source: trunk/www.guidonia.net/wp/wp-content/plugins/ferdinand-wordbook/bbcode.php@ 44

<?php

class bbcode{
    var $tags;
    var $settings;
    function bbcode(){
        $this->tags = array();
        $this->settings = array('enced'=>true);
    }
    function get_data($name,$cfa = ''){
        if(!array_key_exists($name,$this->tags)) return '';
        $data = $this->tags[$name];
        if($cfa) $sbc = $cfa; else $sbc = $name;
        if(!is_array($data)){
            $data = preg_replace('/^ALIAS(.+)$/','$1',$data);
            return $this->get_data($data,$sbc);
        }else{
            $data['Name'] = $sbc;
            return $data;
        }
    }
    function change_setting($name,$value){
        $this->settings[$name] = $value;
    }
    function add_alias($name,$aliasof){
        if(!array_key_exists($aliasof,$this->tags) or array_key_exists($name,$this->tags)) return false;
        $this->tags[$name] = 'ALIAS'.$aliasof;
        return true;
    }
    function onparam($param,$regexarray){
        $param = replace_pcre_array($param,$regexarray);
        if(!$this->settings['enced']){
            $param = htmlentities($param);
        }
        return $param;
    }
    function export_definition(){
        return serialize($this->tags);
    }
    function import_definiton($definition,$mode = 'append'){
        switch($mode){
            case 'append':
            $array = unserialize($definition);
            $this->tags = $array + $this->tags;
            break;
            case 'prepend':
            $array = unserialize($definition);
            $this->tags = $this->tags + $array;
            break;
            case 'overwrite':
            $this->tags = unserialize($definition);
            break;
            default:
            return false;
        }
        return true;
    }
    function add_tag($params){
        if(!is_array($params)) return 'Paramater array not an array.';
        if(!array_key_exists('Name',$params) or empty($params['Name'])) return 'Name parameter is required.';
        if(preg_match('/[^A-Za-z]/',$params['Name'])) return 'Name can only contain letters.';
        if(!array_key_exists('HasParam',$params)) $params['HasParam'] = false;
        if(!array_key_exists('HtmlBegin',$params)) return 'HtmlBegin paremater not specified!';
        if(!array_key_exists('HtmlEnd',$params)){
             if(preg_match('/^(<[A-Za-z]>)+$/',$params['HtmlBegin'])){
                 $params['HtmlEnd'] = begtoend($params['HtmlBegin']);
             }else{
                 return 'You didn\'t specify the HtmlEnd parameter, and your HtmlBegin parameter is too complex to change to an HtmlEnd parameter.  Please specify HtmlEnd.';
             }
        }
        if(!array_key_exists('ParamRegexReplace',$params)) $params['ParamRegexReplace'] = array();
        if(!array_key_exists('ParamRegex',$params)) $params['ParamRegex'] = '[^\\]]+';
        if(!array_key_exists('HasEnd',$params)) $params['HasEnd'] = true;
        if(array_key_exists($params['Name'],$this->tags)) return 'The name you specified is already in use.';
        $this->tags[$params['Name']] = $params;
        return '';
    }
    function parse_bbcode($text){
        foreach($this->tags as $tagname => $tagdata){
            if(!is_array($tagdata)) $tagdata = $this->get_data($tagname);
            $startfind = "/\\[{$tagdata['Name']}";
            if($tagdata['HasParam']){
                $startfind.= '=('.$tagdata['ParamRegex'].')';
            }
            $startfind.= '\\]/';
            if($tagdata['HasEnd']){
                $endfind = "[/{$tagdata['Name']}]";
                $starttags = preg_match_all($startfind,$text,$ignore);
                $endtags = substr_count($text,$endfind);
                if($endtags < $starttags){
                    $text.= str_repeat($endfind,$starttags - $endtags);
                }
                $text = str_replace($endfind,$tagdata['HtmlEnd'],$text);
            }
            $replace = str_replace(array('%%P%%','%%p%%'),'\'.$this->onparam(\'$1\',$tagdata[\'ParamRegexReplace\']).\'','\''.$tagdata['HtmlBegin'].'\'');
            $text = preg_replace($startfind.'e',$replace,$text);
        }
        return $text;
    }
} 
?>