// Define GPIO pins for IR sensors
const int IR_SENSOR_PIN_1 = 2;
const int IR_SENSOR_PIN_2 = 3;

// Define GPIO pins for Signal S1 LEDs
const int S1_RED_LED_PIN = 4;
const int S1_YELLOW_LED_PIN = 5;
const int S1_GREEN_LED_PIN = 6;

// Define GPIO pins for Signal S2 LEDs
const int S2_RED_LED_PIN = 7;
const int S2_YELLOW_LED_PIN = 8;
const int S2_GREEN_LED_PIN = 9;

// Initialize GPIO pins for IR sensors and LEDs
void setup() {
  pinMode(IR_SENSOR_PIN_1, INPUT);
  pinMode(IR_SENSOR_PIN_2, INPUT);
  
  pinMode(S1_RED_LED_PIN, OUTPUT);
  pinMode(S1_YELLOW_LED_PIN, OUTPUT);
  pinMode(S1_GREEN_LED_PIN, OUTPUT);
  
  pinMode(S2_RED_LED_PIN, OUTPUT);
  pinMode(S2_YELLOW_LED_PIN, OUTPUT);
  pinMode(S2_GREEN_LED_PIN, OUTPUT);
}

// Function to control the traffic lights based on density
void controlTrafficLights(int density) {
  if (density == 10) {
    digitalWrite(S1_GREEN_LED_PIN, HIGH);
    digitalWrite(S1_YELLOW_LED_PIN, LOW);
    digitalWrite(S1_RED_LED_PIN, LOW);
    digitalWrite(S2_GREEN_LED_PIN, LOW);
    digitalWrite(S2_YELLOW_LED_PIN, HIGH);
    digitalWrite(S2_RED_LED_PIN, HIGH);
    delay(40000);
    digitalWrite(S2_YELLOW_LED_PIN, LOW);
    delay(5000);
    digitalWrite(S1_RED_LED_PIN, HIGH);
    digitalWrite(S1_GREEN_LED_PIN, LOW);
    delay(45000);
  } else if (density == 20) {
    digitalWrite(S1_GREEN_LED_PIN, HIGH);
    digitalWrite(S1_YELLOW_LED_PIN, LOW);
    digitalWrite(S1_RED_LED_PIN, LOW);
    digitalWrite(S2_GREEN_LED_PIN, LOW);
    digitalWrite(S2_YELLOW_LED_PIN, HIGH);
    digitalWrite(S2_RED_LED_PIN, HIGH);
    delay(50000);
    digitalWrite(S2_YELLOW_LED_PIN, LOW);
    delay(5000);
    digitalWrite(S1_RED_LED_PIN, HIGH);
    digitalWrite(S1_GREEN_LED_PIN, LOW);
    delay(55000);
  } else {
    // Default behavior
    digitalWrite(S1_GREEN_LED_PIN, HIGH);
    digitalWrite(S1_YELLOW_LED_PIN, LOW);
    digitalWrite(S1_RED_LED_PIN, LOW);
    digitalWrite(S2_GREEN_LED_PIN, LOW);
    digitalWrite(S2_YELLOW_LED_PIN, HIGH);
    digitalWrite(S2_RED_LED_PIN, HIGH);
  }
}

void loop() {
  // Read IR sensor values and calculate density
  int irSensor1Value = HIGH;
  int irSensor2Value = LOW;
  int density = irSensor1Value + irSensor2Value;
  
  // Control traffic lights based on density
  controlTrafficLights(density);
}