using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Cinemachine;
using System;

public class Cinemachine_2dCon : MonoBehaviour
{
    public float cameraMaxSize;
    public float cameraMinSize;
    public float zoomSpeed;

    public CinemachineVirtualCamera v_cam;
    public Camera m_cam;
    private Transform m_selfTrans;
    private bool m_fingerDown = false;

    //事件，用于开启或关闭摄像逻辑
    public static Action<bool> SetCameraContorl;
    private bool IsCan = true;

    /// <summary>
    /// 单指滑动的手指位置
    /// </summary>
    private Vector3 m_oneFingerDragStartPos;
    /// <summary>
    /// 双指缩放的上一帧的双指距离
    /// </summary>
    private float m_twoFingerLastDistance = -1;


    

    private void Awake()
    {
        m_selfTrans = transform;
    }

    private void Update()
    {
        if (!IsCan)
        {
            return;
        }

#if UNITY_EDITOR || UNITY_STANDALONE
        //// 桌面端：鼠标按下时
        //if (Input.GetMouseButtonDown(0))
        //{
        //    m_fingerDown = true;
        //    m_oneFingerDragStartPos = GetWorldPos(Input.mousePosition); // 获取鼠标按下的起始位置
        //}

        //// 桌面端：鼠标松开时
        //if (Input.GetMouseButtonUp(0))
        //{
        //    m_fingerDown = false;
        //    m_twoFingerLastDistance = -1;
        //}

        // 处理鼠标拖动
        //if (m_fingerDown)
        //{
        //    HandleFingerDragMove(Input.mousePosition);
        //}

        // 处理鼠标滚轮缩放
        //var distance = Input.GetAxis("Mouse ScrollWheel");
        //HandleMouseScrollWheel(distance * 10);

#else
        // 移动端：双指缩放
        if (Input.touchCount == 2)
        {
            HandleTwoFingerScale();
            m_fingerDown = false; // 避免双指缩放时误触单指拖动
        }
        // 移动端：单指滑动
        else if (Input.touchCount == 1)
        {
            Touch touch = Input.touches[0];

            // 手指刚触碰屏幕时
            if (touch.phase == TouchPhase.Began)
            {
                m_fingerDown = true;
                m_oneFingerDragStartPos = GetWorldPos(touch.position); // 获取手指按下的起始位置
            }
            // 手指在屏幕上滑动时
            else if (touch.phase == TouchPhase.Moved)
            {
                HandleFingerDragMove(touch.position); // 处理手指拖动
            }

            m_twoFingerLastDistance = -1; // 复位双指缩放距离
        }
        else
        {
            m_fingerDown = false;
            m_twoFingerLastDistance = -1;
        }
#endif
    }


    /// <summary>
    /// 单指滑动
    /// </summary>
    private void HandleFingerDragMove(Vector2 fingerPos)
    {
        ////滑动差
        //Vector3 cha = m_oneFingerDragStartPos - GetWorldPos(fingerPos);
        //Vector3 newP = m_cam.transform.position;
        //newP.x = newP.x + cha.x;
        //newP.y = newP.y + cha.y;
        //m_selfTrans.position = newP;
    }

    /// <summary>
    /// 双指缩放
    /// </summary>
    private void HandleTwoFingerScale()
    {
        float distance = Vector2.Distance(Input.touches[0].position, Input.touches[1].position);
        if (m_twoFingerLastDistance == -1)
        {
            m_twoFingerLastDistance = distance;
            return; // 避免首次执行时发生误缩放
        }

        // 计算缩放比例
        float scale = 0.1f * (distance - m_twoFingerLastDistance);
        ScaleCamere(scale);

        m_twoFingerLastDistance = distance;
    }

    /// <summary>
    /// 鼠标滚轮缩放
    /// </summary>
    /// <param name="distance"></param>
    //private void HandleMouseScrollWheel(float distance)
    //{
    //    if (0 == distance) return;
    //    ScaleCamere(distance);
    //}

    /// <summary>
    /// 缩放摄像机的视口
    /// </summary>
    /// <param name="scale"></param>
    private void ScaleCamere(float scale)
    {
        v_cam.m_Lens.OrthographicSize -= scale * zoomSpeed;
        if (v_cam.m_Lens.OrthographicSize < cameraMinSize)
        {
            v_cam.m_Lens.OrthographicSize = cameraMinSize;
        }
        if (v_cam.m_Lens.OrthographicSize > cameraMaxSize)
        {
            v_cam.m_Lens.OrthographicSize = cameraMaxSize;
        }
    }

    /// <summary>
    /// 屏幕坐标换算成3D坐标
    /// </summary>
    /// <param name="screenPos">屏幕坐标</param>
    /// <returns></returns>
    Vector3 GetWorldPos(Vector2 screenPos)
    {
        return m_cam.ScreenToWorldPoint(new Vector3(screenPos.x, screenPos.y, Mathf.Abs(m_cam.transform.position.z)));
    }


   //避免内存泄露
    private void OnEnable()
    {
        SetCameraContorl += ToggleCameraControl;
    }
    private void OnDisable()
    {
        SetCameraContorl -= ToggleCameraControl;
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="isActive">禁用或启用</param>
    private void ToggleCameraControl(bool TorF)
    {
        IsCan = TorF;
    }
}