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

LiquidCrystal_I2C lcd(0x27,20,4);
RTC_DS1307 rtc;
int sec=1;
int mins=0;
int hour=0;
const float BETA=3950;


void setup(){
  if(!rtc.begin()){
    abort();
  }
  lcd.init();
  lcd.backlight();
  lcd.setCursor(6,1);
  lcd.print("00:00:00");
  lcd.setCursor(1,2);
  lcd.print("Temperatura ");
  tone(13,1200,50);
  delay(150);
  tone(13,1400,50);
}

void loop(){
    DateTime now=rtc.now();
    lcd.setCursor(5,0);
    if(10>now.day())
    {
      lcd.print(' ');
      lcd.print(now.day());
    }else lcd.print(now.day());
    lcd.print('/');
    if(10>now.month()){
      lcd.print(' ');
      lcd.print(now.month());
    }else lcd.print(now.month());
    lcd.print('/');
    lcd.print(now.year());
    lcd.setCursor(8,1);
    lcd.print(" ");
    lcd.setCursor(11,1);
    lcd.print(" ");
    delay(500);
    lcd.backlight();
    lcd.setCursor(11,1);
    lcd.print(":");
    lcd.setCursor(8,1);
    lcd.print(":");

    if(10>now.second()){
      lcd.setCursor(12,1);
      lcd.print("0");
      lcd.setCursor(13,1);
      lcd.print(now.second());
    }else{
      lcd.setCursor(12,1);
      lcd.print(now.second());
    }

    if(10>now.minute()){
      lcd.setCursor(9,1);
      lcd.print("0");
      lcd.setCursor(10,1);
      lcd.print(now.minute());
    }else{
      lcd.setCursor(9,1);
      lcd.print(now.minute());
    }

    if(10>now.hour()){
      lcd.setCursor(6,1);
      lcd.print("0");
      lcd.setCursor(7,1);
      lcd.print(now.hour());
    }else{
      lcd.setCursor(6,1);
      lcd.print(now.hour());
    }
    int analogValue=analogRead(A0);
    float celsius=1/(log(1/(1023./analogValue-1))/BETA+1.0/298.15)-273.15;
    int temp=(int)celsius;
    
    if(10>temp && 0<=temp){
      lcd.setCursor(14,2);
      lcd.print("  ");
      lcd.setCursor(16,2);
      lcd.print(temp);
    }else if(10<=temp){
      lcd.setCursor(14,2);
      lcd.print(" ");
      lcd.print(temp);
    }
  if(0>temp && -10<temp){
    lcd.setCursor(14,2);
    lcd.print(" ");
    lcd.setCursor(15,2);
    lcd.print(temp);
  }else if(-10>=temp){
    lcd.setCursor(14,2);
    lcd.print(temp);
  }

    lcd.setCursor(17,2);
    lcd.print((char)223);
    lcd.print("C");

    delay(500);
}