public FileResult GetBillPDF(int?orderId)
        {
            try
            {
                Logger.Debug("Request to GetBillPDF. Order id: {0}, User: {1}", orderId, User.Identity.Name);

                string fileType = "application/pdf";
                string fileName;
                string path;

                if (orderId == null || _rentService.GetOrder(orderId) == null)
                {
                    Logger.Debug("Wrong request. Order id is null or invalid.  Returned default PDF");
                    path = Server.MapPath("~/App_Data/Bills/default.pdf");
                    byte[] masF1 = System.IO.File.ReadAllBytes(path);
                    return(File(masF1, fileType, "default.pdf"));
                }

                var orderDto = _rentService.GetOrder(orderId);
                if (orderDto.RepairPrice > 0)
                {
                    fileName = "RepairBill_" + orderDto.Id + ".pdf";
                    path     = Server.MapPath("~/App_Data/Bills/Repairs/" + fileName);
                }
                else
                {
                    fileName = "Bill_" + orderDto.Id + ".pdf";
                    path     = Server.MapPath("~/App_Data/Bills/Orders/" + fileName);
                }
                if (_rentService.CreateBillPDF(orderDto, path))
                {
                    byte[] masS = System.IO.File.ReadAllBytes(path);
                    Logger.Debug("PDF creation success. Returned bill's PDF");

                    return(File(masS, fileType, fileName));
                }

                Logger.Debug("PDF creation failed. Returned default PDF");
                path = Server.MapPath("~/App_Data/Bills/default.pdf");
                byte[] masF2 = System.IO.File.ReadAllBytes(path);
                return(File(masF2, fileType, "default.pdf"));
            }
            catch (ValidationException)
            {
                return(null);
            }
            catch (FileNotFoundException)
            {
                return(null);
            }
        }