class ShortcutSetStorage

class ShortcutSetStorage extends ConfigEntityStorage implements ShortcutSetStorageInterface {
    
    /**
     * The module handler.
     *
     * @var \Drupal\Core\Extension\ModuleHandlerInterface
     */
    protected $moduleHandler;
    
    /**
     * The database connection.
     *
     * @var \Drupal\Core\Database\Connection
     */
    protected $connection;
    
    /**
     * Constructs a ShortcutSetStorageController object.
     *
     * @param \Drupal\Core\Entity\EntityTypeInterface $entity_info
     *   The entity info for the entity type.
     * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
     *   The config factory service.
     * @param \Drupal\Component\Uuid\UuidInterface $uuid_service
     *   The UUID service.
     * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
     *   The module handler.
     * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
     *   The language manager.
     * @param \Drupal\Core\Cache\MemoryCache\MemoryCacheInterface $memory_cache
     *   The memory cache.
     * @param \Drupal\Core\Database\Connection $connection
     *   The database connection.
     */
    public function __construct(EntityTypeInterface $entity_info, ConfigFactoryInterface $config_factory, UuidInterface $uuid_service, ModuleHandlerInterface $module_handler, LanguageManagerInterface $language_manager, MemoryCacheInterface $memory_cache, Connection $connection) {
        parent::__construct($entity_info, $config_factory, $uuid_service, $language_manager, $memory_cache);
        $this->moduleHandler = $module_handler;
        $this->connection = $connection;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_info) {
        return new static($entity_info, $container->get('config.factory'), $container->get('uuid'), $container->get('module_handler'), $container->get('language_manager'), $container->get('entity.memory_cache'), $container->get('database'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function deleteAssignedShortcutSets(ShortcutSetInterface $entity) {
        // First, delete any user assignments for this set, so that each of these
        // users will go back to using whatever default set applies.
        $this->connection
            ->delete('shortcut_set_users')
            ->condition('set_name', $entity->id())
            ->execute();
    }
    
    /**
     * {@inheritdoc}
     */
    public function assignUser(ShortcutSetInterface $shortcut_set, $account) {
        $current_shortcut_set = $this->getDisplayedToUser($account);
        $this->connection
            ->merge('shortcut_set_users')
            ->key('uid', $account->id())
            ->fields([
            'set_name' => $shortcut_set->id(),
        ])
            ->execute();
        if ($current_shortcut_set instanceof ShortcutSetInterface) {
            Cache::invalidateTags($current_shortcut_set->getCacheTagsToInvalidate());
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function unassignUser($account) {
        $current_shortcut_set = $this->getDisplayedToUser($account);
        $deleted = $this->connection
            ->delete('shortcut_set_users')
            ->condition('uid', $account->id())
            ->execute();
        if ($current_shortcut_set instanceof ShortcutSetInterface) {
            Cache::invalidateTags($current_shortcut_set->getCacheTagsToInvalidate());
        }
        return (bool) $deleted;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getAssignedToUser($account) {
        $query = $this->connection
            ->select('shortcut_set_users', 'ssu');
        $query->fields('ssu', [
            'set_name',
        ]);
        $query->condition('ssu.uid', $account->id());
        return $query->execute()
            ->fetchField();
    }
    
    /**
     * {@inheritdoc}
     */
    public function getDisplayedToUser(AccountInterface $account) : ShortcutSetInterface {
        if ($set_name = $this->getAssignedToUser($account)) {
            return $this->load($set_name);
        }
        return $this->getDefaultSet($account);
    }
    
    /**
     * {@inheritdoc}
     */
    public function countAssignedUsers(ShortcutSetInterface $shortcut_set) {
        return Database::getConnection()->query('SELECT COUNT(*) FROM {shortcut_set_users} WHERE [set_name] = :name', [
            ':name' => $shortcut_set->id(),
        ])
            ->fetchField();
    }
    
    /**
     * {@inheritdoc}
     */
    public function getDefaultSet(AccountInterface $account) {
        // Allow modules to return a default shortcut set name. Since we can only
        // have one, we allow the last module which returns a valid result to take
        // precedence. If no module returns a valid set, fall back on the site-wide
        // default, which is the lowest-numbered shortcut set.
        $suggestions = array_reverse($this->moduleHandler
            ->invokeAll('shortcut_default_set', [
            $account,
        ]));
        $suggestions[] = 'default';
        $shortcut_set = NULL;
        foreach ($suggestions as $name) {
            if ($shortcut_set = $this->load($name)) {
                break;
            }
        }
        return $shortcut_set;
    }

}