#include <Keypad.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);

const byte BARIS = 4; // JML BARIS KEYPAD
const byte KOLOM = 4; // JML KOLOM KEYPAD
char keys[BARIS][KOLOM] =  //membuat array keypad
{
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};
byte colPins[KOLOM] = {5, 4, 2, 15};
byte rowPins[BARIS] = {14, 12, 19, 18};
Keypad customKeypad = Keypad(makeKeymap(keys), rowPins, colPins, BARIS, KOLOM);

char customKey; //var penampung keypad
int number=0; //var penampung nilai angka
int password=123; //password
int ledhijau=25;
int ledmerah=26;

void setup() {
  // put your setup code here, to run once:
  pinMode(ledhijau, OUTPUT);
  pinMode(ledmerah, OUTPUT);
  lcd.init();
  lcd.backlight();
}

void loop() {
  // put your main code here, to run repeatedly:
  lcd.setCursor(0,0);
  lcd.print("Input Password");      //Tampilan pada layar LCD
  
  customKey = customKeypad.getKey();    //Baca input keypad

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

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

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