// Pin numbers are defined by the corresponding LED colors
#define RED_PIN 8
#define YELLOW_PIN 10
#define GREEN_PIN 12

// Define the delays for each traffic light color
int red_on = 6000;    // 6 s delay
int yellow_on=5000; // 3 s delay
int yellow_blink = 500;  // 0.5 s delay
int green_on = 6000;
// Declaring the timer function to count 1 ms of delay instead of calling the delay function
int delay_timer(int milliseconds) {
  int count = 0;
  while(1) {
    if(TCNT0 >= 16) {  // Checking if 1 millisecond has passed
      TCNT0 = 0;
      count++;
    }
    if (count == milliseconds) {  // Checking if required milliseconds delay has passed
      break;  // Exit the loop
    }
  }
  return 0;
}

void setup() {
  // Define pins connected to LEDs as outputs
  pinMode(RED_PIN, OUTPUT);
  pinMode(YELLOW_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
  
  // Set up the Timer
  TCCR0A = 0b00000000; // Timer/Counter Control Register A
  TCCR0B = 0b00000101; // Timer/Counter Control Register B (setting pre-scaler for timer clock)
  TCNT0 = 0; // Initialize Timer/Counter register to 0
}

void loop() {
  // Turn on the green LED
  digitalWrite(RED_PIN, HIGH);
  delay_timer(red_on); // Delay for green light
  
  // Turn off the green LED
  digitalWrite(RED_PIN, LOW);
   digitalWrite(YELLOW_PIN, HIGH);
   delay_timer(yellow_on);
   digitalWrite(YELLOW_PIN, LOW);
  
  // Blink the yellow LED 4 times
  for(int i = 0; i < 4; i++) {
    digitalWrite(YELLOW_PIN, HIGH);
    delay_timer(yellow_blink);
    digitalWrite(YELLOW_PIN, LOW);
    delay_timer(yellow_blink);
  }
  
  // Turn on the red LED
  digitalWrite(GREEN_PIN, HIGH);
  delay_timer(green_on); // Delay for red light
  
  // Turn off the red LED
  digitalWrite(GREEN_PIN, LOW);
}