/** The Traffic light program from 'Java Gently' by JM Bishop,1996
    Displays a representation of traffic lights
    in preparation for a simulation.
    Illustrates panels and canvases and the BorderLayout Manager
*/    

import java.awt.*;

public class Traffic extends Frame {

    private Canvas area;
    private int lightsPosition = 105;
    private static final int lightsWidth = 150;
    private SetOfLights[] lights = new SetOfLights[3];
    private int lightsNo;
    private int setWanted;
    private TextField duration;

    public Traffic() {
        setTitle("Traffic Lights");
        Panel title = new Panel();
        title.add(new Label("Savanna Traffic Light Simulation"));
        add("North", title);
        
        area = new Canvas();
        add("Center", area);
        
        Panel buttons = new Panel();
        buttons.add(new Button("Start"));
        Choice c = new Choice();
        c.addItem("Red");
        c.addItem("Yellow");
        c.addItem("Green");
        c.addItem("Walk");
        buttons.add(c);
        buttons.add(new Label("Duration"));
        duration = new TextField("",3);
        duration.setEditable(false);
        buttons.add(duration);
        buttons.add(new Button("Walk"));
        buttons.add(new Button("Close"));
        add("South", buttons);        
    }
    
    public boolean mouseDown(Event evt, int x, int y) {
        setWanted = x/lightsWidth;
        return true;
    }
    
    public boolean action(Event evt, Object arg) {
        if(arg.equals("Start")) {
            lights[lightsNo] = new SetOfLights(area, lightsPosition);
            lights[lightsNo].start();
            lightsPosition += lightsWidth;
            lightsNo++;
        }
        else if(arg.equals("Walk"))
            lights[setWanted].walk = true;
        else if(arg.equals("Close")) {
            this.hide();
            this.dispose();
            System.exit(0);            
        }else return super.action(evt, arg);        
        return true;
    }

    public boolean handleEvent(Event evt) {
        if( evt.id == Event.WINDOW_DESTROY)
            System.exit(0);
        return super.handleEvent(evt);
    }
    
    public static void main(String[] args) {
        Frame f = new Traffic();
        f.resize(450,210);
        f.show();
    }    
}