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


public class CameraOp : MonoBehaviour, IBeginDragHandler, IDragHandler,IPointerDownHandler
{
    public Transform tagertTrns;
    public Camera mainCamera;
    public float scaleSpeed = 0.5f;
    public float rotateSpeed = 0.05f;
    public float moveSpeed = 0.01f;
    // Start is called before the first frame update
    void Start()
    {
        
    }

    // Update is called once per frame
    void Update()
    {
        float offset = Input.GetAxis("Mouse ScrollWheel");
        if (Input.GetAxis("Mouse ScrollWheel") != 0)
        {
            Debug.Log("ScrollWheel<0");
            float scale = Input.GetAxis("Mouse ScrollWheel")*scaleSpeed;
           // float z = mainCamera.transform.position.z + scale;
            //z = Mathf.Clamp(z, 1.52f, 3.3f);
            mainCamera.transform.position += mainCamera.transform.forward*scale;
            //tagertTrns.transform.localScale = new Vector3(scale, scale, scale);

        }
    }

    private Vector2 startPostion;
    public void OnBeginDrag(PointerEventData eventData)
    {
        startPostion = eventData.position;
    }

    public void OnDrag(PointerEventData eventData)
    {
        if (eventData.button == PointerEventData.InputButton.Left)
        {
            tagertTrns.Rotate(new Vector3(0, -eventData.delta.x, 0) * rotateSpeed, Space.World);
            //mainCamera.transform.RotateAround(tagertTrns.position, Vector3.up, eventData.delta.x * rotateSpeed);
            mainCamera.transform.RotateAround(tagertTrns.position, Vector3.right, -eventData.delta.y * rotateSpeed);
        }
        else if (eventData.button == PointerEventData.InputButton.Right)
        {
            mainCamera.transform.position += new Vector3(-eventData.delta.x, -eventData.delta.y, 0) * moveSpeed;
        }
        
    }



    //data是鼠标在rawImage上交互的PointEventData数据
    //rectTransform是RenderTexture所在的rawImage的RectTransform
    //rtCamera是渲染3D模型的摄像机
    //返回的obj就是轮胎，窗、门等物体
    public GameObject GetHitObj(PointerEventData data)
    {
        GameObject obj = null;
        var rect= this.gameObject.GetComponent<RectTransform>();
        var pos = (data.position - (Vector2)rect.position) / rect.lossyScale - rect.rect.position;
        
        var rate = pos / rect.rect.size;
        var ray = mainCamera.ViewportPointToRay(rate);
        RaycastHit raycastHit;
        
        if (Physics.Raycast(ray, out raycastHit))
        {
            Debug.Log(raycastHit.transform.name);
            obj = raycastHit.transform.gameObject;
        }
        Debug.DrawRay(mainCamera.transform.position, ray.direction,Color.red);
        return obj;

    }

    public void OnPointerDown(PointerEventData eventData)
    {
        
       // GetHitObj(eventData);
    }
}