<?php

if ( ! function_exists('word_censor'))
{
    function word_censor($str, $censored, $replacement = '')
    {
        if ( ! is_array($censored))
        {
            return $str;
        }

        $str = ' '.$str.' ';

        // \w, \b and a few others do not match on a unicode character
        // set for performance reasons. As a result words like über
        // will not match on a word boundary. Instead, we'll assume that
        // a bad word will be bookeneded by any of these characters.
        $delim = '[-_\'\"`(){}<>\[\]|!?@#%&,.:;^~*+=\/ 0-9\n\r\t]';

        foreach ($censored as $badword)
        {
            if ($replacement != '')
            {
                $str = preg_replace("/({$delim})(".str_replace('\*', '\w*?', preg_quote($badword, '/')).")({$delim})/i", "\\1{$replacement}\\3", $str);
            }
            else
            {
                $str = preg_replace("/({$delim})(".str_replace('\*', '\w*?', preg_quote($badword, '/')).")({$delim})/ie", "'\\1'.str_repeat('#', strlen('\\2')).'\\3'", $str);
            }
        }

        return trim($str);
    }
}


echo word_censor('Texto do comentario com um palavrao', array('palavrao'), '---');
echo "\n";
echo word_censor('Texto do comentario com um palavrao', array('palavrao'));