import java.applet.* ;
import java.awt.* ;
import java.lang.*;
import java.util.Random;

public class vibora extends Applet implements Runnable {
  public Graphics g;
  public Button Iniciar,Pausa,rapido,lento;
  int x2,y2,vel,largo,xx,yy;
  int x[],y[];
  int avance;
  Random aleat;
  Thread hilo;
  Image aux;

public void azar() {
  boolean sale = false;
  int i;
  while (!sale) {
  xx = aleat.nextInt() % ((x2-10) / 10) * 10;
  yy = aleat.nextInt() % ((y2-30) / 10) * 10;
  if (xx < 0) xx*=-1;
  if (yy < 0) yy*=-1;
  System.out.println ("xx= " + xx + "  yy = " + yy);
  System.out.println ("Largo= " + largo);
  sale = true;
  for (i=0; i<largo; i++)
    if (xx == x[i] && yy+1 == y[i])
      sale = false;
  }
}

public void init () {
  int i,c=0;
  avance = 0;
  largo = 6;
  aleat = new Random();
  hilo = null;
  x= new int[800];
  y = new int[800];
  x2=getSize().width;
  y2=getSize().height;
  for (i=6; i>0; i--) {
    x[c]=i*10;
    y[c]=1;
    c++;
  }
  azar();
  vel=100;
  add(Iniciar=new Button("Iniciar"));
  add(Pausa=new Button("Pausa"));
  add(rapido=new Button("acelerar"));
  add(lento=new Button("alentar"));
  setBackground (Color.white);
  aux = createImage(x2,y2);
  g = aux.getGraphics();
}

public void start() {
  if (hilo == null) {
  hilo = new Thread (this);
  hilo.start();
  }
}

public void stop() {
  if (hilo != null) {
  hilo.stop();
  hilo=null;
  }
}

public void run() {
  int i;
  while (hilo!=null) {
     if (avance != 0) recorre();
      switch (avance){
        case 1: x[0]+=10;
        break;
        case 2: x[0]-=10;
        break;
        case 3: y[0]-=10;
        break;
        case 4: y[0]+=10;
        break;
    }
  if (x[0] == xx && y[0] == yy+1) {  // cuando come
     azar();
     x[largo+1] = x[largo] = x[largo-1];
     y[largo+1] = y[largo] = y[largo-1];
     largo += 2;
  }
  if (x[0]>x2-20) avance = 5 ;
  if (y[0]>y2-30) avance = 5 ;
  if (x[0]<0) avance = 5 ;
  if (y[0]<0) avance = 5 ;
  for (i=1; i<largo; i++)
    if (x[0] == x[i] && y[0] == y[i])
      avance = 5;
    repaint();
if (avance == 5) {
     stop();
   }
    try {
      Thread.sleep(vel);
    } catch (InterruptedException e) {}
    } // while
}

public void recorre() {
  int i;
  for (i=largo-1; i>0; i--) {
    x[i] = x[i-1];
    y[i] = y[i-1];
  }
}

public void paint (Graphics g) {
    int i;
    rapido.setLocation(10+x2/4*2,y2-25);
    lento.setLocation(10+x2/4*3,y2-25);
    Iniciar.setLocation(10,y2-25);
    Pausa.setLocation(10+x2/4,y2-25);
    g.drawRect(0,0,x2-10,y2-30+1);

  for (i=0; i<largo-1; i++) {
    if (x[i]==x[i+1] && y[i]>y[i+1])
         g.fillRect(x[i]+1,y[i]-3,8,12);
   if (x[i]==x[i+1] && y[i]<y[i+1])
         g.fillRect(x[i]+1,y[i]+1,8,12);
   if (y[i]==y[i+1] && x[i]>x[i+1])
         g.fillRect(x[i]-3,y[i]+1,12,8);
   if (y[i]==y[i+1] && x[i]<x[i+1])
         g.fillRect(x[i]+1,y[i]+1,12,8);
     }
  g.fillRect(x[largo-1]+1,y[largo-1]+1,8,8);
  g.setColor(Color.red);
  g.fillOval(xx+1,yy+2,6,6);
  if (avance == 5) {
    g.fillRect ((x2-100)/2,(y2-40)/2,100,40);
    g.setColor (Color.black);
    g.drawString("Fin de Juego",(x2-100)/2+17,(y2-40)/2+25 );//,"Ejele");
  }
  if (avance == 0) {
    g.fillRect ((x2-100)/2,(y2-40)/2,100,40);
    g.setColor (Color.black);
    g.drawString("Iniciar",(x2-100)/2+35,(y2-40)/2+25 );//,"Ejele");
  }
//  h.drawImage(aux,0,0,this);
//  aux = createImage(x2,y2);
//  g = aux.getGraphics();
}

public boolean handleEvent(Event e) {
//  System.out.println ("e.id = " + e.id);
if (e.id == 403 && avance!=5)
  switch (e.key) {
  case e.DOWN:
    if (avance != 3 )avance = 4;
    System.out.println ("Abajo");
    break;
  case e.UP:
    if (avance != 4 )avance = 3;
    System.out.println ("Arriba");
    break;
  case e.RIGHT:
    if (avance != 2 )avance = 1;
    System.out.println ("Derecha");
    break;
  case e.LEFT:
    if (avance != 1 )avance = 2;
    System.out.println ("Izquierda");
    break;
   }

    if (e.target == Pausa)
      if (e.id == 1001)
         stop();

    if (e.target == Iniciar)
      if (e.id == 1001) {
        System.out.println ("Avance = "+avance);
        if (avance == 5)
          init();
          stop();
          start();
        if (avance ==0)
          avance=1;
      }

    if (e.target == rapido)
      if (e.id == 1001)
         if (vel>10)
            vel-=10;

    if (e.target == lento)
      if (e.id == 1001)
            vel+=10;
//    repaint();
    return true;
  }
}