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

// Initialize the LCD library with the address of the I2C module
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Define the keypad
const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};
byte rowPins[ROWS] = {9,8,7,6}; // connect to the row pinouts of the keypad
byte colPins[COLS] = {5, 4, 3, 2}; // connect to the column pinouts of the keypad
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// Relay control pin
const int relayPin = 10;

// Variables to store selected time (two digits)
int tensDigit = 0;
int onesDigit = 0;

// Flag to indicate if washing is in progress
bool washingInProgress = false;
unsigned long washingStartTime = 0;
unsigned long washingDuration = 0;

void setup() {
  // Initialize LCD
  lcd.init();
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Select time (min)");

  // Initialize relay pin
  pinMode(relayPin, OUTPUT);
  digitalWrite(relayPin, LOW); // Make sure relay is initially off
}

void loop() {
  char key = keypad.getKey();

  if (key != NO_KEY) {
    if (key == 'A') {
      if (tensDigit > 0 || onesDigit > 0) {
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("OK");
        delay(1000); // Delay to show "OK" message
        lcd.clear(); // Clear LCD after showing "OK"
        lcd.setCursor(0, 0);
        lcd.print("Washing...");
        int selectedTime = tensDigit * 10 + onesDigit;
        startWashing(selectedTime * 60); // Start washing for selected time
        tensDigit = 0;
        onesDigit = 0;
      }
    } else if (key == 'B') {
      if (washingInProgress) {
        stopWashing();
      }
    } else if (key == 'C') {
      tensDigit = 0; // Clear selected time if 'C' is pressed
      onesDigit = 0;
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Select time (min)");
    } else if (isdigit(key)) {
      int digit = key - '0'; // Convert char to int for selected time

      if (tensDigit == 0) {
        tensDigit = digit;
        lcd.setCursor(0, 1);
        lcd.print("Selected: ");
        lcd.print(tensDigit);
        lcd.print(onesDigit);
        lcd.print(" min ");
      } else if (onesDigit == 0 && digit >= 0) {
        onesDigit = digit;
        lcd.setCursor(0, 1);
        lcd.print("Selected: ");
        lcd.print(tensDigit);
        lcd.print(onesDigit);
        lcd.print(" min ");
      }
    }
  }

  if (washingInProgress) {
    if (millis() - washingStartTime >= washingDuration) {
      stopWashing();
    }
  }
}

void startWashing(int seconds) {
  digitalWrite(relayPin, HIGH); // Activate relay
  washingInProgress = true;
  washingStartTime = millis();
  washingDuration = seconds * 1000; // Convert seconds to milliseconds
}

void stopWashing() {
  digitalWrite(relayPin, LOW); // Deactivate relay
  washingInProgress = false;
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Stopped");
  delay(2000); // Display "Stopped" message for 2 seconds
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Select time (min)");
}