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

RTC_DS3231 rtc;

char daysOfTheWeek[7][12] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};

void setup() {
  Serial.begin(57600);

  #ifndef ESP8266
    while (!Serial); // tunggu koneksi port serial. Diperlukan untuk USB asli
  #endif

  if (!rtc.begin()) {
    Serial.println("Tidak dapat menemukan RTC");
    Serial.flush();
    while (1) delay(10);
  }

  if (rtc.lostPower()) {
  rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
    
  }

}

void loop() {
  DateTime now = rtc.now();

  Serial.print(now.year(), DEC);
  Serial.print('/');
  Serial.print(now.month(), DEC);
  Serial.print('/');
  Serial.print(now.day(), DEC);
  Serial.print(" (");
  Serial.print(daysOfTheWeek[now.dayOfTheWeek()]);
  Serial.print(") ");
  Serial.print(now.hour(), DEC);
  Serial.print(':');
  Serial.print(now.minute(), DEC);
  Serial.print(':');
  Serial.print(now.second(), DEC);
  Serial.println();

  Serial.print(" since midnight 1/1/1970 = ");
  Serial.print(now.unixtime());
  Serial.print("s = ");
  Serial.print(now.unixtime() / 86400L);
  Serial.println("d");

  // hitung tanggal yang akan datang 7 hari, 12 jam, 30 menit, 6 detik ke depan
  DateTime future (now + TimeSpan(7,12,30,6));

  Serial.print(" now + 7d + 12h + 30m + 6s: ");
  Serial.print(future.year(), DEC);
  Serial.print('/');
  Serial.print(future.month(), DEC);
  Serial.print('/');
  Serial.print(future.day(), DEC);
  Serial.print(' ');
  Serial.print(future.hour(), DEC);
  Serial.print(':');
  Serial.print(future.minute(), DEC);
  Serial.print(':');
  Serial.print(future.second(), DEC);
  Serial.println();

  Serial.print("Temperature: ");
  Serial.print(rtc.getTemperature());
  Serial.println(" C");

  Serial.println();
  delay(3000);
}