CmisSync.Lib.Consumer.SituationSolver.AbstractEnhancedSolver.DownloadChanges C# (CSharp) Method

        protected byte[] DownloadChanges(IFileInfo target, IDocument remoteDocument, IMappedObject obj, IFileSystemInfoFactory fsFactory, ITransmissionManager transmissionManager, ILog logger) {
            // Download changes
            byte[] hash = null;

            var cacheFile = fsFactory.CreateDownloadCacheFileInfo(target);
            var transmission = transmissionManager.CreateTransmission(TransmissionType.DOWNLOAD_MODIFIED_FILE, target.FullName, cacheFile.FullName);
            hash = this.DownloadCacheFile(cacheFile, remoteDocument, transmission, fsFactory);
            obj.ChecksumAlgorithmName = "SHA-1";

            try {
                var backupFile = fsFactory.CreateFileInfo(target.FullName + ".bak.sync");
                Guid? uuid = target.Uuid;
                cacheFile.Replace(target, backupFile, true);
                try {
                    target.Uuid = uuid;
                } catch (RestoreModificationDateException e) {
                    logger.Debug("Failed to restore modification date of original file", e);
                }

                try {
                    backupFile.Uuid = null;
                } catch (RestoreModificationDateException e) {
                    logger.Debug("Failed to restore modification date of backup file", e);
                }

                byte[] checksumOfOldFile = null;
                using (var oldFileStream = backupFile.Open(FileMode.Open, FileAccess.Read, FileShare.None)) {
                    checksumOfOldFile = SHA1Managed.Create().ComputeHash(oldFileStream);
                }

                if (!obj.LastChecksum.SequenceEqual(checksumOfOldFile)) {
                    var conflictFile = fsFactory.CreateConflictFileInfo(target);
                    backupFile.MoveTo(conflictFile.FullName);
                    OperationsLogger.Info(string.Format("Updated local content of \"{0}\" with content of remote document {1} and created conflict file {2}", target.FullName, remoteDocument.Id, conflictFile.FullName));
                } else {
                    backupFile.Delete();
                    OperationsLogger.Info(string.Format("Updated local content of \"{0}\" with content of remote document {1}", target.FullName, remoteDocument.Id));
                }
            } catch(Exception ex) {
                transmission.FailedException = ex;
                throw;
            }

            transmission.Status = TransmissionStatus.FINISHED;
            return hash;
        }