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

#define LEBAR   128
#define PANJANG 64

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

Keypad customKeypad = Keypad(makeKeymap(Keys),rowPins,colPins,ROWS,COLS);

char customKey;
int number = 0;
int password = 123123;
int position = 0;
int delPos = 0;

Adafruit_SSD1306 oled(LEBAR, PANJANG, &Wire, -1);

void setup(){
    Serial.begin(9600);

    if(!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)){
      Serial.println(F("failed to start SSD1306 OLED"));
      while(1);
    }

    delay(2000);
    oled.clearDisplay();

    oled.setTextSize(1);
    oled.setTextColor(WHITE);
    oled.setCursor(20,10);
    oled.println("WELCOME!!!");
    oled.display();
    delay(1500);
    oled.clearDisplay();
}

void loop(){
    oled.setCursor(0,0);
    oled.print("Please Input Pass");
    oled.display();
    
    customKey = customKeypad.getKey();

      switch(customKey){
        case '0' ... '9' :
          oled.setCursor(0,10);
          number = number * 10 + (customKey - '0');
          oled.print(number);
          oled.display();
          position += 1;
        break;

        case '#' :
          if(number == password){
            oled.setCursor(0,10);
            oled.print("Access Acceoted");
            number = 0;
            oled.display();
            oled.clearDisplay();
          }
          else{
            oled.setCursor(0,10);
            oled.print("Invalid Password");
            oled.display();
            number = 0;
            delay(1500);
            oled.clearDisplay();
          }
        break;

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

        break;

        case 'D' :
          oled.clearDisplay();
          if(number == 0){
            oled.setCursor(0,10);
            oled.print("");
          }else{
            oled.setCursor(0,10);
            oled.print(number);
          }
          oled.setCursor(0,10);
          oled.print(number);
          
          oled.display();
          position -= 1;
          
        break;
      }
}