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

//khai bao LCD
LiquidCrystal_I2C lcd(0x27, 16, 2);

//Khai báo bàn phím
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] = {2, 3, 4, 5};
byte colPins[cols] = {6, 7, 8, 9};

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, rows, cols);

//khai bao khoa
Servo servo;
int pos = 0;

//pass
String pw = "1234";
String inpw;

void setup() {
  lcd.begin(16, 2);
  lcd.print("Enter passwpord:");
  servo.attach(10);
  servo.write(0); //khoa dong
  pinMode(11, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(13, OUTPUT);
}

void loop() {
  char key = keypad.getKey();
  if (key == '*'){
    setPw();
    pw = inputPw();
  } else if (key =='#') {
    inpw = inputPw();
    if (inpw.equals(pw)) {
      lcd.clear();
      lcd.print("Open!");
      digitalWrite(13, HIGH);//led xanh bat
      delay(1000);
      digitalWrite(13, LOW);
      openLock();
    } else {
      lockMessage();
    }
  }
}

void openLock(){
  for (pos = 0; pos <= 90; pos +=1) {
    servo.write(pos);
    delay(15);
  }
  delay(5000);// open 5s
  for (pos = 90; pos >= 0; pos -= 1) {
    servo.write(pos);
    delay(15);
  }
}

String inputPw() {
  lcd.setCursor(5, 1);
  lcd.print("[____]");
  lcd.setCursor(6, 1);
  String result = "";
  while (result.length() < 4) {
    char key = keypad.getKey();
    if (key >= '0' && key <= '9') {
      lcd.print('*');
      result += key;
    }
  }
  return result;
}

bool setPw() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Enter New password:");
  String newpw = inputPw();

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Confirm password:");
  String confirmpw = inputPw();

  if (newpw.equals(confirmpw)) {
    lcd.print("Password updated!")
    return true;
  } else {
    lcd.clear();
    lcd.setCursor(0, 1);
    lcd.print("code mismatch");
    delay(200);
    return false;
  }
}

void lockMessage() {
  lcd.clear();
  lcd.print("Wrong!");
  digitalWrite(12, HIGH);//buzzer bật
  digitalWrite(11, HIGH);//led do bat
  delay(1000);
  tone(12, 100, 1000);
  digitalWrite(12, LOW);
  digitalWrite(11, LOW);
  inpw = "";//xoa pw khi nhap sai
}