using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace StaffLayoutCtl
{
    public partial class grid : Control
    {

        public Boolean DeveloperMode = true;
        private Point GridCount = new Point(30, 20);
        private CGrid[,] gridrect = null;

        public grid()
        {
            InitializeComponent();

            // Set Optimized Double Buffer to reduce flickering
            this.SetStyle(ControlStyles.UserPaint, true);
            this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);
            this.SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
            this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);

            // Redraw when resized
            this.SetStyle(ControlStyles.ResizeRedraw, true);
            this.Resize += arLabel_Resize;
            this.MouseDown += grid_MouseDown;
            this.MouseMove += grid_MouseMove;
            this.MouseUp += grid_MouseUp;

             gridrect = new CGrid[GridCount.X, GridCount.Y];
        }

        void grid_MouseUp(object sender, MouseEventArgs e)
        {
            Boolean bOK = false;
            if(mousedn && mouseDrag && selectindex != -1 && diffrect != RectangleF.Empty)
            {
                if(Math.Abs(mousediff.X) >= 10 && Math.Abs(mousediff.Y) >= 10)
                {
                    //좌측코드가 속한 row,col 값으로 이동한다.
                    for(int i = 0; i<= gridrect.GetUpperBound(0);i++)
                    {
                        for (int j = 0; j <= gridrect.GetUpperBound(1); j++)
                        {
                            var grid = this.gridrect[i, j];
                            if(grid.Rect.Contains( diffrect.Location ))
                            {
                                var item = this.Items[selectindex];
                                item.Row = grid.Row;
                                item.Col = grid.Col;
                                bOK = true;
                                break;
                            }
                        }
                        if (bOK) break;
                    }
                }
            }
            mousedn = false;
            mouseDrag = false;            
            this.Invalidate();
        }

        void grid_MouseMove(object sender, MouseEventArgs e)
        {
            mousepos = e.Location;
            if (mousedn) mouseDrag = true;
            else mouseDrag = false;

            //선택개체 위로 오면 마우스 모양을 변경한다.
            if (selectindex < 0)
            {
                if (this.Cursor != Cursors.Arrow)
                {
                    this.Cursor = Cursors.Arrow;
                    this.Invalidate();
                }

            }
            else
            {
                var item = Items[selectindex];

                //중앙부에 있다면 이동형 핸드를
                //외곽에 있다면 크기 조정용 을 표시한다.

                //크기조정용 영역을 게산한다.
                RectangleF rectt = new RectangleF(item.Rect.Left, item.Rect.Top - 10, item.Rect.Width, 20);
                RectangleF rectb = new RectangleF(item.Rect.Left, item.Rect.Bottom - 10, item.Rect.Height, 20);
                RectangleF rectl = new RectangleF(item.Rect.Left - 10, item.Rect.Top, 20, item.Rect.Height);
                RectangleF rectr = new RectangleF(item.Rect.Right - 10, item.Rect.Top, 20, item.Rect.Height);

                if (rectt.Contains(e.Location))
                {
                    if (this.Cursor != Cursors.PanNorth)
                    {
                        this.Cursor = Cursors.PanNorth;
                        this.Invalidate();
                    }
                }
                else if (rectb.Contains(e.Location))
                {
                    if (this.Cursor != Cursors.PanSouth)
                    {
                        this.Cursor = Cursors.PanSouth;
                        this.Invalidate();
                    }
                }
                else if (rectl.Contains(e.Location))
                {
                    if (this.Cursor != Cursors.PanWest)
                    {
                        this.Cursor = Cursors.PanWest;
                        this.Invalidate();
                    }
                }
                else if (rectr.Contains(e.Location))
                {
                    if (this.Cursor != Cursors.PanEast)
                    {
                        this.Cursor = Cursors.PanEast;
                        this.Invalidate();
                    }
                }
                else if (item.Rect.Contains(e.Location))
                {
                    if (this.Cursor != Cursors.Hand)
                    {
                        this.Cursor = Cursors.Hand;
                        this.Invalidate();
                    }
                }
                else
                {
                    if (this.Cursor != Cursors.Arrow)
                    {
                        this.Cursor = Cursors.Arrow;
                        this.Invalidate();
                    }
                    else
                    {
                        if (mousedn)
                        {


                        }
                    }
                }
                this.Invalidate(); //화면이 업데이트되도록 함
            }
        }

        Boolean mouseDrag = false;
        Boolean mousedn = false;
        Point mousednpos = Point.Empty;
        Point mousepos = Point.Empty;
        int selectindex = -1;
        void grid_MouseDown(object sender, MouseEventArgs e)
        {
            mousedn = true;
            //save down point
            mousednpos = e.Location;

            //선택된 아이템을 찾아야한다.
            Boolean selected = false;
            int r = 0;
            int c = 0;
            for (int i = 0; i < Items.Count; i++)
            {
                var item = Items[i];
                if (item.Rect.Contains(e.Location))
                {
                    selectindex = i;
                    selected = true;
                    r = item.Row;
                    c = item.Col;
                    selectRect = item.Rect;
                    //다른 아이템의 선택을 해제한다.
                    Console.WriteLine(string.Format("select item : {0}/{1}", item.Row, item.Col));
                    break;
                }
            }
            if (selected)
            {
                foreach (var item in Items)
                {
                    if (item.Row == r && item.Col == c) item.Select = true;
                    else item.Select = false;
                }
            }
            else
            {
                selectindex = -1;
                var selitem = Items.Where(t => t.Select);
                foreach (var item in selitem)
                    item.Select = false;
            }
            Invalidate();
        }
        void arLabel_Resize(object sender, EventArgs e)
        {
            Make_Grid();
            Invalidate();
        }

