using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
using ZXK.BYSS;
/********************************************************************************
*Create By CG
*Function 摄像机自身控制控制
*WSAD:前后左右-QE:上下-鼠标滚轮:镜头远近-按住鼠标右键,拖动鼠标:摄像机上下左右旋转
*********************************************************************************/
namespace ZXK.UTility
{
    public class CameraControl : MonoBehaviour
    {
        public float _RotSpeed = 256;
        public float _MoveSpeed = 10;
        public float _ZoomSpeed = 30;
        
        //摄像机三维位移受限，暂时实现上下受限
        private Vector3 _minPos = new Vector3(-15.0f, 0.3f, -23.0f);
        private Vector3 _maxPos = new Vector3(15.0f, 6.0f, 23.0f);
        private float _minZoom = 5.0f;
        private float _maxZoom = 100f;


        private Vector3 _translation;
        private float rotX = 0.0f;
        private float rotY = 0.0f;


        private void OnEnable()
        {
            Vector3 angles = transform.eulerAngles;
            rotX = angles.y;
            rotY = angles.x;
        }
        private void Update()
        {
            if (!EventSystem.current.IsPointerOverGameObject())
            {
                _translation = GetInputTranslationDirection();

                SetCamDistance();
                SetCamPostion();
                SetCamRotation();
            }
        }
        /// <summary>
        /// 设置摄像机镜头远近
        /// </summary>
        private void SetCamDistance()
        {
            //transform.localPosition += transform.forward * Input.mouseScrollDelta.y * Time.deltaTime * _ZoomSpeed;
            float zoom = transform.GetComponent<Camera>().fieldOfView;
            if (zoom < _minZoom&& Input.mouseScrollDelta.y>0 || zoom > _maxZoom && Input.mouseScrollDelta.y < 0)
            {
                return;
            }
            transform.GetComponent<Camera>().fieldOfView-= Input.mouseScrollDelta.y * Time.deltaTime * _ZoomSpeed;
        }
        /// <summary>
        /// 设置摄像机位移
        /// </summary>
        private void SetCamPostion()
        {
            transform.position += _translation * Time.deltaTime * _MoveSpeed;
        }
        /// <summary>
        /// 设置摄像机旋转
        /// </summary>
        private void SetCamRotation()
        {
          
        
            if (Input.GetKey(KeyCode.Mouse1))
            {
                float mouse_x = Input.GetAxis("Mouse X");
                float mouse_y = Input.GetAxis("Mouse Y");
                rotX += mouse_x * _RotSpeed * Time.deltaTime;
                rotY -= mouse_y * _RotSpeed * Time.deltaTime;
                rotY = Mathf.Clamp(rotY, -90, 90);//防止翻跟头
            
      


                //Quaternion rotation = Quaternion.Euler(rotY, rotX, 0);//利用欧拉角防止万向锁
                //transform.rotation = rotation;
                transform.localEulerAngles = new Vector3(rotY, rotX);
            }
        }

        Vector3 GetInputTranslationDirection()
        {
            Vector3 direction = new Vector3();
            if (Input.GetKey(KeyCode.W))
            {
                //direction += Vector3.forward;
                
                if (AppManagement.Instance._CurModel == EnumCtrl.Model.Train ||
                    AppManagement.Instance._CurModel == EnumCtrl.Model.Exam)
                {
                    //不让摄像机有实际前进位移，方便拖拽出来的物体可以被看到
                    float zoom = transform.GetComponent<Camera>().fieldOfView;
                    if (zoom > _minZoom)
                    {
                        transform.GetComponent<Camera>().fieldOfView -= 1 * Time.deltaTime * _ZoomSpeed;
                    }
                }
                else
                {
                    Vector3 forward = new Vector3(transform.forward.x, 0, transform.forward.z);
                    direction += forward.normalized;
                }
            }
            if (Input.GetKey(KeyCode.S))
            {
                //direction += Vector3.back;

               
                if (AppManagement.Instance._CurModel == EnumCtrl.Model.Train ||
                    AppManagement.Instance._CurModel == EnumCtrl.Model.Exam)
                {
                    float zoom = transform.GetComponent<Camera>().fieldOfView;
                    if (zoom < _maxZoom)
                    {
                        transform.GetComponent<Camera>().fieldOfView -= -1 * Time.deltaTime * _ZoomSpeed;
                    }
                }
                else
                {
                    Vector3 forward = new Vector3(transform.forward.x, 0, transform.forward.z);
                    direction -= forward.normalized;
                }
            }
            if (Input.GetKey(KeyCode.A))
            {
                //direction += Vector3.left;
                Vector3 right = new Vector3(transform.right.x, 0, transform.right.z);
                direction -= right;
            }
            if (Input.GetKey(KeyCode.D))
            {
                //direction += Vector3.right;
                Vector3 right = new Vector3(transform.right.x, 0, transform.right.z);
                direction += right;
            }
            if (transform.position.y < _maxPos.y && Input.GetKey(KeyCode.Q))
            {
                direction += Vector3.up;
            }
            if (transform.position.y> _minPos.y && Input.GetKey(KeyCode.E))
            {
                direction += Vector3.down;
            }
            return direction;
        }
    }
}