private DataSet LoadData()

in src/Azure.IIoT.OpcUa.Publisher.Testing/src/HistoricalAccess/DataFileReader.cs [325:517]
148 lines of code
24 McCabe index (conditional complexity)

        private DataSet LoadData(ISystemContext context, DateTime baseline, StreamReader reader)
        {
            var dataset = CreateDataSet();

            var messageContext = new ServiceMessageContext();

            if (context != null)
            {
                messageContext.NamespaceUris = context.NamespaceUris;
                messageContext.ServerUris = context.ServerUris;
                messageContext.Factory = context.EncodeableFactory;
            }
            else
            {
                messageContext.NamespaceUris = ServiceMessageContext.GlobalContext.NamespaceUris;
                messageContext.ServerUris = ServiceMessageContext.GlobalContext.ServerUris;
                messageContext.Factory = ServiceMessageContext.GlobalContext.Factory;
            }

            var valueType = BuiltInType.String;
            var value = Variant.Null;
            var annotationTimeOffet = 0;
            var annotationUser = string.Empty;
            var annotationMessage = string.Empty;
            var lineCount = 0;

            while (!reader.EndOfStream)
            {
                var line = reader.ReadLine();

                // check for end or error.
                if (line == null)
                {
                    break;
                }

                // ignore blank lines.
                line = line.Trim();
                lineCount++;

                if (string.IsNullOrEmpty(line))
                {
                    continue;
                }

                // ignore commented out lines.
                if (line.StartsWith("//", StringComparison.CurrentCulture))
                {
                    continue;
                }

                // get source time.
                if (!ExtractField(lineCount, ref line, out int sourceTimeOffset))
                {
                    continue;
                }

                // get server time.
                if (!ExtractField(lineCount, ref line, out int serverTimeOffset))
                {
                    continue;
                }

                // get status code.
                if (!ExtractField(lineCount, ref line, out StatusCode status))
                {
                    continue;
                }

                // get modification type.
                if (!ExtractField(lineCount, ref line, out
                int recordType))
                {
                    continue;
                }

                // get modification time.
                if (!ExtractField(lineCount, ref line, out
                int modificationTimeOffet))
                {
                    continue;
                }

                // get modification user.
                if (!ExtractField(ref line, out var modificationUser))
                {
                    continue;
                }

                if (recordType >= 0)
                {
                    // get value type.
                    if (!ExtractField(lineCount, ref line, out valueType))
                    {
                        continue;
                    }

                    // get value.
                    if (!ExtractField(lineCount, ref line, messageContext, valueType, out value))
                    {
                        continue;
                    }
                }
                else
                {
                    // get annotation time.
                    if (!ExtractField(lineCount, ref line, out annotationTimeOffet))
                    {
                        continue;
                    }

                    // get annotation user.
                    if (!ExtractField(ref line, out annotationUser))
                    {
                        continue;
                    }

                    // get annotation message.
                    if (!ExtractField(ref line, out annotationMessage))
                    {
                        continue;
                    }
                }

                // add values to data table.
                var dataValue = new DataValue
                {
                    WrappedValue = value,
                    SourceTimestamp = baseline.AddMilliseconds(sourceTimeOffset),
                    ServerTimestamp = baseline.AddMilliseconds(serverTimeOffset),
                    StatusCode = status
                };

                DataRow row;
                if (recordType == 0)
                {
                    row = dataset.Tables[0].NewRow();

                    row[0] = dataValue.SourceTimestamp;
                    row[1] = dataValue.ServerTimestamp;
                    row[2] = dataValue;
                    row[3] = valueType;
                    row[4] = (value.TypeInfo != null) ? value.TypeInfo.ValueRank : ValueRanks.Any;

                    dataset.Tables[0].Rows.Add(row);
                }
                else if (recordType > 0)
                {
                    row = dataset.Tables[1].NewRow();

                    row[0] = dataValue.SourceTimestamp;
                    row[1] = dataValue.ServerTimestamp;
                    row[2] = dataValue;
                    row[3] = valueType;
                    row[4] = (value.TypeInfo != null) ? value.TypeInfo.ValueRank : ValueRanks.Any;
                    row[5] = recordType;

                    row[6] = new ModificationInfo
                    {
                        UpdateType = (HistoryUpdateType)recordType,
                        ModificationTime = baseline.AddMilliseconds(modificationTimeOffet),
                        UserName = modificationUser
                    };

                    dataset.Tables[1].Rows.Add(row);
                }
                else if (recordType < 0)
                {
                    row = dataset.Tables[2].NewRow();

                    var annotation = new Annotation
                    {
                        AnnotationTime = baseline.AddMilliseconds(annotationTimeOffet),
                        UserName = annotationUser,
                        Message = annotationMessage
                    };
                    dataValue.WrappedValue = new ExtensionObject(annotation);

                    row[0] = dataValue.SourceTimestamp;
                    row[1] = dataValue.ServerTimestamp;
                    row[2] = dataValue;
                    row[3] = valueType;
                    row[4] = (value.TypeInfo != null) ? value.TypeInfo.ValueRank : ValueRanks.Any;
                    row[5] = annotation;

                    dataset.Tables[2].Rows.Add(row);
                }

                dataset.AcceptChanges();
            }

            return dataset;
        }