doc/dev/plugins/breadcrumbs/classes/plugin/Breadcrumbs.php

123 lines
3.4 KiB
PHP

<?php
namespace Grav\Plugin\Breadcrumbs;
use Grav\Common\Grav;
class Breadcrumbs
{
/**
* @var array
*/
protected $breadcrumbs;
/**
* @var array
*/
protected $config;
/**
* @param $config
*/
public function __construct($config)
{
$this->config = $config;
}
/**
* Return an array of breadcrumbs for the current page.
*
* @return array An array of breadcrumbs.
*/
public function get()
{
// If the breadcrumbs have not yet been generated...
if (!$this->breadcrumbs) {
// Generate them now.
$this->build();
}
return $this->breadcrumbs;
}
/**
* Build the array of breadcrumbs.
*
* The array is generated by starting at the current page and then climbing
* the hierarchy until the root is reached. The resulting crumbs are then
* stored in the $breadcrumbs instance variable.
*
* @internal
*/
protected function build()
{
// Used to hold the breadcrumbs as they are being generated.
$hierarchy = array();
$grav = Grav::instance();
$current = $grav['page'];
// If the page is not routable...
if (!$current) {
// Set up an empty array of crumbs.
$this->breadcrumbs = array();
return;
}
// If we are not at the root page...
if (!$current->root()) {
// If we are configured to include the current page...
if ($this->config['include_current']) {
// Place the current page in the hierarchy.
$hierarchy[$current->url()] = $current;
}
$current = $current->parent();
// As long as $current does not contain the root page...
while ($current && !$current->root()) {
// Get the frontmatter of the page.
$header = $current->header();
// Assume we may descend unless otherwise told.
$may_descend = true;
// If the frontmatter contains a value for $may_descend...
if(isset(
$header->breadcrumbs,
$header->breadcrumbs['may_descend']
)) {
// Get that value.
$may_descend = $header->breadcrumbs['may_descend'];
}
// Then, if breadcrumbs should stop at this page...
if ($may_descend === false) {
// Empty the $hierarchy.
$hierarchy = [];
}
// Place the current page in the hierarchy.
$hierarchy[$current->url()] = $current;
// Get the parent of the current page.
$current = $current->parent();
}
}
// If we are configured to include the home page...
if ($this->config['include_home']) {
// Get the home page.
$home = $grav['pages']->dispatch('/');
// If the home page isn't already in the hierarchy...
if ($home && !array_key_exists($home->url(), $hierarchy)) {
// Place the home page in the hierarchy.
$hierarchy[] = $home;
}
}
// Reverse the array of breadcrumbs, so that they are in descending
// order.
$this->breadcrumbs = array_reverse($hierarchy);
}
}