#include <Keypad.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// Initialize the I2C LCD (Set the correct I2C address and LCD dimensions)
LiquidCrystal_I2C lcd(0x27, 16, 2); // Change 0x27 to your LCD I2C address

// Define the keypad layout
const byte ROWS = 4;  // Four rows
const byte COLS = 4;  // Four columns
char keys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

byte rowPins[ROWS] = {12, 13, 14, 15};  // Connect to the row pins of the keypad
byte colPins[COLS] = {16, 17, 18, 19}; // Connect to the column pins of the keypad

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

// Define the correct password
const String correctPassword = "1234"; // Replace with your password
String enteredPassword = ""; // Buffer to store entered password

void setup() {
  // Initialize LCD
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("Enter Password:");

  // Start Serial Monitor (optional for debugging)
  Serial.begin(115200);
}

void loop() {
  char key = keypad.getKey(); // Get a key press from the keypad

  if (key) { // If a key is pressed
    Serial.print(key); // Print the key to Serial Monitor for debugging

    if (key == '#') { // '#' is the submit key
      lcd.clear();
      if (enteredPassword == correctPassword) {
        lcd.print("Password Correct!");
        Serial.println("\nPassword Correct!");
      } else {
        lcd.print("Password Incorrect!");
        Serial.println("\nPassword Incorrect!");
      }
      delay(2000); // Show the result for 2 seconds
      lcd.clear();
      lcd.print("Enter Password:");
      enteredPassword = ""; // Clear the entered password
    } else if (key == '*') { // '*' is the clear key
      enteredPassword = ""; // Clear the entered password buffer
      lcd.clear();
      lcd.print("Password Cleared!");
      delay(1000); // Wait 1 second before showing the main screen
      lcd.clear();
      lcd.print("Enter Password:");
    } else {
      // Add the pressed key to the password buffer
      enteredPassword += key;

      // Display entered password as '*'
      lcd.setCursor(0, 1);
      for (int i = 0; i < enteredPassword.length(); i++) {
        lcd.print('*');
      }
    }
  }
}