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

public class BallField extends Canvas {

    private BufferStrategy bufferStrategy;
    private int DOUBLE_BUFFER = 2;
    private int PAGE_FLIP = 3;

    private java.util.List balls;
    private java.util.Timer timer;

    private int width;
    private int height;

    public BallField(){
        initFrame();

        try{
            createBufferStrategy(DOUBLE_BUFFER);
//            createBufferStrategy(PAGE_FLIP);
            bufferStrategy = getBufferStrategy();
        }catch(IllegalStateException ex){
            ex.printStackTrace();
            System.exit(0);
        }

        balls = new java.util.ArrayList();
        balls.add(new Ball(width, height));

        timer = new java.util.Timer();
        timer.schedule(new java.util.TimerTask(){
            public void run(){
                draw();
            }
        }, 1000, 60);
    }

    public void addBall(){
        balls.add(new Ball(width, height));
    }

    public void changeBallDirection(){
        for(int i = 0 ; i < balls.size() ; i++){
            ((Ball)balls.get(i)).turn();
        }
    }

    private void initFrame(){
        Frame frame = new Frame("Ball Field");
        frame.setIgnoreRepaint(true);
        frame.setBounds(100, 100, 600, 600);
        frame.addWindowListener(new WindowAdapter(){
            public void windowClosing(WindowEvent event){
                System.exit(0);
            }
        });

        frame.add(this, BorderLayout.CENTER);

        Button increaseButton = new Button("Ball Increase");
        increaseButton.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent event){
                addBall();
            }
        });
        
        Button directionButton = new Button("Ball Direction Change");
        directionButton.addActionListener(new ActionListener(){
                public void actionPerformed(ActionEvent event){
                    changeBallDirection();
                }
            });
        
        Button finishButton = new Button("Finish");
        finishButton.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent event){
                System.exit(0);
            }
        });
        
        Panel panel = new Panel();
        panel.setBackground(Color.lightGray);
        panel.add(increaseButton);
        panel.add(directionButton);
        panel.add(finishButton);
        
        frame.add(panel, BorderLayout.SOUTH);

        frame.setVisible(true);

        Dimension dim = getSize();
        width = dim.width;
        height = dim.height;
    }

    private void clear(Graphics2D g){
        g.setPaint(Color.white);
        g.fillRect(0, 0, width, height);
    }

    public void draw(){
        for(int i = 0 ; i < balls.size() ; i++){
            ((Ball)balls.get(i)).move();
        }

        Graphics2D g = (Graphics2D)bufferStrategy.getDrawGraphics();
        if(!bufferStrategy.contentsLost()){
            clear(g);
            for(int i = 0 ; i < balls.size() ; i++){
                ((Ball)balls.get(i)).drawShadow(g);
            }
            
            for(int i = 0 ; i < balls.size() ; i++){
                ((Ball)balls.get(i)).draw(g);
            }
            bufferStrategy.show();
            g.dispose();
        }
    }

    public static void main(String[] args){
        BallField field = new BallField();
    }
}