#include <Wire.h>
#include <RTClib.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

#define OLED_RESET    -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

RTC_DS3231 rtc;

const int buzzerPin = 9; // Connect buzzer to pin 9
const int buttonHourPin = 7; // Button for setting hour
const int buttonMinutePin = 8; // Button for setting minute

DateTime alarmTime;

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

  pinMode(buzzerPin, OUTPUT);
  pinMode(buttonHourPin, INPUT_PULLUP);
  pinMode(buttonMinutePin, INPUT_PULLUP);

  if (!rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }

  if (rtc.lostPower()) {
    Serial.println("RTC lost power, let's set the time!");
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }

  // Set default alarm time (8:00 AM)
  alarmTime = DateTime(rtc.now().year(), rtc.now().month(), rtc.now().day(), 8, 0, 0);

  // Initialize the display
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  display.display(); // Clear the buffer
  delay(2000); // Pause for 2 seconds
}

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

  // Check if buttons are pressed to set the alarm time
  if (digitalRead(buttonHourPin) == LOW) {
    delay(10); // Debounce delay reduced to 10 milliseconds
    if (digitalRead(buttonHourPin) == LOW) {
      alarmTime = alarmTime + TimeSpan(0, 1, 0, 0); // Increment hour
    }
  }

  if (digitalRead(buttonMinutePin) == LOW) {
    delay(10); // Debounce delay reduced to 10 milliseconds
    if (digitalRead(buttonMinutePin) == LOW) {
      alarmTime = alarmTime + TimeSpan(0, 0, 1, 0); // Increment minute
    }
  }

  // Check if it's time for the alarm
  if (now.hour() == alarmTime.hour() && now.minute() == alarmTime.minute()) {
    tone(buzzerPin, 1000); // Generate a tone of 1000 Hz on the buzzer pin
  } else {
    noTone(buzzerPin); // Stop generating the tone
  }

  // Display current time and alarm time on OLED display
  display.clearDisplay();
  display.setTextSize(1);      
  display.setTextColor(SSD1306_WHITE); 
  display.setCursor(0,0);     
  display.print("Current Time:");
  display.setCursor(0,10);    
  display.print(now.year(), DEC);
  display.print('/');
  display.print(now.month(), DEC);
  display.print('/');
  display.print(now.day(), DEC);
  display.print(" ");
  display.print(now.hour(), DEC);
  display.print(':');
  display.print(now.minute(), DEC);
  
  display.setCursor(0,30);    
  display.print("Alarm Time:");
  display.setCursor(0,40);    
  display.print(alarmTime.year(), DEC);
  display.print('/');
  display.print(alarmTime.month(), DEC);
  display.print('/');
  display.print(alarmTime.day(), DEC);
  display.print(" ");
  display.print(alarmTime.hour(), DEC);
  display.print(':');
  display.print(alarmTime.minute(), DEC);
  
  display.display(); 

  delay(10); // Update every second
}