#include <Servo.h>
Servo servoLeft;
Servo servoRight;

void setup()                                 // Built-in initialization block
{
  tone(4, 3000, 1000);                       // Play tone for 1 second
  delay(1000);                               // Delay to finish tone
  pinMode(10, INPUT);
  pinMode(9, OUTPUT);   // Left IR LED & Receiver

  pinMode(2, OUTPUT);
  pinMode(3, INPUT);
  Serial.begin(9600);

  servoLeft.attach(13);
  servoRight.attach(12);
}

void loop()                                  // Main loop auto-repeats
{
  int irRight = irDetect(2, 3, 38000);
  int irLeft = irDetect(9,10, 38000);
  Serial.println(irLeft, irRight);
  delay(100);

  if (irLeft == 0 && irRight == 0) { // if IR LED/RECEIVER detects both sides
  servoLeft.writeMicroseconds(1300); // Left wheel clockwise
  servoRight.writeMicroseconds(1300); // Right wheel clockwise

  }

  else if (irLeft == 1 && irRight == 0){ //Right IR detected, Left IR not detected
  servoLeft.writeMicroseconds(1300); // Left wheel cclockwise

 }
  else if (irLeft == 0 && irRight == 1){ //Right IR not detected, Left IR detected
 servoRight.writeMicroseconds(1300); // Right wheel clockwise

 }
 else if (irLeft == 1 && irRight == 1) { // if both receivers detect nothing
   servoRight.writeMicroseconds(1700); //reverse left wheel
   servoLeft.writeMicroseconds(1700); //reverse right wheel
}
}

int irDetect (int irLedPin, int irReceiverPin, long frequency) {
  tone(irLedPin , frequency, 8);
  delay(1);
  int ir = digitalRead(irReceiverPin);
  delay(1);
  return ir;
}