#include <Keypad.h>

const char* correctPassword = "1234";
char enteredPassword[5];
int position = 0;

const int relayPin = 13;   // Pin for Relay
const int buzzerPin = 12;  // Pin for Buzzer

// Define the Keypad
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] = {5, 18, 19, 21}; // Connect to the row pinouts of the keypad
byte colPins[COLS] = {22, 23, 25, 26}; // Connect to the column pinouts of the keypad

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

void setup() {
  Serial.begin(9600);
  pinMode(relayPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  digitalWrite(relayPin, LOW); // Ensure relay is off initially
  digitalWrite(buzzerPin, LOW);
}

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

  if (key) {
    Serial.print("Key Pressed: ");
    Serial.println(key);  // Print the key to Serial Monitor
    
    if (key == '#') {
      enteredPassword[position] = '\0';  // Null-terminate the string
      checkPassword();
      position = 0;  // Reset position for next input
    } 
    else if (key == '*') {
      // Reset the entered password
      position = 0;
      Serial.println("Password cleared!");
    }
    else {
      enteredPassword[position] = key;
      position++;
    }
  }
}

void checkPassword() {
  if (strcmp(enteredPassword, correctPassword) == 0) {
    Serial.println("Correct Password!");
    digitalWrite(relayPin, HIGH); // Turn on the relay to power the LED
    delay(10000); // Keep LED on for 10 seconds
    digitalWrite(relayPin, LOW);  // Turn off the relay after 10 seconds
  } else {
    Serial.println("Incorrect Password!");
    tone(buzzerPin, 1000, 2000); // Buzzer on for 2 seconds
  }
}