class LocalActionManager

class LocalActionManager extends DefaultPluginManager implements LocalActionManagerInterface {
    
    /**
     * Provides some default values for all local action plugins.
     *
     * @var array
     */
    protected $defaults = [
        // The plugin id. Set by the plugin system based on the top-level YAML key.
'id' => NULL,
        // The static title for the local action.
'title' => '',
        // The weight of the local action.
'weight' => NULL,
        // (Required) the route name used to generate a link.
'route_name' => NULL,
        // Default route parameters for generating links.
'route_parameters' => [],
        // Associative array of link options.
'options' => [],
        // The route names where this local action appears.
'appears_on' => [],
        // Default class for local action implementations.
'class' => 'Drupal\\Core\\Menu\\LocalActionDefault',
    ];
    
    /**
     * An argument resolver object.
     *
     * @var \Symfony\Component\HttpKernel\Controller\ArgumentResolverInterface
     */
    protected $argumentResolver;
    
    /**
     * The request stack.
     *
     * @var \Symfony\Component\HttpFoundation\RequestStack
     */
    protected $requestStack;
    
    /**
     * The current route match.
     *
     * @var \Drupal\Core\Routing\RouteMatchInterface
     */
    protected $routeMatch;
    
    /**
     * The route provider to load routes by name.
     *
     * @var \Drupal\Core\Routing\RouteProviderInterface
     */
    protected $routeProvider;
    
    /**
     * The access manager.
     *
     * @var \Drupal\Core\Access\AccessManagerInterface
     */
    protected $accessManager;
    
    /**
     * The current user.
     *
     * @var \Drupal\Core\Session\AccountInterface
     */
    protected $account;
    
    /**
     * The plugin instances.
     *
     * @var \Drupal\Core\Menu\LocalActionInterface[]
     */
    protected $instances = [];
    
    /**
     * Constructs a LocalActionManager object.
     *
     * @param \Symfony\Component\HttpKernel\Controller\ArgumentResolverInterface $argument_resolver
     *   An object to use in resolving route arguments.
     * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
     *   The request stack.
     * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
     *   The current route match.
     * @param \Drupal\Core\Routing\RouteProviderInterface $route_provider
     *   The route provider.
     * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
     *   The module handler.
     * @param \Drupal\Core\Cache\CacheBackendInterface $cache_backend
     *   Cache backend instance to use.
     * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
     *   The language manager.
     * @param \Drupal\Core\Access\AccessManagerInterface $access_manager
     *   The access manager.
     * @param \Drupal\Core\Session\AccountInterface $account
     *   The current user.
     */
    public function __construct(ArgumentResolverInterface $argument_resolver, RequestStack $request_stack, RouteMatchInterface $route_match, RouteProviderInterface $route_provider, ModuleHandlerInterface $module_handler, CacheBackendInterface $cache_backend, LanguageManagerInterface $language_manager, AccessManagerInterface $access_manager, AccountInterface $account) {
        // Skip calling the parent constructor, since that assumes annotation-based
        // discovery.
        $this->factory = new ContainerFactory($this, 'Drupal\\Core\\Menu\\LocalActionInterface');
        $this->argumentResolver = $argument_resolver;
        $this->requestStack = $request_stack;
        $this->routeMatch = $route_match;
        $this->routeProvider = $route_provider;
        $this->accessManager = $access_manager;
        $this->moduleHandler = $module_handler;
        $this->account = $account;
        $this->alterInfo('menu_local_actions');
        $this->setCacheBackend($cache_backend, 'local_action_plugins:' . $language_manager->getCurrentLanguage()
            ->getId(), [
            'local_action',
        ]);
    }
    
    /**
     * {@inheritdoc}
     */
    protected function getDiscovery() {
        if (!isset($this->discovery)) {
            $yaml_discovery = new YamlDiscovery('links.action', $this->moduleHandler
                ->getModuleDirectories());
            $yaml_discovery->addTranslatableProperty('title', 'title_context');
            $this->discovery = new ContainerDerivativeDiscoveryDecorator($yaml_discovery);
        }
        return $this->discovery;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getTitle(LocalActionInterface $local_action) {
        $controller = [
            $local_action,
            'getTitle',
        ];
        $arguments = $this->argumentResolver
            ->getArguments($this->requestStack
            ->getCurrentRequest(), $controller);
        return call_user_func_array($controller, $arguments);
    }
    
    /**
     * {@inheritdoc}
     */
    public function getActionsForRoute($route_appears) {
        if (!isset($this->instances[$route_appears])) {
            $route_names = [];
            $this->instances[$route_appears] = [];
            // @todo - optimize this lookup by compiling or caching.
            foreach ($this->getDefinitions() as $plugin_id => $action_info) {
                if (in_array($route_appears, $action_info['appears_on'])) {
                    $plugin = $this->createInstance($plugin_id);
                    $route_names[] = $plugin->getRouteName();
                    $this->instances[$route_appears][$plugin_id] = $plugin;
                }
            }
            // Pre-fetch all the action route objects. This reduces the number of SQL
            // queries that would otherwise be triggered by the access manager.
            if (!empty($route_names)) {
                $this->routeProvider
                    ->getRoutesByNames($route_names);
            }
        }
        $links = [];
        $cacheability = new CacheableMetadata();
        $cacheability->addCacheContexts([
            'route',
        ]);
        
        /** @var \Drupal\Core\Menu\LocalActionInterface $plugin */
        foreach ($this->instances[$route_appears] as $plugin_id => $plugin) {
            $route_name = $plugin->getRouteName();
            $route_parameters = $plugin->getRouteParameters($this->routeMatch);
            $access = $this->accessManager
                ->checkNamedRoute($route_name, $route_parameters, $this->account, TRUE);
            $links[$plugin_id] = [
                '#theme' => 'menu_local_action',
                '#link' => [
                    'title' => $this->getTitle($plugin),
                    'url' => Url::fromRoute($route_name, $route_parameters),
                    'localized_options' => $plugin->getOptions($this->routeMatch),
                ],
                '#access' => $access,
                '#weight' => $plugin->getWeight(),
            ];
            $cacheability->addCacheableDependency($access)
                ->addCacheableDependency($plugin);
        }
        $cacheability->applyTo($links);
        return $links;
    }

}