private void DoResumableDownloadSingleThread()

in sdk/Common/ResumableDownloadManager.cs [80:144]
54 lines of code
10 McCabe index (conditional complexity)

        private void DoResumableDownloadSingleThread(DownloadObjectRequest request, ResumableDownloadContext resumableContext,
                                      EventHandler<StreamTransferProgressArgs> downloadProgressCallback)
        {
            _downloadedBytes = resumableContext.GetDownloadedBytes();
            if (!request.MatchingETagConstraints.Contains(resumableContext.ETag))
            {
                request.MatchingETagConstraints.Add(resumableContext.ETag);
            }

            long totalBytes = resumableContext.GetTotalBytes();
            foreach (var part in resumableContext.PartContextList)
            {
                if (part.IsCompleted)
                {
                    // is CRC is enabled and part.Crc64 is 0, then redownload the data
                    if (!_conf.EnableCrcCheck || part.Crc64 != 0)
                    {
                        continue;
                    }
                }

                using (Stream fs = File.Open(GetTempDownloadFile(request), FileMode.OpenOrCreate))
                {
                    fs.Seek(part.Position, SeekOrigin.Begin);
                    var originalStream = fs;
                    if (downloadProgressCallback != null)
                    {
                        originalStream = _ossClient.SetupDownloadProgressListeners(fs,
                                                                        totalBytes,
                                                                        _downloadedBytes,
                                                                        _conf.ProgressUpdateInterval,
                                                                        downloadProgressCallback);
                    }

                    if (_conf.EnableCrcCheck)
                    {
                        originalStream = new Crc64Stream(originalStream, null, part.Length);
                    }

                    var getPartRequest = request.ToGetObjectRequest();
                    getPartRequest.SetRange(part.Position, part.Length + part.Position - 1);

                    var partResult = _ossClient.GetObject(getPartRequest);
                    WriteTo(partResult.Content, originalStream);

                    if (originalStream is Crc64Stream)
                    {
                        Crc64Stream crcStream = originalStream as Crc64Stream;

                        if (crcStream.CalculatedHash == null)
                        {
                            crcStream.CalculateHash();
                        }

                        part.Crc64 = BitConverter.ToUInt64(crcStream.CalculatedHash, 0);
                    }
                }

                part.IsCompleted = true;
                resumableContext.Dump();
                _downloadedBytes += part.Length;
            }

            Validate(request, resumableContext);
        }