#include <Keypad.h>
#include <LiquidCrystal.h>

// === Setup LCD (16x2) ===
// RS -> 12, E -> 11, D4 -> 10, D5 -> A0, D6 -> A1, D7 -> A2
LiquidCrystal lcd(12, 11, 10, A0, A1, A2);

// === Setup Keypad 4x4 ===
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] = {9, 8, 7, 6}; // R1..R4
byte colPins[COLS] = {5, 4, 3, 2}; // C1..C4

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

// === Password ===
String password = "1234";
String input = "";

// === LED ===
int ledPin = 13;

void setup() {
  pinMode(ledPin, OUTPUT);

  // Setup LCD
  lcd.begin(16, 2);
  lcd.print("Enter Password:");
  lcd.setCursor(0, 1);

  // Setup Serial Console
  Serial.begin(9600);
  Serial.println("System Ready - Enter Password:");
}

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

  if (key) {
    if (key == '#') {
      // cek password
      if (input == password) {
        lcd.clear();
        lcd.print("Access Granted");
        Serial.println("Access Granted ✅");

        digitalWrite(ledPin, HIGH); // LED ON
        delay(3000);
        digitalWrite(ledPin, LOW);  // LED OFF

        lcd.clear();
        lcd.print("Enter Password:");
      } else {
        lcd.clear();
        lcd.print("Access Denied");
        Serial.println("Access Denied ❌");

        digitalWrite(ledPin, LOW);
        delay(2000);

        lcd.clear();
        lcd.print("Enter Password:");
      }

      input = ""; // reset
      lcd.setCursor(0, 1);
    } 
    else if (key == '*') {
      // reset input
      input = "";
      lcd.clear();
      lcd.print("Enter Password:");
      lcd.setCursor(0, 1);
      Serial.println("Input Cleared");
    } 
    else {
      // input password
      input += key;
      lcd.print("*"); // tampil bintang
      Serial.print("Key pressed: ");
      Serial.println(key);
    }
  }
}