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

#define DHTPIN 2 
#define DHTTYPE DHT22   

LiquidCrystal_I2C lcd(0x27, 20, 4);
DHT dht(DHTPIN, DHTTYPE);
RTC_DS1307 rtc;

void setup() {
  Serial.begin(9600);
  
  if (!rtc.begin()) {
    Serial.println(F("Couldn't find RTC"));
    while (1);
  }
  
  if (!rtc.isrunning()) {
    Serial.println(F("RTC is NOT running, let's set the time!"));
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }
  
  lcd.init();
  lcd.backlight();
  dht.begin();
}

void loop() {
  // Wait a few seconds between measurements.
  delay(2000);

  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();

  if (isnan(temperature) || isnan(humidity)) {
    Serial.println(F("Failed to read from DHT sensor!"));
    return;
  }

  DateTime now = rtc.now();

  char time_buf[17]; 
  sprintf(time_buf, "%04u/%02u/%02u %02u:%02u:%02u", 
          now.year(), now.month(), now.day(), 
          now.hour(), now.minute(), now.second());

  // Display data on the LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print(F("Hum: "));
  lcd.print(humidity);
  lcd.setCursor(0, 1);
  lcd.print(F("Temp: "));
  lcd.print(temperature);
  // lcd.print((char)223); // Degree symbol
  // delay(3000); // Wait 3 seconds before the next update

  lcd.setCursor(0, 2);
  lcd.print(F("Date: "));
  lcd.print(now.year());
  lcd.print(F("/"));
  lcd.print(now.month());
  lcd.print(F("/"));
  lcd.print(now.day());
  lcd.setCursor(0, 3);
  // lcd.print(F("Time: "));
  lcd.print(time_buf);

  // Print data to Serial Monitor
  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.print("%, Temperature: ");
  Serial.print(temperature);
  Serial.print((char)223);
  Serial.print("C, ");
  Serial.print("Date: ");
  Serial.print(now.year());
  Serial.print("/");
  Serial.print(now.month());
  Serial.print("/");
  Serial.print(now.day());
  Serial.print(", Time: ");
  Serial.print(time_buf);
  Serial.println();

  delay(3000); // Wait 3 seconds before the next update
}