// ESP32 Digital Clock + Alarm + Progressive Buzzer
// Wokwi Ready Version

const int buzzerPin = 25;
const int hourBtn = 32;
const int minuteBtn = 33;
const int alarmBtn = 26;

const int pwmFreq = 2000;
const int pwmResolution = 8;

int currentHour = 12;
int currentMinute = 0;
int currentSecond = 45;

int alarmHour = 12;
int alarmMinute = 1;

bool alarmEnabled = true;
bool alarmRunning = false;

bool lastHourState = HIGH;
bool lastMinuteState = HIGH;
bool lastAlarmState = HIGH;

int duty = 0;

unsigned long previousMillis = 0;
unsigned long buzzerMillis = 0;


void setup() {
  Serial.begin(115200);

  pinMode(hourBtn, INPUT_PULLUP);
  pinMode(minuteBtn, INPUT_PULLUP);
  pinMode(alarmBtn, INPUT_PULLUP);

  ledcAttach(buzzerPin, pwmFreq, pwmResolution);
  ledcWrite(buzzerPin, 0);

  Serial.println("Clock Started");
}

void loop() {

  unsigned long currentMillis = millis();

  // CLOCK UPDATE EVERY 1 SECOND
  if (currentMillis - previousMillis >= 1000) {
    previousMillis = currentMillis;

    currentSecond++;

    if (currentSecond >= 60) {
      currentSecond = 0;
      currentMinute++;
    }

    if (currentMinute >= 60) {
      currentMinute = 0;
      currentHour++;
    }

    if (currentHour >= 24) {
      currentHour = 0;
    }

    printTime();
  }

  // READ BUTTONS
  handleButtons();

  // CHECK ALARM CONDITION
  if (alarmEnabled &&
      currentHour == alarmHour &&
      currentMinute == alarmMinute &&
      currentSecond == 0 &&
      !alarmRunning) {

    alarmRunning = true;
    duty = 0;
    Serial.println("ALARM STARTED");
  }

  // PROGRESSIVE BUZZER
  if (alarmRunning) {
    if (currentMillis - buzzerMillis >= 2000) {
      buzzerMillis = currentMillis;

    //   duty += 10;
    //   if (duty > 200) duty = 200;

    //   ledcWrite(buzzerPin, duty);

    //   Serial.print("Buzzer Duty: ");
    //   Serial.println(duty);
    // }
    static int freq = 1000;
    freq += 500;
    if (freq > 5000) freq = 1000;

    ledcAttach(buzzerPin, freq, pwmResolution);
    ledcWrite(buzzerPin, 128);     // constant duty

    Serial.print("Frequency: ");
    Serial.println(freq);
  }
}
}

// ---------------------- FUNCTIONS ----------------------

void handleButtons() {

  bool currentHourState = digitalRead(hourBtn);
  bool currentMinuteState = digitalRead(minuteBtn);
  bool currentAlarmState = digitalRead(alarmBtn);

  // Hour button
  if (lastHourState == HIGH && currentHourState == LOW) {
    alarmHour++;
    if (alarmHour >= 24) alarmHour = 0;
    Serial.print("Alarm Hour: ");
    Serial.println(alarmHour);
    while(digitalRead(hourBtn) == LOW);
    delay(200);
  }

  // Minute button
  if (lastMinuteState == HIGH && currentMinuteState == LOW) {
    alarmMinute++;
    if (alarmMinute >= 60) alarmMinute = 0;
    Serial.print("Alarm Minute: ");
    Serial.println(alarmMinute);
    while(digitalRead(minuteBtn) == LOW);
    delay(200);
  }

  // Alarm enable button
  if (lastAlarmState == HIGH && currentAlarmState == LOW) {

    if (alarmRunning) {
      alarmRunning = false;
      ledcWrite(buzzerPin, 0);
      duty = 0;
      Serial.println("Alarm Stopped");
    } else {
      alarmEnabled = !alarmEnabled;
      Serial.println(alarmEnabled ? "Alarm Enabled" : "Alarm Disabled");
    }
    while(digitalRead(alarmBtn) == LOW);
    delay(200);
  }

  lastHourState = currentHourState;
  lastMinuteState = currentMinuteState;
  lastAlarmState = currentAlarmState;
}

void printTime() {
  Serial.print("Time: ");
  Serial.print(currentHour);
  Serial.print(":");
  Serial.print(currentMinute);
  Serial.print(":");
  Serial.println(currentSecond);
}