using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Drawing;


namespace firstCSharp
{
  class FirstForm : Form
  {
    
    public FirstForm()
    {
      BackColor = Color.Tomato;
      Text = "Hello world!";
      Height = 600;
      const double GOLDEN_RATIO = 1.618;
      Width = (int) (Height * GOLDEN_RATIO);

      MouseClick += FirstForm_MouseClick;
      MouseMove += FirstForm_MouseMove;
            Paint += FirstForm_Paint;

      // Opacity = .5;
    }
        private void FirstForm_Paint(object sender, PaintEventArgs e)
        {
            // Draw a chessboard in the window.

            // Get the instance of class graphics that is associated 
            // with the client area of this window.
            Graphics graphics = e.Graphics;

            // ClientRectangle can provide the size of the client area
            int width = ClientRectangle.Width;
            int height = ClientRectangle.Height;

            // Find the smaller of the two dimensions 
            int squareSide = Math.Min(width, height);

            // Draw a square showing where the board will be
            graphics.DrawRectangle(Pens.Green,
                new Rectangle(new Point(0, 0), 
                new Size(squareSide, squareSide)));

            graphics.FillRectangle(Brushes.Green,
                new Rectangle(new Point(0, 0),
                new Size(squareSide, squareSide)));

            const int N_ROWS = 8;
            const int N_COLUMNS = 8;

            Brush lightSquareBrush = Brushes.Bisque;
            Brush darkSquareBrush = Brushes.DarkGreen;

            Brush nextSquare = lightSquareBrush;
            int smallSquare = squareSide / N_ROWS;
            for(int row=0;row<N_ROWS;++row)
            {
                for(int column=0;column<N_COLUMNS;++column)
                {
                    graphics.FillRectangle(nextSquare,
                        new Rectangle(column * smallSquare, row * smallSquare,
                        smallSquare, smallSquare));

                    nextSquare = (nextSquare == lightSquareBrush) ?
                        darkSquareBrush : lightSquareBrush;
                }
                    nextSquare = (nextSquare == lightSquareBrush) ?
                        darkSquareBrush : lightSquareBrush;
            }
        }

        // Messages are handled by a function called 
        // WndProc
        private const int WM_LBUTTONDOWN = 0x201;
        private const int MK_LBUTTON = 0x0001;
        private const int MK_RBUTTON = 0x0002;
        private const int MK_SHIFT = 0x0004;

    protected override void WndProc(ref Message m)
    {
       Console.WriteLine("Message Id is : {0}", m.Msg);
       Console.WriteLine("Message to string is: {0}",
                m.ToString());

       switch(m.Msg)
       {
           case WM_LBUTTONDOWN:
                    int iwparam = (int) m.WParam;
                    if ((iwparam & MK_LBUTTON) != 0)
                        Console.WriteLine("************LButton is up!");
                    if ((iwparam & MK_RBUTTON) != 0)
                        Console.WriteLine("************RButton is up!");
                    if ((iwparam & MK_SHIFT) != 0)
                        Console.WriteLine("************Shift is down!");

                    int iLParam = (int) m.LParam;
                    int x = iLParam & 0x0000ffff;
                    int y = (iLParam >> 16) & 0x0000ffff;

                    Console.WriteLine("xy coord is ({0}, {1})",
                        x, y);

                    break;
       }

       //if (m.Msg != WM_LBUTTONDOWN)
       {
           base.WndProc(ref m);
       }
    }

    private void FirstForm_MouseMove(object sender, MouseEventArgs e)
    {
      Text = String.Format("({0}, {1})", e.X, e.Y);
    }

    private void FirstForm_MouseClick(object sender, 
      MouseEventArgs e)
    {
      if (BackColor == Color.Tomato)
      {
        BackColor = Color.Chartreuse;
      }
      else
      {
        BackColor = Color.Tomato;
      }
    }
  }
}