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

RTC_DS3231 rtc;
LiquidCrystal_I2C lcd(0x27, 20, 4);  // Set the LCD I2C address to 0x27 for a 20 chars and 4 line display

char t[40];  // Increased the size to accommodate the additional characters for the day of the week
float temperature;

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

  lcd.begin(20, 4);  // Initialize the LCD display with 20 columns and 4 rows
  lcd.backlight();

  rtc.begin();
  rtc.adjust(DateTime(2024, 4, 3, 17, 35, 56)); // Set the desired date and time
}

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

  sprintf(t, "%02d:%02d:%02d %02d/%02d/%02d ",  now.hour(), now.minute(), now.second(), now.day(), now.month(), now.year());  

  // Add the day of the week to the string
  strcat(t, getDayOfWeek(now.dayOfTheWeek()));

  lcd.setCursor(0, 0);
  lcd.print("Date/Time: ");
  lcd.setCursor(0, 1);
  lcd.print(t);

  temperature = rtc.getTemperature();
  lcd.setCursor(0, 2);
  lcd.print("Temperature: ");
  lcd.print(temperature);
  lcd.print(" C");
  lcd.setCursor(0, 3);
        delay(1000);
}

// Function to get the day of the week as a string
const char* getDayOfWeek(int d) {
  switch(d) {
    case 0: return "Sun";
    case 1: return "Mon";
    case 2: return "Tue";
    case 3: return "Wed";
    case 4: return "Thu";
    case 5: return "Fri";
    case 6: return "Sat";
    default: return "Error";
  }
}