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/**
 * Copyright (c) 2016-2022 Deephaven Data Labs and Patent Pending
 */
package io.deephaven.engine.table.impl.by;

import gnu.trove.impl.Constants;
import gnu.trove.map.TObjectIntMap;
import gnu.trove.map.hash.TObjectIntHashMap;
import io.deephaven.api.ColumnName;
import io.deephaven.base.Pair;
import io.deephaven.base.verify.Assert;
import io.deephaven.base.verify.Require;
import io.deephaven.chunk.*;
import io.deephaven.chunk.attributes.ChunkLengths;
import io.deephaven.chunk.attributes.ChunkPositions;
import io.deephaven.chunk.attributes.Values;
import io.deephaven.configuration.Configuration;
import io.deephaven.engine.context.ExecutionContext;
import io.deephaven.engine.rowset.*;
import io.deephaven.engine.rowset.chunkattributes.OrderedRowKeys;
import io.deephaven.engine.rowset.chunkattributes.RowKeys;
import io.deephaven.engine.table.*;
import io.deephaven.engine.table.impl.*;
import io.deephaven.engine.table.impl.NoSuchColumnException.Type;
import io.deephaven.engine.table.impl.by.typed.TypedHasherFactory;
import io.deephaven.engine.table.impl.indexer.RowSetIndexer;
import io.deephaven.engine.table.impl.remote.ConstructSnapshot;
import io.deephaven.engine.table.impl.sort.findruns.IntFindRunsKernel;
import io.deephaven.engine.table.impl.sort.permute.LongPermuteKernel;
import io.deephaven.engine.table.impl.sort.permute.PermuteKernel;
import io.deephaven.engine.table.impl.sort.timsort.IntIntTimsortKernel;
import io.deephaven.engine.table.impl.sources.ArrayBackedColumnSource;
import io.deephaven.engine.table.impl.sources.ObjectArraySource;
import io.deephaven.engine.table.impl.sources.ReinterpretUtils;
import io.deephaven.engine.table.impl.sources.regioned.SymbolTableSource;
import io.deephaven.engine.table.impl.util.ChunkUtils;
import io.deephaven.engine.table.impl.util.UpdateSizeCalculator;
import io.deephaven.util.SafeCloseable;
import io.deephaven.util.SafeCloseableArray;
import io.deephaven.util.SafeCloseableList;
import io.deephaven.util.annotations.ReferentialIntegrity;
import io.deephaven.util.annotations.VisibleForTesting;
import org.apache.commons.lang3.mutable.Mutable;
import org.apache.commons.lang3.mutable.MutableInt;
import org.apache.commons.lang3.mutable.MutableObject;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.*;
import java.util.function.LongFunction;
import java.util.function.Supplier;
import java.util.function.UnaryOperator;

import static io.deephaven.engine.table.impl.by.AggregationRowLookup.DEFAULT_UNKNOWN_ROW;
import static io.deephaven.engine.table.impl.by.AggregationRowLookup.EMPTY_KEY;

@SuppressWarnings("rawtypes")
public class ChunkedOperatorAggregationHelper {

    static final int CHUNK_SIZE =
            Configuration.getInstance().getIntegerWithDefault("ChunkedOperatorAggregationHelper.chunkSize", 1 << 12);
    public static final boolean SKIP_RUN_FIND =
            Configuration.getInstance().getBooleanWithDefault("ChunkedOperatorAggregationHelper.skipRunFind", false);
    static final boolean HASHED_RUN_FIND =
            Configuration.getInstance().getBooleanWithDefault("ChunkedOperatorAggregationHelper.hashedRunFind", true);
    static boolean USE_OPEN_ADDRESSED_STATE_MANAGER =
            Configuration.getInstance().getBooleanWithDefault(
                    "ChunkedOperatorAggregationHelper.useOpenAddressedStateManager",
                    true);

    public static QueryTable aggregation(
            @NotNull final AggregationContextFactory aggregationContextFactory,
            @NotNull final QueryTable input,
            final boolean preserveEmpty,
            @Nullable final Table initialKeys,
            @NotNull final Collection groupByColumns) {
        return aggregation(AggregationControl.DEFAULT_FOR_OPERATOR,
                aggregationContextFactory, input, preserveEmpty, initialKeys, groupByColumns);
    }

    private static void checkGroupByColumns(String context, TableDefinition tableDefinition, String[] keyNames) {
        NoSuchColumnException.throwIf(
                tableDefinition.getColumnNameSet(),
                Arrays.asList(keyNames),
                String.format(
                        "aggregation: not all group-by columns [%%s] are present in %s with columns [%%s]. Missing columns: [%%s]",
                        context),
                Type.REQUESTED,
                Type.AVAILABLE,
                Type.MISSING);
    }

    @VisibleForTesting
    public static QueryTable aggregation(
            @NotNull final AggregationControl control,
            @NotNull final AggregationContextFactory aggregationContextFactory,
            @NotNull final QueryTable input,
            final boolean preserveEmpty,
            @Nullable final Table initialKeys,
            @NotNull final Collection groupByColumns) {
        final String[] keyNames = groupByColumns.stream().map(ColumnName::name).toArray(String[]::new);
        checkGroupByColumns("input table", input.getDefinition(), keyNames);
        if (initialKeys != null) {
            if (keyNames.length == 0) {
                throw new IllegalArgumentException(
                        "aggregation: initial groups must not be specified if no group-by columns are specified");
            }
            checkGroupByColumns("initial groups", initialKeys.getDefinition(), keyNames);
            for (final String keyName : keyNames) {
                final ColumnDefinition inputDef = input.getDefinition().getColumn(keyName);
                final ColumnDefinition initialKeysDef = initialKeys.getDefinition().getColumn(keyName);
                if (!inputDef.isCompatible(initialKeysDef)) {
                    throw new IllegalArgumentException(String.format(
                            "aggregation: column definition mismatch between input table and initial groups table for %s; input has %s, initial groups has %s",
                            keyName,
                            inputDef.describeForCompatibility(),
                            initialKeysDef.describeForCompatibility()));
                }
            }
        }
        final Mutable resultHolder = new MutableObject<>();
        final OperationSnapshotControl snapshotControl =
                input.createSnapshotControlIfRefreshing(OperationSnapshotControl::new);
        BaseTable.initializeWithSnapshot(
                "by(" + aggregationContextFactory + ", " + groupByColumns + ")", snapshotControl,
                (usePrev, beforeClockValue) -> {
                    resultHolder.setValue(aggregation(control, snapshotControl, aggregationContextFactory,
                            input, preserveEmpty, initialKeys, keyNames, usePrev));
                    return true;
                });
        return resultHolder.getValue();
    }

    private static QueryTable aggregation(
            @NotNull final AggregationControl control,
            @Nullable final OperationSnapshotControl snapshotControl,
            @NotNull final AggregationContextFactory aggregationContextFactory,
            @NotNull final QueryTable input,
            final boolean preserveEmpty,
            @Nullable final Table initialKeys,
            @NotNull final String[] keyNames,
            final boolean usePrev) {
        if (keyNames.length == 0) {
            // This should be checked before this method is called, but let's verify here in case an additional
            // entry point is added incautiously.
            Assert.eqNull(initialKeys, "initialKeys");
            return noKeyAggregation(snapshotControl, aggregationContextFactory, input, preserveEmpty, usePrev);
        }

        final ColumnSource[] keySources =
                Arrays.stream(keyNames).map(input::getColumnSource).toArray(ColumnSource[]::new);
        final ColumnSource[] reinterpretedKeySources = Arrays.stream(keySources)
                .map(ReinterpretUtils::maybeConvertToPrimitive).toArray(ColumnSource[]::new);

        final AggregationContext ac = aggregationContextFactory.makeAggregationContext(
                input, input.isRefreshing() && !preserveEmpty, keyNames);

        final PermuteKernel[] permuteKernels = ac.makePermuteKernels();

        final boolean useGrouping;
        if (control.considerGrouping(input, keySources)) {
            Assert.eq(keySources.length, "keySources.length", 1);

            final boolean hasGrouping = RowSetIndexer.of(input.getRowSet()).hasGrouping(keySources[0]);
            if (!input.isRefreshing() && hasGrouping && initialKeys == null) {
                return staticGroupedAggregation(input, keyNames[0], keySources[0], ac);
            }
            // we have no hasPrevGrouping method
            useGrouping = !usePrev && hasGrouping && Arrays.equals(reinterpretedKeySources, keySources);
        } else {
            useGrouping = false;
        }

        final Table symbolTable;
        final boolean useSymbolTable;
        if (!input.isRefreshing() && control.considerSymbolTables(input, useGrouping, keySources)) {
            Assert.eq(keySources.length, "keySources.length", 1);

            symbolTable = ((SymbolTableSource) keySources[0]).getStaticSymbolTable(input.getRowSet(),
                    control.useSymbolTableLookupCaching());
            useSymbolTable = control.useSymbolTables(input.size(), symbolTable.size());
        } else {
            symbolTable = null;
            useSymbolTable = false;
        }

        final MutableInt outputPosition = new MutableInt();
        final Supplier stateManagerSupplier =
                () -> makeStateManager(control, input, keySources, reinterpretedKeySources, ac,
                        useSymbolTable ? symbolTable : null);
        final OperatorAggregationStateManager stateManager;
        if (initialKeys == null) {
            stateManager = stateManagerSupplier.get();
        } else {
            stateManager = initialKeyTableAddition(control, initialKeys, keyNames, ac, outputPosition,
                    stateManagerSupplier);
        }

        final RowSetBuilderRandom initialRowsBuilder =
                initialKeys != null && !preserveEmpty ? new BitmapRandomBuilder(stateManager.maxTableSize() - 1) : null;
        if (useGrouping) {
            initialGroupedKeyAddition(input, reinterpretedKeySources, ac, stateManager, outputPosition,
                    initialRowsBuilder, usePrev);
        } else {
            initialBucketedKeyAddition(input, reinterpretedKeySources, ac, permuteKernels, stateManager,
                    outputPosition, initialRowsBuilder, usePrev);
        }

        // Construct and return result table
        final ColumnSource[] keyHashTableSources = stateManager.getKeyHashTableSources();
        final Map> resultColumnSourceMap = new LinkedHashMap<>();

        // Gather the result key columns
        final ColumnSource[] keyColumnsRaw = new ColumnSource[keyHashTableSources.length];
        final WritableColumnSource[] keyColumnsCopied =
                input.isRefreshing() ? new WritableColumnSource[keyHashTableSources.length] : null;
        for (int kci = 0; kci < keyHashTableSources.length; ++kci) {
            ColumnSource resultKeyColumnSource = keyHashTableSources[kci];
            if (keySources[kci] != reinterpretedKeySources[kci]) {
                resultKeyColumnSource = ReinterpretUtils.convertToOriginalType(keySources[kci], resultKeyColumnSource);
            }
            keyColumnsRaw[kci] = resultKeyColumnSource;
            if (input.isRefreshing()) {
                // noinspection ConstantConditions,unchecked
                keyColumnsCopied[kci] = ArrayBackedColumnSource.getMemoryColumnSource(outputPosition.intValue(),
                        keyColumnsRaw[kci].getType());
                resultColumnSourceMap.put(keyNames[kci], keyColumnsCopied[kci]);
            } else {
                resultColumnSourceMap.put(keyNames[kci], keyColumnsRaw[kci]);
            }
        }
        ac.getResultColumns(resultColumnSourceMap);

        final TrackingWritableRowSet resultRowSet = (initialRowsBuilder == null
                ? RowSetFactory.flat(outputPosition.intValue())
                : initialRowsBuilder.build()).toTracking();
        if (input.isRefreshing()) {
            copyKeyColumns(keyColumnsRaw, keyColumnsCopied, resultRowSet);
        }

        // Construct the result table
        final QueryTable result = new QueryTable(resultRowSet, resultColumnSourceMap);
        ac.propagateInitialStateToOperators(result, outputPosition.intValue());

        if (input.isRefreshing()) {
            assert keyColumnsCopied != null;

            ac.startTrackingPrevValues();
            final IncrementalOperatorAggregationStateManager incrementalStateManager =
                    (IncrementalOperatorAggregationStateManager) stateManager;
            incrementalStateManager.startTrackingPrevValues();

            final boolean isBlink = input.isBlink();
            final TableUpdateListener listener =
                    new BaseTable.ListenerImpl("by(" + aggregationContextFactory + ")", input, result) {
                        @ReferentialIntegrity
                        final OperationSnapshotControl swapListenerHardReference = snapshotControl;

                        final ModifiedColumnSet keysUpstreamModifiedColumnSet = input.newModifiedColumnSet(keyNames);
                        final ModifiedColumnSet[] operatorInputModifiedColumnSets =
                                ac.getInputModifiedColumnSets(input);
                        final UnaryOperator[] resultModifiedColumnSetFactories =
                                ac.initializeRefreshing(result, this);

                        final StateChangeRecorder stateChangeRecorder =
                                preserveEmpty ? null : ac.getStateChangeRecorder();

                        @Override
                        public void onUpdate(@NotNull final TableUpdate upstream) {
                            incrementalStateManager.beginUpdateCycle();

                            final TableUpdate upstreamToUse = isBlink ? adjustForBlinkTable(upstream) : upstream;
                            if (upstreamToUse.empty()) {
                                return;
                            }
                            final TableUpdate downstream;
                            try (final KeyedUpdateContext kuc = new KeyedUpdateContext(ac, incrementalStateManager,
                                    reinterpretedKeySources, permuteKernels, keysUpstreamModifiedColumnSet,
                                    operatorInputModifiedColumnSets, stateChangeRecorder, upstreamToUse,
                                    outputPosition)) {
                                downstream = kuc.computeDownstreamIndicesAndCopyKeys(input.getRowSet(),
                                        keyColumnsRaw,
                                        keyColumnsCopied,
                                        result.getModifiedColumnSetForUpdates(), resultModifiedColumnSetFactories);
                            }

                            if (downstream.empty()) {
                                downstream.release();
                                return;
                            }

                            result.getRowSet().writableCast().update(downstream.added(), downstream.removed());
                            result.notifyListeners(downstream);
                        }

