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

RTC_DS1307 rtc;
LiquidCrystal_I2C lcd(0x27, 20, 4);

void setup() {
  Wire.begin();
  rtc.begin();
  lcd.init();
  lcd.backlight();

  // Uncomment the following line to set the time only once during setup.
  // rtc.adjust(DateTime(__DATE__, __TIME__));
  Serial.begin(9600);
  Serial.println("RTC Initialized.");
}

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

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Time: ");
  lcd.print(formatTime(now.hour(), false)); // Display in 12-hour format with AM/PM
  lcd.print(':');
  lcd.print(now.minute(), DEC);
  lcd.print(':');
  lcd.print(now.second(), DEC);
  lcd.print(" ");
  lcd.print(getAMPM(now.hour())); // Display AM or PM

  lcd.setCursor(0, 1);
  lcd.print("Date: ");
  lcd.print(now.day(), DEC);
  lcd.print('/');
  lcd.print(now.month(), DEC);
  lcd.print('/');
  lcd.print(now.year(), DEC);

  //Uncomment These Lines If you want it to display the time in the "Console"

  //Serial.print("Current Date/Time: ");
  //Serial.print(now.year(), DEC);
  //Serial.print('/');
  //Serial.print(now.month(), DEC);
  //Serial.print('/');
  //Serial.print(now.day(), DEC);
  //Serial.print(' ');
  //Serial.print(formatTime(now.hour(), false)); // Display in 12-hour format with AM/PM
  //Serial.print(':');
  //Serial.print(now.minute(), DEC);
  //Serial.print(':');
  //Serial.print(now.second(), DEC);
  //Serial.print(" ");
  //Serial.print(getAMPM(now.hour())); // Display AM or PM
  //Serial.println();

  delay(690); // Update Every 0.69 Seconds.
}

String formatTime(int hours, bool leadingZero) {
  if (hours == 0) {
    return (leadingZero ? "12" : " 12");
  } else if (hours > 0 && hours <= 9) {
    return (leadingZero ? "0" : " ") + String(hours);
  } else if (hours >= 10 && hours <= 12) {
    return String(hours);
  } else {
    return (leadingZero ? "0" : " ") + String(hours - 12);
  }
}

String getAMPM(int hours) {
  return (hours >= 12) ? "PM" : "AM";
}