// Biografsal med nulstilling

import java.awt.*;
import java.awt.event.*;

public class Biograf6 {

  public static void main(String[] args) {
    boolean[][] sal1 = new boolean[5][6];
    new BiografVindue("Sal 1", sal1);
  }
}

class BiografVindue extends ClosableFrame {
  Button nulstil;
  BiografCanvas biocanvas;
  boolean[][] bio;

  BiografVindue(String titel, boolean[][] bio) {
    super(titel);
    this.bio = bio;
    biocanvas = new BiografCanvas(bio);
    Panel p = new Panel();
    nulstil = new Button("Nulstil");
    p.add(nulstil);
    add(p, "North");
    add(biocanvas, "South");
    pack(); show();
    nulstil.addActionListener(new NulstilLytter());
  }

  class NulstilLytter implements ActionListener {
    public void actionPerformed(ActionEvent e) {
      for (int r=0; r<bio.length; r=r+1) 
	for (int s=0; s<bio[r].length; s=s+1) 
	  bio[r][s] = false;
      biocanvas.repaint();
    }
  }
}

class BiografCanvas extends Canvas {
  boolean[][] bio;

  BiografCanvas(boolean[][] bio) { 
    this.bio = bio; 
    addMouseListener(new ReservationListener());
  }

  class ReservationListener extends MouseAdapter {
    public void mouseClicked(MouseEvent e) {
      int r = (e.getY() - 10) / 20;
      int s = (e.getX() - 10) / 20;
      if (0 <= r  && 0 <= s && r < bio.length && s < bio[r].length)
        bio[r][s] = true;	  
      repaint();
    }
  }

  public void paint(Graphics gr) { 
    setBackground(Color.white);
    for (int r=0; r<bio.length; r=r+1) {
      for (int s=0; s<bio[r].length; s=s+1) {
	if (bio[r][s])			// Optaget
	  gr.setColor(Color.gray);
	else				// Ledig
	  gr.setColor(Color.yellow);
	gr.fillOval(10+s*20, 10+r*20, 15, 15);
      }
    }
  }

  public Dimension getPreferredSize() 
  { return new Dimension(300, 300); }

  public Dimension getMinimumSize()
  { return getPreferredSize(); }
}