using System;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
using System.Collections;

/// <summary>
/// 
/// </summary>
public class UI_ScrollFlow : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
{
    /// <summary>
    /// 元素初始化
    /// </summary>
    /// <param name="go"> 游戏对象 </param>
    /// <param name="dataIndex"> 数据索引 </param>
    public delegate void OnInitializeItem(GameObject go, int dataIndex);

    /// <summary>
    /// 元素初始化
    /// </summary>
    public OnInitializeItem onInitializeItem;

    /// <summary>
    ///  卡牌的像素宽度
    /// </summary>
    public float itemWidth = 700;

    /// <summary>
    /// 最大缩放
    /// </summary>
    public float MaxScale = 1.0f;

    /// <summary>
    /// 开始坐标值
    /// </summary>
    public float startValue = 0.5f;

    /// <summary>
    /// 
    /// </summary>
    private int defaultItemIndex = 0;

    /// <summary>
    /// 卡牌之间的间隔坐标
    /// </summary>
    private float spaceValue = 0.2f;

    /// <summary>
    /// 移动速度曲线
    /// </summary>
    public AnimationCurve SpeedCurve;

    /// <summary>
    /// 坐标曲线
    /// </summary>
    public AnimationCurve PositionCurve;

    /// <summary>
    /// 缩放幅度大小曲线
    /// </summary>
    public AnimationCurve ScaleCurve;

    /// <summary>
    /// 拖拽时候的,托主幅度量
    /// </summary>
    private float dragV = 0;

    /// <summary>
    /// 拖拽时候的,计算值
    /// </summary>
    private Vector2 start_point, add_vect;

    /// <summary>
    ///  移动结束事件
    /// </summary>
    public event CallBack<UI_ScrollFlow_Item> MoveEnd;

    /// <summary>
    /// 更改当前卡牌的状态
    /// </summary>
    public event CallBack<bool, UI_ScrollFlow_Item> EventRefreshCardState;

    /// <summary>
    /// 是否开启动画
    /// </summary>
    public bool _anim = false;

    /// <summary>
    /// 移动的量
    /// </summary>
    private float AddV = 0;

    /// <summary>
    /// 移动方向
    /// </summary>
    private float Vk = 0;

    /// <summary>
    /// 
    /// </summary>
    private float Vtotal = 0;

    /// <summary>
    /// 动画速度 * 单位时间* 移动方向,计算出来的移动值
    /// </summary>
    private float CurrentV = 0;

    /// <summary>
    /// 
    /// </summary>
    private float VT = 0;

    /// <summary>
    /// 
    /// </summary>
    private float _v1 = 0, _v2 = 0;

    /// <summary>
    /// 动画速度
    /// </summary>
    public float _anim_speed = 1f;

    /// <summary>
    /// 
    /// </summary>
    public UI_ScrollFlow_Item Current;

    /// <summary>
    /// 初始化
    /// </summary>
    /// <param name="dataCount"> 数据的数量 </param>
    public void Init(int dataCount)
    {
        // 不显示元素预制物体
        goItemPrefab.SetActive(false);


        // 如果数据数量为 0 ，没有初始化的必要
        if (dataCount <= 0)
        {
            return;
        }
        mDataCount = dataCount;

        unUseItem.Clear();
        useItemList.Clear();
         Debug.LogError("Init！！！！！" + useItemList.Count);
        setUpdateRectItem(0, true);

    }

    /// <summary>
    ///  初始化 英雄滑动列表的组件设置
    /// </summary>
    public void InitHeroComponmentsSetting()
    {
        MaxScale = 1.0f;
        itemWidth = 500;

        float[] tixxx = new float[] { -0.95f, -0.59f, -0.23f, 0.13f, 0.5f, 0.87f, 1.23f, 1.59f, 1.95f };

        Keyframe[] ks = new Keyframe[3];
        ks[0] = new Keyframe(0, 0.9f);
        ks[1] = new Keyframe(0.5f, 1.0f);
        ks[2] = new Keyframe(1.0f, 0.9f);
        ScaleCurve = new AnimationCurve(ks);

