using UnityEngine;
using System.Collections;
using UnityEngine.EventSystems;
using System.Collections.Generic;
public class CameraController :MonoBehaviour
{
    public bool m_isScale = true;
    #region fpp
    /// <summary>
    /// 转到第一人称视角
    /// </summary>
    public bool m_fpp;
    /// <summary>
    /// 第一人称视角偏差
    /// </summary>
    public Vector3 m_fppOffset;
    /// <summary>
    /// 跟随老师
    /// </summary>
    public bool FollowTeacher;
    private bool m_followTeacher;
    #endregion

    public Transform Target;
    public float distance = 8.0f;
    public float xSpeed = 70.0f;
    public float ySpeed = 50.0f;

    public float yMinLimit = 0f;
    public float yMaxLimit = 90f;

    public float distanceMin = 8f;
    public float distanceMax = 15f;
    public float zoomSpeed = 0.5f;


    private float x = 0.0f;
    private float y = 0.0f;

    private float fx = 0f;
    private float fy = 0f;
    private float fDistance = 0;


    int m_fingerId = -1; //  当摇杆移动，控制镜头的手指
    bool m_isClickUi = false;
    Dictionary<int, bool> m_dicTouch = new Dictionary<int, bool>(); //key 为fingerid ，value为是否接触到UI
    Transform m_trans;
    float t = 0.2f;
    public float m_minDis = 1.0f;
    public bool m_isNear = false;

    [Header("God Mode")]
    public bool God; //上帝模式
    public float GodSpeed = 10;
    public float Sprint = 1.5f;
    public Vector3 MinClamp = new Vector3(0,12,0);
    public Vector3 MaxClamp = new Vector3(160,20,160);
    public Vector2 RollClamp = new Vector2(-45, 90);

    public Rigidbody _rigidbody;

    // Use this for initialization
    void Start()
    {
        _rigidbody = GetComponent<Rigidbody>();

        m_trans = this.transform;
        Vector3 angles = transform.eulerAngles;
        x = angles.y;
        y = angles.x;
        fx = x;
        fy = y;

        UpdateRotaAndPos();
        fDistance = distance;
    }

    void Update()
    {

        if (Input.touchCount == 0)//当前没有手指,全部初始化
        {
            m_fingerId = -1;
            m_dicTouch.Clear();
        }


        if (Input.touchCount == 1)
        {
            List<int> deleteFinger = new List<int>();
            foreach (var item in m_dicTouch)
            {
                if (item.Key != Input.GetTouch(0).fingerId)
                {
                    deleteFinger.Add(item.Key);
                }
            }

            //删除m_dicTouch非当前单指的item项目--》得到结果就是m_dicTouch只有当前单指或者啥也没有
            for (int i = 0; i < deleteFinger.Count; i++)
            {
                //Debug.Log("单指：删除：" + deleteFinger[i]);
                m_dicTouch.Remove(deleteFinger[i]);
            }

            switch (Input.GetTouch(0).phase)
            {
                case TouchPhase.Began:
                    if (EventSystem.current.IsPointerOverGameObject(Input.GetTouch(0).fingerId))
                    {
                        //Debug.Log("单指：增加true：" + Input.GetTouch(0).fingerId);
                        m_dicTouch[Input.GetTouch(0).fingerId] = true; //如果按在ui上为true
                    }
                    else
                    {
                        //Debug.Log("单指：增加false：" + Input.GetTouch(0).fingerId);
                        m_dicTouch[Input.GetTouch(0).fingerId] = false;
                    }


                    break;
                case TouchPhase.Moved:

                    break;
                case TouchPhase.Stationary:
                    break;
                case TouchPhase.Ended:
                    break;
                case TouchPhase.Canceled:
                    break;
                default:
                    break;
            }

