class WorkspaceManager

class WorkspaceManager implements WorkspaceManagerInterface {
    use StringTranslationTrait;
    
    /**
     * The current active workspace or FALSE if there is no active workspace.
     *
     * @var \Drupal\workspaces\WorkspaceInterface|false
     */
    protected $activeWorkspace;
    public function __construct(RequestStack $requestStack, EntityTypeManagerInterface $entityTypeManager, MemoryCacheInterface $entityMemoryCache, AccountProxyInterface $currentUser, StateInterface $state, LoggerInterface $logger, ClassResolverInterface $classResolver, WorkspaceAssociationInterface $workspaceAssociation, WorkspaceInformationInterface $workspaceInfo, array $negotiatorIds = []) {
    }
    
    /**
     * {@inheritdoc}
     */
    public function hasActiveWorkspace() {
        return $this->getActiveWorkspace() !== FALSE;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getActiveWorkspace() {
        if (!isset($this->activeWorkspace)) {
            $request = $this->requestStack
                ->getCurrentRequest();
            foreach ($this->negotiatorIds as $negotiator_id) {
                
                /** @var \Drupal\workspaces\Negotiator\WorkspaceIdNegotiatorInterface $negotiator */
                $negotiator = $this->classResolver
                    ->getInstanceFromDefinition($negotiator_id);
                if ($negotiator->applies($request)) {
                    if ($workspace_id = $negotiator->getActiveWorkspaceId($request)) {
                        
                        /** @var \Drupal\workspaces\WorkspaceInterface $negotiated_workspace */
                        $negotiated_workspace = $this->entityTypeManager
                            ->getStorage('workspace')
                            ->load($workspace_id);
                    }
                    // By default, 'view' access is checked when a workspace is activated,
                    // but it should also be checked when retrieving the currently active
                    // workspace.
                    if (isset($negotiated_workspace) && $negotiated_workspace->access('view')) {
                        // Notify the negotiator that its workspace has been selected.
                        $negotiator->setActiveWorkspace($negotiated_workspace);
                        $active_workspace = $negotiated_workspace;
                        break;
                    }
                }
            }
            // If no negotiator was able to provide a valid workspace, default to the
            // live version of the site.
            $this->activeWorkspace = $active_workspace ?? FALSE;
        }
        return $this->activeWorkspace;
    }
    
    /**
     * {@inheritdoc}
     */
    public function setActiveWorkspace(WorkspaceInterface $workspace) {
        $this->doSwitchWorkspace($workspace);
        // Set the workspace on the proper negotiator.
        $request = $this->requestStack
            ->getCurrentRequest();
        foreach ($this->negotiatorIds as $negotiator_id) {
            $negotiator = $this->classResolver
                ->getInstanceFromDefinition($negotiator_id);
            if ($negotiator->applies($request)) {
                $negotiator->setActiveWorkspace($workspace);
                break;
            }
        }
        return $this;
    }
    
    /**
     * {@inheritdoc}
     */
    public function switchToLive() {
        $this->doSwitchWorkspace(NULL);
        // Unset the active workspace on all negotiators.
        foreach ($this->negotiatorIds as $negotiator_id) {
            $negotiator = $this->classResolver
                ->getInstanceFromDefinition($negotiator_id);
            $negotiator->unsetActiveWorkspace();
        }
        return $this;
    }
    
    /**
     * Switches the current workspace.
     *
     * @param \Drupal\workspaces\WorkspaceInterface|null $workspace
     *   The workspace to set as active or NULL to switch out of the currently
     *   active workspace.
     *
     * @throws \Drupal\workspaces\WorkspaceAccessException
     *   Thrown when the current user doesn't have access to view the workspace.
     */
    protected function doSwitchWorkspace($workspace) {
        // If the current user doesn't have access to view the workspace, they
        // shouldn't be allowed to switch to it, except in CLI processes.
        if ($workspace && PHP_SAPI !== 'cli' && !$workspace->access('view')) {
            $this->logger
                ->error('Denied access to view workspace %workspace_label for user %uid', [
                '%workspace_label' => $workspace->label(),
                '%uid' => $this->currentUser
                    ->id(),
            ]);
            throw new WorkspaceAccessException('The user does not have permission to view that workspace.');
        }
        $this->activeWorkspace = $workspace ?: FALSE;
        // Clear the static entity cache for the supported entity types.
        $cache_tags_to_invalidate = array_map(function ($entity_type_id) {
            return 'entity.memory_cache:' . $entity_type_id;
        }, array_keys($this->workspaceInfo
            ->getSupportedEntityTypes()));
        $this->entityMemoryCache
            ->invalidateTags($cache_tags_to_invalidate);
        // Clear the static cache for path aliases. We can't inject the path alias
        // manager service because it would create a circular dependency.
        if (\Drupal::hasService('path_alias.manager')) {
            \Drupal::service('path_alias.manager')->cacheClear();
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function executeInWorkspace($workspace_id, callable $function) {
        