                        @Override
                        public void onFailureInternal(@NotNull final Throwable originalException, Entry sourceEntry) {
                            ac.propagateFailureToOperators(originalException, sourceEntry);
                            super.onFailureInternal(originalException, sourceEntry);
                        }
                    };

            snapshotControl.setListenerAndResult(listener, result);
        }

        final QueryTable finalResult = ac.transformResult(result);
        final boolean noInitialKeys = initialKeys == null || (!initialKeys.isRefreshing() && initialKeys.isEmpty());
        if (!input.isRefreshing() && finalResult.getRowSet().isFlat()) {
            finalResult.setFlat();
        } else if ((input.isAddOnly() || input.isAppendOnly() || input.isBlink()) && (noInitialKeys || preserveEmpty)) {
            finalResult.setFlat();
        }
        return finalResult;
    }

    private static OperatorAggregationStateManager makeStateManager(
            @NotNull final AggregationControl control, @NotNull final QueryTable input,
            @NotNull final ColumnSource[] keySources, @NotNull final ColumnSource[] reinterpretedKeySources,
            @NotNull final AggregationContext ac,
            @Nullable final Table symbolTableToUse) {
        final OperatorAggregationStateManager stateManager;
        if (input.isRefreshing()) {
            if (USE_OPEN_ADDRESSED_STATE_MANAGER) {
                stateManager = TypedHasherFactory.make(
                        IncrementalChunkedOperatorAggregationStateManagerOpenAddressedBase.class,
                        reinterpretedKeySources,
                        keySources, control.initialHashTableSize(input), control.getMaximumLoadFactor(),
                        control.getTargetLoadFactor());
            } else {
                stateManager = TypedHasherFactory.make(
                        IncrementalChunkedOperatorAggregationStateManagerTypedBase.class, reinterpretedKeySources,
                        keySources, control.initialHashTableSize(input), control.getMaximumLoadFactor(),
                        control.getTargetLoadFactor());
            }
        } else {
            if (symbolTableToUse != null) {
                stateManager = new StaticSymbolTableChunkedOperatorAggregationStateManager(reinterpretedKeySources[0],
                        symbolTableToUse);
            } else if (USE_OPEN_ADDRESSED_STATE_MANAGER) {
                stateManager = TypedHasherFactory.make(
                        StaticChunkedOperatorAggregationStateManagerOpenAddressedBase.class,
                        reinterpretedKeySources,
                        keySources, control.initialHashTableSize(input), control.getMaximumLoadFactor(),
                        control.getTargetLoadFactor());
            } else {
                stateManager = TypedHasherFactory.make(
                        StaticChunkedOperatorAggregationStateManagerTypedBase.class, reinterpretedKeySources,
                        keySources, control.initialHashTableSize(input), control.getMaximumLoadFactor(),
                        control.getTargetLoadFactor());
            }
        }
        ac.supplyRowLookup(() -> stateManager::findPositionForKey);
        return stateManager;
    }

    private static TableUpdate adjustForBlinkTable(@NotNull final TableUpdate upstream) {
        // Blink table aggregations never have modifies or shifts from their parent:
        Assert.assertion(upstream.modified().isEmpty() && upstream.shifted().empty(),
                "upstream.modified.empty() && upstream.shifted.empty()");
        // Blink table aggregations ignore removes:
        if (upstream.removed().isEmpty()) {
            return upstream;
        }
        return new TableUpdateImpl(upstream.added(), RowSetFactory.empty(), upstream.modified(), upstream.shifted(),
                upstream.modifiedColumnSet());
    }

    private static class KeyedUpdateContext implements SafeCloseable {

        private final AggregationContext ac;
        private final IncrementalOperatorAggregationStateManager incrementalStateManager;
        private final ColumnSource[] reinterpretedKeySources;
        private final PermuteKernel[] permuteKernels;
        private final StateChangeRecorder stateChangeRecorder;
        private final TableUpdate upstream; // Not to be mutated
        private final MutableInt outputPosition;

        private final ModifiedColumnSet updateUpstreamModifiedColumnSet; // Not to be mutated
        private final boolean keysModified;
        private final boolean shifted;
        private final boolean processShifts;
        private final OperatorDivision od;

        private final RowSetBuilderRandom reincarnatedStatesBuilder;
        private final RowSetBuilderRandom emptiedStatesBuilder;
        private final RowSetBuilderRandom modifiedStatesBuilder;
        private final boolean[] modifiedOperators;

        private final SafeCloseableList toClose;

        private final IterativeChunkedAggregationOperator.BucketedContext[] bucketedContexts;
        private final IntIntTimsortKernel.IntIntSortKernelContext sortKernelContext;
        private final HashedRunFinder.HashedRunContext hashedRunContext;

        // These are used for all access when only pre- or post-shift (or previous or current) are needed, else for
        // pre-shift/previous
        private final SharedContext sharedContext;
        private final ChunkSource.GetContext[] getContexts;
        private final WritableChunk[] workingChunks;
        private final WritableLongChunk permutedKeyIndices;

        // These are used when post-shift/current values are needed concurrently with pre-shift/previous
        private final SharedContext postSharedContext;
        private final ChunkSource.GetContext[] postGetContexts;
        private final WritableChunk[] postWorkingChunks;
        private final WritableLongChunk postPermutedKeyIndices;

        // the valueChunks and postValueChunks arrays never own a chunk, they havea reference to workingChunks or a
        // chunk returned from a get context, and thus are not closed by this context
        private final Chunk[] valueChunks;
        private final Chunk[] postValueChunks;

        private final WritableIntChunk runStarts;
        private final WritableIntChunk runLengths;
        private final WritableIntChunk chunkPositions;
        private final WritableIntChunk slots;
        private final WritableBooleanChunk modifiedSlots;
        private final WritableBooleanChunk slotsModifiedByOperator;

        private final SafeCloseable bc;
        private final int buildChunkSize;

        private final SafeCloseable pc;
        private final int probeChunkSize;

        private KeyedUpdateContext(@NotNull final AggregationContext ac,
                @NotNull final IncrementalOperatorAggregationStateManager incrementalStateManager,
                @NotNull final ColumnSource[] reinterpretedKeySources,
                @NotNull final PermuteKernel[] permuteKernels,
                @NotNull final ModifiedColumnSet keysUpstreamModifiedColumnSet,
                @NotNull final ModifiedColumnSet[] operatorInputUpstreamModifiedColumnSets,
                @Nullable final StateChangeRecorder stateChangeRecorder,
                @NotNull final TableUpdate upstream,
                @NotNull final MutableInt outputPosition) {
            this.ac = ac;
            this.incrementalStateManager = incrementalStateManager;
            this.reinterpretedKeySources = reinterpretedKeySources;
            this.permuteKernels = permuteKernels;
            this.stateChangeRecorder = stateChangeRecorder;
            this.upstream = upstream;
            this.outputPosition = outputPosition;

            updateUpstreamModifiedColumnSet =
                    upstream.modified().isEmpty() ? ModifiedColumnSet.EMPTY : upstream.modifiedColumnSet();
            keysModified = updateUpstreamModifiedColumnSet.containsAny(keysUpstreamModifiedColumnSet);
            shifted = upstream.shifted().nonempty();
            processShifts = ac.requiresIndices() && shifted;
            od = new OperatorDivision(ac, upstream.modified().isNonempty(), updateUpstreamModifiedColumnSet,
                    operatorInputUpstreamModifiedColumnSets);

            final long buildSize = Math.max(upstream.added().size(), keysModified ? upstream.modified().size() : 0);
            final long probeSizeForModifies =
                    (keysModified || od.anyOperatorHasModifiedInputColumns || ac.requiresIndices())
                            ? upstream.modified().size()
                            : 0;
            final long probeSizeWithoutShifts = Math.max(upstream.removed().size(), probeSizeForModifies);
            final long probeSize =
                    processShifts
                            ? UpdateSizeCalculator.chunkSize(probeSizeWithoutShifts, upstream.shifted(), CHUNK_SIZE)
                            : probeSizeWithoutShifts;
            buildChunkSize = chunkSize(buildSize);
            probeChunkSize = chunkSize(probeSize);
            final int chunkSize = Math.max(buildChunkSize, probeChunkSize);

            if (stateChangeRecorder != null) {
                reincarnatedStatesBuilder = RowSetFactory.builderRandom();
                emptiedStatesBuilder = RowSetFactory.builderRandom();
                stateChangeRecorder.startRecording(reincarnatedStatesBuilder::addKey, emptiedStatesBuilder::addKey);
            } else {
                reincarnatedStatesBuilder = new EmptyRandomBuilder();
                emptiedStatesBuilder = new EmptyRandomBuilder();
            }
            modifiedStatesBuilder = new BitmapRandomBuilder(outputPosition.intValue());
            modifiedOperators = new boolean[ac.size()];

            toClose = new SafeCloseableList();

            bucketedContexts = toClose.addArray(new IterativeChunkedAggregationOperator.BucketedContext[ac.size()]);
            ac.initializeBucketedContexts(bucketedContexts, upstream, keysModified,
                    od.operatorsWithModifiedInputColumns);
            final boolean findRuns = ac.requiresRunFinds(SKIP_RUN_FIND);
            sortKernelContext =
                    !findRuns || HASHED_RUN_FIND ? null : toClose.add(IntIntTimsortKernel.createContext(chunkSize));
            // even if we are not finding runs because of configuration or operators, we may have a shift in which case
            // we still need to find runs
            hashedRunContext =
                    !HASHED_RUN_FIND ? null : toClose.add(new HashedRunFinder.HashedRunContext(chunkSize));

            sharedContext = toClose.add(SharedContext.makeSharedContext());
            getContexts = toClose.addArray(new ChunkSource.GetContext[ac.size()]);
            ac.initializeGetContexts(sharedContext, getContexts, chunkSize);
            // noinspection unchecked
            workingChunks = toClose.addArray(new WritableChunk[ac.size()]);
            valueChunks = new Chunk[ac.size()];
            postValueChunks = new Chunk[ac.size()];
            ac.initializeWorkingChunks(workingChunks, chunkSize);
            permutedKeyIndices =
                    ac.requiresIndices() || keysModified ? toClose.add(WritableLongChunk.makeWritableChunk(chunkSize))
                            : null;

            postPermutedKeyIndices = processShifts || keysModified // Note that we need this for modified keys because
                                                                   // we use it to hold removed key indices
                    ? toClose.add(WritableLongChunk.makeWritableChunk(chunkSize))
                    : null;

            if (od.anyOperatorHasModifiedInputColumns || processShifts) {
                postSharedContext = toClose.add(SharedContext.makeSharedContext());
                postGetContexts = toClose.addArray(new ChunkSource.GetContext[ac.size()]);
                ac.initializeGetContexts(postSharedContext, postGetContexts, probeChunkSize);
                // noinspection unchecked
                postWorkingChunks = toClose.addArray(new WritableChunk[ac.size()]);
                ac.initializeWorkingChunks(postWorkingChunks, probeChunkSize);
            } else {
                postSharedContext = null;
                postGetContexts = null;
                postWorkingChunks = null;
            }

            runStarts = toClose.add(WritableIntChunk.makeWritableChunk(chunkSize));
            runLengths = toClose.add(WritableIntChunk.makeWritableChunk(chunkSize));
            chunkPositions = toClose.add(WritableIntChunk.makeWritableChunk(chunkSize));
            slots = toClose.add(WritableIntChunk.makeWritableChunk(chunkSize));
            modifiedSlots = toClose.add(WritableBooleanChunk.makeWritableChunk(chunkSize));
            slotsModifiedByOperator = toClose.add(WritableBooleanChunk.makeWritableChunk(chunkSize));

            if (buildSize > 0) {
                bc = toClose.add(
                        incrementalStateManager.makeAggregationStateBuildContext(reinterpretedKeySources, buildSize));
            } else {
                bc = null;
            }
            if (probeSize > 0) {
                pc = toClose.add(incrementalStateManager.makeProbeContext(reinterpretedKeySources, probeSize));
            } else {
                pc = null;
            }
        }

        @Override
        public final void close() {
            toClose.close();
        }

        private TableUpdate computeDownstreamIndicesAndCopyKeys(
                @NotNull final RowSet upstreamIndex,
                @NotNull final ColumnSource[] keyColumnsRaw,
                @NotNull final WritableColumnSource[] keyColumnsCopied,
                @NotNull final ModifiedColumnSet resultModifiedColumnSet,
                @NotNull final UnaryOperator[] resultModifiedColumnSetFactories) {
            final int firstStateToAdd = outputPosition.intValue();
            ac.resetOperatorsForStep(upstream, firstStateToAdd);

            if (upstream.removed().isNonempty()) {
                doRemoves(upstream.removed());
            }
            if (upstream.modified().isNonempty() && (od.anyOperatorHasModifiedInputColumns
                    || od.anyOperatorWithoutModifiedInputColumnsRequiresIndices || keysModified)) {
                try (final ModifySplitResult split =
                        keysModified ? splitKeyModificationsAndDoKeyChangeRemoves() : null) {
                    if (processShifts) {
                        try (final WritableRowSet postShiftRowSet = upstreamIndex.minus(upstream.added())) {
                            if (keysModified) {
                                postShiftRowSet.remove(split.keyChangeIndicesPostShift);
                            }
                            doShifts(postShiftRowSet); // Also handles shifted same-key modifications for modified-input
                                                       // operators that require indices (if any)
                        }
                        try (final RowSet keysSameUnshiftedModifies =
                                keysModified ? null : getUnshiftedModifies()) {
                            // Do unshifted modifies for everyone
                            assert !keysModified || split.unshiftedSameSlotIndices != null;
                            final RowSet unshiftedSameSlotModifies =
                                    keysModified ? split.unshiftedSameSlotIndices : keysSameUnshiftedModifies;
                            doSameSlotModifies(unshiftedSameSlotModifies, unshiftedSameSlotModifies, true /*
                                                                                                           * We don't
                                                                                                           * process
                                                                                                           * shifts
                                                                                                           * unless some
                                                                                                           * operator
                                                                                                           * requires
                                                                                                           * indices
                                                                                                           */,
                                    od.operatorsWithModifiedInputColumns,
                                    od.operatorsWithoutModifiedInputColumnsThatRequireIndices);

                            if (od.anyOperatorWithModifiedInputColumnsIgnoresIndices) {
                                // Do shifted same-key modifies for RowSet-only and modified-input operators that don't
                                // require indices
                                try (final RowSet removeIndex =
                                        keysModified ? unshiftedSameSlotModifies.union(split.keyChangeIndicesPostShift)
                                                : null;
                                        final RowSet shiftedSameSlotModifiesPost = upstream.modified()
                                                .minus(removeIndex == null ? unshiftedSameSlotModifies : removeIndex);
                                        final WritableRowSet shiftedSameSlotModifiesPre =
                                                shiftedSameSlotModifiesPost.copy()) {
                                    upstream.shifted().unapply(shiftedSameSlotModifiesPre);
                                    doSameSlotModifies(shiftedSameSlotModifiesPre, shiftedSameSlotModifiesPost, true,
                                            od.operatorsWithModifiedInputColumnsThatIgnoreIndices,
                                            od.operatorsThatRequireIndices);
                                }
                            } else if (ac.requiresIndices()) {
                                // Do shifted same-key modifies for RowSet-only operators
                                try (final WritableRowSet shiftedSameSlotModifiesPost =
                                        upstream.modified().minus(unshiftedSameSlotModifies)) {
                                    if (keysModified) {
                                        shiftedSameSlotModifiesPost.remove(split.keyChangeIndicesPostShift);
                                    }
                                    doSameSlotModifyIndicesOnly(shiftedSameSlotModifiesPost,
                                            od.operatorsThatRequireIndices);
                                }
                            }
                        }
                    } else if (od.anyOperatorHasModifiedInputColumns) {
                        assert !keysModified || split.sameSlotIndicesPreShift != null;
                        assert !keysModified || split.sameSlotIndicesPostShift != null;
                        doSameSlotModifies(
                                keysModified ? split.sameSlotIndicesPreShift : upstream.getModifiedPreShift(),
                                keysModified ? split.sameSlotIndicesPostShift : upstream.modified(),
                                ac.requiresIndices(),
                                od.operatorsWithModifiedInputColumns,
                                od.operatorsWithoutModifiedInputColumnsThatRequireIndices);

