// linebot2.nqc
//	turn by reversing one tread

// sensor and motors
#define EYE		SENSOR_2
#define LEFT	OUT_A
#define RIGHT	OUT_C

// thresholds
#define LEFT_THRESHOLD  42
#define RIGHT_THRESHOLD 53

#define STRAIGHT_TIME 10

task main()
{
	SetSensor(EYE, SENSOR_LIGHT);
	On(LEFT+RIGHT);

	while(true)
	{
		if (EYE <= LEFT_THRESHOLD)
		{
			Rev(LEFT);
			until(EYE > LEFT_THRESHOLD);
			Fwd(LEFT);
			Wait(STRAIGHT_TIME);
		}
		else if (EYE >= RIGHT_THRESHOLD)
		{
			Rev(RIGHT);
			until(EYE < RIGHT_THRESHOLD);
			Fwd(RIGHT);
			Wait(STRAIGHT_TIME);
		}
	}
}