#include <LiquidCrystal.h>

// Define sensor pins
#define MQ2_PIN     PA0
#define LDR_PIN     PA1
#define BUZZER_PIN  PB0
#define GAS_LED     PB1
#define FIRE_LED    PC13

#define GAS_THRESHOLD 900
#define LDR_THRESHOLD 512

// LCD pins: RS, EN, D4, D5, D6, D7 (you can connect accordingly)
LiquidCrystal lcd(PA2, PA3, PA4, PA5, PA6, PA7); // Adjust pins as per your Wokwi wiring

void setup() {
  pinMode(GAS_LED, OUTPUT);
  pinMode(FIRE_LED, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  Serial.begin(9600);
  
  lcd.begin(16, 2);
  lcd.print("System Initializing");
  delay(2000);
  lcd.clear();
}

void loop() {
  int gasValue = analogRead(MQ2_PIN);    
  int ldrValue = analogRead(LDR_PIN);    

  Serial.print("Gas Sensor Value: ");
  Serial.print(gasValue);
  Serial.print(" | LDR Value: ");
  Serial.println(ldrValue);

  bool gasDetected = gasValue > GAS_THRESHOLD;
  bool fireDetected = ldrValue < LDR_THRESHOLD;

  digitalWrite(GAS_LED, gasDetected ? HIGH : LOW);
  digitalWrite(FIRE_LED, fireDetected ? HIGH : LOW);

  lcd.clear();

  if (gasDetected && fireDetected) {
    lcd.print("Gas & Fire Alert!");
    tone(BUZZER_PIN, 1000);
  } else if (gasDetected) {
    lcd.print("Gas Detected!");
    tone(BUZZER_PIN, 1000);
  } else if (fireDetected) {
    lcd.print("Fire Detected!");
    tone(BUZZER_PIN, 1000);
  } else {
    lcd.print("All Safe");
    noTone(BUZZER_PIN);
  }

  delay(500);
}