        }

        if (Input.touchCount == 2)
        {
            List<int> deleteFinger = new List<int>();

            foreach (var item in m_dicTouch)
            {
                bool isDelete = true;
                for (int i = 0; i < Input.touchCount; i++)
                {
                    if (item.Key == Input.touches[i].fingerId)
                    {
                        isDelete = false;
                        break;
                    }
                }
                if (isDelete == true)
                {
                    deleteFinger.Add(item.Key);
                }
            }

            //删除m_dicTouch里面非现在按下的两个手指--》得到的结果：m_dicTouch里有一个现在按下手指中的0-2个
            for (int i = 0; i < deleteFinger.Count; i++)
            {
                //Debug.Log("双指：删除：" + deleteFinger[i]);
                m_dicTouch.Remove(deleteFinger[i]);
            }

            for (int i = 0; i < Input.touchCount; i++)
            {
                switch (Input.touches[i].phase)
                {
                    case TouchPhase.Began:
                        if (EventSystem.current.IsPointerOverGameObject(Input.touches[i].fingerId))
                        {
                            //Debug.Log("双指：增加true：" + Input.touches[i].fingerId);
                            m_dicTouch[Input.touches[i].fingerId] = true;

                        }
                        else
                        {
                            //Debug.Log("双指：增加false：" + Input.touches[i].fingerId);
                            m_dicTouch[Input.touches[i].fingerId] = false;
                        }
                        break;
                    case TouchPhase.Moved:
                        break;
                    case TouchPhase.Stationary:
                        break;
                    case TouchPhase.Ended:
                        break;
                    case TouchPhase.Canceled:
                        break;
                    default:
                        break;
                }
            }

            if (IsCanScale() == true && m_isScale == true)
            {
                Touch touchZero = Input.GetTouch(0);
                Touch touchOne = Input.GetTouch(1);

                // 上一帧每个点位置
                Vector2 touchZeroPrevPos = touchZero.position - touchZero.deltaPosition;
                Vector2 touchOnePrevPos = touchOne.position - touchOne.deltaPosition;

                //上一帧两点距离的平方，不要做平方根运算，消耗大
                float prevTouchDeltaMag = (touchZeroPrevPos - touchOnePrevPos).magnitude;
                //这一帧两点距离的平方
                float touchDeltaMag = (touchZero.position - touchOne.position).magnitude;

                // Find the difference in the distances between each frame.
                float deltaMagnitudeDiff = prevTouchDeltaMag - touchDeltaMag;
                fDistance = Mathf.Clamp(distance + deltaMagnitudeDiff * zoomSpeed, distanceMin, distanceMax);
            }

        }

        if (Application.isMobilePlatform == false && m_isScale == true)
        {
            if (Input.GetAxis("Mouse ScrollWheel") > 0)
            {
                fDistance = Mathf.Clamp(distance - zoomSpeed, distanceMin, distanceMax);
            }
            else if (Input.GetAxis("Mouse ScrollWheel") < 0)
            {
                fDistance = Mathf.Clamp(distance + zoomSpeed, distanceMin, distanceMax);
            }
        }

        distance = Mathf.Lerp(distance, fDistance, 0.25f);
    }

    private void FixedUpdate()
    {
        Move();
    }

    private void Move()
    {
        if (Application.isMobilePlatform)
        {
            if (/*Input.GetMouseButton(1) &&*/ IsCanRotate())
            {
                Touch input = new Touch();
                for (int i = 0; i < Input.touchCount; i++)
                {
                    if (Input.touches[i].fingerId == m_fingerId)
                    {
                        input = Input.touches[i];//找到控制镜头移动的手指
                    }
                }
                if (God) {
                    if (Target)
                    {
                        if (Input.touchCount > 0 && input.phase == TouchPhase.Moved)
                        {
                            float dx = input.deltaPosition.x;
                            float dy = input.deltaPosition.y;

                            x -= dx * xSpeed * Time.deltaTime;
                            y += dy * ySpeed * Time.deltaTime;
                            y = ClampAngle(y, RollClamp.x, RollClamp.y);
                        }
                    }
                }
                else {
                    if (Input.touchCount > 0 && input.phase == TouchPhase.Moved)
                    {
                        float dx = input.deltaPosition.x;
                        float dy = input.deltaPosition.y;

