public async Task <IEnumerable <FolderDto> > GetFolderStructure()
        {
            var folderDtos = (await _folderRepository.ReadTopFolders()).Select(f => new FolderDto
            {
                Id             = f.Id,
                Name           = f.Name,
                Children       = new List <FolderDto>(),
                Order          = f.Order,
                ParentFolderId = f.ParentFolderId
            }).OrderBy(f => f.Order);
            var folders = (await _folderRepository.ReadFolders()).Where(f => folderDtos.All(fd => fd.Id != f.Id));

            var structureDtos = new List <FolderDto>();

            foreach (var folderDto in folderDtos)
            {
                structureDtos.Add(await ConvertChildFolders(folderDto, folders));
            }

            return(structureDtos);
        }