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

#define row_num 4
#define col_num 4

char keys[row_num][col_num] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};

byte row_pins[row_num] = {19, 18, 5, 17};
byte col_pins[col_num] = {16, 4, 2, 15};

LiquidCrystal_I2C lcd(0x27, 20, 4);

String password = "1234";
String input = "";

Keypad mykeypad = Keypad(makeKeymap(keys), row_pins, col_pins, row_num, col_num);

void setup() {
  lcd.init();  // Initialize the LCD
  lcd.clear();  // Clear the screen
  lcd.backlight();  // Turn on the backlight

  lcd.setCursor(0, 0);
  lcd.print("Enter password:");
  Serial.begin(9600); // Start serial communication
}

void loop() {
  char key = mykeypad.getKey();
  
  if (key) {
    if (key == '#') {  // When "#" is pressed, check the password
      lcd.clear();
      if (input == password) {
        lcd.setCursor(0, 0);
        lcd.print("Welcome Home!");
        delay(500);  // Display for 4 seconds

        // Send a signal to the second ESP32 to control the servo
        Serial.println("SUCCESS"); // Send 'SUCCESS' to second ESP32

      } else {
        lcd.setCursor(0, 0);
        lcd.print("Access denied!");
        delay(500);  // Show Access Denied for 2 seconds

        // Send a signal to the second ESP32 for failure
        Serial.println("FAILURE"); // Send 'FAILURE' to second ESP32
      }
      input = "";  // Reset input for the next attempt
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Enter password:");
    }
    else if (key == '*') {  // When "*" is pressed, clear the password input
      input = "";
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Password cleared");
      delay(1000);
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Enter password:");
    } else {
      input.concat(key);  // Add the key to the input string
      lcd.setCursor(input.length() - 1, 1);
      lcd.print('*');  // Display * for each entered character
    }
  } 
}