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

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] = {13, 12, 14, 27};
byte colPins[COLS] = {26, 25, 33, 32};

Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );

char customKey;      //Variabel penampung input keypad
int number = 0;      //Variabel penampung nilai angka
int password = 1234; //Password

LiquidCrystal_I2C lcd(0x27, 16, 2);

int i = 0;

void setup(){
  lcd.init();
  lcd.backlight();
}

void loop() 
{
  lcd.setCursor(0,0);
  lcd.print("Input Password"); //Tampilan pada layar LCD
  
  customKey = keypad.getKey(); //Baca input keypad

  //------------Prosedur jika input berupa angka------------//
  switch(customKey){
    case '0' ... '9':
      lcd.setCursor(i,1);
      number = number * 10 + (customKey - '0');
      lcd.print("*");
      i++;
    break;

    //------------Jika input '#' maka cek password------------//
    case '#':
      if(number == password){          //Jika password benar, maka
        lcd.setCursor(0,1);
        lcd.print("Access Accepted "); //Tampilan LCD
        delay(2000);
        number = 0;
        i = 0;
        lcd.clear(); 
      }
      else{                            //Jika salah, maka
        lcd.setCursor(0,1);
        lcd.print("Invalid Password"); //Tampilan LCD
        delay(2000);
        number = 0;
        i = 0;
        lcd.clear();
      }
    break;

    //------------Jika input '*' maka hapus tampilan------------//
    case '*':
      number = 0;
      i = 0;
      lcd.clear();
    break;
  }
}