using UnityEngine;
using UnityEngine.EventSystems;
using System.Runtime.InteropServices;
using System.Collections.Generic;
using System;
//[ExecuteAlways]
public class GridSelector : MonoBehaviour
{
    public struct RenderData
    {
        public int barrier; //阻隔点，高度值
        public float isSelected;
        public float r;
        public float g;
        public float b;
    }
    [Space]
    [Range(0f, 1f)]
    [Header("调整透明度")]
    public float gridAlpha = 1;
    private MeshRenderer mapRenderer;
    private MeshCollider mapCollider;

    private Map map;
    public int horizontalNumber { get { return Mathf.CeilToInt(map.width / map.sideWidth); } }
    public int verticalNumber { get { return Mathf.CeilToInt(map.height / map.sideHeight); } }
    public int totalNumber { get { return horizontalNumber * verticalNumber; } }

    public int moveNum;

    private ComputeBuffer inputbuffer;
    public RenderData[] dataArray;
    
    public List<int> selectedGridIndex = new List<int>();
    private int shiftBeginIndex;

    private List<Vector2> lassoPos = new List<Vector2>();
    private LineRenderer lassoLine;

    public CellType getCellType(int index)
    {
        return (CellType)dataArray[index].barrier;
    }
    public CellType CellType { set; get; }
    public void OnMapCreated(Map map)
    {
        this.map = map;
        moveNum = 0;
        mapRenderer.material.SetVector("_Size", new Vector4(horizontalNumber, verticalNumber));
        mapRenderer.material.SetFloat("_UserInput", 1);
        inputbuffer = new ComputeBuffer(totalNumber, Marshal.SizeOf(typeof(RenderData)));
        dataArray = new RenderData[totalNumber];
        //创建新的地图默认为全部是可行走区域
        for (int i = 0; i < totalNumber; i++)
        {
            dataArray[i].barrier = (int)CellType.Move;
        }
        RefreshPlaneRender();
    }
    public RenderData[] GetGridData()
    {
        return dataArray;
    }
    public void setdataArrayIndex(int index,float cellheight, int barrier)
    {
        if (index >= dataArray.Length)
            return;
        int height = (int)(cellheight * 100);
        height += 10000;
        int mask = dataArray[index].barrier & 0xFFFF;
        //去除之前的8-16位
        //mask &= 0xFF;
        //移除之前的信息值再加新的
        mask &= ~(int)CellType.Move;
        mask &= ~(int)CellType.Obstacle;
        mask |= barrier;
        //先取出之前的高度值
        dataArray[index].barrier = height << 16;
        dataArray[index].barrier |= mask;
        setDataColor(index);
    }
    public int getdataByPos(Vector3 pos)
    {
        int hitIndex = Mathf.FloorToInt(pos.x / map.sideWidth) + Mathf.FloorToInt(pos.z / map.sideHeight) * horizontalNumber;
        return hitIndex;
    }
    public Vector2Int getMapGrid(Vector3 pos)
    {
        return getMapGrid(new Vector2(pos.x,pos.y));
    }


