wordpress like shortcode

gistfile1.php

<?php

class ShortCodeWidget extends COutputProcessor
{
    public $purifyOutput = false;

    private $codes;

    public function processOutput($output)
    {
        $dir = Yii::getPathOfAlias('ext.shortcodes');
        $files = CFileHelper::findFiles($dir);
        foreach ($files as $file) {
            include $file;
        }

        $output = $this->transform($output);
        if ($this->purifyOutput) {
            $purifier = new CHtmlPurifier;
            $output = $purifier->purify($output);
        }
        parent::processOutput($output);
    }
    
    function add($tag, $func)
    {
        if (is_callable($func)) {
            $this->codes[$tag] = $func;
        }
    }

    function transform($content)
    {
        if (empty($this->codes) || !is_array($this->codes)) {
            return $content;
        }

        $pattern = $this->getRegex();
        return preg_replace_callback("/$pattern/s", array($this, 'transformTag'), $content);
    }

    public function transformTag($m)
    {
        // allow [[foo]] syntax for escaping a tag
        if ( $m[1] == '[' && $m[6] == ']' ) {
            return substr($m[0], 1, -1);
        }

        $tag = $m[2];
        $attr = $this->parseAttributes($m[3]);

        if ( isset($m[5]) ) {
            // enclosing tag - extra parameter
            return $m[1] . call_user_func($this->codes[$tag], $attr, $m[5], $tag) . $m[6];
        } else {
            // self-closing tag
            return $m[1] . call_user_func($this->codes[$tag], $attr, null,  $tag) . $m[6];
        }
    }

    function parseAttributes($text)
    {
        $atts = array();
        $pattern = '/(w+)s*=s*"([^"]*)"(?:s|$)|(w+)s*=s*'([^']*)'(?:s|$)|(w+)s*=s*([^s'"]+)(?:s|$)|"([^"]*)"(?:s|$)|(S+)(?:s|$)/';
        $text = preg_replace("/[x{00a0}x{200b}]+/u", " ", $text);
        if (preg_match_all($pattern, $text, $match, PREG_SET_ORDER)) {
            foreach ($match as $m) {
                if (!empty($m[1]))
                    $atts[strtolower($m[1])] = stripcslashes($m[2]);
                elseif (!empty($m[3]))
                    $atts[strtolower($m[3])] = stripcslashes($m[4]);
                elseif (!empty($m[5]))
                    $atts[strtolower($m[5])] = stripcslashes($m[6]);
                elseif (isset($m[7]) and strlen($m[7]))
                    $atts[] = stripcslashes($m[7]);
                elseif (isset($m[8]))
                    $atts[] = stripcslashes($m[8]);
            }
        } else {
            $atts = ltrim($text);
        }
        return $atts;
    }

    function getRegex()
    {
        $tagnames  = array_keys($this->codes);
        $tagregexp = join('|', array_map('preg_quote', $tagnames));

        // WARNING! Do not change this regex without changing do_shortcode_tag() and strip_shortcode_tag()
        return
              '\['                              // Opening bracket
            . '(\[?)'                           // 1: Optional second opening bracket for escaping shortcodes: [[tag]]
            . "($tagregexp)"                     // 2: Shortcode name
            . '\b'                              // Word boundary
            . '('                                // 3: Unroll the loop: Inside the opening shortcode tag
            .     '[^\]\/]*'                   // Not a closing bracket or forward slash
            .     '(?:'
            .         '\/(?!\])'               // A forward slash not followed by a closing bracket
            .         '[^\]\/]*'               // Not a closing bracket or forward slash
            .     ')*?'
            . ')'
            . '(?:'
            .     '(\/)'                        // 4: Self closing tag ...
            .     '\]'                          // ... and closing bracket
            . '|'
            .     '\]'                          // Closing bracket
            .     '(?:'
            .         '('                        // 5: Unroll the loop: Optionally, anything between the opening and closing shortcode tags
            .             '[^\[]*+'             // Not an opening bracket
            .             '(?:'
            .                 '\[(?!\/\2\])' // An opening bracket not followed by the closing shortcode tag
            .                 '[^\[]*+'         // Not an opening bracket
            .             ')*+'
            .         ')'
            .         '\[\/\2\]'             // Closing shortcode tag
            .     ')?'
            . ')'
            . '(\]?)';                          // 6: Optional second closing brocket for escaping shortcodes: [[tag]]
    }

}