                        x -= dx * xSpeed * Time.deltaTime;
                        y += dy * ySpeed * Time.deltaTime;
                        y = ClampAngle(y, yMinLimit, yMaxLimit);
                    }
                }
            }
        }
        else
        {
            if (Input.GetMouseButtonDown(1))
            {
                if (EventSystem.current.IsPointerOverGameObject())
                {
                    m_isClickUi = true;
                }
            }

            if (Input.GetMouseButtonUp(0))
            {
                m_isClickUi = false;
            }
            if (m_isClickUi == false && Input.GetMouseButton(1))
            {
                if (God)
                {
                    if (Target)
                    {
                        float dx = Input.GetAxis("Mouse X");
                        float dy = Input.GetAxis("Mouse Y");

                        x += dx * xSpeed * 20 * Time.deltaTime;//*distance
                        y -= dy * ySpeed * 20 * Time.deltaTime;

                        y = ClampAngle(y, RollClamp.x, RollClamp.y);
                    }
                }
                else
                {
                    float dx = Input.GetAxis("Mouse X");
                    float dy = Input.GetAxis("Mouse Y");

                    x += dx * xSpeed * 20 * Time.deltaTime;//*distance
                    y -= dy * ySpeed * 20 * Time.deltaTime;

                    y = ClampAngle(y, yMinLimit, yMaxLimit);
                }
            }
        }

        fx = Mathf.Lerp(fx, x, 0.2f);
        fy = Mathf.Lerp(fy, y, 0.2f);

        UpdateRotaAndPos();
    }

    void UpdateRotaAndPos()
    {
        if (God)
        {
            float godspeed = (UtilitiesInput.Sprint ? GodSpeed * Sprint : GodSpeed) * Time.deltaTime;
            //transform.Translate(Vector3.forward * UtilitiesInput.Vertical * godspeed, Space.Self);
            //transform.Translate(Vector3.right * UtilitiesInput.Horizontal * godspeed, Space.Self);

            Vector3 dir = transform.forward * UtilitiesInput.Vertical + transform.right * UtilitiesInput.Horizontal;
            GodMoveCamera(dir, godspeed);

            if (UtilitiesInput.Down) transform.Translate(Vector3.down * godspeed, Space.World);
            if (UtilitiesInput.Up) transform.Translate(Vector3.up * godspeed, Space.World);

            Vector3 trans = transform.position;
            transform.position = new Vector3(Mathf.Clamp(trans.x, MinClamp.x, MaxClamp.x), Mathf.Clamp(trans.y, MinClamp.y, MaxClamp.y), Mathf.Clamp(trans.z, MinClamp.z, MaxClamp.z));


            Quaternion rotation = Quaternion.Euler(fy, fx, 0);
            Vector3 negDistance = new Vector3(0.0f, 0.0f, -distance);
            Vector3 position = rotation * negDistance + Target.position; //摄像头的位置为 移动后角度*距离 + 目标位置
            transform.rotation = rotation;
        }
        else
        {
            if (Target)
            {
                bool isCurHit = false;
                Quaternion rotation = Quaternion.Euler(fy, fx, 0);
                Vector3 negDistance = new Vector3(0.0f, 0.0f, -distance);
                Vector3 position = rotation * negDistance + Target.position; //摄像头的位置为 移动后角度*距离 + 目标位置

                Vector3 canSetPos = position;

                //m_trans.position = position;

                //Debug.DrawLine(target.position, m_trans.position, Color.red);
                //主角朝着这个方向发射射线
                RaycastHit hit;


                if (Physics.Linecast(Target.position, position, out hit))
                {
                    //Debug.Log("摄像机碰到:" + hit.collider.gameObject);

                    bool adjust = true;