    public Vector2Int getMapGrid(Vector2 pos)
    { 
        var grid = new Vector2Int();
        grid.x = Mathf.FloorToInt(pos.x / map.sideWidth);
        grid.y = Mathf.FloorToInt(pos.y / map.sideHeight);
        return grid;
    }
    public Vector2 getPosByGrid(Vector2Int grid)
    {
        return new Vector2(grid.x * map.sideWidth + map.sideWidth/2, grid.y * map.sideHeight + map.sideHeight / 2);
    }
    private void Awake()
    {
        mapRenderer = GetComponent<MeshRenderer>();
        mapCollider = GetComponent<MeshCollider>();
        GameObject go = GameObject.Instantiate(MapManager.Instance.line.gameObject);
        go.transform.SetParent(transform);
        lassoLine = go.GetComponent<LineRenderer>();
        lassoLine.positionCount = 0;
        lassoLine.startWidth = 0.1f;
        lassoLine.endWidth = 0.1f;
        lassoLine.gameObject.SetActive(false);
    }
    private void OnDestroy()
    {
        if (inputbuffer != null)
        {
            inputbuffer.Release();
        }
    }
    private int GetIndexByXY(int x, int y) {
        int index = x + y * horizontalNumber;
        return index;
    }
    /// <summary>
    /// 这里采用的算法是每行从左到右的算法，但是过滤了已经重复过的格子
    /// *************
    /// *****678*****
    /// *****4*5*****
    /// *****123*****
    /// *************
    /// </summary>
    /// <param name="index"></param>
    /// <returns></returns>
    private int FindMapHeight(int index) {
        GetXyByIndex(index, out int oldx, out int oldy);
        //像外扩展，找到一个邻近的高度值
        int maxR = 1000;
        int stepI;
        for (int r = 1; r < maxR; r++)
        {
            for (int j = -r; j <= r; j++)
            {
                if (j == -r || j == r)
                {
                    stepI = 1;
                }
                else
                {
                    stepI = r * 2;
                }
                for (int i = -r; i <= r; i += stepI)
                {
                    int x = oldx + i;
                    int y = oldy + j;
                    if (x < 0 || x >= horizontalNumber || y < 0 || y >= verticalNumber) {
                        continue;
                    }
                    int neighborIndex = x + y * horizontalNumber;
                    int neighborValue = dataArray[neighborIndex].barrier;
                    if (neighborValue != 0)
                    {
                        return neighborValue;
                    }
                }
            }
        }
        return 1;
    }
    float lastAlpha = 1;
    private void Update()
    {
        if (lastAlpha != gridAlpha)
        {
            map.ChangeGridAlpha(gridAlpha);
            lastAlpha = gridAlpha;
        }
        //先处理移动区域，要先处理之前的区域数据
        if (Input.GetKeyDown(KeyCode.C))
        {
            for (int i = 0, length = selectedGridIndex.Count; i < length; i++)
            {
                int index = selectedGridIndex[i];
                //if ((dataArray[index].barrier & (int)CellType.Obstacle) != 0)
                //{
                //    dataArray[index].barrier &= ~(int)CellType.Obstacle;
                //}
                //dataArray[index].barrier |= (int)CellType.Move;
                setDataCellType(index, true);
            }

            RefreshPlaneRender();
        }
        if (Input.GetKeyDown(KeyCode.X))
        {
            for (int i = 0, length = selectedGridIndex.Count; i < length; i++)
            {
                int index = selectedGridIndex[i];
                //if ((dataArray[index].barrier & (int)CellType.Move) != 0)
                //{
                //    dataArray[index].barrier &= ~(int)CellType.Move;
                //}
                //dataArray[index].barrier |= (int)CellType.Obstacle;
                setDataCellType(index, false);
            }
            RefreshPlaneRender();
        }
        if (Input.GetKeyUp(KeyCode.Z))
        {
            lassoPos.Clear();
            lassoLine.gameObject.SetActive(false);
            lassoLine.positionCount = 0;
        }


        if (Input.GetMouseButtonDown(0))
        {
            if (mapCollider.Raycast(Camera.main.ScreenPointToRay(Input.mousePosition), out RaycastHit hit, float.PositiveInfinity))
            {
                Vector2 hitUv = hit.textureCoord;
                int hitIndex = Mathf.FloorToInt(hitUv.x * horizontalNumber) + Mathf.FloorToInt(hitUv.y * verticalNumber) * horizontalNumber;

                if (!Input.GetKey(KeyCode.LeftShift))
                {
                    if (Input.GetKey(KeyCode.LeftControl))
                    {
                        shiftBeginIndex = hitIndex;
                        SetGridIndexSelected(hitIndex, dataArray[hitIndex].isSelected != 1f);
                        RefreshPlaneRender();
                    }
                    else if (Input.GetKey(KeyCode.Z))
                    {
                        Vector2 hitPos = GetCenterPosByIndex(hitIndex);

