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

Servo myServo; // Create a servo object

const int servoPin = 11; // Pin connected to the servo signal wire

// Password Length 
const int Password_Length = 4;
// Character to hold password input
String Data;
// Password 
String Master = "1234";
// degree of the servo on correct password state
int correct_degree = 90;
// degree of the servo on correct password state
int incorrect_degree = 0;
// Counter for character entries
byte data_count = 0;

// Character to hold key input
char customKey;

// Constants for row and column sizes
const byte ROWS = 4;
const byte COLS = 4;

// Array to represent keys on keypad
char hexaKeys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

// Connections to Arduino
byte rowPins[ROWS] = {9, 8, 7, 6};
byte colPins[COLS] = {5, 4, 3, 2};

// Create keypad object
Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);

// Create LCD object
LiquidCrystal lcd(13, 12, A0, A1, A2, A3);

void setup() {
  // Setup LCD with begin
  lcd.begin(16, 2);
  myServo.attach(servoPin); // Attach the servo to the specified pin
  // Set lockOutput as an OUTPUT pin (relay)
  myServo.write(0); // Move the servo directly to 0 degrees
}

void loop() {

  // Initialize LCD and print
  lcd.setCursor(0, 0);
  lcd.print("Enter Password:");

  // Check for keypress
  customKey = customKeypad.getKey();

  // Handle keypress if valid
  if (customKey && data_count < Password_Length) {
    // Enter keypress into array and increment counter
    Data += customKey;
    lcd.setCursor(data_count, 1);
    lcd.print('*'); // Display asterisks for privacy
    data_count++;
  }

  // Check if password entered and "#" pressed
  if (customKey == '#' && data_count == Password_Length) {
    lcd.clear();

   if (Data == Master) {
      // Correct Password
      lcd.print("Correct: ");
      lcd.setCursor(0, 1);
      lcd.print(Master); // Display the correct password,
      // Turn on relay for 5 seconds
      myServo.write(correct_degree); // Move the servo to a specific degrees
      delay(5000);
      myServo.write(incorrect_degree); // Move the servo to a specific degrees

    } else {
      // Incorrect Password
      lcd.print("Incorrect");
      delay(1000);
    }

    // Clear data and LCD display
    lcd.clear();
    clearData();
  }
}

void clearData() {
  // Reset data_count
  data_count = 0;
  // Reset Data
  Data = "";
}