using System;
using AX.InputSystem;
using UnityEngine;
using UnityEngine.EventSystems;

/// <summary>
/// UI拖拽脚本，想拖拽谁就挂在谁身上。必须保证该UI有Raycast Target组件，并使其保持开启状态。
/// </summary>
[RequireComponent(typeof(CreateStaticObjID))]
[RequireComponent(typeof(BaseGameObjInfo))]
public class OnDragPanel : MonoBehaviour, IDragHandler,IBeginDragHandler,IEndDragHandler
{
    private RectTransform canvasRect;
    private RectTransform transRect;
    private Vector2 localPos;
    private Vector2 offSet;
    private void Start()
    {
        canvasRect = GameObject.Find("Canvas").GetComponent<RectTransform>();
        transRect = GetComponent<RectTransform>();
        offSet= localPos = Vector3.zero;
    }

    public void OnBeginDrag(PointerEventData eventData)
    {
        if (eventData.button != PointerEventData.InputButton.Left) return;//不是左键按下就不能拖拽
        var arg = new OnDragCmdArgs();
        arg.position = eventData.position;
        RegisterUIInputEvent.RegisterUIInputHistory(gameObject, this.GetType().Name, "BeginDrag", arg);
        BeginDrag(arg);
    }

    public void BeginDrag(OnDragCmdArgs args)
    {
        if (RectTransformUtility.ScreenPointToLocalPointInRectangle(canvasRect, args.position, canvasRect.GetComponent<Canvas>().worldCamera, out localPos))
        {
            offSet = localPos - new Vector2(transRect.localPosition.x, transRect.localPosition.y);
            InputManager.isDargUI = true;
            transform.SetAsLastSibling();
        }
    }

    public void OnDrag(PointerEventData eventData)
    {
        if (eventData.button != PointerEventData.InputButton.Left) return;//不是左键按下就不能拖拽
        var arg = new OnDragCmdArgs();
        arg.position = eventData.position;
        arg.currentCursorPos = Input.mousePosition;
        //arg.EventCamera = eventData.pressEventCamera;  ********摄像机不能记录**********
        RegisterUIInputEvent.RegisterUIInputHistory(gameObject, this.GetType().Name, "Drag", arg);
        Drag(arg);
    }

    public void Drag(OnDragCmdArgs args)
    {
        if (GameSettings.othersSettings.playState == PlayState.Playing)
        {
            CursorManager.GetInstance.SetClick(args);
        }
        if (RectTransformUtility.ScreenPointToLocalPointInRectangle(canvasRect, args.position, canvasRect.GetComponent<Canvas>().worldCamera, out localPos))
        {
            transRect.localPosition = localPos - offSet;
        }

    }

    public void OnEndDrag(PointerEventData eventData)
    {
        if (eventData.button != PointerEventData.InputButton.Left) return;//不是左键按下就不能拖拽
        var arg = new OnDragCmdArgs();
        arg.currentCursorPos = Input.mousePosition;
        RegisterUIInputEvent.RegisterUIInputHistory(gameObject, this.GetType().Name, "EndDrag", arg);
        EndDrag(arg);
    }

    public void EndDrag(CmdArgs args)
    {
        if (GameSettings.othersSettings.playState == PlayState.Playing)
        {
            CursorManager.GetInstance.SetClick(args);
        }
        InputManager.isDargUI = false;
    }
}