protected function coursecat_category(coursecat_helper $chelper, $coursecat, $depth) {
        // open category tag
        $classes = array('category');
        if (empty($coursecat->visible)) {
            $classes[] = 'dimmed_category';
        }
        if ($chelper->get_subcat_depth() > 0 && $depth >= $chelper->get_subcat_depth()) {
            // do not load content
            $categorycontent = '';
            $classes[] = 'notloaded';
            if ($coursecat->get_children_count() ||
                    ($chelper->get_show_courses() >= self::COURSECAT_SHOW_COURSES_COLLAPSED && $coursecat->get_courses_count())) {
                $classes[] = 'with_children';
                $classes[] = 'collapsed';
            }
        } else {
            // load category content
            $categorycontent = $this->coursecat_category_content($chelper, $coursecat, $depth);
            $classes[] = 'loaded';
            if (!empty($categorycontent)) {
                $classes[] = 'with_children';
                // Category content loaded with children.
                $this->categoryexpandedonload = true;
            }
        }

        // Make sure JS file to expand category content is included.
        $this->coursecat_include_js();

        $content = html_writer::start_tag('div', array(
            'class' => join(' ', $classes),
            'data-categoryid' => $coursecat->id,
            'data-depth' => $depth,
            'data-showcourses' => $chelper->get_show_courses(),
            'data-type' => self::COURSECAT_TYPE_CATEGORY,
        ));

        // category name
        $categoryname = $coursecat->get_formatted_name();
        $categoryname = html_writer::link(new moodle_url('/course/index.php',
                array('categoryid' => $coursecat->id)),
                $categoryname);
        if ($chelper->get_show_courses() == self::COURSECAT_SHOW_COURSES_COUNT
                && ($coursescount = $coursecat->get_courses_count())) {
            $categoryname .= html_writer::tag('span', ' ('. $coursescount.')',
                    array('title' => get_string('numberofcourses'), 'class' => 'numberofcourse'));
        }
        $content .= html_writer::start_tag('div', array('class' => 'info'));

        $content .= html_writer::tag(($depth > 1) ? 'h4' : 'h3', $categoryname, array('class' => 'categoryname'));
        $content .= html_writer::end_tag('div'); // .info

        // add category content to the output
        $content .= html_writer::tag('div', $categorycontent, array('class' => 'content'));

        $content .= html_writer::end_tag('div'); // .category

        // Return the course category tree HTML
        return $content;
    }