        Keyframe[] spks = new Keyframe[5];
        spks[0] = new Keyframe(-1.0f, 2.0f);
        spks[1] = new Keyframe(-0.5f, 1.5f);
        spks[2] = new Keyframe(0, 0.5f);
        spks[3] = new Keyframe(0.5f, 1.5f);
        spks[4] = new Keyframe(1.0f, 2.0f);
        SpeedCurve = new AnimationCurve(spks);

        Keyframe[] posArr = new Keyframe[tixxx.Length];
        int index = 0;
        for (int i = -4; i <= 4; i++)
        {
            posArr[index] = new Keyframe(startValue + i * spaceValue, tixxx[index]);
            index++;
        }

        PositionCurve = new AnimationCurve(posArr);
    }

    /// <summary>
    ///  初始化 图鉴滑动列表的组件设置
    /// </summary>
    public void InitBook_ComponmentsSetting()
    {
        MaxScale = 1.0f;
        itemWidth = 200;

        Keyframe[] spks = new Keyframe[5];
        spks[0] = new Keyframe(-1.0f, 1.5f);
        spks[1] = new Keyframe(-0.5f, 1);
        spks[2] = new Keyframe(0, 0.5f);
        spks[3] = new Keyframe(0.5f, 1);
        spks[4] = new Keyframe(1.0f, 1.5f);
        SpeedCurve = new AnimationCurve(spks);

        Keyframe[] ks = new Keyframe[2];
        ks[0] = new Keyframe(-1.0f, 1.0f);
        ks[1] = new Keyframe(1.0f, 1.0f);
        ScaleCurve = new AnimationCurve(ks);

        float[] tixxx = new float[] { -3.0f, -2.0f, -1.0f, 0, 1.0f, 2.0f, 3.0f };
        Keyframe[] posArr = new Keyframe[tixxx.Length];
        int index = 0;
        for (int i = -3; i <= 3; i++)
        {
            posArr[index] = new Keyframe(startValue + i * spaceValue, tixxx[index]);
            index++;
        }

        PositionCurve = new AnimationCurve(posArr);
    }

    /// <summary>
    /// 
    /// </summary>
    public void InitPvp_ComponmentsSetting()
    {
        MaxScale = 1.0f;
        itemWidth = 800;

        Keyframe[] spks = new Keyframe[5];
        spks[0] = new Keyframe(-1.0f, 1.5f);
        spks[1] = new Keyframe(-0.5f, 1);
        spks[2] = new Keyframe(0, 0.5f);
        spks[3] = new Keyframe(0.5f, 1);
        spks[4] = new Keyframe(1.0f, 1.5f);

        SpeedCurve = new AnimationCurve(spks);

        Keyframe[] ks = new Keyframe[3];
        ks[0] = new Keyframe(0, 0.9f);
        ks[1] = new Keyframe(0.5f, 1.0f);
        ks[2] = new Keyframe(1.0f, 0.9f);
        ScaleCurve = new AnimationCurve(ks);

        float[] tixxx = new float[] { -3.0f, -2.0f, -1.0f, 0, 1.0f, 2.0f, 3.0f };
        Keyframe[] posArr = new Keyframe[tixxx.Length];
        int index = 0;
        for (int i = -3; i <= 3; i++)
        {
            posArr[index] = new Keyframe(startValue + i * spaceValue, tixxx[index]);
            index++;
        }

        PositionCurve = new AnimationCurve(posArr);
    }

    /// <summary>
    /// 当前处于选中的对象数据索引
    /// </summary>
    public int CurSelectElementIndex = -1;

    /// <summary>
    ///  接手到通知,某个子对象的选中状态发生改变了
    /// </summary>
    public void OnReceiveUpdateState(bool isSelected, UI_ScrollFlow_Item item)
    {
        if (isSelected)
        {
            if (CurSelectElementIndex != item.Index)
            {
                CurSelectElementIndex = item.Index;
                RefreshDraw();
            }
        }

        if (EventRefreshCardState != null)
        {
            EventRefreshCardState(isSelected, item);
        }
    }

    /// <summary>
    /// 当前元素总值
    /// </summary>
    public int mDataCount;

