<?php

namespace Drupal\entity_browser;

use Drupal\Core\Cache\CacheBackendInterface;
use Drupal\Core\Extension\ModuleHandlerInterface;
use Drupal\Core\Plugin\DefaultPluginManager;

/**
 * Manages entity browser widget plugins.
 */
class WidgetManager extends DefaultPluginManager {

  /**
   * Constructs a new WidgetManager.
   *
   * @param \Traversable $namespaces
   *   An object that implements \Traversable which contains the root paths
   *   keyed by the corresponding namespace to look for plugin implementations.
   * @param \Drupal\Core\Cache\CacheBackendInterface $cache_backend
   *   Cache backend instance to use.
   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
   *   The module handler.
   */
  public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, ModuleHandlerInterface $module_handler) {
    parent::__construct('Plugin/EntityBrowser/Widget', $namespaces, $module_handler, 'Drupal\entity_browser\WidgetInterface', 'Drupal\entity_browser\Annotation\EntityBrowserWidget');

    $this->alterInfo('entity_browser_widget_info');
    $this->setCacheBackend($cache_backend, 'entity_browser_widget_plugins');
  }

  /**
   * {@inheritdoc}
   */
  protected function findDefinitions() {
    $definitions = parent::findDefinitions();

    // Our own "media_image_upload" widget should only be available if the
    // "Media" module is enabled.
    if (!$this->moduleHandler->moduleExists('media')) {
      unset($definitions['media_image_upload']);
    }

    return $definitions;
  }

}
