<?php
class SandBoxParser
{
  protected
    $parser = null;

  public function __construct(Parser $parser){
    $this->parser = $parser;
  }

  public function convertWikiText($wikiText, $wgTitle = ''){
    return $this->parser->parse($wikiText, $wgTitle);
  }
}

class Parser
{
  protected
    $options = null;

  public function __construct(ParserOptions $options){
    $this->options = $options;
  }

  public function parse($wikiText, $wgTitle){
    return '';
  }
}

class ParserOptions
{
  public static function initialiseFromUser($wgUser){
    $options = new ParserOptions;
    return $options;
  }
}


$parser   = new Parser(ParserOptions::initialiseFromUser($wgUser));
$sandbox  = new SandBoxParser($parser);
$content  = $sandbox->convertWikiText('text', 'title');