                    } else {
                        assert !keysModified || split.sameSlotIndicesPostShift != null;
                        doSameSlotModifyIndicesOnly(
                                keysModified ? split.sameSlotIndicesPostShift : upstream.modified(),
                                od.operatorsWithoutModifiedInputColumnsThatRequireIndices);
                    }
                    if (keysModified) {
                        doInserts(split.keyChangeIndicesPostShift, false);
                    }
                }
            } else if (processShifts) {
                try (final RowSet postShiftRowSet = upstreamIndex.minus(upstream.added())) {
                    doShifts(postShiftRowSet);
                }
            }
            if (upstream.added().isNonempty()) {
                doInserts(upstream.added(), true);
            }

            if (stateChangeRecorder != null) {
                stateChangeRecorder.finishRecording();
            }
            final TableUpdateImpl downstream = new TableUpdateImpl();
            downstream.shifted = RowSetShiftData.EMPTY;

            try (final RowSet newStates = makeNewStatesRowSet(firstStateToAdd, outputPosition.intValue() - 1)) {
                downstream.added = reincarnatedStatesBuilder.build();
                downstream.removed = emptiedStatesBuilder.build();

                try (final RowSet addedBack = downstream.added().intersect(downstream.removed())) {
                    downstream.added().writableCast().remove(addedBack);
                    downstream.removed().writableCast().remove(addedBack);

                    if (newStates.isNonempty()) {
                        downstream.added().writableCast().insert(newStates);
                        copyKeyColumns(keyColumnsRaw, keyColumnsCopied, newStates);
                    }

                    downstream.modified = modifiedStatesBuilder.build();
                    downstream.modified().writableCast().remove(downstream.added());
                    downstream.modified().writableCast().remove(downstream.removed());
                }

                ac.propagateChangesToOperators(downstream, newStates);
            }

            extractDownstreamModifiedColumnSet(downstream, resultModifiedColumnSet, modifiedOperators,
                    updateUpstreamModifiedColumnSet, resultModifiedColumnSetFactories);

            return downstream;
        }

        private void doRemoves(@NotNull final RowSequence keyIndicesToRemove) {
            if (keyIndicesToRemove.isEmpty()) {
                return;
            }
            try (final RowSequence.Iterator keyIndicesToRemoveIterator = keyIndicesToRemove.getRowSequenceIterator()) {
                while (keyIndicesToRemoveIterator.hasMore()) {
                    doRemovesForChunk(keyIndicesToRemoveIterator.getNextRowSequenceWithLength(CHUNK_SIZE));
                }
            }
        }

        private void doRemovesForChunk(@NotNull final RowSequence keyIndicesToRemoveChunk) {
            incrementalStateManager.remove(pc, keyIndicesToRemoveChunk, reinterpretedKeySources, slots);
            propagateRemovesToOperators(keyIndicesToRemoveChunk, slots);
        }

        private void propagateRemovesToOperators(@NotNull final RowSequence keyIndicesToRemoveChunk,
                @NotNull final WritableIntChunk slotsToRemoveFrom) {
            final boolean permute = findSlotRuns(sortKernelContext, hashedRunContext, runStarts, runLengths,
                    chunkPositions, slotsToRemoveFrom,
                    ac.requiresRunFinds(SKIP_RUN_FIND));

            if (ac.requiresIndices()) {
                if (permute) {
                    final LongChunk keyIndices = keyIndicesToRemoveChunk.asRowKeyChunk();
                    permutedKeyIndices.setSize(keyIndices.size());
                    LongPermuteKernel.permuteInput(keyIndices, chunkPositions, permutedKeyIndices);
                } else {
                    keyIndicesToRemoveChunk.fillRowKeyChunk(permutedKeyIndices);
                }
            }

            boolean anyOperatorModified = false;
            boolean firstOperator = true;
            setFalse(modifiedSlots, runStarts.size());

            sharedContext.reset();
            for (int oi = 0; oi < ac.size(); ++oi) {
                if (!firstOperator) {
                    setFalse(slotsModifiedByOperator, runStarts.size());
                }

                final int inputSlot = ac.inputSlot(oi);
                if (oi == inputSlot) {
                    if (permute) {
                        valueChunks[oi] =
                                getAndPermuteChunk(ac.inputColumns[oi], getContexts[oi], keyIndicesToRemoveChunk, true,
                                        permuteKernels[oi], chunkPositions, workingChunks[oi]);
                    } else {
                        valueChunks[oi] =
                                getChunk(ac.inputColumns[oi], getContexts[oi], keyIndicesToRemoveChunk, true);
                    }
                }
                try {
                    ac.operators[oi].removeChunk(bucketedContexts[oi], inputSlot >= 0 ? valueChunks[inputSlot] : null,
                            permutedKeyIndices, slotsToRemoveFrom, runStarts, runLengths,
                            firstOperator ? modifiedSlots : slotsModifiedByOperator);
                } catch (Exception ex) {
                    throw new AggregationOperatorException(
                            "Failed to remove data, inputcolumns=" + Arrays.toString(ac.inputNames[oi]) + ", outputs="
                                    + ac.operators[oi].getResultColumns().keySet(),
                            ex);
                } catch (Error err) {
                    err.addSuppressed(new AggregationOperatorException(
                            "Failed to remove data, inputcolumns=" + Arrays.toString(ac.inputNames[oi]) + ", outputs="
                                    + ac.operators[oi].getResultColumns().keySet()));
                    throw err;
                }

                anyOperatorModified = updateModificationState(modifiedOperators, modifiedSlots, slotsModifiedByOperator,
                        anyOperatorModified, firstOperator, oi);
                firstOperator = false;
            }

            if (anyOperatorModified) {
                modifySlots(modifiedStatesBuilder, runStarts, slotsToRemoveFrom, modifiedSlots);
            }
        }

        private void doInserts(@NotNull final RowSequence keyIndicesToInsert, final boolean addToStateManager) {
            if (keyIndicesToInsert.isEmpty()) {
                return;
            }
            try (final RowSequence.Iterator keyIndicesToInsertIterator = keyIndicesToInsert.getRowSequenceIterator()) {
                while (keyIndicesToInsertIterator.hasMore()) {
                    doInsertsForChunk(keyIndicesToInsertIterator.getNextRowSequenceWithLength(CHUNK_SIZE),
                            addToStateManager);
                }
            }
        }

        private void doInsertsForChunk(@NotNull final RowSequence keyIndicesToInsertChunk,
                final boolean addToStateManager) {
            if (addToStateManager) {
                incrementalStateManager.add(bc, keyIndicesToInsertChunk, reinterpretedKeySources, outputPosition,
                        slots);
            } else {
                incrementalStateManager.findModifications(pc, keyIndicesToInsertChunk, reinterpretedKeySources, slots);
            }
            propagateInsertsToOperators(keyIndicesToInsertChunk, slots);
        }

        private void propagateInsertsToOperators(@NotNull final RowSequence keyIndicesToInsertChunk,
                @NotNull final WritableIntChunk slotsToAddTo) {
            ac.ensureCapacity(outputPosition.intValue());

            final boolean permute = findSlotRuns(sortKernelContext, hashedRunContext, runStarts, runLengths,
                    chunkPositions, slotsToAddTo,
                    ac.requiresRunFinds(SKIP_RUN_FIND));

            if (ac.requiresIndices()) {
                if (permute) {
                    final LongChunk keyIndices = keyIndicesToInsertChunk.asRowKeyChunk();
                    permutedKeyIndices.setSize(keyIndices.size());
                    LongPermuteKernel.permuteInput(keyIndices, chunkPositions, permutedKeyIndices);
                } else {
                    keyIndicesToInsertChunk.fillRowKeyChunk(permutedKeyIndices);
                }
            }

            boolean anyOperatorModified = false;
            boolean firstOperator = true;
            setFalse(modifiedSlots, runStarts.size());

            sharedContext.reset();
            for (int oi = 0; oi < ac.size(); ++oi) {
                if (!firstOperator) {
                    setFalse(slotsModifiedByOperator, runStarts.size());
                }

                final int inputSlot = ac.inputSlot(oi);
                if (inputSlot == oi) {
                    if (permute) {
                        valueChunks[oi] =
                                getAndPermuteChunk(ac.inputColumns[oi], getContexts[oi], keyIndicesToInsertChunk, false,
                                        permuteKernels[oi], chunkPositions, workingChunks[oi]);
                    } else {
                        valueChunks[oi] =
                                getChunk(ac.inputColumns[oi], getContexts[oi], keyIndicesToInsertChunk, false);
                    }
                }
                try {
                    ac.operators[oi].addChunk(bucketedContexts[oi], inputSlot >= 0 ? valueChunks[inputSlot] : null,
                            permutedKeyIndices, slotsToAddTo, runStarts, runLengths,
                            firstOperator ? modifiedSlots : slotsModifiedByOperator);
                } catch (Exception ex) {
                    throw new AggregationOperatorException(
                            "Failed to add data, inputcolumns=" + Arrays.toString(ac.inputNames[oi]) + ", outputs="
                                    + ac.operators[oi].getResultColumns().keySet(),
                            ex);
                } catch (Error err) {
                    err.addSuppressed(new AggregationOperatorException(
                            "Failed to add data, inputcolumns=" + Arrays.toString(ac.inputNames[oi]) + ", outputs="
                                    + ac.operators[oi].getResultColumns().keySet()));
                    throw err;
                }

                anyOperatorModified = updateModificationState(modifiedOperators, modifiedSlots, slotsModifiedByOperator,
                        anyOperatorModified, firstOperator, oi);
                firstOperator = false;
            }

            if (anyOperatorModified) {
                modifySlots(modifiedStatesBuilder, runStarts, slotsToAddTo, modifiedSlots);
            }
        }

        private void doShifts(@NotNull final RowSet postShiftIndexToProcess) {
            if (postShiftIndexToProcess.isEmpty()) {
                return;
            }
            try (final WritableLongChunk preKeyIndices =
                    WritableLongChunk.makeWritableChunk(probeChunkSize);
                    final WritableLongChunk postKeyIndices =
                            WritableLongChunk.makeWritableChunk(probeChunkSize)) {
                final Runnable applyChunkedShift = () -> doProcessShiftBucketed(preKeyIndices, postKeyIndices);
                processUpstreamShifts(upstream, postShiftIndexToProcess, preKeyIndices, postKeyIndices,
                        applyChunkedShift);
            }
        }

        private void doProcessShiftBucketed(@NotNull final WritableLongChunk preKeyIndices,
                @NotNull final WritableLongChunk postKeyIndices) {

            final boolean[] chunkInitialized = new boolean[ac.size()];

            final LongChunk usePreKeys;
            final LongChunk usePostKeys;

            try (final RowSequence preShiftChunkKeys =
                    RowSequenceFactory.wrapRowKeysChunkAsRowSequence(WritableLongChunk.downcast(preKeyIndices));
                    final RowSequence postShiftChunkKeys =
                            RowSequenceFactory
                                    .wrapRowKeysChunkAsRowSequence(WritableLongChunk.downcast(postKeyIndices))) {
                sharedContext.reset();
                postSharedContext.reset();
                Arrays.fill(chunkInitialized, false);

                incrementalStateManager.findModifications(pc, postShiftChunkKeys, reinterpretedKeySources, slots);
                // We must accumulate shifts into runs for the same slot, if we bounce from slot 1 to 2 and back to 1,
                // then the polarity checking logic can have us overwrite things because we wouldn't remove all the
                // values from a slot at the same time. Suppose you had
                // Slot RowKey
                // 1 1
                // 2 2
                // 1 3
                // And a shift of {1-3} + 2. We do not want to allow the 1 to shift over the three by removing 1, adding
                // 3; then the 3 would shift to 5 by removing 3 and adding 5. When runs are found you would have the
                // 1,3 removed and then 3,5 inserted without conflict.
                final boolean permute = findSlotRuns(sortKernelContext, hashedRunContext, runStarts, runLengths,
                        chunkPositions, slots, true);

                if (permute) {
                    permutedKeyIndices.setSize(preKeyIndices.size());
                    postPermutedKeyIndices.setSize(postKeyIndices.size());

                    LongPermuteKernel.permuteInput(preKeyIndices, chunkPositions, permutedKeyIndices);
                    LongPermuteKernel.permuteInput(postKeyIndices, chunkPositions, postPermutedKeyIndices);

                    usePreKeys = permutedKeyIndices;
                    usePostKeys = postPermutedKeyIndices;
                } else {
                    usePreKeys = (LongChunk) preKeyIndices;
                    usePostKeys = (LongChunk) postKeyIndices;
                }

                boolean anyOperatorModified = false;
                boolean firstOperator = true;
                setFalse(modifiedSlots, runStarts.size());

                for (int oi = 0; oi < ac.size(); ++oi) {
                    if (!ac.operators[oi].requiresRowKeys()) {
                        continue;
                    }
                    if (!firstOperator) {
                        setFalse(slotsModifiedByOperator, runStarts.size());
                    }
                    final int inputSlot = ac.inputSlot(oi);
                    if (inputSlot >= 0 && !chunkInitialized[inputSlot]) {
                        if (permute) {
                            valueChunks[inputSlot] = getAndPermuteChunk(ac.inputColumns[inputSlot],
                                    getContexts[inputSlot], preShiftChunkKeys, true,
                                    permuteKernels[inputSlot], chunkPositions, workingChunks[inputSlot]);
                            postValueChunks[inputSlot] = getAndPermuteChunk(ac.inputColumns[inputSlot],
                                    postGetContexts[inputSlot], postShiftChunkKeys,
                                    false, permuteKernels[inputSlot], chunkPositions, postWorkingChunks[inputSlot]);
                        } else {
                            valueChunks[inputSlot] = getChunk(ac.inputColumns[inputSlot], getContexts[inputSlot],
                                    preShiftChunkKeys, true);
                            postValueChunks[inputSlot] = getChunk(ac.inputColumns[inputSlot],
                                    postGetContexts[inputSlot], postShiftChunkKeys, false);
                        }
                        chunkInitialized[inputSlot] = true;
                    }
                    try {
                        ac.operators[oi].shiftChunk(bucketedContexts[oi],
                                inputSlot >= 0 ? valueChunks[inputSlot] : null,
                                inputSlot >= 0 ? postValueChunks[inputSlot] : null, usePreKeys,
                                usePostKeys, slots, runStarts, runLengths,
                                firstOperator ? modifiedSlots : slotsModifiedByOperator);
                    } catch (Exception ex) {
                        throw new AggregationOperatorException(
                                "Failed to shift data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                        + ", outputs=" + ac.operators[oi].getResultColumns().keySet(),
                                ex);
                    } catch (Error err) {
                        err.addSuppressed(new AggregationOperatorException(
                                "Failed to shift data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                        + ", outputs=" + ac.operators[oi].getResultColumns().keySet()));
                        throw err;
                    }

