public IEnumerable <InvoiceItemDto> GetByInvoiceId(int invoiceId)
        {
            var result       = _invoiceItemRepository.GetByInvoiceId(invoiceId);
            var mappedResult = _mapper.Map <IEnumerable <InvoiceItemDto> >(result);

            return(mappedResult);
        }
        public void DeleteInvoice(int invoiceId)
        {
            var invoiceItems = _invoiceItemRepository.GetByInvoiceId(invoiceId);

            if (invoiceItems != null)
            {
                foreach (var item in invoiceItems)
                {
                    _invoiceItemRepository.Delete(item);
                }
            }
            var invoice = _invoiceRepository.GetById(invoiceId);

            _invoiceRepository.Delete(invoice);
            _invoiceRepository.SaveChanges();
        }