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

public class Scribble extends Applet
{
    private int last_x, last_y;
    private Color current_color=Color.black;
    private Button clear_button;
    private Choice color_choices;

    public void init()
    {
	this.setBackground(Color.white);

	clear_button=new Button("Clear");
	clear_button.setForeground(Color.black);
	clear_button.setBackground(Color.lightGray);
        this.add(clear_button);

	color_choices=new Choice();
	color_choices.addItem("black");
	color_choices.addItem("red");
	color_choices.addItem("yellow");
	color_choices.addItem("green");

	color_choices.setForeground(Color.black);
	color_choices.setBackground(Color.lightGray);

	this.add(new Label("Color: "));
	this.add(color_choices);
    }

    public boolean mouseDown(Event e, int x, int y)
    {
	last_x = x;
	last_y = y;
	return true;
    }

    public boolean mouseDrag(Event e, int x, int y)
    {
	Graphics g = this.getGraphics();
	g.setColor(current_color);
	g.drawLine(last_x, last_y, x, y);
	last_x = x;
	last_y = y;
	return true;
    }

    public boolean action(Event event, Object arg)
    {
	if (event.target==clear_button)
	{
	    Graphics g = this.getGraphics();
	    Rectangle r = this.bounds();
	    g.setColor(this.getBackground());
	    g.fillRect(r.x, r.y, r.width, r.height);
	    return true;
	}
	else if (event.target==color_choices)
	{
	         if (arg.equals("black"))  current_color = Color.black;
	    else if (arg.equals("red"))    current_color = Color.red;
	    else if (arg.equals("yellow")) current_color = Color.yellow;
	    else if (arg.equals("green"))  current_color = Color.green;
	    return true;
	}
	else return super.action(event, arg);
    }
}