                    anyOperatorModified = updateModificationState(modifiedOperators, modifiedSlots,
                            slotsModifiedByOperator, anyOperatorModified, firstOperator, oi);
                    firstOperator = false;
                }

                if (anyOperatorModified) {
                    modifySlots(modifiedStatesBuilder, runStarts, slots, modifiedSlots);
                }
            }
        }

        private void doSameSlotModifies(@NotNull final RowSequence preShiftKeyIndicesToModify,
                @NotNull final RowSequence postShiftKeyIndicesToModify,
                final boolean supplyPostIndices, @NotNull final boolean[] operatorsToProcess,
                @NotNull final boolean[] operatorsToProcessIndicesOnly) {
            final boolean shifted = preShiftKeyIndicesToModify != postShiftKeyIndicesToModify;

            try (final RowSequence.Iterator preShiftIterator = preShiftKeyIndicesToModify.getRowSequenceIterator();
                    final RowSequence.Iterator postShiftIterator =
                            shifted ? postShiftKeyIndicesToModify.getRowSequenceIterator() : null) {
                final boolean[] chunkInitialized = new boolean[ac.size()];
                while (preShiftIterator.hasMore()) {
                    final RowSequence preShiftKeyIndicesChunk =
                            preShiftIterator.getNextRowSequenceWithLength(CHUNK_SIZE);
                    final RowSequence postShiftKeyIndicesChunk =
                            shifted ? postShiftIterator.getNextRowSequenceWithLength(CHUNK_SIZE)
                                    : preShiftKeyIndicesChunk;
                    sharedContext.reset();
                    postSharedContext.reset();
                    Arrays.fill(chunkInitialized, false);

                    incrementalStateManager.findModifications(pc, postShiftKeyIndicesChunk, reinterpretedKeySources,
                            slots);
                    final boolean permute = findSlotRuns(sortKernelContext, hashedRunContext, runStarts, runLengths,
                            chunkPositions, slots,
                            ac.requiresRunFinds(SKIP_RUN_FIND));

                    if (supplyPostIndices) {
                        if (permute) {
                            final LongChunk postKeyIndices =
                                    postShiftKeyIndicesChunk.asRowKeyChunk();
                            permutedKeyIndices.setSize(postKeyIndices.size());
                            LongPermuteKernel.permuteInput(postKeyIndices, chunkPositions, permutedKeyIndices);
                        } else {
                            postShiftKeyIndicesChunk.fillRowKeyChunk(permutedKeyIndices);
                        }
                    }

                    boolean anyOperatorModified = false;
                    boolean firstOperator = true;
                    setFalse(modifiedSlots, runStarts.size());

                    for (int oi = 0; oi < ac.size(); ++oi) {
                        if (!operatorsToProcessIndicesOnly[oi] && !operatorsToProcess[oi]) {
                            continue;
                        }

                        if (!firstOperator) {
                            setFalse(slotsModifiedByOperator, runStarts.size());
                        }

                        if (operatorsToProcessIndicesOnly[oi]) {
                            try {
                                ac.operators[oi].modifyRowKeys(bucketedContexts[oi], permutedKeyIndices, slots,
                                        runStarts,
                                        runLengths, firstOperator ? modifiedSlots : slotsModifiedByOperator);
                            } catch (Exception ex) {
                                throw new AggregationOperatorException(
                                        "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                                + ", outputs=" + ac.operators[oi].getResultColumns().keySet(),
                                        ex);
                            } catch (Error err) {
                                err.addSuppressed(new AggregationOperatorException(
                                        "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                                + ", outputs=" + ac.operators[oi].getResultColumns().keySet()));
                                throw err;
                            }
                        } else /* operatorsToProcess[oi] */ {
                            final int inputSlot = ac.inputSlot(oi);
                            if (inputSlot >= 0 && !chunkInitialized[inputSlot]) {
                                if (permute) {
                                    valueChunks[inputSlot] = getAndPermuteChunk(ac.inputColumns[inputSlot],
                                            getContexts[inputSlot],
                                            preShiftKeyIndicesChunk, true, permuteKernels[inputSlot], chunkPositions,
                                            workingChunks[inputSlot]);
                                    postValueChunks[inputSlot] =
                                            getAndPermuteChunk(ac.inputColumns[inputSlot], postGetContexts[inputSlot],
                                                    postShiftKeyIndicesChunk, false, permuteKernels[inputSlot],
                                                    chunkPositions,
                                                    postWorkingChunks[inputSlot]);
                                } else {
                                    valueChunks[inputSlot] =
                                            getChunk(ac.inputColumns[inputSlot], getContexts[inputSlot],
                                                    preShiftKeyIndicesChunk, true);
                                    postValueChunks[inputSlot] =
                                            getChunk(ac.inputColumns[inputSlot], postGetContexts[inputSlot],
                                                    postShiftKeyIndicesChunk, false);
                                }
                                chunkInitialized[inputSlot] = true;
                            }

                            try {
                                ac.operators[oi].modifyChunk(bucketedContexts[oi],
                                        inputSlot >= 0 ? valueChunks[inputSlot] : null,
                                        inputSlot >= 0 ? postValueChunks[inputSlot] : null, permutedKeyIndices, slots,
                                        runStarts, runLengths, firstOperator ? modifiedSlots : slotsModifiedByOperator);
                            } catch (Exception ex) {
                                throw new AggregationOperatorException(
                                        "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                                + ", outputs=" + ac.operators[oi].getResultColumns().keySet(),
                                        ex);
                            } catch (Error er) {
                                er.addSuppressed(new AggregationOperatorException(
                                        "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                                + ", outputs=" + ac.operators[oi].getResultColumns().keySet()));
                                throw er;
                            }
                        }

                        anyOperatorModified = updateModificationState(modifiedOperators, modifiedSlots,
                                slotsModifiedByOperator, anyOperatorModified, firstOperator, oi);
                        firstOperator = false;
                    }

                    if (anyOperatorModified) {
                        modifySlots(modifiedStatesBuilder, runStarts, slots, modifiedSlots);
                    }
                }
            }
        }

        private void doSameSlotModifyIndicesOnly(@NotNull final RowSequence postShiftKeyIndicesToModify,
                @NotNull final boolean[] operatorsToProcessIndicesOnly) {
            try (final RowSequence.Iterator postShiftIterator = postShiftKeyIndicesToModify.getRowSequenceIterator()) {
                while (postShiftIterator.hasMore()) {
                    final RowSequence postShiftKeyIndicesChunk =
                            postShiftIterator.getNextRowSequenceWithLength(CHUNK_SIZE);

                    incrementalStateManager.findModifications(pc, postShiftKeyIndicesChunk, reinterpretedKeySources,
                            slots);
                    final boolean permute = findSlotRuns(sortKernelContext, hashedRunContext, runStarts, runLengths,
                            chunkPositions, slots,
                            ac.requiresRunFinds(SKIP_RUN_FIND));

                    if (permute) {
                        final LongChunk postKeyIndices = postShiftKeyIndicesChunk.asRowKeyChunk();
                        permutedKeyIndices.setSize(postKeyIndices.size());
                        LongPermuteKernel.permuteInput(postKeyIndices, chunkPositions, permutedKeyIndices);
                    } else {
                        postShiftKeyIndicesChunk.fillRowKeyChunk(permutedKeyIndices);
                    }

                    boolean anyOperatorModified = false;
                    boolean firstOperator = true;
                    setFalse(modifiedSlots, runStarts.size());

                    for (int oi = 0; oi < ac.size(); ++oi) {
                        if (!operatorsToProcessIndicesOnly[oi]) {
                            continue;
                        }

                        if (!firstOperator) {
                            setFalse(slotsModifiedByOperator, runStarts.size());
                        }

                        try {
                            ac.operators[oi].modifyRowKeys(bucketedContexts[oi], permutedKeyIndices, slots, runStarts,
                                    runLengths, firstOperator ? modifiedSlots : slotsModifiedByOperator);
                        } catch (Exception ex) {
                            throw new AggregationOperatorException(
                                    "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                            + ", outputs=" + ac.operators[oi].getResultColumns().keySet(),
                                    ex);
                        } catch (Error err) {
                            err.addSuppressed(new AggregationOperatorException(
                                    "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                            + ", outputs=" + ac.operators[oi].getResultColumns().keySet()));
                            throw err;
                        }
                        anyOperatorModified = updateModificationState(modifiedOperators, modifiedSlots,
                                slotsModifiedByOperator, anyOperatorModified, firstOperator, oi);
                        firstOperator = false;
                    }

                    if (anyOperatorModified) {
                        modifySlots(modifiedStatesBuilder, runStarts, slots, modifiedSlots);
                    }
                }
            }
        }

        private static class ModifySplitResult implements SafeCloseable {

            /**
             * This is a partition of same-slot modifies for row keys that were not shifted. Needed for modifyChunk of
             * input-modified operators that require indices, since they handle the shifted same-slot modifies in
             * shiftChunk.
             */
            @Nullable
            private final RowSet unshiftedSameSlotIndices;
            /**
             * This is all of same-slot modified, with row keys in pre-shift space. Needed for modifyChunk of
             * input-modified operators that don't require indices.
             */
            @Nullable
            private final RowSet sameSlotIndicesPreShift;
            /**
             * This is all of same-slot modified, with row keys in post-shift space. Needed for modifyChunk of
             * input-modified operators that don't require indices, and for modifyRowKeys of operators that require
             * indices but don't have any inputs modified.
             */
            @Nullable
            private final RowSet sameSlotIndicesPostShift;
            /**
             * This is all key change modifies, with row keys in post-shift space. Needed for addChunk to process key
             * changes for all operators.
             */
            @NotNull
            private final RowSet keyChangeIndicesPostShift;

            private ModifySplitResult(@Nullable final RowSet unshiftedSameSlotIndices,
                    @Nullable final RowSet sameSlotIndicesPreShift,
                    @Nullable final RowSet sameSlotIndicesPostShift,
                    @NotNull final RowSet keyChangeIndicesPostShift) {
                this.unshiftedSameSlotIndices = unshiftedSameSlotIndices;
                this.sameSlotIndicesPreShift = sameSlotIndicesPreShift;
                this.sameSlotIndicesPostShift = sameSlotIndicesPostShift;
                this.keyChangeIndicesPostShift = keyChangeIndicesPostShift;
            }

            @Override
            public final void close() {
                if (unshiftedSameSlotIndices != null) {
                    unshiftedSameSlotIndices.close();
                }
                if (sameSlotIndicesPreShift != null) {
                    sameSlotIndicesPreShift.close();
                }
                if (sameSlotIndicesPostShift != null) {
                    sameSlotIndicesPostShift.close();
                }
                keyChangeIndicesPostShift.close();
            }
        }

        private ModifySplitResult splitKeyModificationsAndDoKeyChangeRemoves() {
            Require.requirement(keysModified, "keysModified");

            final boolean needUnshiftedSameSlotIndices = processShifts;
            final boolean needSameSlotIndicesPreShift = !processShifts && od.anyOperatorHasModifiedInputColumns;
            final boolean needSameSlotIndicesPostShift = !processShifts && (od.anyOperatorHasModifiedInputColumns
                    || od.anyOperatorWithoutModifiedInputColumnsRequiresIndices || keysModified);

            final RowSetBuilderSequential unshiftedSameSlotIndicesBuilder =
                    needUnshiftedSameSlotIndices ? RowSetFactory.builderSequential() : null;
            final RowSetBuilderSequential sameSlotIndicesPreShiftBuilder =
                    needSameSlotIndicesPreShift ? RowSetFactory.builderSequential() : null;
            final RowSetBuilderSequential sameSlotIndicesPostShiftBuilder =
                    needSameSlotIndicesPostShift ? RowSetFactory.builderSequential() : null;
            final RowSetBuilderSequential keyChangeIndicesPostShiftBuilder =
                    RowSetFactory.builderSequential();

            try (final RowSequence.Iterator modifiedPreShiftIterator =
                    upstream.getModifiedPreShift().getRowSequenceIterator();
                    final RowSequence.Iterator modifiedPostShiftIterator =
                            shifted ? upstream.modified().getRowSequenceIterator() : null;
                    final WritableIntChunk postSlots = WritableIntChunk.makeWritableChunk(buildChunkSize)) {

                // Hijacking postPermutedKeyIndices because it's not used in this loop; the rename hopefully makes the
                // code much clearer!
                final WritableLongChunk removedKeyIndices = postPermutedKeyIndices;

                while (modifiedPreShiftIterator.hasMore()) {
                    final RowSequence modifiedPreShiftChunk =
                            modifiedPreShiftIterator.getNextRowSequenceWithLength(CHUNK_SIZE);
                    final RowSequence modifiedPostShiftChunk =
                            shifted ? modifiedPostShiftIterator.getNextRowSequenceWithLength(CHUNK_SIZE)
                                    : modifiedPreShiftChunk;

                    incrementalStateManager.remove(pc, modifiedPreShiftChunk, reinterpretedKeySources, slots);
                    incrementalStateManager.add(bc, modifiedPostShiftChunk, reinterpretedKeySources, outputPosition,
                            postSlots);

                    final LongChunk preShiftIndices = modifiedPreShiftChunk.asRowKeyChunk();
                    final LongChunk postShiftIndices =
                            shifted ? modifiedPostShiftChunk.asRowKeyChunk() : preShiftIndices;

                    final int chunkSize = slots.size();
                    int numKeyChanges = 0;
                    for (int si = 0; si < chunkSize; ++si) {
                        final int previousSlot = slots.get(si);
                        final int currentSlot = postSlots.get(si);
                        final long previousIndex = preShiftIndices.get(si);
                        final long currentIndex = postShiftIndices.get(si);

