using System.Collections;
using UnityEngine;
using UnityEngine.EventSystems;
/// <summary>
/// 摄像机围绕旋转脚本
/// </summary>
public class CameraOrbit : CameraBase
{
    [Header("开关")]
    [Tooltip("是否可控.关闭则无法控制摄像机")]
    public bool controlable = true;
    [Tooltip("观察的目标")]
    public Transform target;
    [Tooltip("摄像机与目标之间的距离")]
    public float Distance = 5f;
    [Header("限制")]
    [Tooltip("摄像机与目标之间的距离限制")]
    public Vector2 distanceClamp = new Vector2(1.5f, 5);
    public Vector2 yLimitClamp = new Vector2(-20, 80);
    public Vector2 xLimitClamp = new Vector2(360, 360);
    public Vector2 speedAxis = new Vector2(100, 100);
    [Header("控制参数")]
    [Tooltip("鼠标滚轮灵敏度")]
    [Range(1, 10)]
    public float scrollSensitivity = 5;
    [Range(1, 25)]
    public float zoomSpeed = 7;
    [Range(1, 25)]
    public float lerpSpeed = 7;
    [Range(0.1f, 15)]
    public float inputLerp = 7;
    [Range(0.001f, 0.07f)]
    public float inputMultiplier = 0.02f;
    [Tooltip("切换目标时黑屏时间")]
    [Range(0.01f, 5f)]
    public float swichtSpeed = 2;
    [Header("Movement")]
    public CameraMovementType movementType = CameraMovementType.Normal;
    public CameraMouseInputType rotateInputKey = CameraMouseInputType.MobileTouch;
    private float x, y;
    private float horizontal;
    private float vertical;
    private float lastHorizontal = 0;
    private float distance = 0;
    private Vector3 zoomVector;
    private Vector3 currentPosition;
    private Quaternion currentRotation;
    private float initXRotation;
    private bool isSwitchingTarget = false;
    private float fadeAlpha = 0;
    [SerializeField]
    private Texture2D fadeTexture = null;
    public bool Controlable
    {
        get { return controlable; }
        set { controlable = value; }
    }
    public bool CanRotate { get; set; } = true;
    private void Start()
    {
        Init();
    }
    private void LateUpdate()
    {
        if (target == null)
        {
            Debug.LogWarning("Target is not assigned to orbit camera!", this);
            return;
        }
        if (isSwitchingTarget)return;

        if (CanRotate)
        {
            ZoomControl(false);
            OrbitControl();
        }
        else
        {
            ZoomControl(true);
        }
        //if (CanRotate && !EventSystem.current.IsPointerOverGameObject())
        //{
        //    ZoomControl(false);
        //    OrbitControl();
        //}
        //else
        //{
        //    ZoomControl(true);
        //}
    }
    /// <summary>
    /// 初始化
    /// </summary>
    private void Init()
    {
        distance = Distance;
        Vector3 eulerAngles = Transform.eulerAngles;
        x = eulerAngles.y;
        y = eulerAngles.x;
        initXRotation = eulerAngles.y;
        horizontal = x;
        vertical = y;
    }
    /// <summary>
    /// 旋转控制
    /// </summary>
    private void OrbitControl()
    {
        if (controlable)
        {
            if (IsInputKeyRotate)
            {
                horizontal += (speedAxis.x * inputMultiplier) * AxisX;
                vertical -= (speedAxis.y * inputMultiplier) * AxisY;
                lastHorizontal = AxisX;
            }
        }
        float delta = Time.deltaTime;
        vertical = MathfUtils.ClampAngle(vertical, yLimitClamp.x, yLimitClamp.y);
        if (xLimitClamp.x < 360 && yLimitClamp.y < 360)
        {
            horizontal = MathfUtils.ClampAngle(horizontal, (initXRotation - xLimitClamp.y), (xLimitClamp.x + initXRotation));
        }
        x = Mathf.Lerp(x, horizontal, Time.deltaTime * inputLerp);
        y = Mathf.Lerp(y, vertical, Time.deltaTime * inputLerp);
        y = MathfUtils.ClampAngle(y, yLimitClamp.x, yLimitClamp.y);
        currentRotation = Quaternion.Euler(y, x, 0f);
        currentPosition = ((currentRotation * zoomVector)) + target.position;
        switch (movementType)
        {
            case CameraMovementType.Dynamic:
                Transform.position = Vector3.Lerp(Transform.position, currentPosition, (lerpSpeed) * delta);
                Transform.rotation = Quaternion.Lerp(Transform.rotation, currentRotation, (lerpSpeed * 2) * delta);
                break;
            case CameraMovementType.Normal:
                Transform.position = currentPosition;
                Transform.rotation = currentRotation;
                break;
            case CameraMovementType.Towars:
                Transform.position = Vector3.MoveTowards(Transform.position, currentPosition, lerpSpeed);
                Transform.rotation = Quaternion.RotateTowards(Transform.rotation, currentRotation, lerpSpeed);
                break;
        }
    }
    /// <summary>
    /// 距离控制
    /// </summary>
    /// <param name="autoApply"></param>
    private void ZoomControl(bool autoApply)
    {
        float delta = Time.deltaTime;
        distance = Mathf.Clamp(distance - (MouseScrollWheel * scrollSensitivity), distanceClamp.x, distanceClamp.y);
       // distance = (distance < 1) ? 1 : distance;
        Distance = Mathf.SmoothStep(Distance, distance, delta * zoomSpeed);
        zoomVector = new Vector3(0, 0, -Distance);
        if (autoApply)
        {
            currentPosition = (currentRotation * zoomVector) + target.position;
