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


#define password_length 8

char Data[password_length];

char Master[password_length] = "123A456";

byte data_count = 0;
// pin configuration 

const int relay_pin = 13;

LiquidCrystal_I2C lcd(0x27, 16, 4); //16x4 LCD with I2C address 0x27

/* Keypad setup */
const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns
//define the cymbols on the buttons of the keypads
char hexaKeys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};

byte rowPins[ROWS] = {2, 3, 4, 5}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {6, 7, 8, 9}; //connect to the column pinouts of the keypad

//initialize an instance of class NewKeypad
Keypad customKeypad = Keypad( makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS); 

void showStartupMessage() {
  lcd.setCursor(4, 0);
  lcd.print("Welcome!");
  delay(1000);

  lcd.setCursor(0, 1);
  String message = " ECE Department";
  for (byte i = 0; i < message.length(); i++) {
    lcd.print(message[i]);
    delay(100);
  }
  delay(500);
  lcd.clear();
}

void doorlocked(){
  digitalWrite(relay_pin, HIGH);
  lcd.setCursor(0,1);
  lcd.write("door locked");
  delay(2000);
  lcd.clear();
}

void doorunlocked(){
  digitalWrite(relay_pin, LOW);
  lcd.setCursor(0,1);
  lcd.write("door Unlocked");
  delay(2000);
  lcd.clear();
}

void setup(){

  Serial.begin(115200);

  lcd.begin(16, 2);  //starting lcd 
  lcd.backlight(); // turn on the back light 🚦 of lcd display 

  pinMode(relay_pin, OUTPUT);
  
  showStartupMessage();
}
  
void loop(){
  // char customKey = customKeypad.getKey();
  
  // if (customKey){
  //   lcd.println(customKey);
  //   lcd.clear();
  // }
  lcd.setCursor(0,0);
  lcd.print("enter password");

  char customKey = customKeypad.getKey();
  if(customKey){
    Data[data_count] = customKey;
    lcd.setCursor(data_count, 1);
    lcd.print(Data[data_count]);
    data_count++;
  }

if (data_count == password_length - 1) {
    lcd.clear();
 
    if (!strcmp(Data, Master)) {
      // Password is correct
      lcd.print("Correct");
      // Turn on relay for 5 seconds
      digitalWrite(relay_pin, HIGH);
      delay(5000);
      digitalWrite(relay_pin, LOW);
    }
    else {
      // Password is incorrect
      lcd.print("Incorrect");
      delay(1000);
    }
 
    // Clear data and LCD display
    lcd.clear();
    clear_data();
  }
} 

void clear_data(){
  while(data_count !=0){
    Data[data_count--] = 0;
  }
  return;
}