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

const int encoderPinA = 2;
const int encoderPinB = 3;
const int encoderButtonPin = 4;
const int relayPin = 5;

int encoderPos = 0;
int lastEncoderPos = 0;
bool encoderButtonState = false;
bool encoderButtonStateLast = false;

unsigned long countdownDuration = 10 * 60 * 1000;
unsigned long startTime;
unsigned long remainingTime;

const unsigned long relayOffDelay = 5000; // Delay before turning off the relay, in milliseconds
unsigned long relayOffTime; // Time when the relay should be turned off

LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  pinMode(encoderPinA, INPUT);
  pinMode(encoderPinB, INPUT);
  pinMode(encoderButtonPin, INPUT_PULLUP);
  pinMode(relayPin, OUTPUT);

  lcd.begin();
  lcd.backlight();

  startTime = millis();
  remainingTime = countdownDuration;
  relayOffTime = 0;

  printTime();
}

void loop() {
  int a = digitalRead(encoderPinA);
  int b = digitalRead(encoderPinB);
  if (a != lastEncoderPos) {
    encoderPos += (a == b) ? 1 : -1;
    lastEncoderPos = a;
  }
  encoderButtonState = !digitalRead(encoderButtonPin);
  if (encoderButtonState && !encoderButtonStateLast) {
  }
  encoderButtonStateLast = encoderButtonState;

  if (encoderPos != lastEncoderPos) {
    if (encoderPos > lastEncoderPos) {
      remainingTime += 1000;
    } else {
      if (remainingTime > 1000) {
        remainingTime -= 1000;
      }
    }
    printTime();
    lastEncoderPos = encoderPos;
  }
  
  if (remainingTime <= 0) {
    lcd.clear();
    lcd.print("Time's up!");
    digitalWrite(relayPin, HIGH);
    relayOffTime = millis() + relayOffDelay;
    while (true) {}
  }
  
  remainingTime = countdownDuration - (millis() - startTime);
  printTime();
  
  if (remainingTime <= relayOffDelay && !relayOffTime) {
    relayOffTime = millis() + relayOffDelay;
  }
  
  if (relayOffTime && millis() >= relayOffTime) {
    digitalWrite(relayPin, LOW);
    relayOffTime = 0;
  }
}

void printTime() {
  lcd.setCursor(0, 0);
  lcd.print("Time: ");
  lcd.print(remainingTime / 60000);
  lcd.print(":");
  lcd.print((remainingTime % 60000) / 1000);
}