#include<RTClib.h>
#include<LiquidCrystal.h>

RTC_DS1307 rtc;
LiquidCrystal lcd(12,11,7,6,5,4);

const int Button1 = 8;
const int Button2 = 9;
const int Button3 = 10;
const int Button4 = 3;
const int SPK = 13;
int mode = 0;
unsigned long Time, TimeCurrent = 0;
int SetHour = 0, SetMinute = 0, SetSecond = 0;

void setup()
{
  if(! rtc.begin())
  {
    Serial.flush();
    while(1) delay(10);
  }

  if(! rtc.isrunning())
  {
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }

  lcd.begin(16,2);

  pinMode(Button1,INPUT_PULLUP);
  pinMode(Button2,INPUT_PULLUP);
  pinMode(Button3,INPUT_PULLUP);
  pinMode(Button4,INPUT_PULLUP);
  pinMode(SPK,OUTPUT);

  Serial.begin(9600);

}

void InputMode()
{
  if(digitalRead(Button1) == LOW)
  {
    delay(20);
    if(digitalRead(Button1) == LOW)
    {
      mode++;
      lcd.clear();
      if(mode > 3)
      {
        mode = 0;
      }
    } 
    while(digitalRead(Button1) == LOW);
  }
}

void PrintTime(int Time, int d1, int d2, int line)
{
  if(Time < 10)
  {
    lcd.setCursor(d1,line);
    lcd.print("0");
    lcd.setCursor(d2,line);
    lcd.print(Time); 
  }
  else 
  {
    lcd.setCursor(d1,line);
    lcd.print(Time);
  }
}

void loop()
{
  InputMode();
  Serial.println(mode);

  DateTime Now = rtc.now();

  if(mode == 0)
  {
    lcd.setCursor(5,0);
    lcd.print("R-HUST");
    InputMode();
  }

  if(mode == 1)
  {
    lcd.setCursor(2,0);
    lcd.print("CAO XUAN DUC");
    lcd.setCursor(1,1);
    lcd.print("MSSV  20216089");
    InputMode();
  }

  if(mode == 2)
  {
    lcd.setCursor(0,0);
    lcd.print("TIME:");
    PrintTime(Now.hour(),6,7,0);
    lcd.setCursor(8,0);
    lcd.print(":");
    PrintTime(Now.minute(),9,10,0);
    lcd.setCursor(11,0);
    lcd.print(":");
    PrintTime(Now.second(),12,13,0);

    lcd.setCursor(0,1);
    lcd.print("DATE:");
    PrintTime(Now.day(),6,7,1);
    lcd.setCursor(8,1);
    lcd.print("/");
    PrintTime(Now.month(),9,10,1);
    lcd.setCursor(11,1);
    lcd.print("/");
    PrintTime(Now.year(),12,13,1);

    InputMode();
  }

  if(mode == 3)
  {
    lcd.setCursor(1,0);
    lcd.print("Set Alarm Clock:");

    PrintTime(SetHour,4,5,1);
    lcd.setCursor(6,1);
    lcd.print(":");
    PrintTime(SetMinute,7,8,1);
    lcd.setCursor(9,1);
    lcd.print(":");
    PrintTime(SetSecond,10,11,1);

    if(digitalRead(Button2) == LOW)
    {
      delay(20);
      if(digitalRead(Button2) == LOW)
      {
        SetHour++;
        delay(20);
        if(SetHour == 24) SetHour = 0;
      }   
      while(digitalRead(Button2) == LOW);
    }

    if(digitalRead(Button3) == LOW)
    {
      delay(20);
      if(digitalRead(Button3) == LOW)
      {
        SetMinute++;
        delay(20);
        if(SetMinute == 60) SetMinute = 0;
      }
      while(digitalRead(Button3) == LOW);
    } 

    if(digitalRead(Button4) == LOW)
    {
      delay(20);
      if(digitalRead(Button4) == LOW)
      {
        SetSecond++;
        if(SetSecond == 60) SetSecond = 0;
      }
      while(digitalRead(Button4) == LOW);
    }
    InputMode();
  }

  if(SetHour == Now.hour() && SetMinute == Now.minute())
  {
    if(SetSecond == Now.second())
    {
      digitalWrite(SPK,HIGH);
      tone(SPK,4000,3000);
    }
  }
}