Untitled

<?php include_once("scripts/global.php");
$message = "";
if(isset($_POST['username'])){ }

	$username = $_POST['username'];
	$fname = $_POST['fname'];
	$lname = $_POST['lname'];
	$email = $_POST['email'];
	$pass1 = $_POST['pass1'];
	$pass2 = $_POST['pass2'];

	//error handeling
	if ((!$username)||(!$fname)||(!$lname)||(!$email)||(!$pass1)||(!$pass2)) {
		$message = "Please insert all fields in the form below";
	} else {
		if($pass1 != $pass2){
			$message= "Your password fields do not match";

		}else{
			//securing the data
			$username = preg_replace("#[^0-9a-z]#i","",$username);
			$fname = preg_replace("#[^0-9a-z]#i","",$fname);
			$lname = preg_replace("#[^0-9a-z]#i","",$lname);
			$pass1 = sha1($pass1);

			$email=mysql_real_escape_string($email);

			//check for duplicates
			$user_query=mysql_query("SELECT username FROM members WHERE username='$username'LIMT 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'LIMT 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("")or die("");
				$member_id=mysql_insert_id();
				mkdir("users/$member_id",0755);
				$message= "Register complete";
			}
		}
	}
?>
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>Untitled</title>
<link href="css/global.css" rel="stylesheet" type="text/css"/>
</head>
<body>
<div class="container center">
	<h1>Register</h1><br>
	<p><?php print("$message");?></p>
    <form action="register.php" method="post">
            <input type="text" name="username" placeholder="Username" /><br />
            <br /><input type="text" name="fname" placeholder="First name" /><br />
            <br /><input type="text" name="lname" placeholder="Last name" /><br />
            <br /><input type="text" name="email" placeholder="Email Address" /><br />
            <br /><input type="password" name="pass1" placeholder="Password" /><br />
            <br /><input type="password" name="pass2" placeholder="Validate Password" /><br />
            <br /><input type="submit" value="Submit" />
    </form>
    </div>
</body>
</html>