using DG.Tweening;
using SC.XR.Unity.Module_InputSystem;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
using SC.XR.Unity;
using XRTool.Util;

public class MenuUI : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
{
    Transform _pointParent;//曲线控制点父物体
    List<Transform> _anchorPointGroup = new List<Transform>();//曲线控制点集合
    Transform _menuParent;//菜单元素父物体
    List<Transform> _menuElementGroup = new List<Transform>();//菜单元素集合
    List<MenuIcon> _elementDataGroup = new List<MenuIcon>();//元素数据集合。菜单元素集合与元素数据集合始终保持一 一对应的关系（在集合中的位置）
    int _preMidIndex;//元素集合中间索引的上一个索引
    int _middleIndex;//元素集合中间索引
    int _nextMidIndex;//元素集合中间索引的下一个索引

    int _segmentNum;//所需贝塞尔曲线点连接的段数（点的数量减一）
    public Dictionary<int, Vector3> _bezierPointGroup = new Dictionary<int, Vector3>();//记录所需贝塞尔曲线定位点的集合

    Vector3[] _velocityGroup;//从一点到另一点的最大速度集合
    float _spacingTime = 0.2f;//从一点到另一点的最短时间（用于计算预设的最大速度）

    bool _isInLeft = false;//图标是否开始真正往左串位
    bool _isInRight = false;//图标是否开始真正往右串位

    float _maxDragValue = 100f;//拖动时，x坐标的预设增量基数

    Vector3 _normalScale;//正常的缩放值
    Vector3 _targetScale;//预设的目标放大值
    float _scaleFactor = 1.4f;//缩放系数

    bool _isOver = false;//链表中数据是否读取完
    bool _isClickDel = false;//是否点击了删除按钮
    bool _isInit = false;//是否初始化完毕


    /// <summary>
    /// 初始化
    /// </summary>
    public void Init()
    {
        _pointParent = transform.Find("AnchorPoint");
        _menuParent = transform.Find("Element");
        LoadAnchorPoint();
        LoadGameObject();
        _segmentNum = _menuElementGroup.Count + 1;
        _velocityGroup = new Vector3[_segmentNum];
        _normalScale = _menuElementGroup[0].localScale;
        _targetScale = _normalScale * _scaleFactor;

        SaveCurvePoint();
        GetVelocity();
        DisplayMenuElement();
        RecordValue();

        EventTool._rearrange += RearrangeElements;

        _isInit = true;
    }

    void LoadAnchorPoint()//加载定位点
    {

        foreach (Transform item in _pointParent)
        {
            _anchorPointGroup.Add(item);
        }
    }


    MenuIcon _tempIcon;
    void LoadGameObject()//加载游戏对象和游戏对象所承载的数据
    {
        foreach (Transform item in _menuParent)
        {
            _tempIcon = item.gameObject.AddComponent<MenuIcon>();
            _tempIcon.Init();

            _menuElementGroup.Add(item);
            _elementDataGroup.Add(_tempIcon);
        }

        LoadData();

        _preMidIndex = _menuElementGroup.Count / 2 - 1;
        _middleIndex = _menuElementGroup.Count / 2;
        _nextMidIndex = _menuElementGroup.Count / 2 + 1;
    }

    /// <summary>
    /// 初始化加载数据
    /// </summary>
    public void LoadData()
    {
        _isOver = false;

        //清空数据
        for (int i = 0; i < _elementDataGroup.Count; i++)
        {
            _elementDataGroup[i].DataConfig = null;
        }

        DoubleLinkNode<RoomConfig> _node = ConfigModel.Instance.GetFirstMenuItem();

