#include <RTClib.h>
#include <ezButton.h>;

RTC_DS1307 rtc;

byte clk=2;
byte dt=3;
byte sw=4;

ezButton button(sw);

String rtc_date = "";
String rtc_time = "";

int counter=0;
int prev_counter=0;
int flag=0;

void setup(){
  Serial.begin(9600);
  if (!rtc.begin()){
    //Serial.println("RTC not initialised");
    while(true);
  }
  //Serial.println("RTC found");
  attachInterrupt(digitalPinToInterrupt(clk),encoder,FALLING);
  button.setDebounceTime(25);
}

void encoder(){
  prev_counter=counter;
  if(digitalRead(dt)==HIGH) counter++;
  else counter--;
  counter=constrain(counter,0,3);
  flag=1;
}

void mode_selector(){
  if(prev_counter!=counter && flag==1){
    if(counter==0){
      Serial.println("DATE AND TIME");
    }
    else if(counter==1){
      Serial.println("SET ALARM");
    }
    else if(counter==2){
      Serial.println("STOPWATCH");
    }
    else if(counter==3){
      Serial.println("COUNTDOWN TIMER");
    }
    flag=0;
  }
}

void loop(){
  button.loop();
  if(button.isPressed()) select_mode();
  //  RTC date and time
  //DateTime dt = rtc.now();
  //rtc_date = get_date(dt);
  //Serial.println(rtc_date);
  //rtc_time = get_time(dt);
  //Serial.println(rtc_time);
  mode_selector();
  delay(10);
}

String get_time(DateTime current){

  int hour = current.hour();
  int minute = current.minute();
  int second = current.second();

  String current_time = "Time : " + String(hour) + ":" + String(minute) + 
                        ":" + String(second);

  return current_time;
}

String get_date(DateTime current){

  int year = current.year();
  int month = current.month();
  int day = current.day();

  String current_date = "Date : " + String(day) + "/" + String(month) + 
                "/" + String(year);
  
  return current_date;
}

void select_mode(){
  if(counter==0) Serial.println("DATE AND TIME IS SELECTED");
  if(counter==1) Serial.println("SET ALARM IS SELECTED");
  if(counter==2) Serial.println("STOPWATCH IS SELECTED");
  if(counter==3) Serial.println("COUNTDOWN TIMER IS SELECTED");
}