public ActionResult Reflect(string id, string type, string width, string idx)
        {
            // TODO validate parameters
            if (string.IsNullOrEmpty(width))
            {
                width = "0";
            }

            var userName      = User.Identity.Name;
            var shapesManager = new ShapesManager();
            var area          = shapesManager.RegisterShape(id, Int32.Parse(type), double.Parse(width),
                                                            Int32.Parse(idx), userName);

            return(Json(new { area = area.ToString() }));
        }