        /** @var \Drupal\workspaces\WorkspaceInterface $workspace */
        $workspace = $this->entityTypeManager
            ->getStorage('workspace')
            ->load($workspace_id);
        if (!$workspace) {
            throw new \InvalidArgumentException('The ' . $workspace_id . ' workspace does not exist.');
        }
        $previous_active_workspace = $this->getActiveWorkspace();
        $this->doSwitchWorkspace($workspace);
        $result = $function();
        $this->doSwitchWorkspace($previous_active_workspace);
        return $result;
    }
    
    /**
     * {@inheritdoc}
     */
    public function executeOutsideWorkspace(callable $function) {
        $previous_active_workspace = $this->getActiveWorkspace();
        $this->doSwitchWorkspace(NULL);
        $result = $function();
        $this->doSwitchWorkspace($previous_active_workspace);
        return $result;
    }
    
    /**
     * {@inheritdoc}
     */
    public function purgeDeletedWorkspacesBatch() {
        $deleted_workspace_ids = $this->state
            ->get('workspace.deleted', []);
        // Bail out early if there are no workspaces to purge.
        if (empty($deleted_workspace_ids)) {
            return;
        }
        $batch_size = Settings::get('entity_update_batch_size', 50);
        // Get the first deleted workspace from the list and delete the revisions
        // associated with it, along with the workspace association records.
        $workspace_id = reset($deleted_workspace_ids);
        $all_associated_revisions = [];
        foreach (array_keys($this->workspaceInfo
            ->getSupportedEntityTypes()) as $entity_type_id) {
            $all_associated_revisions[$entity_type_id] = $this->workspaceAssociation
                ->getAssociatedRevisions($workspace_id, $entity_type_id);
        }
        $all_associated_revisions = array_filter($all_associated_revisions);
        $count = 1;
        foreach ($all_associated_revisions as $entity_type_id => $associated_revisions) {
            
            /** @var \Drupal\Core\Entity\RevisionableStorageInterface $associated_entity_storage */
            $associated_entity_storage = $this->entityTypeManager
                ->getStorage($entity_type_id);
            // Sort the associated revisions in reverse ID order, so we can delete the
            // most recent revisions first.
            krsort($associated_revisions);
            // Get a list of default revisions tracked by the given workspace, because
            // they need to be handled differently than pending revisions.
            $initial_revision_ids = $this->workspaceAssociation
                ->getAssociatedInitialRevisions($workspace_id, $entity_type_id);
            foreach (array_keys($associated_revisions) as $revision_id) {
                if ($count > $batch_size) {
                    continue 2;
                }
                // If the workspace is tracking the entity's default revision (i.e. the
                // entity was created inside that workspace), we need to delete the
                // whole entity after all of its pending revisions are gone.
                if (isset($initial_revision_ids[$revision_id])) {
                    $associated_entity_storage->delete([
                        $associated_entity_storage->load($initial_revision_ids[$revision_id]),
                    ]);
                }
                else {
                    // Delete the associated entity revision.
                    $associated_entity_storage->deleteRevision($revision_id);
                }
                $count++;
            }
        }
        // The purging operation above might have taken a long time, so we need to
        // request a fresh list of tracked entities. If it is empty, we can go ahead
        // and remove the deleted workspace ID entry from state.
        $has_associated_revisions = FALSE;
        foreach (array_keys($this->workspaceInfo
            ->getSupportedEntityTypes()) as $entity_type_id) {
            if (!empty($this->workspaceAssociation
                ->getAssociatedRevisions($workspace_id, $entity_type_id))) {
                $has_associated_revisions = TRUE;
                break;
            }
        }
        if (!$has_associated_revisions) {
            unset($deleted_workspace_ids[$workspace_id]);
            $this->state
                ->set('workspace.deleted', $deleted_workspace_ids);
            // Delete any possible leftover association entries.
            $this->workspaceAssociation
                ->deleteAssociations($workspace_id);
        }
    }

}