#include <DHT.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

#define DHTPIN 2      // Digital pin connected to the DHT sensor
#define DHTTYPE DHT22 // DHT 22 (AM2302)

#define ldrPin A0     // Analog pin connected to the photoresistor
#define ledPin 13     // Digital pin connected to the LED
#define buzzerPin 11  // Digital pin connected to the buzzer

#define I2C_ADDR    0x27 // I2C address for the LCD1602
#define BACKLIGHT_PIN 3
#define En_pin 2
#define Rw_pin 1
#define Rs_pin 0
#define D4_pin 4
#define D5_pin 5
#define D6_pin 6
#define D7_pin 7

LiquidCrystal_I2C lcd(I2C_ADDR, 16, 2); // Initialize the LCD1602 with 16 columns and 2 rows

DHT dht(DHTPIN, DHTTYPE); // Initialize DHT sensor

void setup() {
  Serial.begin(9600);
  lcd.begin (16,2);  // Initialize the LCD with 16 columns and 2 rows
  lcd.setBacklight(HIGH);
  pinMode(ledPin, OUTPUT);    // Set LED pin as output
  pinMode(buzzerPin, OUTPUT); // Set buzzer pin as output
  dht.begin();                // Initialize DHT sensor

  // Print initial messages to the LCD
  lcd.clear();
  lcd.print("Fire Detection");
  lcd.setCursor(0, 1);
  lcd.print("System");
  delay(2000);
  lcd.clear();
}

void loop() {
  // Read temperature, humidity, and LDR value
  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();
  int ldrValue = analogRead(ldrPin);

  // Print temperature, humidity, and LDR value to serial monitor
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");
  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");
  Serial.print("LDR Value: ");
  Serial.println(ldrValue);

  // Print temperature, humidity, and LDR value to LCD
  lcd.clear();
  lcd.print("Temp: ");
  lcd.print(temperature);
  lcd.print(" C");
  lcd.setCursor(0, 1);
  lcd.print("Humidity: ");
  lcd.print(humidity);
  lcd.print(" %");

  // Fire detection logic
  if (temperature > 50 && ldrValue < 50 && humidity > 10) { // Adjust threshold values as needed
    Serial.println("Fire detected!");
    lcd.clear();
    lcd.print("Fire Detected!");
    digitalWrite(ledPin, HIGH);   // Turn on LED
    tone(buzzerPin, 1000);        // Turn on buzzer
    delay(1000);                  // Delay for 1 second
    digitalWrite(ledPin, LOW);    // Turn off LED
    noTone(buzzerPin);            // Turn off buzzer
    delay(1000);                  // Delay for 1 second
  }

  delay(1000); // Delay for readability
}