import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.image.BufferedImage;

import javax.swing.*;

/**
 * @author Brad Chase
 * A Simple Swing Application
 * 
 */
public class MainWindow2 extends JComponent implements ActionListener {
    private DrawingComponent canvas;
    private static void createGUI() {
        MainWindow2 mainWindow = new MainWindow2();
        JFrame frame = new JFrame("Amazing Swing App");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(new Dimension(400, 300));
        /*** setup menu ***/
        JMenuBar menuBar = new JMenuBar(); /* the menu bar itself */
        JMenu menu = new JMenu("File"); /* create a new menu */
        menuBar.add(menu); /* add the menu to the menu bar that 
                                                   will contain it*/
        JMenuItem item = new JMenuItem("Exit"); /* add an exit option */
        item.addActionListener(mainWindow); /* this class will handle actions for this item */
        item.setActionCommand("exit"); /* this is the text that accompanies the action event */
        menu.add(item);
        frame.setJMenuBar(menuBar); /* add the menubar to the frame */
        /*** setup main window area */
        mainWindow.canvas = new DrawingComponent();
        frame.getContentPane().add(mainWindow);  /* add the main window component to the frame */
        mainWindow.setLayout(new BorderLayout());  /* use the border layout manager */
        mainWindow.add(mainWindow.canvas,BorderLayout.CENTER);
        
        
        frame.setVisible(true);
        frame.validate();
    }

    /**
     * @param e the action that occurred
     * @see java.awt.event.ActionListener#actionPerformed(java.awt.event.ActionEvent)
     */
    public void actionPerformed(ActionEvent e) {
        //we have to figure out what action occurred
        //to do so, we check the action command text in the actionevent
        if (e.getActionCommand().equals("exit")) {
            System.exit(0);
        }

    }

    private static class DrawingComponent extends JComponent implements MouseListener{
        private BufferedImage _buff;
        private int _w = 320, _h = 240;

        public DrawingComponent() {
            /* set our size*/
            this.setPreferredSize(new Dimension(_w, _h));
            this.setMaximumSize(new Dimension(_w, _h));
            this.setMinimumSize(new Dimension(_w, _h));
            this.setDoubleBuffered(true);
            /* create the buffer we will draw on */
            _buff = new BufferedImage(_w, _h, BufferedImage.TYPE_INT_RGB);
            this.addMouseListener(this);
            revalidate();
        }

        /**
        * Overridden paint method for JComponent. Mostly just draws the BufferedImage.
        */
        protected void paintComponent(Graphics g) {

            Graphics2D g2d = (Graphics2D)g.create();
            g2d.drawImage(_buff, 0, 0, this);
            g2d.dispose(); //clean up
        }
        private int max(int a,int b){
            return (a > b) ? a : b;
        }
        private int min(int a,int b){
            return (a < b) ? a : b;
        }
        public void mouseClicked(MouseEvent e) {
             for(int row = e.getX()-2;row<e.getX()+2;row++)
              for(int col = e.getY()-2;col<e.getY()+2;col++)
            _buff.setRGB(min(max(row,1),_w)-1,min(max(col,1),_h)-1,new Color(255,0,0).getRGB());
            repaint();
        }
        public void mouseEntered(MouseEvent e) {
        }

        public void mouseExited(MouseEvent e) {
        }

        public void mousePressed(MouseEvent e) {
        }

        public void mouseReleased(MouseEvent e) {
        }
    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createGUI();
            }
        });
    }

}