                        if (lassoPos.Count == 0 || lassoPos[0] != hitPos)
                        {
                            if (lassoPos.Count == 0)
                            {
                                SetAllUnselected();
                            }
                            SetGridIndexSelected(hitIndex, true);

                            lassoLine.gameObject.SetActive(true);
                            lassoLine.positionCount++;
                            lassoLine.SetPosition(lassoLine.positionCount - 1, new Vector3(hitPos.x,transform.position.y + 0.1f, hitPos.y));
                            lassoPos.Add(hitPos);
                        }
                        else
                        {
                            lassoLine.positionCount++;
                            lassoLine.SetPosition(lassoLine.positionCount - 1, new Vector3(hitPos.x,transform.position.y + 0.1f, hitPos.y));
                            lassoPos.Add(hitPos);
                            
                            for (int i = 0; i < totalNumber; i++)
                            {
                                Vector2 gridPos = GetCenterPosByIndex(i);
                                bool isSelected = false;
                                for (int j = 0, length = lassoPos.Count - 1; j < length; j++)
                                {
                                    Vector2 pos0 = lassoPos[j];
                                    Vector2 pos1 = lassoPos[j + 1];

                                    if (Pnpoly(gridPos, pos0, pos1))
                                    {
                                        isSelected = !isSelected;
                                    }
                                }
                                SetGridIndexSelected(i, isSelected);
                            }
               
                        }
                        if (lassoLine.positionCount == 2)
                        {
                            //CSSMoveMgr.Instance.FindPath(lassoPos[0], lassoPos[1]);
                            //在这里寻找路径
                        }
                        RefreshPlaneRender();
                    }
                    else if (!Input.GetKey(KeyCode.LeftAlt))    //左alt键涉及到镜头操作，所以屏蔽掉
                    {
                        shiftBeginIndex = hitIndex;
                        SetAllUnselected();
                        SetGridIndexSelected(hitIndex, true);
                        RefreshPlaneRender();
                    }
                }
            }
            else
            {
                SetAllUnselected();
                RefreshPlaneRender();
            }
        }
        else if (Input.GetMouseButton(0))
        {
            if (mapCollider.Raycast(Camera.main.ScreenPointToRay(Input.mousePosition), out RaycastHit hit, float.PositiveInfinity))
            {
                if (Input.GetKey(KeyCode.LeftShift))
                {
       
                    Vector2 hitUv = hit.textureCoord;
                    int hitIndex = Mathf.FloorToInt(hitUv.x * horizontalNumber) + Mathf.FloorToInt(hitUv.y * verticalNumber) * horizontalNumber;
                    int beginX, beginY;
                    GetXyByIndex(shiftBeginIndex, out beginX, out beginY);
                    int hitX, hitY;
                    GetXyByIndex(hitIndex, out hitX, out hitY);
                    beginPos.x = beginX;
                    beginPos.z = beginY;
                    endPos.x = hitX;
                    endPos.z = hitY;
                    //CSSMoveMgr.Instance.FindPath(new Vector3(beginX,0,beginY),new Vector3(hitX,0,hitY));
                    ShiftKeySelect(hitIndex);
                    RefreshPlaneRender();
                }
            }
        }
    }
    private Vector3 beginPos = new Vector3();
    private Vector3 endPos = new Vector3();
    private void OnGUI()
    {
        GUIStyle style = new GUIStyle() { fontSize = 30 };
        style.normal.textColor = Color.red;
        int width = Screen.width;
        int height = Screen.height;
        GUI.Label(new Rect(width - 320, height - 150, 400, 50), "按住Shift按钮多选", style);
        GUI.Label(new Rect(width - 320, height - 100, 400, 50), "选中后C键取消格子信息", style);
        GUI.Label(new Rect(width - 320, height - 50, 400, 50), "选中后X键确定格子信息", style);
        style.normal.textColor = Color.green;
        if (selectedGridIndex.Count == 0)
        {
            return;
        }
        else if (selectedGridIndex.Count == 1)
        {
            int beginIndex = selectedGridIndex[0];
            GetXyByIndex(beginIndex, out int x, out int y);
            string labelText = string.Format(
            "所选点XY序列：({0},{1})",
            x, y);
            Vector2 labelSize = style.CalcSize(new GUIContent(labelText));
            GUI.Label(
                new Rect(Screen.width - labelSize.x - 20, 20, labelSize.x, labelSize.y),
                labelText,
                style
            );
            //GUI.Label(new Rect(width - 820, 20, 400, 50), string.Format("所选点XY序列：({0},{1}) 高度{2} 点类型 {3}", x, y, ((dataArray[beginIndex].barrier >> 16) - 10000)/100.0f, CellTypeColors.GetAreaStr((dataArray[beginIndex].barrier)), style));
           
