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

// Define constants
const int addr = 0x27; // Address of your I2C LCD
const int btnPlus = 2;
const int btnMinus = 3;
const int btnSet = 4;
const int btnMode = 5;
const int buzzer = 6; // Define the pin connected to the buzzer

// Define note frequencies (in Hz)
const int NOTE_C4 = 261;
const int NOTE_D4 = 294;
const int NOTE_E4 = 329;
const int NOTE_F4 = 349;
const int NOTE_G4 = 392;
const int NOTE_A4 = 440;
const int NOTE_B4 = 494;
const int NOTE_C5 = 523;

// Melodi sederhana untuk alarm
int melody[] = { NOTE_C4, NOTE_D4, NOTE_E4, NOTE_F4, NOTE_G4, NOTE_A4, NOTE_B4, NOTE_C5 };
int noteDurations[] = { 4, 4, 4, 4, 4, 4, 4, 4 }; // Setiap nada berdurasi 1/4 detik

// Global variables
RTC_DS3231 rtc;
LiquidCrystal_I2C lcd(addr, 16, 2);
boolean isSettingAlarm = false;
boolean isAlarmActive = false;
int alarmHour = 0;
int alarmMinute = 0;
int settingMode = 0; // 0: hour, 1: minute
unsigned long lastDebounceTime = 0;
unsigned long debounceDelay = 200;
unsigned long alarmStartTime = 0; // To track the start time of the alarm

// Variables to track previous state
int lastHour = -1;
int lastMinute = -1;
int lastSecond = -1;
int lastAlarmHour = -1;
int lastAlarmMinute = -1;
boolean lastIsSettingAlarm = false;
int lastSettingMode = -1;

void setup() {
  // Initialize serial, RTC, LCD, and buttons
  Serial.begin(9600);
  if (!rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }
  lcd.init();
  lcd.backlight();
  pinMode(btnPlus, INPUT_PULLUP);
  pinMode(btnMinus, INPUT_PULLUP);
  pinMode(btnSet, INPUT_PULLUP);
  pinMode(btnMode, INPUT_PULLUP);
  pinMode(buzzer, OUTPUT); // Set buzzer pin as output
}

void loop() {
  DateTime now = rtc.now();

  // Check if alarm is triggered
  if (now.hour() == alarmHour && now.minute() == alarmMinute && !isAlarmActive) {
    isAlarmActive = true;
    alarmStartTime = millis(); // Record the start time of the alarm
    Serial.println("Alarm!");
    playMelody(); // Play the melody when alarm triggers
  }

  // If alarm is active, check if 30 seconds have passed
  if (isAlarmActive && (millis() - alarmStartTime >= 30000)) {
    isAlarmActive = false;
    noTone(buzzer); // Stop the buzzer after 30 seconds
  }

  // Handle button presses with debounce and sound buzzer
  if ((millis() - lastDebounceTime) > debounceDelay) {
    if (digitalRead(btnMode) == LOW) {
      isSettingAlarm = !isSettingAlarm;
      lastDebounceTime = millis();
      tone(buzzer, 500, 100); // Sound buzzer briefly on button press
    }

    if (isSettingAlarm) {
      if (digitalRead(btnPlus) == LOW) {
        if (settingMode == 0) {
          alarmHour = (alarmHour + 1) % 24;
        } else {
          alarmMinute = (alarmMinute + 1) % 60;
        }
        lastDebounceTime = millis();
        tone(buzzer, 500, 100); // Sound buzzer briefly on button press
      } else if (digitalRead(btnMinus) == LOW) {
        if (settingMode == 0) {
          alarmHour = (alarmHour + 23) % 24;
        } else {
          alarmMinute = (alarmMinute + 59) % 60;
        }
        lastDebounceTime = millis();
        tone(buzzer, 500, 100); // Sound buzzer briefly on button press
      }

      if (digitalRead(btnSet) == LOW) {
        settingMode = (settingMode + 1) % 2;
        lastDebounceTime = millis();
        tone(buzzer, 500, 100); // Sound buzzer briefly on button press
      }
    }
  }

  // Update time display only if it changes
  if (now.hour() != lastHour || now.minute() != lastMinute || now.second() != lastSecond) {
    lcd.setCursor(0, 0);
    lcd.print(now.hour() < 10 ? "0" : "");
    lcd.print(now.hour(), DEC);
    lcd.print(":");
    lcd.print(now.minute() < 10 ? "0" : "");
    lcd.print(now.minute(), DEC);
    lcd.print(":");
    lcd.print(now.second() < 10 ? "0" : "");
    lcd.print(now.second(), DEC);

    lastHour = now.hour();
    lastMinute = now.minute();
    lastSecond = now.second();
  }

  // Update alarm display only if necessary
  if (isSettingAlarm != lastIsSettingAlarm || settingMode != lastSettingMode ||
      alarmHour != lastAlarmHour || alarmMinute != lastAlarmMinute) {
    lcd.setCursor(0, 1);
    lcd.print("                ");  // Clear the second line
    lcd.setCursor(0, 1);
    if (isSettingAlarm) {
      if (settingMode == 0) {
        lcd.print("Set Hour: ");
        lcd.print(alarmHour < 10 ? "0" : "");
        lcd.print(alarmHour, DEC);
      } else {
        lcd.print("Set Minute: ");
        lcd.print(alarmMinute < 10 ? "0" : "");
        lcd.print(alarmMinute, DEC);
      }
    } else {
      lcd.print("Alarm: ");
      lcd.print(alarmHour < 10 ? "0" : "");
      lcd.print(alarmHour, DEC);
      lcd.print(":");
      lcd.print(alarmMinute < 10 ? "0" : "");
      lcd.print(alarmMinute, DEC);
    }

    lastIsSettingAlarm = isSettingAlarm;
    lastSettingMode = settingMode;
    lastAlarmHour = alarmHour;
    lastAlarmMinute = alarmMinute;
  }
}

// Function to play melody
void playMelody() {
  for (int i = 0; i < 8; i++) {
    int noteDuration = 1000 / noteDurations[i];
    tone(buzzer, melody[i], noteDuration);
    delay(noteDuration * 1.30); // Pause between notes
    noTone(buzzer); // Stop the tone before playing the next one
  }
}