Opc.Ua.Server.AggregateCalculator.UpdateSlice C# (CSharp) Method

        protected bool UpdateSlice(TimeSlice slice)
        {
            // check if nothing to do.
            if (m_values.First == null)
            {
                return slice.Complete;
            }

            // restart processing from where it left off.
            LinkedListNode<DataValue> start = m_values.First;

            if (!TimeFlowsBackward && slice.LastProcessedValue != null)
            {
                start = slice.LastProcessedValue.Next; 
            }

            // reset the begin bound each time we go through the values.
            if (TimeFlowsBackward)
            {
                slice.Begin = null;
            }
            
            // initialize slice from value list.
            for (LinkedListNode<DataValue> ii = start; ii != null; ii = ii.Next)
            {
                if (TimeFlowsBackward)
                {
                    // check if before the beginning of the slice.
                    if (CompareTimestamps(slice.StartTime, ii) >= 0)
                    {
                        if (IsGood(ii.Value))
                        {
                            slice.SecondEarlyBound = slice.EarlyBound;
                            slice.EarlyBound = ii;
                        }

                        continue;
                    }

                    // check if after the end if the slice.
                    if (CompareTimestamps(slice.EndTime, ii) < 0)
                    {
                        if (IsGood(ii.Value))
                        {
                            slice.LateBound = ii;
                            break;
                        }

                        continue;
                    }

                    // save first value in the slice.
                    if (slice.End == null)
                    {
                        slice.End = ii;
                    }

                    // save end of slice.
                    if (slice.Begin == null)
                    {
                        slice.Begin = ii;
                        slice.LastProcessedValue = ii;
                    }
                }
                else
                {
                    // check if before the beginning of the slice.
                    if (CompareTimestamps(slice.StartTime, ii) > 0)
                    {
                        if (IsGood(ii.Value))
                        {
                            slice.SecondEarlyBound = slice.EarlyBound;
                            slice.EarlyBound = ii;
                            slice.LastProcessedValue = ii;
                        }

                        continue;
                    }

                    // check if after the end if the slice.
                    if (CompareTimestamps(slice.EndTime, ii) < 0)
                    {
                        if (IsGood(ii.Value))
                        {
                            slice.LateBound = ii;
                            slice.LastProcessedValue = ii;
                            break;
                        }

                        continue;
                    }

                    // save first value in the slice.
                    if (slice.Begin == null)
                    {
                        slice.Begin = ii;
                    }

                    // save end of slice.
                    slice.End = ii;
                    slice.LastProcessedValue = ii;
                }
            }

            // check if no more data needs to be collected.
            LinkedListNode<DataValue> requiredBound = null;

            if (TimeFlowsBackward)
            {
                // only need second early bound if using sloped extrapolation and there is no late bound.
                if (Configuration.UseSlopedExtrapolation && slice.LateBound == null)
                {
                    requiredBound = slice.SecondEarlyBound;
                }
                else
                {
                    requiredBound = slice.EarlyBound;
                }
            }
            else
            {
                requiredBound = slice.LateBound;
            }

            // all done if required bound exists.
            if (requiredBound != null)
            {
                slice.Complete = true;
            }

            return slice.Complete;
        }