// #include <WiFi.h>
// #include <Keypad.h>
// #include <LiquidCrystal_I2C.h>
// #include <ESP32Servo.h>

// char ssid[] = "Wokwi-GUEST";
// char password[] = "";

// Servo servo;
// LiquidCrystal_I2C lcd(0x27, 16, 2);

// const byte ROWS = 4;
// const byte COLS = 4;
// char hexaKeys[ROWS][COLS] = {
//   { '1', '2', '3', 'A' },
//   { '4', '5', '6', 'B' },
//   { '7', '8', '9', 'C' },
//   { '*', '0', '#', 'D' }
// };
// byte rowPins[ROWS] = { 12, 14, 27, 26 };
// byte colPins[COLS] = { 25, 33, 32, 35 };
// Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);

// #define BUZZER 15
// #define trigPin 23
// #define echoPin 19
// String otp =  "5555";

// long distance;

// void setup() {
//   Serial.begin(115200);
//   Serial.println("hello it is running");
//   lcd.init();
//   lcd.backlight();
//   lcd.clear();
//   lcd.print("CONNECTING TO...");
//   lcd.setCursor(0, 1);
//   lcd.print(ssid);
//   delay(1000);

//   WiFi.begin(ssid, password);
//   Serial.print("Connecting to WiFi ..");
//   while (WiFi.status() != WL_CONNECTED) {
//     Serial.print('.');
//     delay(500);
//   }

//   lcd.clear();
//   lcd.print(" WIFI CONNECTED ");
//   Serial.println(" WIFI CONNECTED ");

//   pinMode(BUZZER, OUTPUT);
//   pinMode(trigPin, OUTPUT);
//   pinMode(echoPin, INPUT);

//   lcd.clear();
//   lcd.print(" WIFI CONNECTED ");
//   delay(2000);

//   servo.attach(4);
//   servo.write(90);
//   delay(500);
// }

// void loop() {
//   lcd.setCursor(0, 0);
//   lcd.print(" OTP BASED DOOR ");
//   lcd.setCursor(0, 1);
//   lcd.print(" LOCK USING IOT ");

//   // Check if someone is near the door using ultrasonic sensor
//   measureDistance();

//   if (distance <= 200) {
//     activateAlarm();
//   } else {
//     deactivateAlarm();
//   }



//   if (digitalRead(customKeypad.getKey()) == LOW) {
//     int otp = random(2000, 9999);
//     String otpstring = String(otp);
//     Serial.println(otpstring);

//     lcd.clear();
//     lcd.setCursor(0, 0);
//     lcd.print("OTP SENT TO YOUR");
//     lcd.setCursor(0, 1);
//     lcd.print(" EMAIL AND IOT ");
//     delay(3000);

//     Serial.print("OTP is ");
//     Serial.println(otpstring);
//     delay(100);

//     lcd.clear();
//     lcd.setCursor(0, 0);
//     lcd.print("Enter OTP :");
//     getotp();
//   }

// }

// void measureDistance() {
//   digitalWrite(trigPin, LOW);
//   delayMicroseconds(2);
//   digitalWrite(trigPin, HIGH);
//   delayMicroseconds(10);
//   digitalWrite(trigPin, LOW);

//   distance = pulseIn(echoPin, HIGH) * 0.034 / 2; // Calculate distance in cm
// }

// void getotp() {
//   String enteredOTP = "";
//   while (enteredOTP.length() < 4) {
//     char customKey = customKeypad.getKey();
//     if (customKey) {
//       lcd.setCursor(0, 1);
//       enteredOTP += customKey;
//       lcd.print('*');
//     }
//   }

//   Serial.print("Entered OTP is ");
//   Serial.println(enteredOTP);

//   if (enteredOTP == String(otp)) {
//     lcd.clear();
//     lcd.print("Access Granted");
//     lcd.setCursor(0, 1);
//     lcd.print("Door Opening");
//     delay(2000);
//     lcd.clear();
//     lcd.print("* WELCOME *");

