#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Keypad.h>

#define LEBAR_LAYAR 128
#define TINGGI_LAYAR 64

const byte BARIS = 4;
const byte KOLOM = 4;

Adafruit_SSD1306 oled(LEBAR_LAYAR, TINGGI_LAYAR, &Wire, -1);

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

byte rowPins[BARIS] = {14, 12, 19, 18};
byte colPins[KOLOM] = {5, 4, 2, 15};

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, BARIS, KOLOM);

char customkey;
int number=0;
int password = 9510;

void setup(){
  Serial.begin(9600);
  if(!oled.begin(SSD1306_SWITCHCAPVCC, 0x3c)){
    Serial.println(F("Failed to Start SSD1306 OLED"));
    while(1);
  }
  oled.clearDisplay();
  oled.setTextSize(1);
  oled.setTextColor(WHITE);
  oled.setCursor(20,20);
  oled.println("SELAMAT DATANG");
  delay(2000);
  oled.display();
  oled.clearDisplay();
}

void loop(){
  oled.setTextSize(1);
  oled.setTextColor(WHITE);
  oled.setCursor(0,0);
  oled.println("INPUT PASSWORD!");

  customkey = keypad.getKey();
  switch(customkey){
    case '0'...'9':
      oled.setTextSize(1);
      oled.setTextColor(WHITE);
      oled.setCursor(0,10);
      number = number*10 + (customkey - '0');
      oled.print(number);
      oled.display();
      oled.clearDisplay();
    break;

    case '#':
      if(number == password){
        oled.setTextSize(1);
        oled.setTextColor(WHITE);
        oled.setCursor(0,10);
        oled.print("Access Granted");
        delay(2000);
        number=0;
        oled.display();
        oled.clearDisplay();
      }
      else{
        oled.setTextSize(1);
        oled.setTextColor(WHITE);
        oled.setCursor(0,10);
        oled.print("Invalid Password");
        delay(2000);
        number=0;
        oled.clearDisplay();
      }
    break;

    case '*':
      number=0;
      oled.clearDisplay();
    break;
  }
}