                        if (previousSlot == currentSlot) {
                            if (previousIndex == currentIndex && needUnshiftedSameSlotIndices) {
                                unshiftedSameSlotIndicesBuilder.appendKey(currentIndex);
                            }
                            if (needSameSlotIndicesPreShift) {
                                sameSlotIndicesPreShiftBuilder.appendKey(previousIndex);
                            }
                            if (needSameSlotIndicesPostShift) {
                                sameSlotIndicesPostShiftBuilder.appendKey(currentIndex);
                            }
                        } else {
                            slots.set(numKeyChanges, previousSlot);
                            removedKeyIndices.set(numKeyChanges++, previousIndex);
                            keyChangeIndicesPostShiftBuilder.appendKey(currentIndex);
                        }
                    }
                    if (numKeyChanges > 0) {
                        slots.setSize(numKeyChanges);
                        removedKeyIndices.setSize(numKeyChanges);
                        try (final RowSequence keyIndicesToRemoveChunk = RowSequenceFactory
                                .wrapRowKeysChunkAsRowSequence(LongChunk.downcast(removedKeyIndices))) {
                            propagateRemovesToOperators(keyIndicesToRemoveChunk, slots);
                        }
                    }
                }
            }

            return new ModifySplitResult(
                    needUnshiftedSameSlotIndices ? unshiftedSameSlotIndicesBuilder.build() : null,
                    needSameSlotIndicesPreShift ? sameSlotIndicesPreShiftBuilder.build() : null,
                    needSameSlotIndicesPostShift ? sameSlotIndicesPostShiftBuilder.build() : null,
                    keyChangeIndicesPostShiftBuilder.build());
        }

        private RowSet getUnshiftedModifies() {
            Require.requirement(!keysModified, "!keysModified");
            Require.requirement(shifted, "shifted");
            return extractUnshiftedModifiesFromUpstream(upstream);
        }

        private static boolean updateModificationState(@NotNull final boolean[] modifiedOperators,
                @NotNull final WritableBooleanChunk modifiedSlots,
                @NotNull final BooleanChunk slotsModifiedByOperator, boolean operatorModified,
                final boolean firstOperator, final int operatorIndex) {
            final boolean chunkModifiedSlots;
            if (firstOperator) {
                chunkModifiedSlots = anyTrue(modifiedSlots);
                operatorModified = chunkModifiedSlots;
            } else {
                chunkModifiedSlots = orInto(slotsModifiedByOperator, modifiedSlots);
                operatorModified |= chunkModifiedSlots;
            }
            modifiedOperators[operatorIndex] |= chunkModifiedSlots;
            return operatorModified;
        }
    }

    private static RowSet extractUnshiftedModifiesFromUpstream(@NotNull final TableUpdate upstream) {
        final RowSetBuilderSequential unshiftedModifiesBuilder = RowSetFactory.builderSequential();

        try (final RowSequence.Iterator modifiedPreShiftIterator =
                upstream.getModifiedPreShift().getRowSequenceIterator();
                final RowSequence.Iterator modifiedPostShiftIterator = upstream.modified().getRowSequenceIterator()) {
            while (modifiedPreShiftIterator.hasMore()) {
                final RowSequence modifiedPreShiftChunk =
                        modifiedPreShiftIterator.getNextRowSequenceWithLength(CHUNK_SIZE);
                final RowSequence modifiedPostShiftChunk =
                        modifiedPostShiftIterator.getNextRowSequenceWithLength(CHUNK_SIZE);

                final LongChunk preShiftIndices = modifiedPreShiftChunk.asRowKeyChunk();
                final LongChunk postShiftIndices = modifiedPostShiftChunk.asRowKeyChunk();

                final int chunkSize = preShiftIndices.size();
                for (int ki = 0; ki < chunkSize; ++ki) {
                    final long previousIndex = preShiftIndices.get(ki);
                    final long currentIndex = postShiftIndices.get(ki);

                    if (previousIndex == currentIndex) {
                        unshiftedModifiesBuilder.appendKey(currentIndex);
                    }
                }
            }
        }

        return unshiftedModifiesBuilder.build();
    }

    private static void extractDownstreamModifiedColumnSet(@NotNull final TableUpdateImpl downstream,
            @NotNull final ModifiedColumnSet resultModifiedColumnSet,
            @NotNull final boolean[] modifiedOperators,
            @NotNull final ModifiedColumnSet updateUpstreamModifiedColumnSet,
            @NotNull final UnaryOperator[] resultModifiedColumnSetFactories) {
        if (downstream.modified().isNonempty()) {
            downstream.modifiedColumnSet = resultModifiedColumnSet;
            downstream.modifiedColumnSet().clear();
            for (int oi = 0; oi < modifiedOperators.length; ++oi) {
                if (modifiedOperators[oi]) {
                    downstream.modifiedColumnSet()
                            .setAll(resultModifiedColumnSetFactories[oi].apply(updateUpstreamModifiedColumnSet));
                }
            }
        } else {
            downstream.modifiedColumnSet = ModifiedColumnSet.EMPTY;
        }
        if (downstream.modifiedColumnSet().empty() && downstream.modified().isNonempty()) {
            downstream.modified().close();
            downstream.modified = RowSetFactory.empty();
        }
    }

    private static class OperatorDivision {

        private final boolean anyOperatorHasModifiedInputColumns;
        private final boolean[] operatorsWithModifiedInputColumns;

        private final boolean anyOperatorWithModifiedInputColumnsIgnoresIndices;
        private final boolean[] operatorsWithModifiedInputColumnsThatIgnoreIndices;

        private final boolean anyOperatorWithoutModifiedInputColumnsRequiresIndices;
        private final boolean[] operatorsWithoutModifiedInputColumnsThatRequireIndices;

        private final boolean[] operatorsThatRequireIndices;

        private OperatorDivision(@NotNull final AggregationContext ac,
                final boolean upstreamModified,
                @NotNull final ModifiedColumnSet updateUpstreamModifiedColumnSet,
                @NotNull final ModifiedColumnSet[] operatorInputUpstreamModifiedColumnSets) {
            operatorsThatRequireIndices = new boolean[ac.size()];
            for (int oi = 0; oi < ac.size(); ++oi) {
                operatorsThatRequireIndices[oi] = ac.operators[oi].requiresRowKeys();
            }

            operatorsWithModifiedInputColumns = new boolean[ac.size()];
            operatorsWithModifiedInputColumnsThatIgnoreIndices = new boolean[ac.size()];
            operatorsWithoutModifiedInputColumnsThatRequireIndices = new boolean[ac.size()];
            boolean anyOperatorHasModifiedInputColumnsTemp = false;
            boolean anyOperatorWithModifiedInputColumnsIgnoresIndicesTemp = false;
            boolean anyOperatorWithoutModifiedInputColumnsRequiresIndicesTemp = false;
            if (upstreamModified) {
                for (int oi = 0; oi < ac.size(); ++oi) {

                    if (updateUpstreamModifiedColumnSet.containsAny(operatorInputUpstreamModifiedColumnSets[oi])) {
                        operatorsWithModifiedInputColumns[oi] = true;
                        anyOperatorHasModifiedInputColumnsTemp = true;
                        if (!ac.operators[oi].requiresRowKeys()) {
                            operatorsWithModifiedInputColumnsThatIgnoreIndices[oi] = true;
                            anyOperatorWithModifiedInputColumnsIgnoresIndicesTemp = true;
                        }
                    } else if (ac.operators[oi].requiresRowKeys()) {
                        operatorsWithoutModifiedInputColumnsThatRequireIndices[oi] = true;
                        anyOperatorWithoutModifiedInputColumnsRequiresIndicesTemp = true;
                    }
                }
            }

            anyOperatorHasModifiedInputColumns = anyOperatorHasModifiedInputColumnsTemp;
            anyOperatorWithModifiedInputColumnsIgnoresIndices = anyOperatorWithModifiedInputColumnsIgnoresIndicesTemp;
            anyOperatorWithoutModifiedInputColumnsRequiresIndices =
                    anyOperatorWithoutModifiedInputColumnsRequiresIndicesTemp;
        }
    }

    private static void processUpstreamShifts(TableUpdate upstream, RowSet useIndex,
            WritableLongChunk preKeyIndices, WritableLongChunk postKeyIndices,
            Runnable applyChunkedShift) {
        RowSet.SearchIterator postOkForward = null;
        RowSet.SearchIterator postOkReverse = null;

        boolean lastPolarityReversed = false; // the initial value doesn't matter, because we'll just have a noop apply
                                              // in the worst case
        int writePosition = resetWritePosition(lastPolarityReversed, preKeyIndices, postKeyIndices);

        final RowSetShiftData.Iterator shiftIt = upstream.shifted().applyIterator();
        while (shiftIt.hasNext()) {
            shiftIt.next();

            final boolean polarityReversed = shiftIt.polarityReversed();
            if (polarityReversed != lastPolarityReversed) {
                // if our polarity changed, we must flush out the shifts that are pending
                maybeApplyChunkedShift(applyChunkedShift, preKeyIndices, postKeyIndices, lastPolarityReversed,
                        writePosition);
                writePosition = resetWritePosition(polarityReversed, preKeyIndices, postKeyIndices);
            }

            final long delta = shiftIt.shiftDelta();

            final long endRange = shiftIt.endRange() + delta;
            final long beginRange = shiftIt.beginRange() + delta;

            if (polarityReversed) {
                // we must apply these shifts reversed
                if (postOkReverse == null) {
                    postOkReverse = useIndex.reverseIterator();
                }
                if (postOkReverse.advance(endRange)) {
                    long idx;
                    while ((idx = postOkReverse.currentValue()) >= beginRange) {
                        postKeyIndices.set(--writePosition, idx);
                        preKeyIndices.set(writePosition, idx - delta);

                        if (writePosition == 0) {
                            // once we fill a chunk, we must process the shifts
                            maybeApplyChunkedShift(applyChunkedShift, preKeyIndices, postKeyIndices, polarityReversed,
                                    writePosition);
                            writePosition = resetWritePosition(polarityReversed, preKeyIndices, postKeyIndices);
                        }

                        if (postOkReverse.hasNext()) {
                            postOkReverse.nextLong();
                        } else {
                            break;
                        }
                    }
                }
            } else {
                if (postOkReverse != null) {
                    postOkReverse.close();
                    postOkReverse = null;
                }
                if (postOkForward == null) {
                    postOkForward = useIndex.searchIterator();
                }
                // we can apply these in a forward direction as normal, we just need to accumulate into our key chunks
                if (postOkForward.advance(beginRange)) {
                    long idx;
                    while ((idx = postOkForward.currentValue()) <= endRange) {
                        postKeyIndices.add(idx);
                        preKeyIndices.add(idx - delta);

                        if (postKeyIndices.size() == postKeyIndices.capacity()) {
                            // once we fill a chunk, we must process the shifts
                            maybeApplyChunkedShift(applyChunkedShift, preKeyIndices, postKeyIndices, polarityReversed,
                                    writePosition);
                            writePosition = resetWritePosition(polarityReversed, preKeyIndices, postKeyIndices);
                        }

                        if (postOkForward.hasNext()) {
                            postOkForward.nextLong();
                        } else {
                            break;
                        }
                    }

                }
            }
            lastPolarityReversed = polarityReversed;
        }
        // after we are done, we should process the shift
        maybeApplyChunkedShift(applyChunkedShift, preKeyIndices, postKeyIndices, lastPolarityReversed, writePosition);
        // close our iterators
        if (postOkReverse != null) {
            postOkReverse.close();
        }
        if (postOkForward != null) {
            postOkForward.close();
        }
    }

    private static int resetWritePosition(boolean polarityReversed, WritableLongChunk preKeyIndices,
            WritableLongChunk postKeyIndices) {
        if (polarityReversed) {
            postKeyIndices.setSize(postKeyIndices.capacity());
            if (preKeyIndices != null) {
                preKeyIndices.setSize(postKeyIndices.capacity());
            }
            return postKeyIndices.capacity();
        } else {
            postKeyIndices.setSize(0);
            if (preKeyIndices != null) {
                preKeyIndices.setSize(0);
            }
            return 0;
        }
    }

    private static void maybeApplyChunkedShift(Runnable applyChunkedShift,
            WritableLongChunk preKeyIndices, WritableLongChunk postKeyIndices,
            boolean polarityReversed, int writePosition) {
        if (polarityReversed) {
            int chunkSize = postKeyIndices.capacity();
            if (writePosition == chunkSize) {
                return;
            }
            if (writePosition > 0) {
                postKeyIndices.copyFromTypedChunk(postKeyIndices, writePosition, 0, chunkSize - writePosition);
                postKeyIndices.setSize(chunkSize - writePosition);
                if (preKeyIndices != null) {
                    preKeyIndices.copyFromTypedChunk(preKeyIndices, writePosition, 0, chunkSize - writePosition);
                    preKeyIndices.setSize(chunkSize - writePosition);
                }
            }
        } else {
            if (postKeyIndices.size() == 0) {
                return;
            }
        }
        applyChunkedShift.run();
    }

    private static void setFalse(WritableBooleanChunk modifiedSlots, int size) {
        modifiedSlots.fillWithValue(0, size, false);
        modifiedSlots.setSize(size);
    }

    private static boolean orInto(BooleanChunk operatorSlots, WritableBooleanChunk modifiedSlots) {
        boolean anyTrue = false;
        for (int ii = 0; ii < operatorSlots.size(); ++ii) {
            if (operatorSlots.get(ii)) {
                anyTrue = true;
                modifiedSlots.set(ii, true);
            }
        }
        return anyTrue;
    }

    private static boolean anyTrue(BooleanChunk operatorSlots) {
        for (int ii = 0; ii < operatorSlots.size(); ++ii) {
            if (operatorSlots.get(ii)) {
                return true;
            }
        }
        return false;
    }

    /**
     * @return true if we must permute the inputs
     */
    private static boolean findSlotRuns(
            IntIntTimsortKernel.IntIntSortKernelContext sortKernelContext,
            HashedRunFinder.HashedRunContext hashedRunContext,
            WritableIntChunk runStarts, WritableIntChunk runLengths,
            WritableIntChunk chunkPosition, WritableIntChunk slots,
            boolean findRuns) {
        if (!findRuns) {
            chunkPosition.setSize(slots.size());
            ChunkUtils.fillInOrder(chunkPosition);
            IntFindRunsKernel.findRunsSingles(slots, runStarts, runLengths);
            return false;
        } else if (HASHED_RUN_FIND) {
            return HashedRunFinder.findRunsHashed(hashedRunContext, runStarts, runLengths, chunkPosition, slots);
        } else {
            chunkPosition.setSize(slots.size());
            ChunkUtils.fillInOrder(chunkPosition);
            IntIntTimsortKernel.sort(sortKernelContext, chunkPosition, slots);
            IntFindRunsKernel.findRunsSingles(slots, runStarts, runLengths);
            return true;
        }
    }

    /**
     * Get values from the inputColumn, and permute them into workingChunk.
     */
    private static Chunk getAndPermuteChunk(ChunkSource.WithPrev inputColumn,
            ChunkSource.GetContext getContext,
            RowSequence chunkOk, boolean usePrev, PermuteKernel permuteKernel, IntChunk chunkPosition,
            WritableChunk workingChunk) {
        final Chunk values = getChunk(inputColumn, getContext, chunkOk, usePrev);

        // permute the chunk based on the chunkPosition, so that we have values from a slot together
        if (values != null) {
            workingChunk.setSize(values.size());
            permuteKernel.permuteInput(values, chunkPosition, workingChunk);
        }

        return workingChunk;
    }

    @Nullable
    private static Chunk getChunk(ChunkSource.WithPrev inputColumn,
            ChunkSource.GetContext getContext, RowSequence chunkOk, boolean usePrev) {
        final Chunk values;
        if (inputColumn == null) {
            values = null;
        } else if (usePrev) {
            values = inputColumn.getPrevChunk(getContext, chunkOk);
        } else {
            values = inputColumn.getChunk(getContext, chunkOk);
        }
        return values;
    }

    private static void modifySlots(RowSetBuilderRandom modifiedBuilder, IntChunk runStarts,
            WritableIntChunk slots, BooleanChunk modified) {
        int outIndex = 0;
        for (int runIndex = 0; runIndex < runStarts.size(); ++runIndex) {
            if (modified.get(runIndex)) {
                final int slotStart = runStarts.get(runIndex);
                final int slot = slots.get(slotStart);
                slots.set(outIndex++, slot);
            }
        }
        slots.setSize(outIndex);
        modifiedBuilder.addRowKeysChunk(slots);
    }