        }
        else
        {
            int beginIndex = selectedGridIndex[0];
            int endIndex = selectedGridIndex[selectedGridIndex.Count - 1];

            GetXyByIndex(beginIndex, out int x0, out int y0);
            GetXyByIndex(endIndex, out int x1, out int y1);

            GUI.Label(new Rect(width - 420, 20, 400, 50), string.Format("所选起点XY序列：({0},{1})", x0, y0), style);
            GUI.Label(new Rect(width - 420, 90, 400, 50), string.Format("所选终点XY序列：({0},{1})", x1, y1), style);
        }
        
    }

    private void SetGridIndexSelected(int index, bool isSelected)
    {
        if (isSelected)
        {
            if (!selectedGridIndex.Contains(index))
            {
                selectedGridIndex.Add(index);
                dataArray[index].isSelected = 1f;
            }
        }
        else
        {
            selectedGridIndex.Remove(index);
            dataArray[index].isSelected = 0f;
        }
    }
    private void setDataColor(int index) {
        Color color = CellTypeColors.GetColor((CellType)dataArray[index].barrier);
        dataArray[index].r = color.r;
        dataArray[index].g = color.g;
        dataArray[index].b = color.b;
    }
    private void setDataCellType(int index,bool IsCancel)
    {
        if (UICellEditor.Instance == null) return;
        if (UICellEditor.Instance.editorGrid == CellType.Move ||
            UICellEditor.Instance.editorGrid == CellType.Obstacle)
        {
            if (IsCancel)
            {
                if ((dataArray[index].barrier & (int)CellType.Obstacle) != 0)
                {
                    dataArray[index].barrier &= ~(int)CellType.Obstacle;
                }
                dataArray[index].barrier |= (int)CellType.Move;
            }
            else
            {
                if ((dataArray[index].barrier & (int)CellType.Move) != 0)
                {
                    dataArray[index].barrier &= ~(int)CellType.Move;
                }
                dataArray[index].barrier |= (int)CellType.Obstacle;
            }
        }
        else if (UICellEditor.Instance.editorGrid == CellType.Safe)
        {
            if (IsCancel)
            {
                if ((dataArray[index].barrier & (int)CellType.Safe) != 0)
                {
                    dataArray[index].barrier &= ~(int)CellType.Safe;
                }
            }
            else
            {
                dataArray[index].barrier |= (int)CellType.Safe;
            }
        }
        else if (UICellEditor.Instance.editorGrid == CellType.Stall)
        {
            if (IsCancel)
            {
                if ((dataArray[index].barrier & (int)CellType.Stall) != 0)
                {
                    dataArray[index].barrier &= ~(int)CellType.Stall;
                }
            }
            else
            {
                dataArray[index].barrier |= (int)CellType.Stall;
            }
        }
        else if (UICellEditor.Instance.editorGrid == CellType.Hide)
        {
            if (IsCancel)
            {
                if ((dataArray[index].barrier & (int)CellType.Hide) != 0)
                {
                    dataArray[index].barrier &= ~(int)CellType.Hide;
                }
            }
            else
            {
                dataArray[index].barrier |= (int)CellType.Hide;
            }
        }
    }
    public void FullAllArea()
    {
        for (int i = 0; i < dataArray.Length; i++)
        {
            CellType cell = (CellType)dataArray[i].barrier;
            if (cell.HasFlag(CellType.Move))
            {
                dataArray[i].barrier &= ~(int)CellType.Move;
            }
            dataArray[i].barrier |= (int)CellType.Obstacle;
        }
        RefreshPlaneRender();
    }
    public void ClearSelectArea()
    {
        for (int i = 0; i < dataArray.Length; i++)
        {
            CellType cell = (CellType)dataArray[i].barrier;
            if (cell.HasFlag(CellType.Obstacle))
            {
                dataArray[i].barrier &= ~(int)CellType.Obstacle; 
            }
            dataArray[i].barrier |= (int)CellType.Move;
        }
        RefreshPlaneRender();
    }

