/**
* Builds a facet and returns it as a renderable array.
*
* This method delegates to the relevant plugins to render a facet, it calls
* out to a widget plugin to do the actual rendering when results are found.
* When no results are found it calls out to the correct empty result plugin
* to build a render array.
*
* Before doing any rendering, the processors that implement the
* BuildProcessorInterface enabled on this facet will run.
*
* @param \Drupal\facets\FacetInterface $facet
* The facet we should build.
*
* @return array
* Facet render arrays.
*
* @throws \Drupal\facets\Exception\InvalidProcessorException
* Throws an exception when an invalid processor is linked to the facet.
*/
public function build(FacetInterface $facet)
{
// It might be that the facet received here, is not the same as the already
// loaded facets in the FacetManager.
// For that reason, get the facet from the already loaded facets in the
// FacetManager.
$facet = $this->facets[$facet->id()];
$facet_source_id = $facet->getFacetSourceId();
if ($facet->getOnlyVisibleWhenFacetSourceIsVisible()) {
// Block rendering and processing should be stopped when the facet source
// is not available on the page. Returning an empty array here is enough
// to halt all further processing.
$facet_source = $facet->getFacetSource();
if (!$facet_source->isRenderedInCurrentRequest()) {
return [];
}
}
// For clarity, process facets is called each build.
// The first facet therefor will trigger the processing. Note that
// processing is done only once, so repeatedly calling this method will not
// trigger the processing more than once.
$this->processFacets($facet_source_id);
// Get the current results from the facets and let all processors that
// trigger on the build step do their build processing.
// @see \Drupal\facets\Processor\BuildProcessorInterface.
// @see \Drupal\facets\Processor\WidgetOrderProcessorInterface.
$results = $facet->getResults();
$active_sorts = [];
// Load all processors, because getProcessorsByStage does not return the
// correct configuration for the processors.
// @todo: Fix when https://www.drupal.org/node/2722267 is fixed.
$processors = $facet->getProcessors();
foreach ($facet->getProcessorsByStage(ProcessorInterface::STAGE_BUILD) as $processor) {
/** @var \Drupal\facets\Processor\BuildProcessorInterface $build_processor */
$build_processor = $this->processorPluginManager->createInstance($processor->getPluginDefinition()['id'], ['facet' => $facet]);
if ($build_processor instanceof WidgetOrderProcessorInterface) {
// Sorting is handled last and together, to support nested sorts.
$active_sorts[] = $processors[$build_processor->getPluginId()];
} else {
if (!$build_processor instanceof BuildProcessorInterface) {
throw new InvalidProcessorException("The processor {$processor->getPluginDefinition()['id']} has a build definition but doesn't implement the required BuildProcessorInterface interface");
}
$results = $build_processor->build($facet, $results);
}
}
uasort($results, function ($a, $b) use($active_sorts) {
$return = 0;
foreach ($active_sorts as $sort) {
if ($return = $sort->sortResults($a, $b)) {
if ($sort->getConfiguration()['sort'] == 'DESC') {
$return *= -1;
}
break;
}
}
return $return;
});
$facet->setResults($results);
// No results behavior handling. Return a custom text or false depending on
// settings.
if (empty($facet->getResults())) {
$empty_behavior = $facet->getEmptyBehavior();
if ($empty_behavior['behavior'] == 'text') {
return [['#markup' => $empty_behavior['text']]];
} else {
return [];
}
}
// Let the widget plugin render the facet.
/** @var \Drupal\facets\Widget\WidgetInterface $widget */
$widget = $this->widgetPluginManager->createInstance($facet->getWidget());
return [$widget->build($facet)];
}