    @NotNull
    private static QueryTable staticGroupedAggregation(QueryTable withView, String keyName, ColumnSource keySource,
            AggregationContext ac) {
        final Pair> groupKeyIndexTable;
        final Map grouping = RowSetIndexer.of(withView.getRowSet()).getGrouping(keySource);
        // noinspection unchecked
        groupKeyIndexTable = GroupingUtils.groupingToFlatSources((ColumnSource) keySource, grouping);
        final int responsiveGroups = grouping.size();

        final Map> resultColumnSourceMap = new LinkedHashMap<>();
        resultColumnSourceMap.put(keyName, groupKeyIndexTable.first);
        ac.getResultColumns(resultColumnSourceMap);

        doGroupedAddition(ac, groupKeyIndexTable.second::get, responsiveGroups, CHUNK_SIZE);

        final QueryTable result = new QueryTable(RowSetFactory.flat(responsiveGroups).toTracking(),
                resultColumnSourceMap);
        ac.propagateInitialStateToOperators(result, responsiveGroups);

        ac.supplyRowLookup(() -> {
            final TObjectIntMap keyToSlot = new TObjectIntHashMap<>(
                    responsiveGroups, Constants.DEFAULT_LOAD_FACTOR, DEFAULT_UNKNOWN_ROW);
            final MutableInt slotNumber = new MutableInt(0);
            grouping.keySet().forEach(k -> keyToSlot.put(k, slotNumber.getAndIncrement()));
            return keyToSlot::get;
        });

        final QueryTable finalResult = ac.transformResult(result);
        if (finalResult.getRowSet().isFlat()) {
            finalResult.setFlat();
        }
        return finalResult;
    }

    private static void doGroupedAddition(
            @NotNull final AggregationContext ac,
            @NotNull final LongFunction groupIndexToRowSet,
            final int responsiveGroups,
            final int chunkSize) {
        final boolean indicesRequired = ac.requiresIndices();

        final ColumnSource.GetContext[] getContexts = new ColumnSource.GetContext[ac.size()];
        final IterativeChunkedAggregationOperator.SingletonContext[] operatorContexts =
                new IterativeChunkedAggregationOperator.SingletonContext[ac.size()];
        try (final SafeCloseableArray ignored = new SafeCloseableArray<>(getContexts);
                final SafeCloseable ignored2 = new SafeCloseableArray<>(operatorContexts);
                final SharedContext sharedContext = SharedContext.makeSharedContext()) {
            ac.ensureCapacity(responsiveGroups);
            ac.initializeGetContexts(sharedContext, getContexts, chunkSize);
            ac.initializeSingletonContexts(operatorContexts, chunkSize);

            final boolean unchunked = !ac.requiresInputs() && ac.unchunkedIndices();
            if (unchunked) {
                for (int ii = 0; ii < responsiveGroups; ++ii) {
                    final RowSet rowSet = groupIndexToRowSet.apply(ii);
                    for (int oi = 0; oi < ac.size(); ++oi) {
                        ac.operators[oi].addRowSet(operatorContexts[oi], rowSet, ii);
                    }
                }
            } else {
                // noinspection unchecked
                final Chunk[] workingChunks = new Chunk[ac.size()];
                for (int ii = 0; ii < responsiveGroups; ++ii) {
                    final RowSet rowSet = groupIndexToRowSet.apply(ii);
                    try (final RowSequence.Iterator rsIt = rowSet.getRowSequenceIterator()) {
                        do {
                            final RowSequence chunkRows = rsIt.getNextRowSequenceWithLength(chunkSize);
                            final int chunkRowsSize = chunkRows.intSize();
                            final LongChunk keyIndices =
                                    indicesRequired ? chunkRows.asRowKeyChunk() : null;
                            sharedContext.reset();

                            Arrays.fill(workingChunks, null);

                            for (int oi = 0; oi < ac.size(); ++oi) {
                                final int inputSlot = ac.inputSlot(oi);
                                if (inputSlot == oi) {
                                    workingChunks[inputSlot] = ac.inputColumns[oi] == null ? null
                                            : ac.inputColumns[oi].getChunk(getContexts[oi], chunkRows);
                                }
                                try {
                                    ac.operators[oi].addChunk(operatorContexts[oi], chunkRowsSize,
                                            inputSlot < 0 ? null : workingChunks[inputSlot], keyIndices, ii);
                                } catch (Exception ex) {
                                    throw new AggregationOperatorException(
                                            "Failed to add data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                                    + ", outputs=" + ac.operators[oi].getResultColumns().keySet(),
                                            ex);
                                } catch (Error err) {
                                    err.addSuppressed(new AggregationOperatorException(
                                            "Failed to add data, inputcolumns=" + Arrays.toString(ac.inputNames[oi])
                                                    + ", outputs=" + ac.operators[oi].getResultColumns().keySet()));
                                    throw err;
                                }
                            }
                        } while (rsIt.hasMore());
                    }
                }
            }
        }
    }

    private static OperatorAggregationStateManager initialKeyTableAddition(
            @NotNull final AggregationControl control,
            @NotNull final Table initialKeys,
            @NotNull final String[] keyColumnNames,
            @NotNull final AggregationContext ac,
            @NotNull final MutableInt outputPosition,
            @NotNull final Supplier stateManagerSupplier) {

        // This logic is duplicative of the logic in the main aggregation function, but it's hard to consolidate
        // further. A better strategy might be to do a selectDistinct first, but that would result in more hash table
        // inserts.
        final ColumnSource[] keySources = Arrays.stream(keyColumnNames)
                .map(initialKeys::getColumnSource)
                .toArray(ColumnSource[]::new);
        final ColumnSource[] reinterpretedKeySources = Arrays.stream(keyColumnNames)
                .map(initialKeys::getColumnSource)
                .map(ReinterpretUtils::maybeConvertToPrimitive)
                .toArray(ColumnSource[]::new);
        final boolean useGroupingAllowed = control.considerGrouping(initialKeys, keySources)
                && keySources.length == 1
                && reinterpretedKeySources[0] == keySources[0];

        final OperatorAggregationStateManager stateManager;
        if (initialKeys.isRefreshing()) {
            try (final SafeCloseable ignored = ExecutionContext.getContext().withUpdateGraph(
                    initialKeys.getUpdateGraph()).open()) {
                final MutableObject stateManagerHolder = new MutableObject<>();
                ConstructSnapshot.callDataSnapshotFunction(
                        "InitialKeyTableSnapshot-" + System.identityHashCode(initialKeys) + ": ",
                        ConstructSnapshot.makeSnapshotControl(false, true, (NotificationStepSource) initialKeys),
                        (final boolean usePrev, final long beforeClockValue) -> {
                            stateManagerHolder.setValue(makeInitializedStateManager(
                                    initialKeys, reinterpretedKeySources, ac, outputPosition, stateManagerSupplier,
                                    useGroupingAllowed, usePrev));
                            return true;
                        });
                stateManager = stateManagerHolder.getValue();
            }
        } else {
            stateManager = makeInitializedStateManager(initialKeys, reinterpretedKeySources,
                    ac, outputPosition, stateManagerSupplier, useGroupingAllowed, false);
        }
        try (final RowSet empty = RowSetFactory.empty()) {
            doGroupedAddition(ac, gi -> empty, outputPosition.intValue(), 0);
        }
        return stateManager;
    }

    private static OperatorAggregationStateManager makeInitializedStateManager(
            @NotNull final Table initialKeys,
            @NotNull ColumnSource[] reinterpretedKeySources,
            @NotNull final AggregationContext ac,
            @NotNull final MutableInt outputPosition,
            @NotNull final Supplier stateManagerSupplier,
            final boolean useGroupingAllowed,
            final boolean usePrev) {
        outputPosition.setValue(0);
        final OperatorAggregationStateManager stateManager = stateManagerSupplier.get();

        if (initialKeys.isEmpty()) {
            return stateManager;
        }

        final ColumnSource[] keyColumnsToInsert;
        final boolean closeRowsToInsert;
        final RowSequence rowsToInsert;
        final RowSetIndexer groupingIndexer = useGroupingAllowed && (!initialKeys.isRefreshing() || !usePrev)
                ? RowSetIndexer.of(initialKeys.getRowSet())
                : null;
        if (groupingIndexer != null && groupingIndexer.hasGrouping(reinterpretedKeySources[0])) {
            final ColumnSource groupedSource = reinterpretedKeySources[0];
            final Map grouping = groupingIndexer.getGrouping(groupedSource);
            // noinspection unchecked
            keyColumnsToInsert = new ColumnSource[] {
                    GroupingUtils.groupingKeysToImmutableFlatSource(groupedSource, grouping)};
            closeRowsToInsert = true;
            // noinspection resource
            rowsToInsert = RowSequenceFactory.forRange(0, grouping.size() - 1);
        } else {
            keyColumnsToInsert = reinterpretedKeySources;
            closeRowsToInsert = usePrev;
            rowsToInsert = usePrev ? initialKeys.getRowSet().copyPrev() : initialKeys.getRowSet();
        }

        final int chunkSize = chunkSize(rowsToInsert.size());
        try (final SafeCloseable ignored = closeRowsToInsert ? rowsToInsert : null;
                final SafeCloseable bc = stateManager.makeAggregationStateBuildContext(keyColumnsToInsert, chunkSize);
                final RowSequence.Iterator rowsIterator = rowsToInsert.getRowSequenceIterator();
                final WritableIntChunk outputPositions = WritableIntChunk.makeWritableChunk(chunkSize)) {
            while (rowsIterator.hasMore()) {
                final RowSequence chunkRows = rowsIterator.getNextRowSequenceWithLength(chunkSize);
                stateManager.add(bc, chunkRows, keyColumnsToInsert, outputPosition, outputPositions);
            }
        }
        return stateManager;
    }

    private static void initialBucketedKeyAddition(QueryTable input,
            ColumnSource[] reinterpretedKeySources,
            AggregationContext ac,
            PermuteKernel[] permuteKernels,
            OperatorAggregationStateManager stateManager,
            MutableInt outputPosition,
            RowSetBuilderRandom initialRowsBuilder,
            boolean usePrev) {
        final boolean findRuns = ac.requiresRunFinds(SKIP_RUN_FIND);

        final ChunkSource.GetContext[] getContexts = new ChunkSource.GetContext[ac.size()];
        // noinspection unchecked
        final WritableChunk[] workingChunks = findRuns ? new WritableChunk[ac.size()] : null;
        final Chunk[] valueChunks = new Chunk[ac.size()];
        final IterativeChunkedAggregationOperator.BucketedContext[] bucketedContexts =
                new IterativeChunkedAggregationOperator.BucketedContext[ac.size()];

        final ColumnSource[] buildSources;
        if (usePrev) {
            buildSources = Arrays.stream(reinterpretedKeySources)
                    .map((UnaryOperator>) PrevColumnSource::new).toArray(ColumnSource[]::new);
        } else {
            buildSources = reinterpretedKeySources;
        }

        final RowSet rowSet = usePrev ? input.getRowSet().copyPrev() : input.getRowSet();

        if (rowSet.isEmpty()) {
            return;
        }

        final int chunkSize = chunkSize(rowSet.size());

        try (final SafeCloseable bc = stateManager.makeAggregationStateBuildContext(buildSources, chunkSize);
                final SafeCloseable ignored1 = usePrev ? rowSet : null;
                final SafeCloseable ignored2 = new SafeCloseableArray<>(getContexts);
                final SafeCloseable ignored3 = findRuns ? new SafeCloseableArray<>(workingChunks) : null;
                final SafeCloseable ignored4 = new SafeCloseableArray<>(bucketedContexts);
                final RowSequence.Iterator rsIt = rowSet.getRowSequenceIterator();
                final WritableIntChunk outputPositions = WritableIntChunk.makeWritableChunk(chunkSize);
                final WritableIntChunk chunkPosition = WritableIntChunk.makeWritableChunk(chunkSize);
                final SharedContext sharedContext = SharedContext.makeSharedContext();
                final IntIntTimsortKernel.IntIntSortKernelContext sortKernelContext =
                        !findRuns || HASHED_RUN_FIND ? null : IntIntTimsortKernel.createContext(chunkSize);
                final HashedRunFinder.HashedRunContext hashedRunContext =
                        !findRuns || !HASHED_RUN_FIND ? null : new HashedRunFinder.HashedRunContext(chunkSize);
                final WritableIntChunk runStarts = WritableIntChunk.makeWritableChunk(chunkSize);
                final WritableIntChunk runLengths = WritableIntChunk.makeWritableChunk(chunkSize);
                final WritableLongChunk permutedKeyIndices =
                        ac.requiresIndices() ? WritableLongChunk.makeWritableChunk(chunkSize) : null;
                final WritableBooleanChunk unusedModifiedSlots =
                        WritableBooleanChunk.makeWritableChunk(chunkSize)) {
            ac.initializeGetContexts(sharedContext, getContexts, chunkSize);
            if (findRuns) {
                ac.initializeWorkingChunks(workingChunks, chunkSize);
            }
            ac.initializeBucketedContexts(bucketedContexts, chunkSize);

            while (rsIt.hasMore()) {
                final RowSequence chunkOk = rsIt.getNextRowSequenceWithLength(chunkSize);
                sharedContext.reset();

                stateManager.add(bc, chunkOk, buildSources, outputPosition, outputPositions);
                if (initialRowsBuilder != null) {
                    initialRowsBuilder.addRowKeysChunk(outputPositions);
                }

                ac.ensureCapacity(outputPosition.intValue());

                final boolean permute = findSlotRuns(sortKernelContext, hashedRunContext, runStarts, runLengths,
                        chunkPosition, outputPositions,
                        findRuns);

                if (permutedKeyIndices != null) {
                    if (permute) {
                        final LongChunk keyIndices = chunkOk.asRowKeyChunk();
                        permutedKeyIndices.setSize(keyIndices.size());
                        LongPermuteKernel.permuteInput(keyIndices, chunkPosition, permutedKeyIndices);
                    } else {
                        chunkOk.fillRowKeyChunk(permutedKeyIndices);
                    }
                }

