<?php
session_start();

include("connect.php");
if (isset($_SESSION['loggedin'])) {
    header('Location: ./index.php');
}
?>

<form method="POST" action="register.php">

    <ul>
        <li>
            Username: <input type="text" name="username" />
        </li>
        <li>
            Password: <input type="password" name="password" />
        </li>
        <li>
            Password verify: <input type="password" name="passwordverify" />
        </li>
        <li>
            Email: <input type="text" name="email" />
        </li>
        <li>
            <input type="submit" name="submit" value="Register"/>
        </li>
    </ul>
</form>
<?php
if (isset($_POST['submit'])) {
    if (isset($_POST['username']) && isset($_POST['password']) && isset($_POST['passwordverify']) && isset($_POST['email'])) {
        if ($_POST['password'] == $_POST['passwordverify']) {
            $username = strtolower(htmlspecialchars($_POST['username'], ENT_QUOTES, 'UTF-8'));
            $password = htmlspecialchars($_POST['password'], ENT_QUOTES, 'UTF-8');
            $email = htmlspecialchars($_POST['email'], ENT_QUOTES, 'UTF-8');
            $email = filter_var($email, FILTER_SANITIZE_EMAIL);
            if (!filter_var($email, FILTER_VALIDATE_EMAIL) === false) {
                $query = mysqli_query($con, "SELECT * FROM `users` WHERE email='" . $email . "'");
                $query1 = mysqli_query($con, "SELECT * FROM `users` WHERE username='" . mysqli_real_escape_string($con, $username) . "'");
                if (mysqli_num_rows($query) > 0) {
                    die("Korisnik sa tim emailom  postoji!");
                }
                if (mysqli_num_rows($query1) > 0) {
                    die("Korisnik sa tim usernameom postoji!");
                }
                if (strlen($username) >= 6 && strlen($password) >= 10) {
                    $password = password_hash($password, PASSWORD_DEFAULT, ['cost' => 14]);
                    $register = mysqli_query($con, "INSERT INTO `users` VALUES ('', '" . mysqli_real_escape_string($con, $username) . "', '$password', '$email')");
                    if ($register) {
                        echo "Uspesno ste se registrovali!";
                        sleep(2);
                        header("Location: ./login.php");
                    } else {
                        die("Nisam uspeo ubaciti u bazu");
                    }
                } else {
                    die("Korisnicko ime mora imati najmanje 6 karaktera, a sifra najmanje 10.");
                }
            } else {
                die("Email nije ispravan.");
            }
        } else {
            die("Sifre se ne podudaraju.");
        }
    } else {
        die("Sva polja su obavezna!");
    }
}