        //初始化数据
        for (int i = 0; i < _elementDataGroup.Count; i++)
        {
            if (!_isOver)
            {
                if (ConfigModel.Instance.GetFirstMenuItem() != null)
                {
                    _elementDataGroup[i].DataConfig = _node;
                    _node = _node.NextNode;
                    if (_node.PreNode == ConfigModel.Instance.GetLastMenuItem())
                    {
                        _isOver = true;
                    }
                }
            }
        }
    }

    void GetVelocity()//求得从一点到另一点的最大速度(存入数组中)(速度方向从左指向右)
    {
        for (int i = 0; i < _velocityGroup.Length; i++)
        {
            float _dis = Vector3.Distance(_bezierPointGroup[i - 1], _bezierPointGroup[i]);
            _velocityGroup[i] = (_dis / _spacingTime) * (_bezierPointGroup[i] - _bezierPointGroup[i - 1]).normalized;
        }
    }

    void DisplayMenuElement()//刷新让元素处于对应的坐标点和缩放值
    {
        for (int i = 0; i < _menuElementGroup.Count; i++)
        {
            _menuElementGroup[i].localPosition = _bezierPointGroup[i];
        }

        if (!_isClickDel)//如果没有点击删除按钮，则中间位置元素为放大显示
        {
            //
            _menuElementGroup[_middleIndex].localScale = _targetScale;
            _menuElementGroup[_preMidIndex].localScale = _normalScale;
            _menuElementGroup[_nextMidIndex].localScale = _normalScale;
            //
        }
    }

    private void SaveCurvePoint()//存储贝塞尔曲线上的七个定位点位置
    {
        for (int i = -1; i < _segmentNum; i++)
        {
            float t = (i + 1) / (float)_segmentNum;
            int nodeIndex = 0;
            Vector3 pixel = CalculateBezierPoint(t, _anchorPointGroup[nodeIndex].localPosition,
                _anchorPointGroup[nodeIndex + 1].localPosition, _anchorPointGroup[nodeIndex + 2].localPosition);
            _bezierPointGroup.Add(i, pixel);
        }
    }

    void ResetCurvePoint()//重置贝塞尔曲线上的七个定位点
    {
        for (int i = -1; i < _segmentNum; i++)
        {
            float t = (i + 1) / (float)_segmentNum;
            int nodeIndex = 0;
            Vector3 pixel = CalculateBezierPoint(t, _anchorPointGroup[nodeIndex].localPosition,
                _anchorPointGroup[nodeIndex + 1].localPosition, _anchorPointGroup[nodeIndex + 2].localPosition);
            _bezierPointGroup[i] = pixel;
        }
    }


    void Update()
    {
        if (_isInit)
        {
            ResetCurvePoint();
        }

    }


    private Vector3 CalculateBezierPoint(float t, Vector3 p0, Vector3 p1, Vector3 p2)//根据t值计算相应曲线上的点
    {
        float u = 1 - t;
        float tt = t * t;
        float uu = u * u;

        Vector3 p = uu * p0;
        p += 2 * u * t * p1;
        p += tt * p2;
        return p;
    }


    public void OnBeginDrag(PointerEventData eventData)
    {
        IsDrag(true);
    }

    public void OnDrag(PointerEventData eventData)
    {
        float _delta = eventData.delta.x / _maxDragValue;//记录拖动的增量比值（用作速度比值）

        if (_delta < -0.1f)//向左拖动时
        {
            _isInRight = false;

            if (!_isInLeft)//如果没有归位到当前元素应该处于的位置上，就先让元素先移动到对应的位置上
            {
                if (_menuElementGroup[0].localPosition == _bezierPointGroup[0])
                {

                    if (!_isClickDel)//如果没有点击删除按钮，则播中间位置元素为放大显示
                    {
                        //
                        _menuElementGroup[_middleIndex].localScale = _targetScale;
                        _menuElementGroup[_preMidIndex].localScale = _normalScale;
                        //
                    }

                    _isInLeft = true;
                    return;
                }

                for (int i = 0; i < _menuElementGroup.Count; i++)
                {

                    if (!_isClickDel)//如果没有点击删除按钮，则播放缩放动画
                    {
                        //
                        if (i == _middleIndex)
                        {
                            float _prop = Vector3.Distance(_menuElementGroup[i].localPosition, _bezierPointGroup[i + 1]) /
                                Vector3.Distance(_bezierPointGroup[i], _bezierPointGroup[i + 1]);
                            _menuElementGroup[i].localScale = Vector3.Lerp(_normalScale, _targetScale, _prop);
                        }
                        else if (i == _preMidIndex)
                        {
                            float _prop = Vector3.Distance(_menuElementGroup[i].localPosition, _bezierPointGroup[i + 1]) /
                                Vector3.Distance(_bezierPointGroup[i], _bezierPointGroup[i + 1]);
                            _menuElementGroup[i].localScale = Vector3.Lerp(_targetScale, _normalScale, _prop);
                        }
                        //
                    }

