Untitled

<?php
include_once("global.php");
$message = '';

if($_SERVER['REQUEST_METHOD'] == "POST") {
    $username = $_POST['username'];
    $firstname = $_POST['firstname'];
    $secondname = $_POST['lastname'];
    $email = $_POST['email'];
    $password = $_POST['password'];
    $password2 = $_POST['password2'];

    if ((!$username) || (!$firstname) || (!$lastname) || (!$email) || (!$password) || (!$password2)){
        $message = 'Please fill in all fields in the form below';

    }else{
        if($password != $password2) {
            $message = 'Your passwords do not match.';
        }else {
            $username = preg_replace("#[^0-9a-z]#i", "", $username);
            $firstname = preg_replace("#[^0-9a-z]#i", "", $firstname);
            $lastname = preg_replace("#[^0-9a-z]#i", "", $lastname);
            $password = sha1($password);
            $email = mysql_real_escape_string($email);

            $user_query = mysql_query("SELECT username FROM members WHERE username='$username' LIMIT 1") or die ("Could not check username");
            $count_username = mysql_num_rows($user_query);

            $email_query = mysql_query("SELECT email FROM members WHERE email='$email' LIMIT 1") or die ("Could not check email");
            $count_email = mysql_num_rows($email_query);

            if($count_username > 0){
                $message = 'Your username is already in use';
            }else if($count_email > 0) {
                $message = 'Your email is already in use.';

            }else {
                $ip_address = $_SERVER['REMOTE_ADDR'];
                $query = mysql_query("INSERT INTO members (username, firstname, lastname, email, password, ip_address, sign_up_date) VALUES ('$username, $firstname, $lastname, $email, $password, ip_address, sign_up_date now())')") or die ("Could not insert data");
                    $member_id = mysql_insert_id();
                    mkdir("users/$member_id", 0755);
                    $message = 'You succesfully registered.';
            }
        }

    }


    }


?>


<html DOCTYPE>
<html>

<head>
    <title>Welcome to our website!</title>

    <!-- CSS Imports -->
    <link rel="stylesheet" href="css/style.css" />

</head>
<body>
<!-- Content -->
<div class="container center">
    <h1>Register to my website</h1>
    <p><?=$message;?><p>
    <form action="register.php" method="post"
      <input type="text" name="username" placeholder="Username" /></br>
      <input type="text" name="firstname" placeholder="First Name" /></br>
      <input type="text" name="lastname" placeholder="Last Name" /></br>
      <input type="text" name="email" placeholder="Email" /></br>
      <input type="password" name="password" placeholder="Password" /></br>
      <input type="password" name="password2" placeholder="Validate Password" /></br>
      <input type="submit" value="Register" />
    </form>

</div>


<!-- JS Imports -->

</body>
</html>