'.esc_html__('Table of content shortcode can be used only once on a page, this page is using the shortcode more than once. Please remove the extra table of content shortcodes for this warning to go away.', 'siteseo').'';
}
$options = get_option('siteseo_advanced_option_name', []);
$content = get_the_content();
if(empty($content)){
return;
}
$heading_type = (!empty($options['toc_heading_type']) ? $options['toc_heading_type'] : 'ul');
$dom = new DOMDocument();
$internalErrors = libxml_use_internal_errors(true);
$dom->preserveWhiteSpace = false;
$html = '';
if($dom->loadHTML('' . $content)){
$xpath = new DOMXPath($dom);
$heading_list = ['h1', 'h2', 'h3', 'h4', 'h5', 'h6'];
$headings_to_scan = [];
foreach($heading_list as $h){
if(!empty($options['toc_excluded_headings']) && is_array($options['toc_excluded_headings']) && in_array($h, $options['toc_excluded_headings'])){
continue;
}
$headings_to_scan[] = '//'.$h;
}
if(empty($headings_to_scan)){
return;
}
$headings_to_scan = implode('|', $headings_to_scan);
// The imploded string will look like this //h1|//h2|//h3|//h4|//h5|//h6
$headings = $xpath->query($headings_to_scan);
if(empty($headings)){
return;
}
$last_h = 0;
$open_ul = 0;
$html .= '
'.(!empty($options['toc_label']) ? esc_html($options['toc_label']) : esc_html__('Table of Content', 'siteseo')).'
';
$siteseo_toc_run = true;
}
return $html;
}
// Converts heading text content to ID to be used as link
function siteseo_title_to_id($title){
$id = trim(strip_tags($title));
$id = remove_accents($title);
$id = sanitize_title_with_dashes($id);
$id = urlencode($id);
return $id;
}
function siteseo_add_ids_to_headings($content){
if(empty($content)){
return $content;
}
// If the page does not have the shortcode then we don't need to update the id's in the heading.
if(!has_shortcode($content, 'siteseo_toc')){
return $content;
}
$dom = new DOMDocument();
$internalErrors = libxml_use_internal_errors(true);
$dom->preserveWhiteSpace = false;
$html = '';
if($dom->loadHTML('' . $content)){
$xpath = new DOMXPath($dom);
$headings = $xpath->query('//h1|//h2|//h3|//h4|//h5|//h6');
if(empty($headings)){
return;
}
foreach($headings as $heading){
$title = trim(strip_tags($heading->nodeValue));
$id = $heading->getAttribute('id');
if(!empty($id)){
continue;
}
if(empty($title)){
continue;
}
$id = siteseo_title_to_id($title);
$heading->setAttribute('id', $id);
}
$content = $dom->saveHTML($dom->documentElement);
}
return $content;
}