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<?php
session_start();
include("SQL.php");
$DBConn = mysql_connect($SQLServ,$SQLUser,$SQLPass);
mysql_select_db($SQLDb,$DBConn);
?>
<html>
<head>
<link rel='stylesheet' type='text/css' href='style.css'/>
</head>
<body>
	<div id='container'>
		<div id='containerouter'>
			<div id='containerinner'>
				<p id='menu'>
					<?php
					include('header.php');
					?>
				</p>
			</div>
		</div>
		<div id='containerouter'>
			<div id='containerinner'>
			<h2>Register</h2>
			<table align='center'>
			<form id='register' action='' method='POST'>
			<tr><td>Username : </td><td><input type='text' name='username'/></td></tr>
			<tr><td>Password : </td><td><input type='password' name='password'/></td></tr>
			<tr><td>E-Mail : </td><td><input type='text' name='email'/></td></tr>
			<tr><td colspan='2'><center><input type='submit' name='submit_register' value='Register !'/></center></td></tr>
			</form>
			</table>
			</div>
		</div>
	</div>
</body>
</html>
<?php
		function checkText($text){
		return preg_match('/^[a-zA-Z0-9]+$/',$text) ? TRUE : FALSE;
		}
		function checkEmail($email){
		return preg_match('/^\S+@[\w\d.-]{2,}\.[\w]{2,6}$/iU', $email) ? TRUE : FALSE;
		}
		if(isset($_POST["submit_register"])){
			$username = mysql_real_escape_string($_POST["username"]);
			$password = mysql_real_escape_string($_POST["password"]);
			$email = mysql_real_escape_string($_POST["email"]);
			$UserCheck = mysql_fetch_array(mysql_query("SELECT * FROM users WHERE username='".$username."'")) or die(mysql_error());
			if($UserCheck['username']==$username)
				{
					echo "<div id='formErrors'><center>There is already an account with that username !</center></div>";
					exit();
				}
			$EmailCheck = mysql_fetch_array(mysql_query("SELECT * FROM users WHERE email='".$email."'"));
			if($EmailCheck['email']==$email)
				{
					echo "<div id='formErrors'><center>There is already an account with that e-mail address !</center></div>";
					exit();
				}
			if(checkText($username)==FALSE)
				{
					echo "<div id='formErrors'><center>Username is invalid !</center></div>";
					exit();
				}
			if(checkEmail($email)==FALSE)
				{
					echo "<div id='formErrors'><center>E-Mail is invalid !</center></div>";
					exit();
				}
			$lastuid = mysql_fetch_array(mysql_query("SELECT uid FROM users ORDER BY uid desc")) or die(mysql_error());
			$uid = $lastuid[0]+1;
			mysql_query("INSERT INTO users VALUES ('".$uid."','".$username."','".$password."','".$email."','0')") or die(mysql_error());
			echo "<div id='formErrors'><center><font color='green'>Successfully registered !</font></center></div>";
		}
?>