                    _menuElementGroup[i].DOKill();
                    //拖拽的增量比值乘以预设的最大速度，实现设备拖拽速度与游戏对象移动速度成正比
                    _menuElementGroup[i].DOLocalMove(_bezierPointGroup[i], -_delta * _velocityGroup[i + 1].magnitude).SetSpeedBased();
                }

            }
            else//开始移位
            {
                for (int i = 0; i < _menuElementGroup.Count; i++)
                {

                    if (!_isClickDel)//如果没有点击删除按钮，则播放缩放动画
                    {
                        //
                        if (i == _middleIndex)
                        {
                            float _prop = Vector3.Distance(_menuElementGroup[i].localPosition, _bezierPointGroup[i]) /
                                Vector3.Distance(_bezierPointGroup[i], _bezierPointGroup[i - 1]);
                            _menuElementGroup[i].localScale = Vector3.Lerp(_targetScale, _normalScale, _prop);
                        }
                        else if (i == _nextMidIndex)
                        {
                            float _prop = Vector3.Distance(_menuElementGroup[i].localPosition, _bezierPointGroup[i]) /
                                Vector3.Distance(_bezierPointGroup[i], _bezierPointGroup[i - 1]);
                            _menuElementGroup[i].localScale = Vector3.Lerp(_normalScale, _targetScale, _prop);
                        }
                        //
                    }

                    _menuElementGroup[i].DOKill();
                    _menuElementGroup[i].DOLocalMove(_bezierPointGroup[i - 1], -_delta * _velocityGroup[i].magnitude).SetSpeedBased();

                }

                if (_menuElementGroup[0].localPosition == _bezierPointGroup[-1])
                {

                    _menuElementGroup[0].DOKill();
                    ShiftToLeft();
                    DisplayMenuElement();
                }
            }
        }

        else if (_delta > 0.1f)//向右拖动时
        {
            _isInLeft = false;

            if (!_isInRight)//如果没有归位到当前元素应该处于的位置上，就先让元素移动到对应的位置上
            {
                if (_menuElementGroup[0].localPosition == _bezierPointGroup[0])
                {

                    if (!_isClickDel)//如果没有点击删除按钮，则中间位置元素为放大显示
                    {
                        //
                        _menuElementGroup[_middleIndex].localScale = _targetScale;
                        _menuElementGroup[_nextMidIndex].localScale = _normalScale;
                        //
                    }

                    _isInRight = true;

                    return;
                }
                for (int i = 0; i < _menuElementGroup.Count; i++)
                {

                    if (!_isClickDel)//如果没有点击删除按钮，则播放缩放动画
                    {
                        //
                        if (i == _middleIndex)
                        {
                            float _prop = Vector3.Distance(_menuElementGroup[i].localPosition, _bezierPointGroup[i - 1]) /
                                Vector3.Distance(_bezierPointGroup[i], _bezierPointGroup[i - 1]);
                            _menuElementGroup[i].localScale = Vector3.Lerp(_normalScale, _targetScale, _prop);
                        }
                        else if (i == _nextMidIndex)
                        {
                            float _prop = Vector3.Distance(_menuElementGroup[i].localPosition, _bezierPointGroup[i - 1]) /
                                Vector3.Distance(_bezierPointGroup[i], _bezierPointGroup[i - 1]);
                            _menuElementGroup[i].localScale = Vector3.Lerp(_targetScale, _normalScale, _prop);
                        }
                        //
                    }

                    _menuElementGroup[i].DOKill();
                    _menuElementGroup[i].DOLocalMove(_bezierPointGroup[i], _delta * _velocityGroup[i].magnitude).SetSpeedBased();
                }