                    Renderer renderer = hit.transform.GetComponent<Renderer>();
                    if (renderer == null) adjust = false;
                    if (renderer != null && !renderer.enabled) adjust = false;

                    if (adjust)
                    {
                        //当碰撞的不是摄像机也不是地形 那么直接移动摄像机的坐标
                        Vector3 posHit = hit.point;
                        Vector3 dir = posHit - Target.position;
                        //Vector3 posEnd = posHit - dir * 0.5f;
                        canSetPos = posHit - dir * 0.5f;
                        isCurHit = true;
                        //m_trans.position = posEnd;
                        //m_trans.position = position;  
                    }
                }

                //摄像机与地面的检测，不要穿过地
                if (canSetPos.y < Target.parent.position.y)
                {
                    //Debug.Log("摄像机碰到了地");
                    canSetPos.y = Target.parent.position.y;

                    Vector3 relativePos = Target.position - canSetPos;
                    rotation = Quaternion.LookRotation(relativePos);
                    isCurHit = true;
                }

                //float oldDis = (m_trans.position - target.position).sqrMagnitude;
                //float newDis = (canSetPos - target.position).sqrMagnitude;
                //if ((isCurHit == false && m_isLastHit == false) || (isCurHit == true && m_isLastHit == false) || (isCurHit == true && m_isLastHit == true)) //拉进是突进
                //{
                //    m_trans.position = canSetPos;
                //}
                //else if (m_isLastHit == true && isCurHit == false)
                //{
                //    Debug.Log("镜头远离墙体");
                //    Vector3 mainCamPos = m_trans.position;
                //    Vector3 newPos = Vector3.Lerp(mainCamPos, canSetPos, getCurrentDeltaTime() * movementLerpSpeed);
                //    m_trans.position = newPos;
                //}

                m_trans.position = m_fpp ? Target.position + m_fppOffset : canSetPos;
                m_trans.rotation = rotation;
            }
        }
    }

    public virtual void GodMoveCamera(Vector3 _direction,float speed)
    {
        if (!God) return;

        _direction.y = 0;
        _direction.x = Mathf.Clamp(_direction.x, -1f, 1f);
        _direction.z = Mathf.Clamp(_direction.z, -1f, 1f);
        // limit the input
        if (_direction.magnitude > 1f)
            _direction.Normalize();

        Vector3 targetPosition = _rigidbody.position + _direction * speed;
        Vector3 targetVelocity = (targetPosition - transform.position) / Time.deltaTime;

        bool useVerticalVelocity = true;
        if (useVerticalVelocity) targetVelocity.y = _rigidbody.velocity.y;
        _rigidbody.velocity = targetVelocity;
    }

    public static float ClampAngle(float angle, float min, float max)
    {
        if (angle < -360F)
            angle += 360F;
        if (angle > 360F)
            angle -= 360F;
        return Mathf.Clamp(angle, min, max);
    }

    /// <summary>
    /// 是否可以旋转
    /// </summary>
    /// <returns></returns>
    bool IsCanRotate()
    {
        bool ret = false;
        if (m_dicTouch.Count == 1) //只有一个手指按下，并且没按在UI上
        {
            foreach (var item in m_dicTouch)
            {
                if (item.Value == false)
                {
                    ret = true;
                    m_fingerId = item.Key;
                }
            }
        }
        else
        {
            //当有两个手指按下，一个手指在UI（包含在UI摇杆）上，一个手指没在，可以移动镜头
            int inUI = 0;
            int outUI = 0;
            foreach (var item in m_dicTouch)
            {
                if (item.Value == true)
                {
                    inUI++;
                }
                else
                {
                    outUI++;
                    m_fingerId = item.Key;
                }
            }
            if (inUI == 1 && outUI == 1)
            {
                ret = true;
            }
        }

        return ret;
    }

    //何时才能双指控制缩放-->两个手指都没按在UI上
    bool IsCanScale()
    {
        bool ret = true;
        if (m_dicTouch.Count == 2)
        {
            foreach (var item in m_dicTouch)
            {
                if (item.Value == true)
                {
                    ret = false;
                    break;
                }
            }
        }
        return ret;
    }
}