/* metasesns.c */
/* requires turtle.c, timer.c, avoid.c */
void random_avoid()
{
    backward(); sleep(.4);
    set_beeper_pitch(1000.); beeper_on();
    if (random(2) == 0) left();
    else right();
    sleep((float)random(100)/100. + .5);
    beeper_off();
}

void left_avoid()
{
    backward(); sleep(.4);
    right(); sleep(.4);
}

void right_avoid()
{
    backward(); sleep(.4);
    left(); sleep(.4);
} 

int LEFT_MOTOR= 0;
int RIGHT_MOTOR= 3;

void forward()
{
    fd(LEFT_MOTOR);
    fd(RIGHT_MOTOR);
}

void backward()
{
    bk(LEFT_MOTOR);
    bk(RIGHT_MOTOR);
}

void right()
{
    fd(LEFT_MOTOR);
    bk(RIGHT_MOTOR);
}

void left()
{
    fd(RIGHT_MOTOR);
    bk(LEFT_MOTOR);
}

void stop()
{
    off(LEFT_MOTOR);
    off(RIGHT_MOTOR);
}

/* timer.c */
float _timer;

void reset_timer() 
{
    _timer= seconds();
}

float timer()
{
    return seconds() - _timer;
}

int LEFT_TOUCH= 14;
int RIGHT_TOUCH= 13;

void main() 
{
    int recent_bumps= 0;
    reset_timer();
    
    while (1) 
      {
        forward();
        if (digital (LEFT_TOUCH)) 
          {
            if (timer() < 2.)    /* last bump reset? */
              {                       
                if (recent_bumps == 5)   /* yes; many recent? */
                  {         
                    random_avoid();  /* yes; perform avoid */
                    reset_timer();
                    recent_bumps= 0;
                }  else {   /* normal avoid, increment, and reset */
                    left_avoid();
                    reset_timer();
                    recent_bumps++;
                }
            }else {    /* haven't bumped for a while */
                left_avoid();
                reset_timer();
                recent_bumps= 1;
            }
        }

    if (digital (RIGHT_TOUCH))
      {
        if (timer() < 2.)    /* last bump recent? */
          {
            if (recent_bumps == 5)   /* yes; many recent? */
              {
                random_avoid();   /* yes; perform avoid */
                reset_timer();
                recent_bumps= 0;
            } else {      /* normal avoid, increment, and reset */
                
                right_avoid();
                reset_timer();
                recent_bumps++;
            }
        } else {
            
            right_avoid();
            reset_timer();
            recent_bumps= 1;
            
        }
    }
        
    }
}