class MenuLinkDefault

class MenuLinkDefault extends MenuLinkBase implements ContainerFactoryPluginInterface {
  
  /**
   * {@inheritdoc}
   */
  protected $overrideAllowed = [
    'menu_name' => 1,
    'parent' => 1,
    'weight' => 1,
    'expanded' => 1,
    'enabled' => 1,
  ];
  
  /**
   * The static menu link service used to store updates to weight/parent etc.
   *
   * @var \Drupal\Core\Menu\StaticMenuLinkOverridesInterface
   */
  protected $staticOverride;
  
  /**
   * Constructs a new MenuLinkDefault.
   *
   * @param array $configuration
   *   A configuration array containing information about the plugin instance.
   * @param string $plugin_id
   *   The plugin ID for the plugin instance.
   * @param mixed $plugin_definition
   *   The plugin implementation definition.
   * @param \Drupal\Core\Menu\StaticMenuLinkOverridesInterface $static_override
   *   The static override storage.
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition, StaticMenuLinkOverridesInterface $static_override) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);
    $this->staticOverride = $static_override;
  }
  
  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static($configuration, $plugin_id, $plugin_definition, $container->get('menu_link.static.overrides'));
  }
  
  /**
   * {@inheritdoc}
   */
  public function getTitle() {
    return (string) $this->pluginDefinition['title'];
  }
  
  /**
   * {@inheritdoc}
   */
  public function getDescription() {
    return (string) $this->pluginDefinition['description'];
  }
  
  /**
   * {@inheritdoc}
   */
  public function isResettable() {
    // The link can be reset if it has an override.
    return (bool) $this->staticOverride
      ->loadOverride($this->getPluginId());
  }
  
  /**
   * {@inheritdoc}
   */
  public function getResetRoute() : Url {
    return Url::fromRoute('menu_ui.link_reset', [
      'menu_link_plugin' => $this->getPluginId(),
    ]);
  }
  
  /**
   * {@inheritdoc}
   */
  public function updateLink(array $new_definition_values, $persist) {
    // Filter the list of updates to only those that are allowed.
    $overrides = array_intersect_key($new_definition_values, $this->overrideAllowed);
    // Update the definition.
    $this->pluginDefinition = $overrides + $this->getPluginDefinition();
    if ($persist) {
      // Always save the menu name as an override to avoid defaulting to tools.
      $overrides['menu_name'] = $this->pluginDefinition['menu_name'];
      $this->staticOverride
        ->saveOverride($this->getPluginId(), $this->pluginDefinition);
    }
    return $this->pluginDefinition;
  }

}