            switch (movementType)
            {
                case CameraMovementType.Dynamic:
                    Transform.position = Vector3.Lerp(Transform.position, currentPosition, (lerpSpeed) * delta);
                    Transform.rotation = Quaternion.Lerp(Transform.rotation, currentRotation, (lerpSpeed * 2) * delta);
                    break;
                case CameraMovementType.Normal:
                    Transform.position = currentPosition;
                    Transform.rotation = currentRotation;
                    break;
                case CameraMovementType.Towars:
                    Transform.position = Vector3.MoveTowards(Transform.position, currentPosition, lerpSpeed);
                    Transform.rotation = Quaternion.RotateTowards(Transform.rotation, currentRotation, lerpSpeed);
                    break;
            }
        }
    }
    private bool IsInputKeyRotate
    {
        get
        {
            switch (rotateInputKey)
            {
                case CameraMouseInputType.All:
                    return (Input.GetKey(KeyCode.Mouse0) || Input.GetKey(KeyCode.Mouse1) || Input.GetKey(KeyCode.Mouse2) || Input.GetMouseButton(0));
                case CameraMouseInputType.LeftAndRight:
                    return (Input.GetKey(KeyCode.Mouse0) || Input.GetKey(KeyCode.Mouse1));
                case CameraMouseInputType.LeftMouse:
                    return (Input.GetKey(KeyCode.Mouse0));
                case CameraMouseInputType.RightMouse:
                    return (Input.GetKey(KeyCode.Mouse1));
                case CameraMouseInputType.MouseScroll:
                    return (Input.GetKey(KeyCode.Mouse2));
                case CameraMouseInputType.MobileTouch:
                    return (Input.GetMouseButton(0) || Input.GetMouseButton(1));
                default:
                    return (Input.GetKey(KeyCode.Mouse0));
            }
        }
    }
    public void SetTarget(Transform newTarget)
    {
        StopCoroutine("TranslateTarget");
        StartCoroutine("TranslateTarget", newTarget);
        //target = newTarget;
    }
    IEnumerator TranslateTarget(Transform newTarget)
    {
        isSwitchingTarget = true;
        while (fadeAlpha < 1)
        {
            transform.position = Vector3.Lerp(transform.position, transform.position + new Vector3(0, 2, -2), Time.deltaTime);
            fadeAlpha += Time.smoothDeltaTime * swichtSpeed;
            yield return null;
        }
        target = newTarget;
        isSwitchingTarget = false;
        while (fadeAlpha > 0)
        {
            fadeAlpha -= Time.smoothDeltaTime * swichtSpeed;
            yield return null;
        }
    }
    public void SetViewPoint(int side)
    {
        if (side == 0)//top
        {
            vertical = 90;
            horizontal = 0;
        }
        else if (side == 1)//front
        {
            vertical = 0;
            horizontal = 0;
        }
        else if (side == 2)//right
        {
            vertical = 0;
            horizontal = -90;
        }
        else if (side == 3)//left
        {
            vertical = 0;
            horizontal = 90;
        }
        else if (side == 4)//back
        {
            vertical = 0;
            horizontal = 180;
        }
        else if (side == 5)//
        {
            vertical = 0;
            horizontal = -45;
        }
        else if (side == 6)//
        {
            vertical = 0;
            horizontal = 45;
        }
        else if (side == 7)//
        {
            vertical = 0;
            horizontal = 135;
        }
        else if (side == 8)//
        {
            vertical = 0;
            horizontal = -135;
        }
    }
    /// <summary>
    /// 
    /// </summary>
    /// <param name="value"></param>
    public void SetStaticZoom(float value)
    {
        distance += value;
    }
    /// <summary>
    /// 
    /// </summary>
    public float Horizontal
    {
        get
        {
            return horizontal;
        }
        set
        {
            horizontal += value;
            lastHorizontal = horizontal;
        }
    }

    /// <summary>
    /// 
    /// </summary>
    public float Vertical
    {
        get
        {
            return vertical;
        }
        set
        {
            vertical += value;
        }
    }
    private void OnGUI()
    {
        if (isSwitchingTarget)
        {
            GUI.color = new Color(1, 1, 1, fadeAlpha);
            if (fadeTexture != null)
                GUI.DrawTexture(new Rect(0, 0, Screen.width, Screen.height), fadeTexture, ScaleMode.StretchToFill);
            return;
        }
    }
    void OnDrawGizmosSelected()
    {
        Gizmos.color = new Color32(0, 221, 221, 255);
        if (target != null)
        {
            Gizmos.DrawLine(transform.position, target.position);
            Gizmos.matrix = Matrix4x4.TRS(target.position, transform.rotation, new Vector3(1f, 0, 1f));
            Gizmos.DrawWireSphere(target.position, Distance);
            Gizmos.matrix = Matrix4x4.identity;
        }
        Gizmos.DrawCube(transform.position, new Vector3(1, 0.2f, 0.2f));
        Gizmos.DrawCube(transform.position, Vector3.one / 2);
    }
}