import java.awt.*;
import java.applet.Applet;


public class Asst7 extends Applet {
    DrawingCanvas canvas;

    public void init() {
        GridLayout grid = new GridLayout(1,0);
        setLayout(grid);

	add (new DrawingCanvas());
	
        validate();
    }

}


class DrawingCanvas extends Canvas {

  private Dimension rectangleSize;
  private int pressedX;
  private int pressedY;
  
  // constructor
  public DrawingCanvas() {
    super();
    rectangleSize = null;
    pressedX = pressedY = -1;
  }

  // called when mouse button is pressed
  // (x,y) is position of mouse press
  //   ignore the event parameter
    public boolean mouseDown(Event event, int x, int y) {

      // (for debugging purposes?)
      System.out.println ("mouse pressed at (" + x + ", " + y + ")");

      pressedX = x;
      pressedY = y;
      repaint();  // asks system to call paint() sometime soon
      return false;
    }


  // called when mouse is moved while holding down the button
  public boolean mouseDrag(Event event, int x, int y) {
    rectangleSize = new Dimension(x-pressedX, y-pressedY);
    repaint();
    return false;
  }

  // called when mouse button is released
  public boolean mouseUp(Event event, int x, int y) {
    rectangleSize = new Dimension(x-pressedX, y-pressedY);
    repaint();
    return false;
  }

  public void paint(Graphics g) {
    Dimension d = size();

    if (pressedX >= 0) {
      g.setColor(Color.blue);
      g.drawLine(0, pressedY, pressedX, pressedY);
      g.setColor(Color.red);
      g.drawLine(d.width, pressedY, pressedX, pressedY);
      g.setColor(Color.green);
      g.drawLine(pressedX, 0, pressedX, pressedY);
      g.setColor(Color.magenta);
      g.drawLine(pressedX, d.height, pressedX, pressedY);
    }
    
      
    if (rectangleSize != null) {
      g.setColor(Color.yellow);
      int x = pressedX;
      int y = pressedY;
      int w = rectangleSize.width - 1;
      int h = rectangleSize.height - 1;

      if (w < 0) {
	x += w;
	w *= -1;
      }
      if (h < 0) {
	y += h;
	h *= -1;
      }
      
      g.fillRect(x, y, w, h);
    }
  }

}