    /// <summary>
    /// 上次定位的位置
    /// </summary>
    private int _lastCurIndex;
    /// <summary>
    /// 
    /// </summary>
    private int lastCurIndex
    {
        get { return _lastCurIndex; }
        set
        {
            if (_lastCurIndex != value)
            {

                _lastCurIndex = value;
            }
        }
    }

    /// <summary>
    /// 
    /// </summary>
    private int curIndex = 0; 

    /// <summary>
    /// 英雄列表滑动的数据发生变化
    /// </summary>
    public void Hero_DataChanged(int dataCount, bool bResetPos)
    {
        CurSelectElementIndex = -1;
        Current = null;

        mDataCount = dataCount;

        if (bResetPos)
        {
            //if (mDataCount > 5)
            //{
            //    defaultItemIndex = 5;
            //}
            //else
            //{
            //    defaultItemIndex = mDataCount - 1;
            //}

            //lastCurIndex = defaultItemIndex;
        }

        //// Debug.LogError("bResetPos:::" + bResetPos + " lastCurIndex:: " + lastCurIndex);
        /*
         * 如果需要重新定位的话
         * 重新计算每个数据在时间轴的位置
         */
        // 因为数据改变了，元素要重新获取数据
        for (int i = useItemList.Count - 1; i >= 0; i--)
        {
            UI_ScrollFlow_Item item = useItemList[i];

            item.Index = -1;
            useItemList.Remove(item);
            unUseItem.Enqueue(item);
        }
        //// Debug.LogError("DataChanged！！！！！" + useItemList.Count);
        setUpdateRectItem(lastCurIndex, true);

        //////if (bResetPos)
        //////{
        //////    if (useItemList.Count > 0)
        //////    {
        //////        UI_ScrollFlow_Item script = useItemList[0];
        //////        if (script == null)
        //////        {
        //////            return;
        //////        }

        //////        if (Current != script)
        //////        {
        //////            //// Debug.LogError("Current 0.5fIndex:::" + Current.Index + " script:: " + script.Index);
        //////            ToAppointedItem(script);
        //////        }
        //////    }
        //////}
        //////else
        //////{
        //////    UI_ScrollFlow_Item script = null;
        //////    //// Debug.LogError(" lastCurIndex:: " + lastCurIndex + " useItemList count:::  " + useItemList.Count);
        //////    if (useItemList.Count > 0)
        //////    {
        //////        if (lastCurIndex >= useItemList.Count)
        //////        {
        //////            script = useItemList[useItemList.Count - 1];
        //////        }
        //////        else
        //////        {
        //////            script = useItemList[lastCurIndex];
        //////        }
        //////    }

        //////    if (script != null)
        //////    {
        //////        //// Debug.LogError("0.5fIndex:::script:: " + script.Index);
        //////        ToAppointedItem(script);
        //////    }
        //////}
        if (Current != null)
        {
            ToAppointedItem(Current);
        }
        RefreshDraw();
    }
   
    /// <summary>
    /// 图鉴的数据发生变化
    /// </summary>
    public void Book_DataChanged(int dataCount)
    {
        Current = null;

        mDataCount = dataCount;
        lastCurIndex = 2;

        /*
         * 如果需要重新定位的话
         * 重新计算每个数据在时间轴的位置
         */
        // 因为数据改变了，元素要重新获取数据
        for (int i = useItemList.Count - 1; i >= 0; i--)
        {
            UI_ScrollFlow_Item item = useItemList[i];

            item.Index = -1;
            useItemList.Remove(item);
            unUseItem.Enqueue(item);
        }
   
        setUpdateRectItem(lastCurIndex, true);

        UI_ScrollFlow_Item script = null;
     
        if (useItemList.Count > 0)
        {
            if (lastCurIndex >= useItemList.Count)
            {
                script = useItemList[useItemList.Count - 1];
            }
            else
            {
                script = useItemList[lastCurIndex];
            }
        }

        if (script != null)
        {
            ToAppointedItem(script);
        }
    }
    #region  

