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

// Initialize the LCD, adjust the I2C address (0x27 is common for LCD2004)
LiquidCrystal_I2C lcd(0x27, 20, 4);

// Define DHT22 sensor settings
#define DHTPIN 13      // DHT22 data pin connected to GPIO 13
#define DHTTYPE DHT22  // DHT22 (AM2302) sensor type
DHT dht(DHTPIN, DHTTYPE);

// Initialize the DS1307 RTC
RTC_DS1307 rtc;

void setup() {
  // Initialize the LCD
  lcd.init();
  lcd.backlight();
  
  // Initialize DHT22 sensor
  dht.begin();

  // Initialize DS1307 RTC
  if (!rtc.begin()) {
    lcd.setCursor(0, 0);
    lcd.print("Couldn't find RTC");
    while (1);  // Halt if RTC is not found
  }
  
  if (!rtc.isrunning()) {
    lcd.setCursor(0, 0);
    lcd.print("RTC is not running");
    // Uncomment the next line to set the RTC to the current time
    // rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }

  // Initial message
  lcd.setCursor(0, 0);
  lcd.print("Temp & Humidity");
  delay(2000);
}

void loop() {
  // Read temperature and humidity from DHT22
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  // Check if any readings failed and exit early
  if (isnan(humidity) || isnan(temperature)) {
    lcd.setCursor(0, 0);
    lcd.print("Error reading data");
    return;
  }

  // Get current date and time from RTC
  DateTime now = rtc.now();

  // Display date and time on the LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print(now.day(), DEC);
  lcd.print('/');
  lcd.print(now.month(), DEC);
  lcd.print('/');
  lcd.print(now.year(), DEC);
  
  lcd.setCursor(0, 1);
  lcd.print(now.hour(), DEC);
  lcd.print(':');
  lcd.print(now.minute(), DEC);
  lcd.print(':');
  lcd.print(now.second(), DEC);

  // Display temperature on the third line
  lcd.setCursor(0, 2);
  lcd.print("Temp: ");
  lcd.print(temperature);
  lcd.print(" C");

  // Display humidity on the fourth line
  lcd.setCursor(0, 3);
  lcd.print("Humidity: ");
  lcd.print(humidity);
  lcd.print(" %");

  // Wait before updating again
  delay(2000);
}