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

#define I2C_ADDR 0x27
#define LCD_COLUMNS 16
#define LCD_LINES 2

const uint8_t ROWS = 4;
const uint8_t COLS = 4;
char keys[ROWS][COLS] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};

uint8_t colPins[COLS] = { 5, 4, 3, 2 }; // Pins connected to C1, C2, C3, C4
uint8_t rowPins[ROWS] = { 9, 8, 7, 6 }; // Pins connected to R1, R2, R3, R4

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);
LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);

String input = "";
void setup() {
  Serial.begin(9600);
  lcd.init();
  lcd.backlight();
  lcd.print("Yoyo");

}

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

  if (key != NO_KEY) {
    Serial.println(key);
  }
  if (key) { // Jeśli naciśnięto klawisz
    if (key == '#') {  // Kasowanie wpisu
      input = "";
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Wpisz liczbe:");
      lcd.setCursor(0, 1);
    }
    else if (key == '*') {  // Potwierdzenie wpisu
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Wpisano:");
      lcd.setCursor(0, 1);
      lcd.print(input);
      delay(2000);
      input = "";
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Wpisz liczbe:");
      lcd.setCursor(0, 1);
    }
    else {  // Wpisywanie liczby
      if (input.length() < 16) { // Maksymalnie 16 znaków
        input += key;
        lcd.setCursor(0, 1);
        lcd.print(input);
      }
    }
  }
}