     /// <summary>
    /// 刷新元素
    /// </summary>
    /// <param name="scrollPerLineIndex"> 当前所处的行数 </param>
    private void setUpdateRectItem(int scrollPerLineIndex, bool isNeedFindCurrent = false)
    {
        if (scrollPerLineIndex < 0)
        {
            return;
        }

        int startDataIndex = 0;
        int endDataIndex = mDataCount;

        // 移除        
        for (int i = useItemList.Count - 1; i >= 0; i--)
        {
            UI_ScrollFlow_Item item = useItemList[i];
            int index = item.Index;
            if (index < startDataIndex || index >= endDataIndex)
            {
                item.Index = -1;
                useItemList.Remove(item);
                unUseItem.Enqueue(item);
            }
        }

        // 显示
        for (int dataIndex = startDataIndex; dataIndex < endDataIndex; dataIndex++)
        {
            if (dataIndex < 0)
            {
                continue;
            }

            if (dataIndex >= mDataCount)
            {
                continue;
            }

            if (isExistDataByDataIndex(dataIndex))
            {
                //需要重置下坐标位置 
                continue;
            }

            ////StartCoroutine(createItem(dataIndex, isNeedFindCurrent));
            createItem(dataIndex, isNeedFindCurrent);
        }
    }

    private int tempStartIndex = 0;

    private int tempEndIndex = 0;

    /// <summary>
    /// content 对象
    /// </summary>
    public RectTransform nodeContent = null;

    /// <summary>
    /// 元素预制物体
    /// </summary>
    public GameObject goItemPrefab = null;

    /// <summary>
    /// 创建元素
    /// </summary>
    /// <param name="dataIndex"> 数据索引 </param>
    private void createItem(int dataIndex, bool isNeedFindCurrent)
    {
        UI_ScrollFlow_Item item = null;
        if (unUseItem.Count > 0)
        {
            item = unUseItem.Dequeue();
        }
        else
        {
            GameObject temp = addChild(goItemPrefab, nodeContent);
            item = temp.GetComponent<UI_ScrollFlow_Item>();
            if (item == null)
            {
                AssemblyHelper.Instance.BindScript("UI_ScrollFlow_Item", temp);
                item = temp.GetComponent<UI_ScrollFlow_Item>();
            }
        }
        item.gameObject.name = dataIndex.ToString();
        item.gameObject.SetActive(true);
        item.ScrollFlowParent = this;
        item.Index = dataIndex;
        useItemList.Add(item);


        float dv = startValue + (dataIndex - lastCurIndex) * spaceValue;
        //// Debug.LogError("dv ！！！！！" + dv);

        item.Drag(dv);

        if (isNeedFindCurrent)
        {
            if (Mathf.Abs(dv - startValue) < 0.05f)
            {
                Current = item;
            }
        } 

        ////yield return null;
    }

    /// <summary>
    /// 当前数据是否存在 List 中
    /// </summary>
    /// <param name="dataIndex"> 数据索引 </param>
    /// <returns> 是否已存在 </returns>
    private bool isExistDataByDataIndex(int dataIndex, bool isNeedFindCurrent = false)
    {
        if (useItemList == null || useItemList.Count <= 0)
        {
            return false;
        }

        for (int i = 0; i < useItemList.Count; i++)
        {
            if (useItemList[i].Index == dataIndex)
            {
                return true;
            }
        }

        return false;
    }

    /// <summary>
    /// 实例化预设对象 、添加实例化对象到指定的子对象下
    /// </summary>
    /// <param name="goPrefab"> 元素预制物体 </param>
    /// <param name="parent"> 父节点 </param>
    /// <returns> 新创建的元素对象 </returns>
    private GameObject addChild(GameObject goPrefab, Transform parent)
    {
        if (goPrefab == null || parent == null)
        {
             Debug.LogError("异常。UIWarpContent.cs addChild(goPrefab = null  || parent = null)");
            return null;
        }

        GameObject goChild = GameObject.Instantiate(goPrefab) as GameObject;
        goChild.transform.SetParent(parent, false);
        goChild.SetActive(true);

        return goChild;
    }

    /// <summary>
    /// 正在使用中的元素
    /// </summary>
    private List<UI_ScrollFlow_Item> useItemList = new List<UI_ScrollFlow_Item>();

