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

RTC_DS1307 rtc;

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

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

int mode = 0;
int prevCount = 0;
int flag = 1;

ezButton button(sw);

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

  button.setDebounceTime(25);

  if (!rtc.begin()) {
    Serial.println("RTC not initialised");
    while (true);
  }

  attachInterrupt(digitalPinToInterrupt(clk), encoder, FALLING);
}

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

void changeMode() {
  if (flag == 1 && prevCount != mode) {
    if (mode == 0) {
      Serial.println("Current Time");
    }
    else if (mode == 1) {
      Serial.println("Alarm");
    }
    else if (mode == 2) {
      Serial.println("Stopwatch");
    }
    else if (mode == 3) {
      Serial.println("World Clock");
    }
    flag = 0;
  }
}

void modeSelect() {
  if (mode == 0) {
    Serial.println("Date and time mode selected");
  }
  if (mode == 1) {
    Serial.println("Alarm mode selected");
  }
  if (mode == 2) {
    Serial.println("Stopwatch mode selected");
  }
  if (mode == 3) {
    Serial.println("World clock mode selected");
  }
}

void loop() {
  button.loop();

  if (button.isPressed()) {
    modeSelect();
  }
  changeMode();

  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;
}