    public void RefreshPlaneRender()
    {
        moveNum = 0;
        for (int i = 0; i < dataArray.Length; i++) {
            setDataColor(i);
            CellType cell = (CellType)dataArray[i].barrier;
            if (cell.HasFlag(CellType.Move))
            {
                moveNum++;
            }
        }
        inputbuffer.SetData(dataArray);
        mapRenderer.material.SetBuffer("_InputData", inputbuffer);
    }
    public void GetXyByIndex(int index,out int x,out int y)
    {
        x = index % horizontalNumber;
        y = index / horizontalNumber;
    }
    //TODO 这里有改动，应该是对的
    private Vector2 GetCenterPosByIndex(int index)
    {
        GetXyByIndex(index, out int x, out int y);
        return new Vector2((x + 0.5f)*map.sideWidth, (y + 0.5f) * map.sideHeight);
    }
    private bool Pnpoly(Vector2 gridPos, Vector2 pos0, Vector2 pos1)
    {
        bool tmp0 = (gridPos.y < pos1.y) != (gridPos.y < pos0.y);
        bool tmp1 = gridPos.x <= (pos0.x - pos1.x) * (gridPos.y - pos1.y) / (pos0.y - pos1.y) + pos1.x;

        return tmp0 && tmp1;
    }
    private void SetAllUnselected()
    {
        for (int i = selectedGridIndex.Count - 1; i >= 0; i--)
        {
            SetGridIndexSelected(selectedGridIndex[i], false);
        }
    }
    private void ShiftKeySelect(int hitIndex)
    {
        int beginX, beginY;
        GetXyByIndex(shiftBeginIndex, out beginX, out beginY);
        int hitX, hitY;
        GetXyByIndex(hitIndex, out hitX, out hitY);
        int minX = Mathf.Min(beginX, hitX);
        int maxX = Mathf.Max(beginX, hitX);
        int minY = Mathf.Min(beginY, hitY);
        int maxY = Mathf.Max(beginY, hitY);
        shiftBeginIndex = hitIndex;
        for (int y = 0; y < verticalNumber; y++)
        {
            for (int x = 0; x < horizontalNumber; x++)
            {
                bool isWithin = x >= minX && x <= maxX && y >= minY && y <= maxY;

                if (isWithin)
                {
                    int index = x + y * horizontalNumber;
                    SetGridIndexSelected(index, true);
                }
            }
        }
    }
    public Vector2Int GetMouseByCell()
    {
        Vector2Int cell = new Vector2Int();
        if (mapCollider.Raycast(Camera.main.ScreenPointToRay(Input.mousePosition), out RaycastHit hit, float.PositiveInfinity))
        {
            Vector2 hitUv = hit.textureCoord;
            cell.x = Mathf.FloorToInt(hitUv.x * horizontalNumber);
            cell.y = Mathf.FloorToInt(hitUv.y * verticalNumber);
        }
        return cell;
    }
    public Vector2Int GetMouseByCell(Vector3 mousePositon)
    {
        Vector2Int cell = new Vector2Int();
        if (mapCollider.Raycast(Camera.main.ScreenPointToRay(mousePositon), out RaycastHit hit, float.PositiveInfinity))
        {
            Vector2 hitUv = hit.textureCoord;
            cell.x = Mathf.FloorToInt(hitUv.x * horizontalNumber);
            cell.y = Mathf.FloorToInt(hitUv.y * verticalNumber);
        }
        return cell;
    }
}