    /// <summary>
    /// 未在使用中的元素
    /// </summary>
    private Queue<UI_ScrollFlow_Item> unUseItem = new Queue<UI_ScrollFlow_Item>();

    /// <summary>
    /// 销毁
    /// </summary>
    private void OnDestroy()
    {
        nodeContent = null;
        goItemPrefab = null;
        onInitializeItem = null;

        useItemList.Clear();
        unUseItem.Clear();

        useItemList = null;
        unUseItem = null;
    }
    #endregion
 
    /// <summary>
    /// 
    /// </summary>
    /// <param name="eventData"></param>
    public void OnBeginDrag(PointerEventData eventData)
    {
        start_point = eventData.position;
        add_vect = Vector3.zero;
        _anim = false;
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="eventData"></param>
    public void OnDrag(PointerEventData eventData)
    {
        //判断此时 是不是已经到列表尽头,然后做一个极限设定
        if (useItemList[0].v > startValue)
        {
            float abs = Mathf.Abs(startValue - useItemList[0].v);
            if (abs > spaceValue)
            {
                return;
            }
        }

        if (useItemList[useItemList.Count - 1].v < startValue)
        {
            float abs = Mathf.Abs(startValue - useItemList[useItemList.Count - 1].v);
            if (abs > spaceValue)
            {
                return;
            }
        }

        add_vect = eventData.position - start_point;
        dragV = eventData.delta.x * 1.00f / itemWidth;


        //计算移动量,对应卡牌的比例
        for (int i = 0; i < useItemList.Count; i++)
        {
            useItemList[i].Drag(dragV);
        }
    }

    /// <summary>
    /// 这块需要调整
    /// 要不然不知道拖拽到哪个了......................
    /// </summary>
    /// <param name="eventData"></param>
    public void OnEndDrag(PointerEventData eventData)
    {
        float k = 0, v1;

        for (int i = 0; i < useItemList.Count; i++)
        {
            if (useItemList[i].v >= startValue)
            {
                v1 = (useItemList[i].v - startValue) % spaceValue;

                if (add_vect.x >= 0)
                {
                    k = spaceValue - v1;
                    //确定向右移动 ()
                }
                else
                {
                    k = v1 * -1;
                }
                break;
            }
        }

        add_vect = Vector3.zero;

        // 判断是否拖拽到极限
        if (useItemList[0].v > startValue)
        {
            //说明向右滑道头了
            k = useItemList[0].v;
            k = startValue - k;

            AnimToEnd(k);
            return;
        }

        if (useItemList[useItemList.Count - 1].v < startValue)
        {
            k = useItemList[useItemList.Count - 1].v;
            k = startValue - k;

            AnimToEnd(k);
            return;
        }

        AnimToEnd(k);
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="v"></param>
    /// <returns></returns>
    public float GetPositionX(float v, int _index)
    {
        //return v * itemWidth;        
        return PositionCurve.Evaluate(v) * itemWidth;
    }

    /// <summary>
    /// 获取卡牌移动速度
    /// </summary>
    /// <param name="v"></param>    
    /// <returns></returns>
    public float GetMoveSpeed(float v)
    {
        //return v * itemWidth;        
        return SpeedCurve.Evaluate(v) * 1.0f;
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="v"></param>
    /// <returns></returns>
    public float GetScale(float v)
    {
        return ScaleCurve.Evaluate(v) * MaxScale;
    }

    /// <summary>
    /// 主要进行排序
    /// 除了中间之外的, 左侧的,从左到右绘制.
    /// 中间右侧,从右到左绘制
    /// </summary>
    public void LateUpdate()
    {
        if (!IsOPenReDraw)
        {
            return;
        }

