import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.Random;

public class Pong {

	private static final int X_SIZE = 600, Y_SIZE = 600;

    public static void main(String[ ] args) {
			JFrame frame = new JFrame("Graphics Skeleton");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setSize(X_SIZE, Y_SIZE);
            PongPanel panel = new PongPanel( );
            panel.setFocusable(true);
            frame.add(panel);
            frame.setVisible(true);
    }

   private static class PongPanel extends JPanel implements KeyListener, ActionListener {
	   private int p1y,p2y,p1d,p2d,bx,by,bdx,bdy, score1, score2, winner;
	   private Timer t;
	   private Random gen;
	   public PongPanel()
	   {
		   gen=new Random();
		   launch();		// launches the ball
		   score1=0;
		   winner=0;
		   score2=0;
		   p1y=280;		// start each paddle around the middle
		   p2y=280;
		   p1d=0;		// each paddle is stopped
		   p2d=0;
		   addKeyListener(this);
		   t=new Timer(10, this);
		   t.start();
	   }

	   public void launch()
	   {
		   bx=247;				// starting point for the ball in the x direction
		   by=gen.nextInt(400)+100;   // randomly generate starting point for ball in y direction
		   do{
		   	bdx=gen.nextInt(5)-2;
		   }while(bdx==0);
		   bdy=gen.nextInt(5)-2;
	   }

	   public void bounce()
	   {
	   	   bdx*=-1;
	   	   bdy=gen.nextInt(5)-2;
	   }

	   public boolean collide(int p, int bx, int by, int px, int py)
	   {
	   	   if(p==1&&(bx==px+1||bx==px+2||bx==px+3||bx==px+4)&&by-5>=py&&by+5<=py+30) return true;
	   	   if(p==2&&(bx==px-9||bx==px-8||bx==px-7||bx==px-6)&&by-5>=py&&by+5<=py+30) return true;
		   return false;
	   }

	   public void actionPerformed(ActionEvent e)
	   {
	   	   p1y+=p1d;
	   	   p2y+=p2d;
	   	   if(p1y<20||p1y>480) p1d=0;
	   	   if(p2y<20||p2y>480) p2d=0;
	   	   bx+=bdx;
	   	   by+=bdy;
	   	   if(by<20) {
	   	   	 bdy*=-1;
	   	   	 by=22;
	   	   }
	   	   if(by>480) {
	   	   	bdy*=-1;
	   	   	by=478;
	   	   }
	   	   if(collide(1,bx,by,20,p1y))
	   	   	  bounce();
	   	   if(collide(2,bx,by,480,p2y))
	   	   	  bounce();
	   	   if(bx<20)
	   	   {
	   	   	  score2++;
	   	   	  if(score2==10)
	   	   	  {
	   	   	  	winner=2;
	   	   	  	t.stop();
	   	   	  }
	   	   	  else launch();
	   	   }
	   	   if(bx>480)
	   	   {
	   	   	  score1++;
	   	   	  if(score1==10)
	   	   	  {
	   	   	  	winner=1;
	   	   	  	t.stop();
	   	   	  }
	   	   	  else launch();
	   	   }
		   repaint();
	   }

	   public void paintComponent(Graphics g)
	   {
		   super.paintComponent(g);
		   g.setColor(Color.black);
		   g.fillRect(0,0,X_SIZE,Y_SIZE);
		   g.setColor(Color.white);
		   g.fillOval(bx,by,10,10);
		   g.fillRect(20,p1y,5,30);
		   g.fillRect(480,p2y,5,30);
		   g.drawString("Player 1: " +score1+"     Player2: "+score2,200, 510);
		   if(winner==1)
		   	g.drawString("Player 1 wins!", 250,380);
		   else if(winner==2)
		   	g.drawString("Player 2 wins!", 250,380);
	   }

	   public void pause(Boolean b)
	   {
		   if(b) t.stop();
		   else if(!b) t.start();
	   }
	   public void keyPressed(KeyEvent e)
	   {
	   	   char c=e.getKeyChar();
	   	   if(c=='a')
	   	   {
	   	   	  p1d--;
	   	   	  if(p1d<-3) p1d=-3;
	   	   }
	   	   if(c=='z')
	   	   {
	   	   	  p1d++;
	   	   	  if(p1d>3) p1d=3;
	   	   }
	   	   if(c=='k')
	   	   {
	   	   	  p2d--;
	   	   	  if(p2d<-3) p2d=-3;
	   	   }
	   	   if(c=='m')
	   	   {
	   	   	  p2d++;
	   	   	  if(p2d>3) p2d=3;
	   	   }
	   	   
	   	   if(c=='p') pause(true);
	   	   if(c=='r') pause(false);
	   }

	   public void keyTyped(KeyEvent e) {}
	   public void keyReleased(KeyEvent e) {}
   }
}