#include <TM1637.h> // Library for the TM1637 4-digit display

// --- Pins Configuration ---
const int buzzer = 8;
const int CLK = 2;
const int DIO = 3;
const int CLK_2 = 50;
const int DIO_2 = 51;

const int pauseButton = 4;
const int set10Button = 5;
const int set0Button = 6;
const int increaseButton = 7;
const int decreaseButton = 9;

// --- Timer and Display ---
int seconds = 600;
int lastDisplayedSeconds = -1;
bool isPaused = false;

unsigned long previousMillis = 0;
const unsigned long interval = 1000; // 1 second

TM1637 tm(CLK, DIO);
TM1637 tm_2(CLK_2, DIO_2);

void setup() {
  // Initialize displays
  tm.init();
  tm.set(BRIGHT_TYPICAL);
  tm_2.init();
  tm_2.set(BRIGHT_TYPICAL);

  // Pin setup
  pinMode(buzzer, OUTPUT);
  pinMode(pauseButton, INPUT_PULLUP);
  pinMode(set10Button, INPUT_PULLUP);
  pinMode(set0Button, INPUT_PULLUP);
  pinMode(increaseButton, INPUT_PULLUP);
  pinMode(decreaseButton, INPUT_PULLUP);
}

void loop() {
  handleButtons();
  updateTimer();
  updateDisplay();
}

void handleButtons() {
  if (digitalRead(pauseButton) == LOW) {
    delay(200);
    isPaused = !isPaused;
  }

  if (digitalRead(set10Button) == LOW) {
    delay(200);
    seconds = 600;
  }

  if (digitalRead(set0Button) == LOW) {
    delay(200);
    seconds = 0;
  }

  if (digitalRead(increaseButton) == LOW) {
    delay(200);
    seconds += 5;
    if (seconds > 600) seconds = 600;
  }

  if (digitalRead(decreaseButton) == LOW) {
    delay(200);
    seconds -= 5;
    if (seconds < 0) seconds = 0;
  }
}

void updateTimer() {
  unsigned long currentMillis = millis();
  if (!isPaused && (currentMillis - previousMillis >= interval)) {
    previousMillis = currentMillis;
    if (seconds > 0) {
      seconds--;
    } else {
      // Stop timer and alert
      isPaused = true;
      tone(buzzer, 1000, 500);
      delay(500);
      noTone(buzzer);
    }

    if (seconds == 600) { // Reached 10 minutes
      tone(buzzer, 1000, 1000);
    }
  }
}

void updateDisplay() {
  if (seconds != lastDisplayedSeconds) {
    lastDisplayedSeconds = seconds;
    int minutes = seconds / 60;
    int secs = seconds % 60;

    tm.display(0, minutes / 10);
    tm.display(1, minutes % 10);
    tm.display(2, secs / 10);
    tm.display(3, secs % 10);

    tm_2.display(0, minutes / 10);
    tm_2.display(1, minutes % 10);
    tm_2.display(2, secs / 10);
    tm_2.display(3, secs % 10);
  }
}