BlobSync.AzureOps.GenerateByteRangesOfBlobToDownload C# (CSharp) Method

        private List<RemainingBytes> GenerateByteRangesOfBlobToDownload(List<BlockSignature> sigsToReuseList, SizeBasedCompleteSignature cloudBlobSig, string containerName, string blobName)
        {
            var blobSize = AzureHelper.GetBlobSize(containerName, blobName);
            var remainingBytesList = new List<RemainingBytes>();
            var allBlobSigs = cloudBlobSig.Signatures.Values.SelectMany(x => x.SignatureList).OrderBy(a => a.Offset).ToList();

            var sortedSigs = (from sig in sigsToReuseList orderby sig.Offset ascending select sig).ToList();

            long startOffsetToCopy = 0;

            // loop through all cloudBlobSigs.
            // If have a match in sigsToReuse, skip it.
            // otherwise, take note of offset and size to download.
            foreach( var sig in allBlobSigs)
            {
                var haveMatchingSig = sigsToReuseList.Any(s => s.MD5Signature.SequenceEqual(sig.MD5Signature));
                if (!haveMatchingSig)
                {
                    // if no match then we need to copy everything from startOffsetToCopy to sig.Offset + sig.Size
                    remainingBytesList.Add(new RemainingBytes()
                    {
                        BeginOffset = startOffsetToCopy,
                        EndOffset = sig.Offset + sig.Size -1
                    });
                    startOffsetToCopy = sig.Offset + sig.Size;
                }
                else
                {
                    // we have a match therefore dont need to copy the data.
                    // change startOffsetToCopy to just after current sig.
                    startOffsetToCopy = sig.Offset + sig.Size;
                }
            }

            return remainingBytesList;
        }