public async Task SaveAsync(GraphViewModel item)
        {
            if (!Directory.Exists(StoragePath))
            {
                Directory.CreateDirectory(StoragePath);
            }

            var dto = item.ToDto();

            _container.Resolve <StateHub>().Save(dto);
            var json = JsonConvert.SerializeObject(dto);
            var path = GetFilePath(dto.Id);

            File.WriteAllText(path, json);
        }