public ActionResult SaveGroupImage(long groupId)
        {
            var group = RepositoryContext.DataRepository.Get<Group>(groupId, "VisualDetail");

            var file = Request.Files["ImageData"];
            using (var binaryReader = new BinaryReader(file.InputStream))
            {
                var fileData = binaryReader.ReadBytes(file.ContentLength);

                if (group.VisualDetail == null)
                {
                    GroupVisualDetail gvd = new GroupVisualDetail
                    {
                        ID = groupId,
                        ImageData = fileData,
                        ImageType = file.ContentType
                    };
                    RepositoryContext.DataRepository.Insert(gvd);
                }
                else
                {
                    group.VisualDetail.ImageData = fileData;
                    group.VisualDetail.ImageType = file.ContentType;
                    RepositoryContext.DataRepository.Save();
                }
            }
            return new EmptyResult();
        }