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

public class ModelCameraCtrl : MonoBehaviour
{
    public static ModelCameraCtrl _Instance;

    public Camera _camera;

    public float smoothSpeed = 5f; // 摄像头平滑移动的速度
    public float scrollSensitivity = 65f; // 鼠标滚轮的灵敏度
    public float rotateSpeed =3f;
    public float translateSpeed = 0.8f;
    public float minDistance = 5f; // 摄像头与目标对象的最小距离
    public float maxDistance = 50f; // 摄像头与目标对象的最大距离

    public float currentDistance; // 当前摄像头与目标对象的距离
    private Vector3 offset; // 摄像头与目标对象的偏移量
    private Vector3 velocity = Vector3.zero; // 摄像头移动的速度

    public float rotateYAngle = 0.0f;
    public float rotateXAngle = 0.0f;

    bool isRotate = false;

    bool onUI = false;

    private void Awake()
    {
        _Instance = this;
    }

    public void SetCameraActive(bool flag)
    {
        _camera.enabled = flag;
    }

    private void Start()
    {
        SetCameraActive(false);
        // 初始化当前距离为初始偏移量的距离
        currentDistance = Vector3.Distance(_camera.transform.position, this.transform.position);
        // 确保初始距离在允许的范围内
        currentDistance = Mathf.Clamp(currentDistance, minDistance, maxDistance);

        offset = _camera.transform.position - this.transform.position;
    }

    public void SetCameraPos(Transform pos,float distance,Vector2 rota)
    {
        currentDistance = distance;
        this.transform.position = pos.position;
        rotateXAngle = rota.x;
        rotateYAngle = rota.y;
    }

    void LateUpdate()
    {
        onUI = false;
        if (IsPointerOverUIElement()) onUI = true;

        // 鼠标滚轮控制摄像头远近
        if (Input.GetAxis("Mouse ScrollWheel") != 0 && onUI)
        {
            // 更新当前距离
            currentDistance -= Input.GetAxis("Mouse ScrollWheel") * scrollSensitivity;
            // 确保距离在允许的范围内
            currentDistance = Mathf.Clamp(currentDistance, minDistance, maxDistance);


            //this.GetComponent<DepthFog>().Height = 400000 / currentDistance;
        }

        translateSpeed = currentDistance / 600f;

        scrollSensitivity = currentDistance / 16.0f * currentDistance / 16.0f;

        scrollSensitivity = Mathf.Clamp(scrollSensitivity, 10, 4000);

        if (Input.GetMouseButton(0)&& onUI)
        {
            rotateXAngle -= Input.GetAxis("Mouse Y") * rotateSpeed;
            rotateYAngle += Input.GetAxis("Mouse X") * rotateSpeed;
            isRotate = true;
        }
        else
        {
            isRotate = false;
        }

        if (isRotate)
        {
            Blink();
        }
        else
        {
            // 计算目标位置
            Vector3 targetPosition = this.transform.position + Quaternion.Euler(new Vector3(rotateXAngle, rotateYAngle, 0)) *
                offset.normalized * currentDistance;

            // 摄像头平滑移动到目标位置
            _camera.transform.position = Vector3.Lerp(_camera.transform.position, targetPosition, Time.deltaTime * smoothSpeed);
        }
    }

    private bool IsPointerOverUIElement()
    {
        // 检查当前鼠标位置是否在 UI 上
        return EventSystem.current.IsPointerOverGameObject();
    }

    public void Blink()
    {
        // 计算目标位置
        Vector3 targetPosition = this.transform.position +
                                 Quaternion.Euler(new Vector3(rotateXAngle, rotateYAngle, 0)) * offset.normalized *
                                 currentDistance;

        // 摄像头平滑移动到目标位置
        _camera.transform.position = targetPosition;

        //摄像头朝向目标对象
        _camera.transform.transform.rotation =
            Quaternion.LookRotation(this.transform.position - _camera.transform.position, Vector3.up);
    }
}