//     // Open the door
//     for (int i = 90; i >= 0; i--) {
//       servo.write(i);
//       delay(15);
//     }
//     delay(10000);
//     for (int i = 0; i <= 90; i++) {
//       servo.write(i);
//       delay(15);
//     }
//   } else {
//     lcd.clear();
//     lcd.print("Access Failed");
//     lcd.setCursor(0, 1);
//     lcd.print("Try Again !!!");

//     digitalWrite(BUZZER, HIGH);
//     delay(2000);
//     digitalWrite(BUZZER, LOW);
//     delay(3000);
//   }
// }

// void activateAlarm() {
//   digitalWrite(BUZZER, HIGH); // Turn on the buzzer
// }

// void deactivateAlarm() {
//   digitalWrite(BUZZER, LOW); // Turn off the buzzer
// }
#include <WiFi.h>
#include <Keypad.h>
#include <LiquidCrystal_I2C.h>
#include <ESP32Servo.h>

char ssid[] = "Wokwi-GUEST";
char password[] = "";

Servo servo;
LiquidCrystal_I2C lcd(0x27, 16, 2);

const byte ROWS = 4;
const byte COLS = 4;
char hexaKeys[ROWS][COLS] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};
byte rowPins[ROWS] = { 12, 14, 27, 26 };
byte colPins[COLS] = { 25, 33, 32, 35 };
Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);

#define BUZZER 15
#define trigPin 23
#define echoPin 19
String otp = "5555";

long distance;

void setup() {
  Serial.begin(115200);
  Serial.println("Initializing...");

  lcd.init();
  lcd.backlight();
  lcd.clear();
  lcd.print("CONNECTING TO...");
  lcd.setCursor(0, 1);
  lcd.print(ssid);
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println("WiFi Connected!");
  lcd.clear();
  lcd.print("WiFi Connected!");

  pinMode(BUZZER, OUTPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);

  servo.attach(4); // Attach servo to GPIO 4
  servo.write(90); // Set servo to initial position
}

void loop() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("OTP BASED DOOR");
  lcd.setCursor(0, 1);
  lcd.print("LOCK USING IOT");

  // Check if someone is near the door using ultrasonic sensor
  measureDistance();

  if (distance <= 200) {
    activateAlarm();
  } else {
    deactivateAlarm();
  }

  char key = customKeypad.getKey();
  if (key) {
    if (isDigit(key) || key == '*') {
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Enter OTP:");
      getotp();
    }
  }
}

void measureDistance() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  distance = pulseIn(echoPin, HIGH) * 0.034 / 2; // Calculate distance in cm
}

void getotp() {
  String enteredOTP = "";
  while (enteredOTP.length() < 4) {
    char customKey = customKeypad.getKey();
    if (customKey && (isDigit(customKey) || customKey == '*')) {
      lcd.setCursor(enteredOTP.length(), 1);
      lcd.print('*');
      enteredOTP += customKey;
    }
  }

  Serial.print("Entered OTP is ");
  Serial.println(enteredOTP);

  if (enteredOTP == otp) {
    lcd.clear();
    lcd.print("Access Granted");
    lcd.setCursor(0, 1);
    lcd.print("Door Opening");
    delay(2000);
    lcd.clear();
    lcd.print("* WELCOME *");

    // Open the door
    for (int i = 90; i >= 0; i--) {
      servo.write(i);
      delay(15);
    }
    delay(10000);
    for (int i = 0; i <= 90; i++) {
      servo.write(i);
      delay(15);
    }
  } else {
    lcd.clear();
    lcd.print("Access Failed");
    lcd.setCursor(0, 1);
    lcd.print("Try Again !!!");

    digitalWrite(BUZZER, HIGH);
    delay(2000);
    digitalWrite(BUZZER, LOW);
    delay(3000);
  }
}

void activateAlarm() {
  digitalWrite(BUZZER, HIGH); // Turn on the buzzer
}

void deactivateAlarm() {
  digitalWrite(BUZZER, LOW); // Turn off the buzzer
}