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<?php

/**
 * @author Jason
 * @copyright 2010
 */

include "connect.php";

$submit = $_POST['submit'];

$username = mysql_real_escape_string( htmlspecialchars( strip_tags( addslashes( $_POST['username'] ) ) ) );
$password = md5( mysql_real_escape_string( htmlspecialchars( strip_tags( addslashes( $_POST['password'] ) ) ) ) );
$repeatpassword = md5( mysql_real_escape_string( htmlspecialchars( strip_tags( addslashes( $_POST['repeatpassword'] ) ) ) ) );

    if( isset( $submit ) )
    {

        $query = mysql_query(" SELECT * FROM users WHERE username = '$username' ");
        $numrows = mysql_num_rows( $query );

        if ( $numrows )
        {
            echo "Username is taken!";
        }

            if ( $username && $password && $repeatpassword )
            {

                if ( strlen( $username )>25 )
                {
                    echo "Username must be within 25 characters!";
                }

                    if ( strlen( $password )>25 && strlen( $password )<4 )
                    {
                        echo "Password must be between 4 to 25 characters!";
                    }

            }
            else
            {
                echo "Please fill in all fields!";
            }

    }

?>

<html>

<form action='' method='POST'>

    Username: <input type="text" name="username"/><br />
    Password: <input type="password" name="password"/><br />
    Repeat Password: <input type="password" name="repeatpassword"/><br />

    <input type="submit" name="submit" value="Register"/>

</form>

</html>