        List<UI_ScrollFlow_Item> left = new List<UI_ScrollFlow_Item>();
        List<UI_ScrollFlow_Item> right = new List<UI_ScrollFlow_Item>();
        List<UI_ScrollFlow_Item> middle = new List<UI_ScrollFlow_Item>();

        int index = 0;
        // Debug.LogError("LateUpdate:::" + useItemList.Count);
        for (int i = 0; i < useItemList.Count; i++)
        {
            float abs = Mathf.Abs(startValue - useItemList[i].v);
            if (abs < 0.05f)
            {
                middle.Add(useItemList[i]);
            }
            else
            {
                if (useItemList[i].v > startValue)
                {
                    right.Add(useItemList[i]);
                }
                else
                {
                    left.Add(useItemList[i]);
                }
            }
        }
        ////按照  顺序重新绘制  左侧  索引     右侧绘制从大到小

        left.Sort(sortByIndex);
        right.Sort(sortByIndex);


        for (int i = 0; i < left.Count; i++)
        {
            left[i].rect.SetSiblingIndex(index);
            index++;
        }

        for (int i = right.Count - 1; i >= 0; i--)
        {
            right[i].rect.SetSiblingIndex(index);
            index++;
        }
        for (int i = 0; i < middle.Count; i++)
        {
            middle[i].rect.SetSiblingIndex(index);
            index++;
        }

        IsOPenReDraw = false; 

    }

    private bool IsOPenReDraw = false;

    /// <summary>
    /// 
    /// </summary>
    public void RefreshDraw()
    {    
           // 停止创建元素
        ////StopCoroutine("ReDraw");
        ////StartCoroutine("ReDraw");
        IsOPenReDraw = true;
    }

    ////private IEnumerator ReDraw()
    ////{
    ////    Dictionary<int, UI_ScrollFlow_Item> xx = new Dictionary<int, UI_ScrollFlow_Item>();

    ////    foreach (UI_ScrollFlow_Item ele in useItemList)
    ////    {
    ////        xx.Add(ele.ResetSiblingIndex(), ele);
    ////    }

    ////    List<int> temp = new List<int>();
    ////    temp.AddRange(xx.Keys);
    ////    temp.Sort();

    ////    temp.Reverse();

    ////    foreach (int key in temp)
    ////    {
    ////        xx[key].rect.SetAsLastSibling();
    ////    }
    ////    yield return null;
    ////}

    private int sortByIndex(UI_ScrollFlow_Item item1, UI_ScrollFlow_Item item2)
    {
        int result = 0;
        if (item1.Index > item2.Index)
        {
            result = 1;
        }
        else if (item1.Index < item2.Index)
        {
            result = -1;
        }

        return result;
    }

    /// <summary>
    /// 移动结束
    /// </summary>
    /// <param name="k">移动距离</param>
    public void AnimToEnd(float k)
    {
        AddV = k;
        if (AddV > 0)
        {
            Vk = 1;
        }
        else if (AddV < 0)
        {
            Vk = -1;
        }
        else
        {
            return;
        }

        Vtotal = 0;
        _anim_speed = GetMoveSpeed(k);
        _anim = true;
    }

    /// <summary>
    /// 
    /// </summary>
    private void Update()
    {
        if (_anim)
        {
            CurrentV = Time.deltaTime * _anim_speed * Vk;
            ////通过update 来累加   CurrentV;
            ////直到移动量,达到要求的结束动画.
            ////主要对点击某个卡牌,移动直到显示某个具体位置卡牌有效.
            VT = Vtotal + CurrentV;

            if (Vk > 0 && VT >= AddV)
            {
                _anim = false;
                CurrentV = AddV - Vtotal;
            }

            if (Vk < 0 && VT <= AddV)
            {
                _anim = false;
                CurrentV = AddV - Vtotal;
            }
            ////=============================================
            for (int i = 0; i < useItemList.Count; i++)
            {
                useItemList[i].Drag(CurrentV);
                if (useItemList[i].v - startValue < 0.05f)
                {
                    Current = useItemList[i];
                }
            }

            Vtotal = VT;

            if (!_anim)
            {
                lastCurIndex = Current.Index;
           
                //setUpdateRectItem(lastCurIndex);
                if (MoveEnd != null)
                {
                    MoveEnd(Current);
                }
            }
        }
    }

    /// <summary>
    /// 转到指定子对象显示
    /// </summary>
    /// <param name="script"></param>
    public void ToAppointedItem(UI_ScrollFlow_Item script)
    {
        if (script == null)
            return;
        float k = script.v;
        k = startValue - k;

        AnimToEnd(k);
    }
}