const int gasSensorA1Pin = A0;  // Analog input pin for sensor A1
const int gasSensorA2Pin = A1;  // Analog input pin for sensor A2
const int heaterH1Pin = 2;      // Digital pin for heater H1
const int heaterH2Pin = 3;      // Digital pin for heater H2
const int buzzerPin = 4;        // Digital pin for the buzzer
const int ledA1Pin = 5;         // Digital pin for LED corresponding to sensor A1
const int ledA2Pin = 6;         // Digital pin for LED corresponding to sensor A2

int threshold = 1022;  // Adjust this threshold value based on your sensor and gas type

void setup() {
  pinMode(heaterH1Pin, OUTPUT);
  pinMode(heaterH2Pin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(ledA1Pin, OUTPUT);
  pinMode(ledA2Pin, OUTPUT);
  Serial.begin(9600);  // Initialize serial communication for debugging (optional)
}

void loop() {
  // Turn on heater for sensor A1
  digitalWrite(heaterH1Pin, HIGH);
  delay(3000);  // Allow time for the sensor to stabilize (adjust as needed)

  int gasValueA1 = analogRead(gasSensorA1Pin);  // Read sensor A1
  Serial.print("Gas Value A1: ");
  Serial.println(gasValueA1);

  // Turn on heater for sensor A2
  digitalWrite(heaterH2Pin, HIGH);
  delay(3000);  // Allow time for the sensor to stabilize (adjust as needed)

  int gasValueA2 = analogRead(gasSensorA2Pin);  // Read sensor A2
  Serial.print("Gas Value A2: ");
  Serial.println(gasValueA2);

  // Turn off heaters
  digitalWrite(heaterH1Pin, LOW);
  digitalWrite(heaterH2Pin, LOW);

  if (gasValueA1 > threshold || gasValueA2 > threshold) {
    // Gas detected, trigger the buzzer and turn on LEDs
    digitalWrite(buzzerPin, HIGH);
    digitalWrite(ledA1Pin, HIGH); // Turn on LED for sensor A1
    digitalWrite(ledA2Pin, HIGH); // Turn on LED for sensor A2
    Serial.println("Gas detected! Alarm activated");
    delay(10000);  // Buzzer activates for 1 second
    digitalWrite(buzzerPin, LOW);
    digitalWrite(ledA1Pin, LOW); // Turn off LED for sensor A1
    digitalWrite(ledA2Pin, LOW); // Turn off LED for sensor A2
    delay(2000);  // Wait for a moment before checking again
  } else {
    // No gas detected, turn off the buzzer and LEDs
    digitalWrite(buzzerPin, LOW);
    digitalWrite(ledA1Pin, LOW); // Turn off LED for sensor A1
    digitalWrite(ledA2Pin, LOW); // Turn off LED for sensor A2
    delay(2000);  // Wait for a moment before checking again
  }
}