#include <Wire.h>
#include <RTClib.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

#define OLED_RESET    -1
#define SCREEN_ADDRESS 0x3C

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

RTC_DS3231 rtc;

void setup() {
  Serial.begin(9600);

  if (!rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }

  if (rtc.lostPower()) {
    Serial.println("RTC lost power, let's set the time!");
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }

  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }

  display.display();
  delay(2000);
  display.clearDisplay();
}

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

  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println("Current Time:");
  display.setTextSize(2);
  display.setCursor(5, 10);
  display.print(now.hour(), DEC);
  display.print(':');
  if (now.minute() < 10) {
    display.print('0');
  }
  display.print(now.minute(), DEC);
  display.print(':');
  if (now.second() < 10) {
    display.print('0');
  }
  display.println(now.second(), DEC);
  display.setTextSize(1);
  display.setCursor(0, 33);
  display.println("Current Date:");
  display.setTextSize(2);
  display.setCursor(5, 45);
  display.print(now.day(), DEC);
  display.print('/');
  display.print(now.month(), DEC);
  display.print('/');
  display.println(now.year(), DEC);
  display.display();
  delay(1000);
}