Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\Core\Plugin;
Chris@0: 
Chris@18: use Drupal\Component\Plugin\PluginHelper;
Chris@0: use Drupal\Component\Plugin\PluginManagerInterface;
Chris@0: use Drupal\Component\Plugin\LazyPluginCollection;
Chris@0: use Drupal\Core\DependencyInjection\DependencySerializationTrait;
Chris@0: 
Chris@0: /**
Chris@0:  * Provides a default plugin collection for a plugin type.
Chris@0:  *
Chris@0:  * A plugin collection usually stores multiple plugins, and is used to lazily
Chris@0:  * instantiate them. When only one plugin is needed, it is still best practice
Chris@0:  * to encapsulate all of the instantiation logic in a plugin collection. This
Chris@0:  * class can be used directly, or subclassed to add further exception handling
Chris@0:  * in self::initializePlugin().
Chris@0:  */
Chris@0: class DefaultSingleLazyPluginCollection extends LazyPluginCollection {
Chris@0:   use DependencySerializationTrait;
Chris@0: 
Chris@0:   /**
Chris@0:    * The manager used to instantiate the plugins.
Chris@0:    *
Chris@0:    * @var \Drupal\Component\Plugin\PluginManagerInterface
Chris@0:    */
Chris@0:   protected $manager;
Chris@0: 
Chris@0:   /**
Chris@0:    * An array of configuration to instantiate the plugin with.
Chris@0:    *
Chris@0:    * @var array
Chris@0:    */
Chris@0:   protected $configuration;
Chris@0: 
Chris@0:   /**
Chris@0:    * The instance ID used for this plugin collection.
Chris@0:    *
Chris@0:    * @var string
Chris@0:    */
Chris@0:   protected $instanceId;
Chris@0: 
Chris@0:   /**
Chris@0:    * Constructs a new DefaultSingleLazyPluginCollection object.
Chris@0:    *
Chris@0:    * @param \Drupal\Component\Plugin\PluginManagerInterface $manager
Chris@0:    *   The manager to be used for instantiating plugins.
Chris@0:    * @param string $instance_id
Chris@0:    *   The ID of the plugin instance.
Chris@0:    * @param array $configuration
Chris@0:    *   An array of configuration.
Chris@0:    */
Chris@0:   public function __construct(PluginManagerInterface $manager, $instance_id, array $configuration) {
Chris@0:     $this->manager = $manager;
Chris@0:     $this->addInstanceId($instance_id, $configuration);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   protected function initializePlugin($instance_id) {
Chris@0:     $this->set($instance_id, $this->manager->createInstance($instance_id, $this->configuration));
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getConfiguration() {
Chris@0:     $plugin = $this->get($this->instanceId);
Chris@18:     if (PluginHelper::isConfigurable($plugin)) {
Chris@0:       return $plugin->getConfiguration();
Chris@0:     }
Chris@0:     else {
Chris@0:       return $this->configuration;
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function setConfiguration($configuration) {
Chris@0:     $this->configuration = $configuration;
Chris@0:     $plugin = $this->get($this->instanceId);
Chris@18:     if (PluginHelper::isConfigurable($plugin)) {
Chris@0:       $plugin->setConfiguration($configuration);
Chris@0:     }
Chris@0:     return $this;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function addInstanceId($id, $configuration = NULL) {
Chris@0:     $this->instanceId = $id;
Chris@0:     // Reset the list of instance IDs since there can be only one.
Chris@0:     $this->instanceIDs = [];
Chris@0:     parent::addInstanceId($id, $configuration);
Chris@0:     if ($configuration !== NULL) {
Chris@0:       $this->setConfiguration($configuration);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0: }