public function contents()
 {
     $optional = $this->context->msg('translate-optional')->escaped();
     $this->doLinkBatch();
     $sourceLang = Language::factory($this->group->getSourceLanguage());
     $targetLang = Language::factory($this->collection->getLanguage());
     $titleMap = $this->collection->keys();
     $output = '';
     $this->collection->initMessages();
     // Just to be sure
     /**
      * @var TMessage $m
      */
     foreach ($this->collection as $key => $m) {
         $tools = array();
         /**
          * @var Title $title
          */
         $title = $titleMap[$key];
         $original = $m->definition();
         $translation = $m->translation();
         $hasTranslation = $translation !== null;
         if ($hasTranslation) {
             $message = $translation;
             $extraAttribs = self::getLanguageAttributes($targetLang);
         } else {
             $message = $original;
             $extraAttribs = self::getLanguageAttributes($sourceLang);
         }
         Hooks::run('TranslateFormatMessageBeforeTable', array(&$message, $m, $this->group, $targetLang, &$extraAttribs));
         // Using Html::element( a ) because Linker::link is memory hog.
         // It takes about 20 KiB per call, and that times 5000 is quite
         // a lot of memory.
         $niceTitle = htmlspecialchars($this->context->getLanguage()->truncate($title->getPrefixedText(), -35));
         $linkAttribs = array('href' => $title->getLocalUrl(array('action' => 'edit')));
         $linkAttribs += TranslationEditPage::jsEdit($title, $this->group->getId());
         $tools['edit'] = Html::element('a', $linkAttribs, $niceTitle);
         $anchor = 'msg_' . $key;
         $anchor = Xml::element('a', array('id' => $anchor, 'href' => "#{$anchor}"), "↓");
         $extra = '';
         if ($m->hasTag('optional')) {
             $extra = '<br />' . $optional;
         }
         $tqeData = $extraAttribs + array('data-title' => $title->getPrefixedText(), 'data-group' => $this->group->getId(), 'id' => 'tqe-anchor-' . substr(sha1($title->getPrefixedText()), 0, 12), 'class' => 'tqe-inlineeditable ' . ($hasTranslation ? 'translated' : 'untranslated'));
         $button = $this->getReviewButton($m);
         $status = $this->getReviewStatus($m);
         $leftColumn = $button . $anchor . $tools['edit'] . $extra . $status;
         if ($this->reviewMode) {
             $output .= Xml::tags('tr', array('class' => 'orig'), Xml::tags('td', array('rowspan' => '2'), $leftColumn) . Xml::tags('td', self::getLanguageAttributes($sourceLang), TranslateUtils::convertWhiteSpaceToHTML($original)));
             $output .= Xml::tags('tr', null, Xml::tags('td', $tqeData, TranslateUtils::convertWhiteSpaceToHTML($message)));
         } else {
             $output .= Xml::tags('tr', array('class' => 'def'), Xml::tags('td', null, $leftColumn) . Xml::tags('td', $tqeData, TranslateUtils::convertWhiteSpaceToHTML($message)));
         }
         $output .= "\n";
     }
     return $output;
 }