#include <DHT.h>

#define GAS_SENSOR 7     // Digital pin for Gas Sensor
#define DHTPIN 2         // Digital pin for DHT11
#define PIR_SENSOR 3     // Digital pin for PIR Sensor
#define BUZZER 4         // Digital pin for Buzzer
#define FIRE_LED 5       // Red LED for Fire Alert
#define SAFE_LED 6       // Green LED for Safe Status

#define DHTTYPE DHT11
DHT dht(DHTPIN, DHTTYPE);

const float tempThreshold = 34.0; // Temperature threshold in °C

void setup() {
    Serial.begin(9600);
    pinMode(GAS_SENSOR, INPUT);
    pinMode(PIR_SENSOR, INPUT);
    pinMode(BUZZER, OUTPUT);
    pinMode(FIRE_LED, OUTPUT);
    pinMode(SAFE_LED, OUTPUT);
    dht.begin();
}

void loop() {
    bool smokeDetected = digitalRead(GAS_SENSOR); // HIGH if smoke detected
    bool flameDetected = digitalRead(PIR_SENSOR); // HIGH if flame detected
    float temp = dht.readTemperature();
    bool tempUnstable = temp > tempThreshold;

    Serial.println("Monitoring...");

    if (smokeDetected && flameDetected) {
        Serial.println("ALERT: Flame and Smoke Detected!");
    } else if (smokeDetected) {
        Serial.println("ALERT: Smoke Detected!");
    } else if (flameDetected) {
        Serial.println("ALERT: Flame Detected!");
    }

    if (tempUnstable) {
        Serial.println("WARNING: Temperature is Unstable!");
    }

    if (smokeDetected || flameDetected || tempUnstable) {
        digitalWrite(BUZZER, HIGH);
        digitalWrite(FIRE_LED, HIGH);
        digitalWrite(SAFE_LED, LOW);
    } else {
        Serial.println("System Normal.");
        digitalWrite(BUZZER, LOW);
        digitalWrite(FIRE_LED, LOW);
        digitalWrite(SAFE_LED, HIGH);
    }

    Serial.println("------------------------");
    delay(1000);
}