using GCSeries.Core;
using System;
using Unity.Burst.CompilerServices;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
using UnityEngine.UIElements;

public class Show3DCamera : MonoBehaviour
{
    public Vector3 targetPos; // 围绕旋转的目标点
    public float rotateSpeed = 10f; // 旋转速度
    public float moveSpeed = 10f; // 移动速度
    public float distance = 10f; // 相机与目标的距离
    public float distanceMin = 0.2f;
    public float distanceMax = 20f;
    public Vector2 pitchMinMax = new Vector2(-20, 80); // 相机俯仰角范围

    private Vector3 offset; // 相机与目标的偏移量
    private float yaw = 0f; // 偏航角（左右旋转）
    private float pitch = 0f; // 俯仰角（上下旋转）

    public static Show3DCamera instance;

    RectTransform inputRect;
    Camera self;

    private GameObject lastHitObject = null;

    private void Awake()
    {
        instance = this;
        self = transform.GetComponent<Camera>();
        DontDestroyOnLoad(this);
        gameObject.SetActive(false);
    }
    public void Set(Transform target, float rotateSpeed = 10, float moveSpeed = 0.1f, float distance = 0.1f, float pitchMin = -20, float pitchMax = 80, float distanceMin = 0.2f, float distanceMax = 20f, RectTransform inputRect = null)
    {
        if (target == null)
        {
            Debug.LogError("Target is not assigned!");
            return;
        }

        yaw = 0;
        pitch = 0;
        this.inputRect = inputRect;
        this.targetPos = target.transform.position;
        this.rotateSpeed = rotateSpeed;
        this.moveSpeed = moveSpeed;
        this.distance = distance;
        this.distanceMin = distanceMin;
        this.distanceMax = distanceMax;
        this.pitchMinMax = new Vector2(pitchMin, pitchMax);
        // 初始化相机位置
        offset = new Vector3(0, 0, -distance);
        UpdateCameraPosition();
    }



    void Update()
    {
        if (targetPos != null)
        {
            // 按住鼠标左键时旋转相机
            if (Input.GetMouseButton(0))
            {
                RotateCamera();
            }

            // 鼠标滚轮缩放
            float scroll = Input.GetAxis("Mouse ScrollWheel");
            if (scroll != 0)
            {
                ZoomCamera(scroll);
            }


            // 按住鼠标右键时移动目标点
            if (Input.GetMouseButton(1))
            {
                MoveTarget();
            }
            DetectHoveredObject();
        }
    }

    // 检测鼠标悬停的物体
    public void DetectHoveredObject()
    {
        GameObject obj = null;
        Vector2 mousePosition = Input.mousePosition;
        if (inputRect != null)
        {
            var pos = (mousePosition - (Vector2)inputRect.position) / inputRect.lossyScale - inputRect.rect.position;
            mousePosition = pos / inputRect.rect.size;
        }

        var ray = self.ViewportPointToRay(mousePosition);
        RaycastHit raycastHit;
        if (Physics.Raycast(ray, out raycastHit))
        {
            //Debug.Log(raycastHit.transform.name);
            obj = raycastHit.transform.gameObject;


            // 如果击中的物体与上一次击中的物体不同，表示射线进入了新物体
            if (obj != lastHitObject)
            {
                // 触发进入事件
                OnMouseEnterObj(obj);

                // 如果上一次击中的物体不为空，触发离开事件
                if (lastHitObject != null && lastHitObject != obj)
                {
                    OnMouseExitObj(lastHitObject);
                    // 更新上一次击中的物体
                    lastHitObject = obj;
                }

            }
        }
        else
        {
            // 如果射线没有击中任何物体，且上一次击中的物体不为空，触发离开事件
            if (lastHitObject != null)
            {
                OnMouseExitObj(lastHitObject);
                lastHitObject = null;
            }
        }
        Debug.DrawLine(ray.origin, raycastHit.point, Color.red);
    }


    public void OnMouseEnterObj(GameObject obj)
    {
        TipItem tip = obj.GetComponent<TipItem>();
        if (tip != null)
        {
            tip.OnEnter();
        }
    }

    public void OnMouseExitObj(GameObject obj)
    {
        TipItem tip = obj.GetComponent<TipItem>();
        if (tip != null)
        {
            tip.OnExit();
        }

    }

    // 移动目标点
    private void MoveTarget()
    {
        float mouseX = Input.GetAxis("Mouse X") * moveSpeed;
        float mouseY = Input.GetAxis("Mouse Y") * moveSpeed;

        transform.Translate(new Vector3(-mouseX, -mouseY, 0));
    }
    // 缩放相机
    private void ZoomCamera(float scroll)
    {
        distance -= scroll * 5f; // 调整缩放速度
        distance = Mathf.Clamp(distance, distanceMin, distanceMax); // 限制距离范围
        offset = new Vector3(0, 0, -distance);
        UpdateCameraPosition();
    }

    // 旋转相机
    private void RotateCamera()
    {
        // 获取鼠标移动量
        float mouseX = Input.GetAxis("Mouse X") * rotateSpeed;
        float mouseY = Input.GetAxis("Mouse Y") * rotateSpeed;

        // 更新偏航角和俯仰角
        yaw += mouseX;
        pitch -= mouseY; // 注意：鼠标 Y 轴移动方向与俯仰角相反
        pitch = Mathf.Clamp(pitch, pitchMinMax.x, pitchMinMax.y); // 限制俯仰角范围

        // 更新相机位置
        UpdateCameraPosition();
    }

    // 更新相机位置和朝向
    private void UpdateCameraPosition()
    {
        // 计算旋转后的偏移量
        Quaternion rotation = Quaternion.Euler(pitch, yaw, 0);
        Vector3 rotatedOffset = rotation * offset;

        // 更新相机位置
        transform.position = targetPos + rotatedOffset;

        // 相机始终朝向目标点
        transform.LookAt(targetPos);
    }
}