVec;
    private Vector2 resultVec;
    private Vector2 MoveVec;
    private Vector2 DragVec;

    private void Awake()
    {
        _instance = this;
        canvas = transform.parent.GetComponent<Canvas>();
        canvasRect = canvas.GetComponent<RectTransform>();
    }

    private void Update()
    {
        if (isDrag)
        {
            BattleMgr.MoveToDir(MoveVec);
        }
    }

    public void OnDrag(PointerEventData eventData)
    {
        if(BattleMgr.CurrentBattleType != BattleMgr.BattleType.Pvp)
        {
            if (!isDrag)
            {
                Controller.enabled = true;
                stick.enabled = true;
            }
            isDrag = true;
            RectTransformUtility.ScreenPointToLocalPointInRectangle(canvasRect, eventData.position, uiCamera, out DragVec);
            resultVec = DragVec - saveVec;
            MoveVec = resultVec.normalized;
            fdt = Vector2.Distance(saveVec, DragVec) < 82f ? Vector2.Distance(saveVec, DragVec) : 82f;
            stick.rectTransform.anchoredPosition = saveVec + (MoveVec * fdt);
        }
    }

    public void OnPointerUp(PointerEventData eventData)
    {
        istouch = false;
        isDrag = false;
        Controller.enabled = false;
        stick.enabled = false;
    }

    public void OnPointerDown(PointerEventData eventData)
    {
        RectTransformUtility.ScreenPointToLocalPointInRectangle(canvasRect, eventData.position, uiCamera, out saveVec);
        Controller.rectTransform.anchoredPosition = saveVec;
        stick.rectTransform.anchoredPosition = saveVec;
        istouch = true;
    }

    public static bool isTouchScreen()
    {
        return Instance.istouch;
    }

    public static void setCamera(Camera uicam)
    {
        Instance.uiCamera = uicam;
    }

    public static Vector2 GetPointDirection()
    {
        return new Vector2(Instance.resultVec.x >= 0 ? 1 : -1, Instance.resultVec.y >= 0 ? 1 : -1);
    }
}