            }

            else//开始移位
            {
                for (int i = 0; i < _menuElementGroup.Count; i++)
                {

                    if (!_isClickDel)//如果没有点击删除按钮，则播放缩放动画
                    {
                        //
                        if (i == _middleIndex)
                        {
                            float _prop = Vector3.Distance(_menuElementGroup[i].localPosition, _bezierPointGroup[i]) /
                                Vector3.Distance(_bezierPointGroup[i], _bezierPointGroup[i + 1]);
                            _menuElementGroup[i].localScale = Vector3.Lerp(_targetScale, _normalScale, _prop);
                        }
                        else if (i == _preMidIndex)
                        {
                            float _prop = Vector3.Distance(_menuElementGroup[i].localPosition, _bezierPointGroup[i]) /
                                Vector3.Distance(_bezierPointGroup[i], _bezierPointGroup[i + 1]);
                            _menuElementGroup[i].localScale = Vector3.Lerp(_normalScale, _targetScale, _prop);
                        }
                        //
                    }

                    _menuElementGroup[i].DOKill();
                    _menuElementGroup[i].DOLocalMove(_bezierPointGroup[i + 1], _delta * _velocityGroup[i + 1].magnitude).SetSpeedBased();
                }

                if (_menuElementGroup[_menuElementGroup.Count - 1].localPosition == _bezierPointGroup[_menuElementGroup.Count])
                {

                    _menuElementGroup[_menuElementGroup.Count - 1].DOKill();
                    ShiftToRight();
                    DisplayMenuElement();
                }
            }
        }

        else//无位置变换时间超过一秒，则游戏对象不会移动
        {
            for (int i = 0; i < _menuElementGroup.Count; i++)
            {
                _menuElementGroup[i].DOKill();
            }
        }
    }

    public void OnEndDrag(PointerEventData eventData)
    {
        //拖拽结束时，移动回当前对应的定位点位置
        for (int i = 0; i < _menuElementGroup.Count; i++)
        {
            _menuElementGroup[i].DOKill();
            _menuElementGroup[i].DOLocalMove(_bezierPointGroup[i], 0.5f);

            if (!_isClickDel)//如果没有点击删除按钮，则播放缩放动画
            {
                _menuElementGroup[_middleIndex].DOScale(_targetScale, 0.5f);
            }
            else
            {
                _menuElementGroup[_middleIndex].DOScale(_normalScale, 0.5f);
            }

            _menuElementGroup[_preMidIndex].DOScale(_normalScale, 0.5f);
            _menuElementGroup[_nextMidIndex].DOScale(_normalScale, 0.5f);
        }

        IsDrag(false);
    }


    private void ShiftToLeft()//集合元素（游戏对象与数据）往左串位
    {
        //游戏对象往左串位
        var _tran = _menuElementGroup[0];
        _menuElementGroup.RemoveAt(0);
        _menuElementGroup.Add(_tran);


        //数据脚本往左串位
        var _icon = _elementDataGroup[0];
        if (_elementDataGroup[0].DataConfig != null && _elementDataGroup[_elementDataGroup.Count - 1].DataConfig != null)
        {
            _icon.DataConfig = _elementDataGroup[_elementDataGroup.Count - 1].DataConfig.NextNode;
        }
        _elementDataGroup.RemoveAt(0);
        _elementDataGroup.Add(_icon);
        _icon.RefreshData();

        //刷新记录物体的缩放值和索引值
        RecordValue();

    }

    private void ShiftToRight()//集合元素（游戏对象与数据）往右串位
    {
        //游戏对象往右串位
        var _tran = _menuElementGroup[_menuElementGroup.Count - 1];
        _menuElementGroup.RemoveAt(_menuElementGroup.Count - 1);
        _menuElementGroup.Insert(0, _tran);


        //数据脚本往右串位
        var _icon = _elementDataGroup[_elementDataGroup.Count - 1];
        if (_elementDataGroup[0].DataConfig != null && _elementDataGroup[_elementDataGroup.Count - 1].DataConfig != null)
        {
            _icon.DataConfig = _elementDataGroup[0].DataConfig.PreNode;
        }
        _elementDataGroup.RemoveAt(_elementDataGroup.Count - 1);
        _elementDataGroup.Insert(0, _icon);
        _icon.RefreshData();

