<?php
namespace Yoast\WP\SEO\Generators\Schema;
use Yoast\WP\SEO\Config\Schema_IDs;
/**
* Returns schema Breadcrumb data.
*/
class Breadcrumb extends Abstract_Schema_Piece {
/**
* Determine if we should add a breadcrumb attribute.
*
* @return bool
*/
public function is_needed() {
if ( $this->context->indexable->object_type === 'unknown' ) {
return false;
}
if ( $this->context->indexable->object_type === 'system-page' && $this->context->indexable->object_sub_type === '404' ) {
return false;
}
return true;
}
/**
* Returns Schema breadcrumb data to allow recognition of page's position in the site hierarchy.
*
* @link https://developers.google.com/search/docs/data-types/breadcrumb
*
* @return bool|array Array on success, false on failure.
*/
public function generate() {
$breadcrumbs = $this->context->presentation->breadcrumbs;
$list_elements = [];
// In case of pagination, replace the last breadcrumb, because it only contains "Page [number]" and has no URL.
if (
(
$this->helpers->current_page->is_paged()
|| $this->context->indexable->number_of_pages > 1
) && (
// Do not replace the last breadcrumb on static post pages.
! $this->helpers->current_page->is_static_posts_page()
// Do not remove the last breadcrumb if only one exists (bugfix for custom paginated frontpages).
&& \count( $breadcrumbs ) > 1
)
) {
\array_pop( $breadcrumbs );
}
// Only output breadcrumbs that are not hidden.
$breadcrumbs = \array_filter( $breadcrumbs, [ $this, 'not_hidden' ] );
\reset( $breadcrumbs );
/*
* Check whether at least one of the breadcrumbs is broken.
* If so, do not output anything.
*/
foreach ( $breadcrumbs as $breadcrumb ) {
if ( $this->is_broken( $breadcrumb ) ) {
return false;
}
}
// Create the last breadcrumb.
$last_breadcrumb = \array_pop( $breadcrumbs );
$breadcrumbs[] = $this->format_last_breadcrumb( $last_breadcrumb );
// If this is a static front page, prevent nested pages from creating a trail.
if ( $this->helpers->current_page->is_home_static_page() ) {
// Check if we're dealing with a nested page.
if ( \count( $breadcrumbs ) > 1 ) {
// Store the breadcrumbs home variable before dropping the parent page from the Schema.
$breadcrumbs_home = $breadcrumbs[0]['text'];
$breadcrumbs = [ \array_pop( $breadcrumbs ) ];
// Make the child page show the breadcrumbs home variable rather than its own title.
$breadcrumbs[0]['text'] = $breadcrumbs_home;
}
}
$breadcrumbs = \array_filter( $breadcrumbs, [ $this, 'not_empty_text' ] );
$breadcrumbs = \array_values( $breadcrumbs );
// Create intermediate breadcrumbs.
foreach ( $breadcrumbs as $index => $breadcrumb ) {
$list_elements[] = $this->create_breadcrumb( $index, $breadcrumb );
}
return [
'@type' => 'BreadcrumbList',
'@id' => $this->context->canonical . Schema_IDs::BREADCRUMB_HASH,
'itemListElement' => $list_elements,
];
}
/**
* Returns a breadcrumb array.
*
* @param int $index The position in the list.
* @param array $breadcrumb The position in the list.
*
* @return array A breadcrumb listItem.
*/
private function create_breadcrumb( $index, $breadcrumb ) {
$crumb = [
'@type' => 'ListItem',
'position' => ( $index + 1 ),
'name' => $this->helpers->schema->html->smart_strip_tags( $breadcrumb['text'] ),
];
if ( ! empty( $breadcrumb['url'] ) ) {
$crumb['item'] = $breadcrumb['url'];
}
return $crumb;
}
/**
* Creates the last breadcrumb in the breadcrumb list, omitting the URL per Google's spec.
*
* @link https://developers.google.com/search/docs/data-types/breadcrumb
*
* @param array $breadcrumb The position in the list.
*
* @return array The last of the breadcrumbs.
*/
private function format_last_breadcrumb( $breadcrumb ) {
unset( $breadcrumb['url'] );
return $breadcrumb;
}
/**
* Tests if the breadcrumb is broken.
* A breadcrumb is considered broken:
* - when it is not an array.
* - when it has no URL or text.
*
* @param array $breadcrumb The breadcrumb to test.
*
* @return bool `true` if the breadcrumb is broken.
*/
private function is_broken( $breadcrumb ) {
// A breadcrumb is broken if it is not an array.
if ( ! \is_array( $breadcrumb ) ) {
return true;
}
// A breadcrumb is broken if it does not contain a URL or text.
if ( ! \array_key_exists( 'url', $breadcrumb ) || ! \array_key_exists( 'text', $breadcrumb ) ) {
return true;
}
return false;
}
/**
* Checks whether the breadcrumb is not set to be hidden.
*
* @param array $breadcrumb The breadcrumb array.
*
* @return bool If the breadcrumb should not be hidden.
*/
private function not_hidden( $breadcrumb ) {
return empty( $breadcrumb['hide_in_schema'] );
}
/**
* Checks whether the breadcrumb has a not empty text.
*
* @param array $breadcrumb The breadcrumb array.
*
* @return bool If the breadcrumb has a not empty text.
*/
private function not_empty_text( $breadcrumb ) {
return ! empty( $breadcrumb['text'] );
}
}