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

LiquidCrystal_I2C lcd(0x27, 16, 2);

const int buttonPin = 7;
const int ledPin = 9;
const int buzzerPin = 8;

unsigned long startTime = 0;
bool running = false;

void setup() {
  
  lcd.init();
  lcd.backlight();
  
    lcd.setCursor(3, 0);
  lcd.print("CRONOMETRU");

  
  pinMode(buttonPin, INPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);

  digitalWrite(ledPin, LOW);
  digitalWrite(buzzerPin, LOW);

  updateLCD(0);
}

void loop() {
  if (digitalRead(buttonPin) == HIGH && !running) {
    running = true;
    startTime = millis();
  }

  if (running) {
    unsigned long currentTime = millis();
    unsigned long elapsedTime = (currentTime - startTime) / 1000;

    if (elapsedTime <= 60) {
      updateLCD(elapsedTime);
      controlLED(elapsedTime);
      controlBuzzer(elapsedTime);
    } else {
      running = false;
      digitalWrite(ledPin, LOW);
      digitalWrite(buzzerPin, LOW);
    }
  }
}

void updateLCD(unsigned long seconds) {
  int minutes = seconds / 60;
  int secs = seconds % 60;

  char buffer[6];
  sprintf(buffer, "%02d:%02d", minutes, secs);

  lcd.setCursor(5, 1);
  lcd.print(buffer);
}

void controlLED(unsigned long seconds) {
  if (seconds >= 15 && seconds <= 25) {
    digitalWrite(ledPin, HIGH);
  } else if (seconds >= 26 && seconds <= 40) {
    if ((seconds % 2) == 0) {
      digitalWrite(ledPin, LOW);
    } else {
      digitalWrite(ledPin, HIGH);
    }
  } else if (seconds >= 41) {
    digitalWrite(ledPin, LOW);
  }
}

void controlBuzzer(unsigned long seconds) {
  if (seconds >= 50 && seconds <= 60) {
    if ((seconds % 2) == 0) {
      digitalWrite(buzzerPin, HIGH);
    } else {
      digitalWrite(buzzerPin, LOW);
    }
  } else {
    digitalWrite(buzzerPin, LOW);
  }
}