private void EnsureIteration()

in code/KustoCopyConsole/Runner/MainRunner.cs [144:190]
43 lines of code
7 McCabe index (conditional complexity)

        private void EnsureIteration(ActivityParameterization activityParam)
        {
            if (activityParam.TableOption.ExportMode != ExportMode.BackfillOnly)
            {
                throw new NotSupportedException(
                    $"'{activityParam.TableOption.ExportMode}' isn't supported yet");
            }

            var cache = RowItemGateway.InMemoryCache;
            var cachedIterations = cache.ActivityMap.ContainsKey(activityParam.ActivityName)
                ? cache.ActivityMap[activityParam.ActivityName].IterationMap.Values
                : Array.Empty<IterationCache>();
            var completedIterations = cachedIterations
                .Select(c => c.RowItem)
                .Where(i => i.State == IterationState.Completed);
            var activeIterations = cachedIterations
                .Select(c => c.RowItem)
                .Where(i => i.State != IterationState.Completed);
            var isBackfillOnly =
                activityParam.TableOption.ExportMode == ExportMode.BackfillOnly;

            //  Start new iteration if need to
            if (!cachedIterations.Any())
            {
                var lastIteration = cachedIterations.Any()
                    ? cachedIterations.ArgMax(i => i.RowItem.IterationId).RowItem
                    : null;
                var newIterationId = lastIteration != null
                    ? lastIteration.IterationId + 1
                    : 1;
                var cursorStart = lastIteration != null
                    ? lastIteration.CursorEnd
                    : string.Empty;
                var newIterationItem = new IterationRowItem
                {
                    State = IterationState.Starting,
                    ActivityName = activityParam.ActivityName,
                    IterationId = newIterationId,
                    CursorStart = cursorStart,
                    CursorEnd = string.Empty
                };
                var iterationKey = newIterationItem.GetIterationKey();

                RowItemGateway.Append(newIterationItem);
                DisplayIteration(newIterationItem, true);
            }
        }