                for (int ii = 0; ii < ac.size(); ++ii) {
                    final int inputSlot = ac.inputSlot(ii);
                    if (ii == inputSlot) {
                        if (!permute) {
                            valueChunks[inputSlot] = getChunk(ac.inputColumns[ii], getContexts[ii], chunkOk, usePrev);
                        } else {
                            assert workingChunks != null;
                            valueChunks[inputSlot] =
                                    getAndPermuteChunk(ac.inputColumns[ii], getContexts[ii], chunkOk, usePrev,
                                            permuteKernels[ii], chunkPosition, workingChunks[ii]);
                        }
                    }
                    try {
                        ac.operators[ii].addChunk(bucketedContexts[ii],
                                inputSlot >= 0 ? valueChunks[inputSlot] : null,
                                permutedKeyIndices, outputPositions, runStarts, runLengths, unusedModifiedSlots);
                    } catch (Exception ex) {
                        throw new AggregationOperatorException(
                                "Failed to add data, inputcolumns=" + Arrays.toString(ac.inputNames[ii]) + ", outputs="
                                        + ac.operators[ii].getResultColumns().keySet(),
                                ex);
                    } catch (Error err) {
                        err.addSuppressed(new AggregationOperatorException(
                                "Failed to add data, inputcolumns=" + Arrays.toString(ac.inputNames[ii]) + ", outputs="
                                        + ac.operators[ii].getResultColumns().keySet()));
                        throw err;
                    }
                }
            }
        }
    }

    private static void initialGroupedKeyAddition(QueryTable input,
            ColumnSource[] reinterpretedKeySources,
            AggregationContext ac,
            OperatorAggregationStateManager stateManager,
            MutableInt outputPosition,
            RowSetBuilderRandom initialRowsBuilder,
            boolean usePrev) {
        final Pair> groupKeyIndexTable;
        final RowSetIndexer indexer = RowSetIndexer.of(input.getRowSet());
        final Map grouping = usePrev ? indexer.getPrevGrouping(reinterpretedKeySources[0])
                : indexer.getGrouping(reinterpretedKeySources[0]);
        // noinspection unchecked
        groupKeyIndexTable =
                GroupingUtils.groupingToFlatSources((ColumnSource) reinterpretedKeySources[0], grouping);
        final int responsiveGroups = grouping.size();

        if (responsiveGroups == 0) {
            return;
        }

        ac.ensureCapacity(responsiveGroups);

        final ColumnSource[] groupedFlatKeySource = {groupKeyIndexTable.first};

        try (final SafeCloseable bc =
                stateManager.makeAggregationStateBuildContext(groupedFlatKeySource, responsiveGroups);
                final RowSequence rs = RowSequenceFactory.forRange(0, responsiveGroups - 1);
                final RowSequence.Iterator rsIt = rs.getRowSequenceIterator();
                final WritableIntChunk outputPositions =
                        WritableIntChunk.makeWritableChunk(responsiveGroups)) {
            while (rsIt.hasMore()) {
                final RowSequence chunkOk = rsIt.getNextRowSequenceWithLength(CHUNK_SIZE);
                stateManager.add(bc, chunkOk, groupedFlatKeySource, outputPosition, outputPositions);
                if (initialRowsBuilder != null) {
                    initialRowsBuilder.addRowKeysChunk(outputPositions);
                }
            }
            Assert.eq(outputPosition.intValue(), "outputPosition.intValue()", responsiveGroups, "responsiveGroups");
        }

        doGroupedAddition(ac, groupKeyIndexTable.second::get, responsiveGroups, CHUNK_SIZE);
    }

    private static RowSet makeNewStatesRowSet(final int first, final int last) {
        return first > last ? RowSetFactory.empty() : RowSetFactory.fromRange(first, last);
    }

    private static void copyKeyColumns(ColumnSource[] keyColumnsRaw, WritableColumnSource[] keyColumnsCopied,
            final RowSet copyValues) {
        if (copyValues.isEmpty()) {
            return;
        }
        final int chunkSize = chunkSize(copyValues.size());
        final ColumnSource.GetContext[] getContext = new ColumnSource.GetContext[keyColumnsRaw.length];
        final ChunkSink.FillFromContext[] fillFromContexts =
                new ChunkSink.FillFromContext[keyColumnsRaw.length];
        try (final RowSequence.Iterator rsIt = copyValues.getRowSequenceIterator();
                final SharedContext sharedContext = SharedContext.makeSharedContext();
                final SafeCloseableArray ignored = new SafeCloseableArray<>(getContext);
                final SafeCloseableArray ignored2 = new SafeCloseableArray<>(fillFromContexts)) {
            for (int ii = 0; ii < keyColumnsRaw.length; ++ii) {
                getContext[ii] = keyColumnsRaw[ii].makeGetContext(chunkSize, sharedContext);
                fillFromContexts[ii] = keyColumnsCopied[ii].makeFillFromContext(chunkSize);
                keyColumnsCopied[ii].ensureCapacity(copyValues.lastRowKey() + 1);
            }

            while (rsIt.hasMore()) {
                final RowSequence chunkOk = rsIt.getNextRowSequenceWithLength(chunkSize);
                sharedContext.reset();
                for (int ci = 0; ci < keyColumnsRaw.length; ci++) {
                    final Chunk values = keyColumnsRaw[ci].getChunk(getContext[ci], chunkOk);
                    keyColumnsCopied[ci].fillFromChunk(fillFromContexts[ci], values, chunkOk);
                }
            }
        }
    }

    private static QueryTable noKeyAggregation(
            @Nullable final OperationSnapshotControl snapshotControl,
            @NotNull final AggregationContextFactory aggregationContextFactory,
            @NotNull final QueryTable table,
            final boolean preserveEmpty,
            final boolean usePrev) {

        final AggregationContext ac = aggregationContextFactory.makeAggregationContext(table, false);
        final Map> resultColumnSourceMap = new LinkedHashMap<>();
        ac.getResultColumns(resultColumnSourceMap);

        final boolean[] allColumns = new boolean[ac.size()];
        Arrays.fill(allColumns, true);

        // We intentionally update the 0 key even if we have no rows, so we'd better have capacity for it.
        ac.ensureCapacity(1);

        // we don't actually care about the modified columns here and it will never set anything to false, so it is safe
        // to use allColumns as the modified columns parameter
        final IterativeChunkedAggregationOperator.SingletonContext[] opContexts =
                new IterativeChunkedAggregationOperator.SingletonContext[ac.size()];
        final RowSet rowSet = usePrev ? table.getRowSet().copyPrev() : table.getRowSet();
        final int initialResultSize;
        try (final SafeCloseable ignored1 = new SafeCloseableArray<>(opContexts);
                final SafeCloseable ignored2 = usePrev ? rowSet : null) {
            initialResultSize = preserveEmpty || rowSet.size() != 0 ? 1 : 0;
            ac.initializeSingletonContexts(opContexts, rowSet.size());
            doNoKeyAddition(rowSet, ac, opContexts, allColumns, usePrev, allColumns);
        }

        final QueryTable result = new QueryTable(RowSetFactory.flat(initialResultSize).toTracking(),
                resultColumnSourceMap);
        // always will create one result for zerokey
        ac.propagateInitialStateToOperators(result, 1);

        if (table.isRefreshing()) {
            ac.startTrackingPrevValues();

            final boolean isBlink = table.isBlink();
            final TableUpdateListener listener =
                    new BaseTable.ListenerImpl("groupBy(" + aggregationContextFactory + ")", table, result) {

                        final ModifiedColumnSet[] inputModifiedColumnSet = ac.getInputModifiedColumnSets(table);
                        final UnaryOperator[] resultModifiedColumnSetFactories =
                                ac.initializeRefreshing(result, this);

                        int lastSize = initialResultSize;
                        int statesCreated = initialResultSize;

                        @Override
                        public void onUpdate(@NotNull final TableUpdate upstream) {
                            final TableUpdate upstreamToUse = isBlink ? adjustForBlinkTable(upstream) : upstream;
                            if (upstreamToUse.empty()) {
                                return;
                            }
                            processNoKeyUpdate(upstreamToUse);
                        }

                        private void processNoKeyUpdate(@NotNull final TableUpdate upstream) {
                            ac.resetOperatorsForStep(upstream, 1);

                            final ModifiedColumnSet upstreamModifiedColumnSet =
                                    upstream.modified().isEmpty() ? ModifiedColumnSet.EMPTY
                                            : upstream.modifiedColumnSet();

                            final IterativeChunkedAggregationOperator.SingletonContext[] opContexts =
                                    new IterativeChunkedAggregationOperator.SingletonContext[ac.size()];
                            try (final SafeCloseable ignored = new SafeCloseableArray<>(opContexts)) {
                                final OperatorDivision od = new OperatorDivision(ac, upstream.modified().isNonempty(),
                                        upstreamModifiedColumnSet, inputModifiedColumnSet);
                                ac.initializeSingletonContexts(opContexts, upstream,
                                        od.operatorsWithModifiedInputColumns);

                                final boolean[] modifiedOperators = new boolean[ac.size()];
                                // remove all the removals
                                if (upstream.removed().isNonempty()) {
                                    doNoKeyRemoval(upstream.removed(), ac, opContexts, allColumns, modifiedOperators);
                                }

                                final boolean processShifts = upstream.shifted().nonempty() && ac.requiresIndices();

                                if (upstream.modified().isNonempty() && (od.anyOperatorHasModifiedInputColumns
                                        || od.anyOperatorWithoutModifiedInputColumnsRequiresIndices)) {
                                    if (processShifts) {
                                        // Also handles shifted modifications for modified-input operators that require
                                        // indices (if any)
                                        doNoKeyShifts(table, upstream, ac, opContexts, od.operatorsThatRequireIndices,
                                                modifiedOperators);

                                        try (final RowSet unshiftedModifies =
                                                extractUnshiftedModifiesFromUpstream(upstream)) {
                                            // Do unshifted modifies for everyone
                                            doNoKeyModifications(unshiftedModifies, unshiftedModifies, ac, opContexts,
                                                    true,
                                                    od.operatorsWithModifiedInputColumns,
                                                    od.operatorsWithoutModifiedInputColumnsThatRequireIndices,
                                                    modifiedOperators);

                                            if (od.anyOperatorWithModifiedInputColumnsIgnoresIndices) {
                                                // Do shifted modifies for RowSet-only and modified-input operators that
                                                // don't require indices
                                                try (final RowSet shiftedModifiesPost =
                                                        upstream.modified().minus(unshiftedModifies);
                                                        final WritableRowSet shiftedModifiesPre =
                                                                shiftedModifiesPost.copy()) {
                                                    upstream.shifted().unapply(shiftedModifiesPre);
                                                    doNoKeyModifications(shiftedModifiesPre, shiftedModifiesPost, ac,
                                                            opContexts, true,
                                                            od.operatorsWithModifiedInputColumnsThatIgnoreIndices,
                                                            od.operatorsThatRequireIndices,
                                                            modifiedOperators);
                                                }
                                            } else if (ac.requiresIndices()) {
                                                // Do shifted modifies for RowSet-only operators
                                                try (final RowSet shiftedModifiesPost =
                                                        upstream.modified().minus(unshiftedModifies)) {
                                                    doIndexOnlyNoKeyModifications(shiftedModifiesPost, ac, opContexts,
                                                            od.operatorsThatRequireIndices, modifiedOperators);
                                                }
                                            }
                                        }
                                    } else if (od.anyOperatorHasModifiedInputColumns) {
                                        doNoKeyModifications(upstream.getModifiedPreShift(), upstream.modified(), ac,
                                                opContexts, ac.requiresIndices(),
                                                od.operatorsWithModifiedInputColumns,
                                                od.operatorsWithoutModifiedInputColumnsThatRequireIndices,
                                                modifiedOperators);

                                    } else {
                                        doIndexOnlyNoKeyModifications(upstream.modified(), ac, opContexts,
                                                od.operatorsWithoutModifiedInputColumnsThatRequireIndices,
                                                modifiedOperators);
                                    }
                                } else if (processShifts) {
                                    doNoKeyShifts(table, upstream, ac, opContexts, od.operatorsThatRequireIndices,
                                            modifiedOperators);
                                }

                                if (upstream.added().isNonempty()) {
                                    doNoKeyAddition(upstream.added(), ac, opContexts, allColumns, false,
                                            modifiedOperators);
                                }

                                final int newResultSize =
                                        preserveEmpty || (isBlink && lastSize != 0) || table.size() != 0 ? 1 : 0;
                                final TableUpdateImpl downstream = new TableUpdateImpl();
                                downstream.shifted = RowSetShiftData.EMPTY;
                                if ((lastSize == 0 && newResultSize == 1)) {
                                    downstream.added = RowSetFactory.fromKeys(0);
                                    downstream.removed = RowSetFactory.empty();
                                    downstream.modified = RowSetFactory.empty();
                                    result.getRowSet().writableCast().insert(0);
                                } else if (lastSize == 1 && newResultSize == 0) {
                                    downstream.added = RowSetFactory.empty();
                                    downstream.removed = RowSetFactory.fromKeys(0);
                                    downstream.modified = RowSetFactory.empty();
                                    result.getRowSet().writableCast().remove(0);
                                } else if (anyTrue(BooleanChunk.chunkWrap(modifiedOperators))) {
                                    downstream.added = RowSetFactory.empty();
                                    downstream.removed = RowSetFactory.empty();
                                    downstream.modified = RowSetFactory.fromKeys(0);
                                } else {
                                    downstream.added = RowSetFactory.empty();
                                    downstream.removed = RowSetFactory.empty();
                                    downstream.modified = RowSetFactory.empty();
                                }
                                lastSize = newResultSize;

                                final int newStatesCreated = Math.max(statesCreated, newResultSize);
                                try (final RowSet newStates =
                                        makeNewStatesRowSet(statesCreated, newStatesCreated - 1)) {
                                    ac.propagateChangesToOperators(downstream, newStates);
                                }
                                statesCreated = newStatesCreated;

                                extractDownstreamModifiedColumnSet(downstream, result.getModifiedColumnSetForUpdates(),
                                        modifiedOperators, upstreamModifiedColumnSet, resultModifiedColumnSetFactories);

                                if (downstream.empty()) {
                                    downstream.release();
                                    return;
                                }

                                result.notifyListeners(downstream);
                            }
                        }