        Point mousediff = Point.Empty;
        RectangleF diffrect = RectangleF.Empty;

        protected override void OnPaint(PaintEventArgs pe)
        {
            base.OnPaint(pe);
            Draw_Grid(pe.Graphics);
            Draw_Item(pe.Graphics);

            if (mouseDrag && mousedn && selectindex != -1 && mousednpos != Point.Empty)
            {
                mousediff = new Point(mousepos.X - mousednpos.X, mousepos.Y - mousednpos.Y);

                //이동영역을 
                diffrect = new RectangleF(selectRect.Left + mousediff.X,
                   selectRect.Top + mousediff.Y,
                   selectRect.Width, selectRect.Height);

                using(SolidBrush sb = new SolidBrush(Color.FromArgb(100,Color.Gray)))
                {
                    pe.Graphics.FillRectangle(sb, diffrect);
                }

                pe.Graphics.DrawRectangle(Pens.DimGray, diffrect.Left, diffrect.Top, diffrect.Width, diffrect.Height);
            }
            Draw_Debug(pe.Graphics);

        }
        void Draw_Debug(Graphics g)
        {
            System.Text.StringBuilder sb = new StringBuilder();
            sb.AppendLine("diff = " + mousediff.ToString());
            sb.AppendLine("drag : " + mouseDrag.ToString());
            sb.AppendLine("mouse down : " + mousedn.ToString() + ", " + mousednpos.ToString());
            sb.AppendLine("mouse pos : " + this.mousepos.ToString());
            sb.AppendLine("select index : " + this.selectindex.ToString() + "," + this.selectRect.ToString());
            sb.AppendLine("sel rect : " + this.selectRect.ToString());
            sb.AppendLine("diff rect : " + this.diffrect.ToString());
            sb.AppendLine("cell size : " + cellSize.ToString());
            using (Font f = new Font("Consolas", 20f))
            {
                g.DrawString(sb.ToString(), f, Brushes.Black, 50 - 1, 50 - 1);
                g.DrawString(sb.ToString(), f, Brushes.Black, 50 - 1, 50 + 1);
                g.DrawString(sb.ToString(), f, Brushes.Black, 50 + 1, 50 - 1);
                g.DrawString(sb.ToString(), f, Brushes.Black, 50 + 1, 50 + 1);
                g.DrawString(sb.ToString(), f, Brushes.Red, 50, 50);
            }

        }
        public List<CItem> Items = new List<CItem>();
        RectangleF selectRect = RectangleF.Empty;
        SizeF cellSize = SizeF.Empty;
        void Draw_Item(Graphics g)
        {
            if (DeveloperMode)
            {
                //demo item 
                Items.Clear();
                Items.Add(new CItem(r: 1, c: 1, rs: 2, cs: 2, text: "김치균", bg: Color.White.ToArgb()));
                Items.Add(new CItem(4, 4, 1, 1, "박성민"));
                Items.Add(new CItem(6, 6, 10, 3, "고진일"));
                Items.Add(new CItem(7, 7, 2, 2, "테스트"));
                Items[1].Select = true;
            }

            int idx = 0;
            foreach (var item in Items)
            {
                float x = item.Col * cellSize.Width;
                float y = item.Row * cellSize.Height;
                float w = item.ColSpan * cellSize.Width;
                float h = item.RowSpan * cellSize.Height;
                RectangleF rectf = new RectangleF(x, y, w, h);
                g.FillRectangle(Brushes.Yellow, rectf);
                item.Rect = rectf;
                if (item.Select)
                {
                    g.DrawRectangle(new Pen(Color.Blue, 4f),
                        rectf.Left, rectf.Top, rectf.Width, rectf.Height);

                    //크기조정을 위한 좌우 화살표가 필요하다.
                }

                string data = idx.ToString();
                if (item.Text != "'") data = item.Text;
                g.DrawString(data + item.Select.ToString(), this.Font, Brushes.Black, x, y);
                idx += 1;
            }
        }
        void Make_Grid()
        {
            float gw = DisplayRectangle.Width / GridCount.Y;
            float gh = DisplayRectangle.Height / GridCount.X;
            cellSize = new SizeF(gw, gh);
            for (int i = 0; i < GridCount.X; i++)
            {
                for (int j = 0; j < GridCount.Y; j++)
                {
                    int idx = (i * GridCount.Y) + j;                    
                    RectangleF rect = new RectangleF(j * gw, i * gh, gw, gh); ;
                    this.gridrect[i, j] = new CGrid(idx);
                    this.gridrect[i, j].Rect = rect;
                    this.gridrect[i, j].Row = i;
                    this.gridrect[i, j].Col = j;
                }
            }
        }

        void Draw_Grid(Graphics g)
        {
            if(gridrect[0,0]== null) Make_Grid();

            for (int i = 0; i <= gridrect.GetUpperBound(0); i++)
            {
                for (int j = 0; j <= gridrect.GetUpperBound(1); j++)
                {
                    var grid = this.gridrect[i, j];
                    g.DrawRectangle(Pens.Black, grid.Rect.Left, grid.Rect.Top, grid.Rect.Width, grid.Rect.Height);
                    g.DrawString(grid.IDX.ToString(), this.Font, Brushes.Blue, grid.Rect.Left, grid.Rect.Top);
                }
            }

        }
    }
}