#include <Arduino.h>
#include <Wire.h>
#include <Adafruit_GFX.h>

// Pin definitions
//const int MQ2_PIN = 34;       // Analog input for MQ-2 sensor
const int BUZZER_PIN = 13;    // Digital output for buzzer
const int RELAY_PIN = 12;     // Digital output for relay driver


const int GAS_THRESHOLD = 1000;
const int gasValue = 500;  // Fixed gas value for demonstration

void setup() {
  Serial.begin(115200);
  
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(RELAY_PIN, OUTPUT);
  
  digitalWrite(BUZZER_PIN, LOW);
  digitalWrite(RELAY_PIN, HIGH);  // Relay ON initially
  
  Serial.println("Gas detection system initialized");
}

void loop() {
  if (gasValue > GAS_THRESHOLD) {
    // Gas detected
    digitalWrite(RELAY_PIN, LOW);  // Turn OFF relay
    digitalWrite(BUZZER_PIN, HIGH);
    Serial.println("Gas detected! LED turned ON");
  } else {
    // No gas detected
    digitalWrite(RELAY_PIN, HIGH);  // Turn ON relay
    digitalWrite(BUZZER_PIN, LOW);
    Serial.println("No gas detected. LED turned OFF");
  }
  
  delay(1000);
}