BlockPluginCollection.php

<?php

namespace Drupal\ctools\Plugin;

use Drupal\Core\Block\BlockPluginInterface;
use Drupal\Core\Plugin\DefaultLazyPluginCollection;

/**
 * Provides a collection of block plugins.
 */
class BlockPluginCollection extends DefaultLazyPluginCollection {
    
    /**
     * {@inheritdoc}
     *
     * @return \Drupal\Core\Block\BlockPluginInterface
     */
    public function &get($instance_id) {
        return parent::get($instance_id);
    }
    
    /**
     * Returns all blocks keyed by their region.
     *
     * @return array
     *   An associative array keyed by region, containing an associative array of
     *   block plugins.
     */
    public function getAllByRegion() {
        $region_assignments = [];
        foreach ($this as $block_id => $block) {
            $configuration = $block->getConfiguration();
            $region = $configuration['region'] ?? NULL;
            $region_assignments[$region][$block_id] = $block;
        }
        foreach ($region_assignments as $region => $region_assignment) {
            // @todo Determine the reason this needs error suppression.
            @uasort($region_assignment, function (BlockPluginInterface $a, BlockPluginInterface $b) {
                $a_config = $a->getConfiguration();
                $a_weight = $a_config['weight'] ?? 0;
                $b_config = $b->getConfiguration();
                $b_weight = $b_config['weight'] ?? 0;
                if ($a_weight == $b_weight) {
                    return strcmp($a->label(), $b->label());
                }
                return $a_weight > $b_weight ? 1 : -1;
            });
            $region_assignments[$region] = $region_assignment;
        }
        return $region_assignments;
    }

}