Pressbooks\Book::getSubsections PHP Метод

    static function getSubsections($id)
    {
        libxml_use_internal_errors(true);
        $parent = get_post($id);
        $type = $parent->post_type;
        $output = array();
        $s = 1;
        $content = mb_convert_encoding(apply_filters('the_content', $parent->post_content), 'HTML-ENTITIES', 'UTF-8');
        if (empty($content)) {
            return false;
        }
        $doc = new \DOMDocument();
        $doc->loadHTML($content);
        $sections = $doc->getElementsByTagName('h1');
        foreach ($sections as $section) {
            $output[$type . '-' . $id . '-section-' . $s] = $section->textContent;
            $s++;
        }
        $errors = libxml_get_errors();
        // TODO: Handle errors gracefully
        libxml_clear_errors();
        if (empty($output)) {
            return false;
        }
        return $output;
    }

 /**
  * Uses $this->manifest to generate itself.
  *
  * @param array $book_contents
  * @param array $metadata
  */
 protected function createToc($book_contents, $metadata)
 {
     $vars = array('post_title' => '', 'stylesheet' => $this->stylesheet, 'post_content' => '', 'isbn' => @$metadata['pb_ebook_isbn']);
     $options = get_option('pressbooks_theme_options_global');
     // Start by inserting self into correct manifest position
     $array_pos = $this->positionOfToc();
     $file_id = 'table-of-contents';
     $filename = "{$file_id}.{$this->filext}";
     $vars['post_title'] = __('Table Of Contents', 'pressbooks');
     $this->manifest = array_slice($this->manifest, 0, $array_pos + 1, true) + array($file_id => array('ID' => -1, 'post_title' => $vars['post_title'], 'filename' => $filename)) + array_slice($this->manifest, $array_pos + 1, count($this->manifest) - 1, true);
     // HTML
     $li_count = 0;
     $i = 1;
     $html = '<div id="toc"><h1>' . __('Contents', 'pressbooks') . '</h1><ul>';
     foreach ($this->manifest as $k => $v) {
         // We only care about front-matter, part, chapter, back-matter
         // Skip the rest
         $subtitle = '';
         $author = '';
         $license = '';
         $title = Sanitize\strip_br($v['post_title']);
         if (preg_match('/^front-matter-/', $k)) {
             $class = 'front-matter ';
             $class .= \PressBooks\Taxonomy\front_matter_type($v['ID']);
             $subtitle = trim(get_post_meta($v['ID'], 'pb_subtitle', true));
             $author = trim(get_post_meta($v['ID'], 'pb_section_author', true));
             $license = $options['copyright_license'] ? get_post_meta($v['ID'], 'pb_section_license', true) : '';
         } elseif (preg_match('/^part-/', $k)) {
             $class = 'part';
             if (get_post_meta($v['ID'], 'pb_part_invisible', true) == 'on') {
                 $class .= ' display-none';
             }
         } elseif (preg_match('/^chapter-/', $k)) {
             $class = 'chapter';
             $class .= \PressBooks\Taxonomy\chapter_type($v['ID']);
             $subtitle = trim(get_post_meta($v['ID'], 'pb_subtitle', true));
             $author = trim(get_post_meta($v['ID'], 'pb_section_author', true));
             $license = $options['copyright_license'] ? get_post_meta($v['ID'], 'pb_section_license', true) : '';
             if ($this->numbered && \PressBooks\Taxonomy\chapter_type($v['ID']) !== 'numberless') {
                 $title = " {$i}. " . $title;
             }
             if (\PressBooks\Taxonomy\chapter_type($v['ID']) !== 'numberless') {
                 ++$i;
             }
         } elseif (preg_match('/^back-matter-/', $k)) {
             $class = 'back-matter ';
             $class .= \PressBooks\Taxonomy\back_matter_type($v['ID']);
             $subtitle = trim(get_post_meta($v['ID'], 'pb_subtitle', true));
             $author = trim(get_post_meta($v['ID'], 'pb_section_author', true));
             $license = $options['copyright_license'] ? get_post_meta($v['ID'], 'pb_section_license', true) : '';
         } else {
             continue;
         }
         $html .= sprintf('<li class="%s"><a href="%s"><span class="toc-chapter-title">%s</span>', $class, $v['filename'], Sanitize\decode($title));
         if ($subtitle) {
             $html .= ' <span class="chapter-subtitle">' . Sanitize\decode($subtitle) . '</span>';
         }
         if ($author) {
             $html .= ' <span class="chapter-author">' . Sanitize\decode($author) . '</span>';
         }
         if ($license) {
             $html .= ' <span class="chapter-license">' . $license . '</span> ';
         }
         $html .= "</a>";
         if (\PressBooks\Export\Export::shouldParseSections() == true) {
             $sections = \PressBooks\Book::getSubsections($v['ID']);
             if ($sections) {
                 $s = 1;
                 $html .= '<ul class="sections">';
                 foreach ($sections as $section) {
                     $html .= '<li class="section"><a href="' . $v['filename'] . '#section-' . $s . '"><span class="toc-subsection-title">' . Sanitize\decode($section) . '</span></a></li>';
                     ++$s;
                 }
                 $html .= '</ul>';
             }
         }
         $html .= "</li>\n";
         ++$li_count;
     }
     if (0 == $li_count) {
         $html .= '<li></li>';
     }
     $html .= "</ul></div>\n";
     // Create file
     $vars['post_content'] = $html;
     file_put_contents($this->tmpDir . "/OEBPS/{$filename}", $this->loadTemplate($this->dir . '/templates/xhtml.php', $vars));
 }