        //刷新记录物体的缩放值和索引值
        RecordValue();
    }


    void RearrangeElements(Transform tran)// 回调方法：当删除完元素时，后续元素所在的游戏对象和数据往前移位
    {
        int index = -1;
        for (int i = 0; i < _menuElementGroup.Count; i++)//求出删除元素所在的位置
        {
            if (_menuElementGroup[i] == tran)
            {
                index = i;
                break;
            }
        }


        //所删除元素的游戏对象位置变换到最后一个定位点（等待向前移位）
        var _tempElement = _menuElementGroup[index];
        _tempElement.position = _bezierPointGroup[_menuElementGroup.Count];
        _menuElementGroup.RemoveAt(index);
        _menuElementGroup.Add(_tempElement);


        //游戏数据向前移位，赋予给所删除的游戏对象
        var _tempData = _elementDataGroup[index];
        _elementDataGroup.RemoveAt(index);
        _elementDataGroup.Add(_tempData);

        if (_elementDataGroup[_elementDataGroup.Count - 2].DataConfig.NextNode != ConfigModel.Instance.GetFirstMenuItem())
        {
            _elementDataGroup[_elementDataGroup.Count - 1].DataConfig = _elementDataGroup[_elementDataGroup.Count - 2].DataConfig.NextNode;
        }
        else
        {
            Debug.LogError("这个节点的下一个节点元素为头节点，出错了！");
        }


        //游戏对象向前移位
        for (int i = index; i < _menuElementGroup.Count; i++)
        {
            _menuElementGroup[i].DOLocalMove(_bezierPointGroup[i], 0.2f);
            if (i == _preMidIndex)
            {
                _menuElementGroup[_preMidIndex].DOScale(_normalScale, 0.2f);
                _menuElementGroup[_middleIndex].DOScale(_targetScale, 0.2f);
            }
            else if (i == _middleIndex)
            {
                _menuElementGroup[_middleIndex].DOScale(_targetScale, 0.2f);
                _menuElementGroup[_menuElementGroup.Count - 1].localScale = _normalScale;
            }
        }

        //刷新记录物体的缩放值和索引值
        RecordValue();
    }


    /// <summary>
    /// 刷新记录物体的缩放值和索引值
    /// </summary>
    void RecordValue()
    {
        for (int i = 0; i < _elementDataGroup.Count; i++)
        {
            _elementDataGroup[i].RoomIndex = i;
            if (i == _middleIndex)
            {
                _elementDataGroup[i].initAV3 = _targetScale;
            }
            else
            {
                _elementDataGroup[i].initAV3 = _normalScale;
            }
        }
    }


    /// <summary>
    /// 显示房间游戏对象动画
    /// </summary>
    public void ShowItemEffect()
    {
        for (int i = 0; i < _elementDataGroup.Count; i++)
        {
            _elementDataGroup[i].ShowItem();
        }
    }

    /// <summary>
    /// 隐藏房间游戏对象动画
    /// </summary>
    public void HideItemEffect()
    {
        for (int i = 0; i < _elementDataGroup.Count; i++)
        {
            _elementDataGroup[i].HideItem();
        }
    }

    /// <summary>
    /// 刷新删除按钮的显示状态
    /// </summary>
    public void RefreshDteBtn()
    {
        for (int i = 0; i < _elementDataGroup.Count; i++)
        {
            _elementDataGroup[i].ChangeDteBtn();
        }
    }

    /// <summary>
    /// 当加入房间失败时，取消事件监听
    /// </summary>
    public void RefeshisClick()
    {
        for (int i = 0; i < _elementDataGroup.Count; i++)
        {
            _elementDataGroup[i].Refeshbool();
        }
    }


    /// <summary>
    /// 刷新数据
    /// </summary>
    public void UpdateData()
    {
        for (int i = 0; i < _elementDataGroup.Count; i++)
        {
            _elementDataGroup[i].RefreshData();
        }
    }

    /// <summary>
    /// 游戏对象是否处于拖拽状态
    /// </summary>
    /// <param name="isDrag"></param>
    private void IsDrag(bool isDrag)
    {
        for (int i = 0; i < _elementDataGroup.Count; i++)
        {
            _elementDataGroup[i]._isDrag = isDrag;
        }
    }


    void OnDestroy()
    {
        EventTool._rearrange -= RearrangeElements;
    }
}