                        @Override
                        public void onFailureInternal(@NotNull final Throwable originalException,
                                final Entry sourceEntry) {
                            ac.propagateFailureToOperators(originalException, sourceEntry);
                            super.onFailureInternal(originalException, sourceEntry);
                        }
                    };
            snapshotControl.setListenerAndResult(listener, result);
        }

        ac.supplyRowLookup(() -> key -> Arrays.equals((Object[]) key, EMPTY_KEY) ? 0 : DEFAULT_UNKNOWN_ROW);

        final QueryTable finalResult = ac.transformResult(result);
        finalResult.setFlat();
        return finalResult;
    }

    private static void doNoKeyAddition(RowSequence index, AggregationContext ac,
            IterativeChunkedAggregationOperator.SingletonContext[] opContexts, boolean[] operatorsToProcess,
            boolean usePrev, boolean[] modifiedOperators) {
        doNoKeyUpdate(index, ac, opContexts, operatorsToProcess, usePrev, false, modifiedOperators);
    }

    private static void doNoKeyRemoval(RowSequence index, AggregationContext ac,
            IterativeChunkedAggregationOperator.SingletonContext[] opContexts, boolean[] operatorsToProcess,
            boolean[] modifiedOperators) {
        doNoKeyUpdate(index, ac, opContexts, operatorsToProcess, true, true, modifiedOperators);
    }

    private static void doNoKeyModifications(RowSequence preIndex, RowSequence postIndex, AggregationContext ac,
            IterativeChunkedAggregationOperator.SingletonContext[] opContexts,
            final boolean supplyPostIndices, @NotNull final boolean[] operatorsToProcess,
            @NotNull final boolean[] operatorsToProcessIndicesOnly, @NotNull final boolean[] modifiedOperators) {
        final ColumnSource.GetContext[] preGetContexts = new ColumnSource.GetContext[ac.size()];
        final ColumnSource.GetContext[] postGetContexts = new ColumnSource.GetContext[ac.size()];

        try (final SafeCloseableArray ignored = new SafeCloseableArray<>(preGetContexts);
                final SafeCloseableArray ignored2 = new SafeCloseableArray<>(postGetContexts);
                final SharedContext preSharedContext = SharedContext.makeSharedContext();
                final SharedContext postSharedContext = SharedContext.makeSharedContext();
                final RowSequence.Iterator preIt = preIndex.getRowSequenceIterator();
                final RowSequence.Iterator postIt = postIndex.getRowSequenceIterator()) {
            ac.initializeGetContexts(preSharedContext, preGetContexts, preIndex.size(), operatorsToProcess);
            ac.initializeGetContexts(postSharedContext, postGetContexts, postIndex.size(), operatorsToProcess);

            final Chunk[] workingPreChunks = new Chunk[ac.size()];
            final Chunk[] workingPostChunks = new Chunk[ac.size()];

            while (postIt.hasMore()) {
                final RowSequence postChunkOk = postIt.getNextRowSequenceWithLength(CHUNK_SIZE);
                final RowSequence preChunkOk = preIt.getNextRowSequenceWithLength(CHUNK_SIZE);

                final int chunkSize = postChunkOk.intSize();

                preSharedContext.reset();
                postSharedContext.reset();

                final LongChunk postKeyIndices =
                        supplyPostIndices ? postChunkOk.asRowKeyChunk() : null;

                Arrays.fill(workingPreChunks, null);
                Arrays.fill(workingPostChunks, null);

                for (int ii = 0; ii < ac.size(); ++ii) {
                    if (operatorsToProcessIndicesOnly[ii]) {
                        try {
                            modifiedOperators[ii] |= ac.operators[ii].modifyRowKeys(opContexts[ii], postKeyIndices, 0);
                        } catch (Exception ex) {
                            throw new AggregationOperatorException(
                                    "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[ii])
                                            + ", outputs=" + ac.operators[ii].getResultColumns().keySet(),
                                    ex);
                        } catch (Error err) {
                            err.addSuppressed(new AggregationOperatorException(
                                    "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[ii])
                                            + ", outputs=" + ac.operators[ii].getResultColumns().keySet()));
                            throw err;
                        }
                        continue;
                    }
                    if (operatorsToProcess[ii]) {
                        final Chunk preValues;
                        final Chunk postValues;
                        if (ac.inputColumns[ii] == null) {
                            preValues = postValues = null;
                        } else {
                            final int inputSlot = ac.inputSlot(ii);
                            if (workingPreChunks[inputSlot] == null) {
                                workingPreChunks[inputSlot] =
                                        ac.inputColumns[inputSlot].getPrevChunk(preGetContexts[inputSlot], preChunkOk);
                                workingPostChunks[inputSlot] =
                                        ac.inputColumns[inputSlot].getChunk(postGetContexts[inputSlot], postChunkOk);
                            }
                            preValues = workingPreChunks[inputSlot];
                            postValues = workingPostChunks[inputSlot];
                        }
                        try {
                            modifiedOperators[ii] |= ac.operators[ii].modifyChunk(opContexts[ii], chunkSize, preValues,
                                    postValues, postKeyIndices, 0);
                        } catch (Exception ex) {
                            throw new AggregationOperatorException(
                                    "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[ii])
                                            + ", outputs=" + ac.operators[ii].getResultColumns().keySet(),
                                    ex);
                        } catch (Error er) {
                            er.addSuppressed(new AggregationOperatorException(
                                    "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[ii])
                                            + ", outputs=" + ac.operators[ii].getResultColumns().keySet()));
                            throw er;
                        }
                    }
                }
            }
        }
    }

    private static void doIndexOnlyNoKeyModifications(@NotNull final RowSequence postIndex,
            @NotNull final AggregationContext ac,
            @NotNull final IterativeChunkedAggregationOperator.SingletonContext[] opContexts,
            @NotNull final boolean[] operatorsToProcessIndicesOnly, @NotNull final boolean[] modifiedOperators) {
        try (final RowSequence.Iterator postIt = postIndex.getRowSequenceIterator()) {
            while (postIt.hasMore()) {
                final RowSequence postChunkOk = postIt.getNextRowSequenceWithLength(CHUNK_SIZE);
                final LongChunk postKeyIndices = postChunkOk.asRowKeyChunk();
                for (int ii = 0; ii < ac.size(); ++ii) {
                    if (operatorsToProcessIndicesOnly[ii]) {
                        try {
                            modifiedOperators[ii] |= ac.operators[ii].modifyRowKeys(opContexts[ii], postKeyIndices, 0);
                        } catch (Exception ex) {
                            throw new AggregationOperatorException(
                                    "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[ii])
                                            + ", outputs=" + ac.operators[ii].getResultColumns().keySet(),
                                    ex);
                        } catch (Error err) {
                            err.addSuppressed(new AggregationOperatorException(
                                    "Failed to modify data, inputcolumns=" + Arrays.toString(ac.inputNames[ii])
                                            + ", outputs=" + ac.operators[ii].getResultColumns().keySet()));
                            throw err;
                        }
                    }
                }
            }
        }
    }

    private static void doNoKeyUpdate(RowSequence index, AggregationContext ac,
            IterativeChunkedAggregationOperator.SingletonContext[] opContexts,
            boolean[] operatorsToProcess, boolean usePrev, boolean remove, boolean[] modifiedOperators) {
        final ColumnSource.GetContext[] getContexts = new ColumnSource.GetContext[ac.size()];
        final boolean indicesRequired = ac.requiresIndices(operatorsToProcess);

        try (final SafeCloseableArray ignored = new SafeCloseableArray<>(getContexts);
                final SharedContext sharedContext = SharedContext.makeSharedContext();
                final RowSequence.Iterator rsIt = index.getRowSequenceIterator()) {
            ac.initializeGetContexts(sharedContext, getContexts, index.size(), operatorsToProcess);

            // noinspection unchecked
            final Chunk[] workingChunks = new Chunk[ac.size()];

            // on an empty initial pass we want to go through the operator anyway, so that we initialize things
            // correctly for the aggregation of zero keys
            do {
                final RowSequence chunkOk = rsIt.getNextRowSequenceWithLength(CHUNK_SIZE);
                sharedContext.reset();

                final LongChunk keyIndices = indicesRequired ? chunkOk.asRowKeyChunk() : null;

                Arrays.fill(workingChunks, null);

                for (int ii = 0; ii < ac.size(); ++ii) {
                    if (!operatorsToProcess[ii]) {
                        continue;
                    }
                    final int inputSlot = ac.inputSlot(ii);

                    if (inputSlot >= 0 && workingChunks[inputSlot] == null) {
                        workingChunks[inputSlot] =
                                fetchValues(usePrev, chunkOk, ac.inputColumns[inputSlot], getContexts[inputSlot]);
                    }

                    modifiedOperators[ii] |=
                            processColumnNoKey(remove, chunkOk, inputSlot >= 0 ? workingChunks[inputSlot] : null,
                                    ac.operators[ii], opContexts[ii], keyIndices, ac.inputNames[ii]);
                }
            } while (rsIt.hasMore());
        }
    }

    private static void doNoKeyShifts(QueryTable source, TableUpdate upstream, AggregationContext ac,
            final IterativeChunkedAggregationOperator.SingletonContext[] opContexts,
            boolean[] operatorsToShift, boolean[] modifiedOperators) {
        final ColumnSource.GetContext[] getContexts = new ColumnSource.GetContext[ac.size()];
        final ColumnSource.GetContext[] postGetContexts = new ColumnSource.GetContext[ac.size()];

        try (final RowSet useRowSet = source.getRowSet().minus(upstream.added())) {
            if (useRowSet.isEmpty()) {
                return;
            }
            final int chunkSize = chunkSize(useRowSet.size());
            try (final SafeCloseableArray ignored = new SafeCloseableArray<>(getContexts);
                    final SafeCloseableArray ignored2 = new SafeCloseableArray<>(postGetContexts);
                    final SharedContext sharedContext = SharedContext.makeSharedContext();
                    final SharedContext postSharedContext = SharedContext.makeSharedContext();
                    final WritableLongChunk preKeyIndices =
                            WritableLongChunk.makeWritableChunk(chunkSize);
                    final WritableLongChunk postKeyIndices =
                            WritableLongChunk.makeWritableChunk(chunkSize)) {
                ac.initializeGetContexts(sharedContext, getContexts, chunkSize, operatorsToShift);
                ac.initializeGetContexts(postSharedContext, postGetContexts, chunkSize, operatorsToShift);

                final Runnable applyChunkedShift =
                        () -> doProcessShiftNoKey(ac, opContexts, operatorsToShift, sharedContext, postSharedContext,
                                getContexts, postGetContexts, preKeyIndices, postKeyIndices, modifiedOperators);
                processUpstreamShifts(upstream, useRowSet, preKeyIndices, postKeyIndices, applyChunkedShift);
            }
        }
    }

    private static void doProcessShiftNoKey(AggregationContext ac,
            IterativeChunkedAggregationOperator.SingletonContext[] opContexts,
            boolean[] operatorsToShift, SharedContext sharedContext, SharedContext postSharedContext,
            ColumnSource.GetContext[] getContexts, ColumnSource.GetContext[] postGetContexts,
            WritableLongChunk preKeyIndices, WritableLongChunk postKeyIndices,
            boolean[] modifiedOperators) {
        // noinspection unchecked
        final Chunk[] workingPreChunks = new Chunk[ac.size()];
        // noinspection unchecked
        final Chunk[] workingPostChunks = new Chunk[ac.size()];

        try (final RowSequence preChunkOk = RowSequenceFactory.wrapRowKeysChunkAsRowSequence(preKeyIndices);
                final RowSequence postChunkOk = RowSequenceFactory.wrapRowKeysChunkAsRowSequence(postKeyIndices)) {
            sharedContext.reset();
            postSharedContext.reset();
            Arrays.fill(workingPreChunks, null);
            Arrays.fill(workingPostChunks, null);

            for (int ii = 0; ii < ac.size(); ++ii) {
                if (operatorsToShift[ii]) {
                    final Chunk previousValues;
                    final Chunk newValues;

                    final int inputSlot = ac.inputSlot(ii);
                    if (ac.inputColumns[ii] == null) {
                        previousValues = newValues = null;
                    } else {
                        if (workingPreChunks[inputSlot] == null) {
                            workingPreChunks[inputSlot] = ac.inputColumns[ii].getPrevChunk(getContexts[ii], preChunkOk);
                            workingPostChunks[inputSlot] =
                                    ac.inputColumns[ii].getChunk(postGetContexts[ii], postChunkOk);
                        }
                        previousValues = workingPreChunks[inputSlot];
                        newValues = workingPostChunks[inputSlot];
                    }

                    try {
                        modifiedOperators[ii] |= ac.operators[ii].shiftChunk(opContexts[ii], previousValues, newValues,
                                preKeyIndices, postKeyIndices, 0);
                    } catch (Exception ex) {
                        throw new AggregationOperatorException(
                                "Failed to shift data, inputcolumns=" + Arrays.toString(ac.inputNames[ii])
                                        + ", outputs=" + ac.operators[ii].getResultColumns().keySet(),
                                ex);
                    } catch (Error err) {
                        err.addSuppressed(new AggregationOperatorException(
                                "Failed to shift data, inputcolumns=" + Arrays.toString(ac.inputNames[ii])
                                        + ", outputs=" + ac.operators[ii].getResultColumns().keySet()));
                        throw err;
                    }
                }
            }
        }
    }

    private static boolean processColumnNoKey(boolean remove, RowSequence chunkOk, Chunk values,
            IterativeChunkedAggregationOperator operator,
            IterativeChunkedAggregationOperator.SingletonContext opContext,
            LongChunk keyIndices,
            String[] inputNames) {
        if (remove) {
            try {
                return operator.removeChunk(opContext, chunkOk.intSize(), values, keyIndices, 0);
            } catch (Exception ex) {
                throw new AggregationOperatorException("Failed to remove data, inputcolumns="
                        + Arrays.toString(inputNames) + ", outputs=" + operator.getResultColumns().keySet(), ex);
            } catch (Error err) {
                err.addSuppressed(new AggregationOperatorException("Failed to remove data, inputcolumns="
                        + Arrays.toString(inputNames) + ", outputs=" + operator.getResultColumns().keySet()));
                throw err;
            }
        } else {
            try {
                return operator.addChunk(opContext, chunkOk.intSize(), values, keyIndices, 0);
            } catch (Exception ex) {
                throw new AggregationOperatorException("Failed to add data, inputcolumns=" + Arrays.toString(inputNames)
                        + ", outputs=" + operator.getResultColumns().keySet(), ex);
            } catch (Error err) {
                err.addSuppressed(new AggregationOperatorException("Failed to add data, inputcolumns="
                        + Arrays.toString(inputNames) + ", outputs=" + operator.getResultColumns().keySet()));
                throw err;
            }
        }
    }

    @Nullable
    private static Chunk fetchValues(boolean usePrev, RowSequence chunkOk,
            ChunkSource.WithPrev inputColumn, ChunkSource.GetContext getContext) {
        final Chunk values;
        if (inputColumn == null) {
            values = null;
        } else if (usePrev) {
            // noinspection unchecked
            values = inputColumn.getPrevChunk(getContext, chunkOk);
        } else {
            // noinspection unchecked
            values = inputColumn.getChunk(getContext, chunkOk);
        }
        return values;
    }

    /**
     * Return the minimum of our chunk size and the size of an input.
     *
     * @param size the input size
     * @return an appropriate chunk size to use
     */
    public static int chunkSize(long size) {
        return (int) Math.min(size, CHUNK_SIZE);
    }

    /**
     * {@link RowSetBuilderRandom} that ignores added keys and always {@link RowSetBuilderRandom#build() builds} an
     * {@link RowSetFactory#empty() empty} result.
     */
    private static class EmptyRandomBuilder implements RowSetBuilderRandom {

        @Override
        public WritableRowSet build() {
            return RowSetFactory.empty();
        }

        @Override
        public void addKey(long rowKey) {
            // This class expects to never process any adds.
            throw new UnsupportedOperationException();
        }

        @Override
        public void addRange(final long firstRowKey, final long lastRowKey) {
            // This class expects to never process any adds.
            throw new UnsupportedOperationException();
        }
    }

}