#include <Keypad.h>

const byte ROWS = 4; // Number of rows on the keypad
const byte COLS = 4; // Number of columns on the keypad
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}; // Pins connected to keypad rows
byte colPins[COLS] = {5, 4, 3, 2}; // Pins connected to keypad columns

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

const char* correctPassword = "1234"; // Set your desired password here (change to a stronger password)
int numTries = 0; // Track the number of attempted entries
const int maxTries = 3; // Maximum allowed attempts before lockout

void setup() {
  Serial.begin(9600); // Optional serial communication for debugging
  pinMode(11,OUTPUT);
  pinMode(10, OUTPUT); // Pin connected to an LED (optional for visual feedback)
}

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

  if (key) {
    Serial.print(key); // Optional: Print entered key for debugging

    // Password entry logic with lockout and visual feedback (LED)
    if (numTries < maxTries) {
      static String enteredPassword = ""; // Clear entered password on each new attempt
      enteredPassword += key;

      if (enteredPassword.length() == strlen(correctPassword)) {
        if (enteredPassword == correctPassword) {
          Serial.println(" - Access granted");
          digitalWrite(10, HIGH); // Turn on LED (optional)
          analogWrite(11, HIGH);
          delay(3000); // Simulate successful access action (e.g., door unlock)
          digitalWrite(10, LOW); // Turn off LED (optional)
          analogWrite(11, LOW);
          numTries = 0; // Reset attempt counter
          enteredPassword = ""; // Clear entered password
        } else {
          Serial.println(" - Wrong password");
          numTries++;
        }
      }
    } else {
      Serial.println(" - Maximum attempts reached. System locked.");
      // Implement lockout mechanism here (e.g., delay, alarm)
    }
  }
}