#include <Wire.h>
#include <OneWire.h>
#include <TimerOne.h>
#include <LiquidCrystal_I2C.h>
#include <DallasTemperature.h>

#define ONE_WIRE_BUS 7
#define buttonPin 2

/*
  This sketch shows the current temperature, and pushing the button
  allows it to change from celsius to fahrenheit and vice-versa

  DS18B20 temperature sensor pin 7
  Pushbutton pin 2
*/

bool tempCelsius = true;
//initialize the liquid crystal library
//the first parameter is  the I2C address
//the second parameter is how many rows are on your screen
//the  third parameter is how many columns are on your screen
LiquidCrystal_I2C lcd(0x27,  20, 4);

// Setup a oneWire instance to communicate with any OneWire device
OneWire oneWire(ONE_WIRE_BUS);	

// Pass oneWire reference to DallasTemperature library
DallasTemperature sensors(&oneWire);

void setup()
{
  sensors.begin();	// Start up the library
  //initialize lcd screen
  lcd.init();
  // turn on the backlight
  lcd.backlight();
  lcd.setCursor(0,0);

  pinMode(buttonPin, INPUT);
  attachInterrupt(digitalPinToInterrupt(buttonPin), flagSetter, RISING);
}

void loop()
{
  // Send the command to get temperatures
  sensors.requestTemperatures(); 

  lcd.clear();
  lcd.print("Temperature:");
  
  if (tempCelsius) {
    lcd.print(sensors.getTempCByIndex(0));
    lcd.print(char(223));
    lcd.print("C");
  } else {
    lcd.print((sensors.getTempCByIndex(0) * 9.0) / 5.0 + 32.0);
    lcd.print(char(223));
    lcd.print("F");
  }
  delay(1000); 
  
}

void flagSetter(){
  tempCelsius = !tempCelsius;
}