MS Word "save as HTML" and HTML Purifier

gistfile1.php

<?php
if ($_POST['q']){
        $dirty_html = $_POST['q'];
        if (!$dirty_html) {
                echo ('You must write some HTML!');
        } else {
                $config = HTMLPurifier_Config::createDefault();
                $config->set('Core', 'Encoding', 'ISO-8859-1');
                $config->set('HTML', 'Doctype', 'XHTML 1.0 Transitional');
                $config->set('HTML', 'TidyLevel', 'heavy');
                $config->set('Core','AcceptFullDocuments',true);
                $config->set('HTML', 'Allowed', 'a[href|title],em,p,blockquote,img');
               
                $purifier = new HTMLPurifier($config);
                $clean_html = $purifier->purify( $dirty_html );
                echo $clean_html;
        }
}
?>