content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements. See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License. You may obtain a copy of the License at
   *
   *    http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.kafka.streams.kstream.internals;
  
  import org.apache.kafka.common.serialization.Serde;
  import org.apache.kafka.streams.kstream.Aggregator;
  import org.apache.kafka.streams.kstream.Initializer;
  import org.apache.kafka.streams.kstream.KTable;
  import org.apache.kafka.streams.kstream.internals.graph.GracePeriodGraphNode;
  import org.apache.kafka.streams.kstream.internals.graph.GraphNode;
  import org.apache.kafka.streams.kstream.internals.graph.ProcessorGraphNode;
  import org.apache.kafka.streams.kstream.internals.graph.ProcessorParameters;
  
  import java.util.Collections;
  import java.util.Set;
  
  import static org.apache.kafka.streams.kstream.internals.graph.OptimizableRepartitionNode.OptimizableRepartitionNodeBuilder;
  import static org.apache.kafka.streams.kstream.internals.graph.OptimizableRepartitionNode.optimizableRepartitionNodeBuilder;
  
  class GroupedStreamAggregateBuilder<K, V> {
  
      private final InternalStreamsBuilder builder;
      private final Serde<K> keySerde;
      private final Serde<V> valueSerde;
      private final boolean repartitionRequired;
      private final String userProvidedRepartitionTopicName;
      private final Set<String> subTopologySourceNodes;
      private final String name;
      private final GraphNode graphNode;
      private GraphNode repartitionNode;
  
      final Initializer<Long> countInitializer = () -> 0L;
  
      final Aggregator<K, V, Long> countAggregator = (aggKey, value, aggregate) -> aggregate + 1;
  
      final Initializer<V> reduceInitializer = () -> null;
  
      GroupedStreamAggregateBuilder(final InternalStreamsBuilder builder,
                                    final GroupedInternal<K, V> groupedInternal,
                                    final boolean repartitionRequired,
                                    final Set<String> subTopologySourceNodes,
                                    final String name,
                                    final GraphNode graphNode) {
  
          this.builder = builder;
          this.keySerde = groupedInternal.keySerde();
          this.valueSerde = groupedInternal.valueSerde();
          this.repartitionRequired = repartitionRequired;
          this.subTopologySourceNodes = subTopologySourceNodes;
          this.name = name;
          this.graphNode = graphNode;
          this.userProvidedRepartitionTopicName = groupedInternal.name();
      }
  
      <KR, VR> KTable<KR, VR> buildNonWindowed(final NamedInternal functionName,
                                               final String storeName,
                                               final KStreamAggProcessorSupplier<K, V, KR, VR> aggregateSupplier,
                                               final String queryableStoreName,
                                               final Serde<KR> keySerde,
                                               final Serde<VR> valueSerde,
                                               final boolean isOutputVersioned) {
          final String aggFunctionName = functionName.name();
  
          final ProcessorGraphNode<K, V> aggProcessorNode =
              new ProcessorGraphNode<>(
                  aggFunctionName,
                  new ProcessorParameters<>(aggregateSupplier, aggFunctionName)
              );
  
          aggProcessorNode.setOutputVersioned(isOutputVersioned);
  
          return build(aggFunctionName, storeName, aggregateSupplier, aggProcessorNode, queryableStoreName, keySerde, valueSerde);
      }
  
      <KR, VR> KTable<KR, VR> buildWindowed(final NamedInternal functionName,
                                            final String storeName,
                                            final long gracePeriod,
                                            final KStreamAggProcessorSupplier<K, V, KR, VR> aggregateSupplier,
                                            final String queryableStoreName,
                                            final Serde<KR> keySerde,
                                            final Serde<VR> valueSerde,
                                            final boolean isOutputVersioned) {
          final String aggFunctionName = functionName.name();
  
          final GracePeriodGraphNode<K, V> gracePeriodAggProcessorNode =
              new GracePeriodGraphNode<>(
                  aggFunctionName,
                  new ProcessorParameters<>(aggregateSupplier, aggFunctionName),
                  gracePeriod
              );
  
          gracePeriodAggProcessorNode.setOutputVersioned(isOutputVersioned);
  
          return build(aggFunctionName, storeName, aggregateSupplier, gracePeriodAggProcessorNode, queryableStoreName, keySerde, valueSerde);
      }
  
      private <KR, VR> KTable<KR, VR> build(final String aggFunctionName,
                                            final String storeName,
                                            final KStreamAggProcessorSupplier<K, V, KR, VR> aggregateSupplier,
                                            final ProcessorGraphNode<K, V> aggProcessorNode,
                                            final String queryableStoreName,
                                            final Serde<KR> keySerde,
                                            final Serde<VR> valueSerde) {
          if (!(queryableStoreName == null || queryableStoreName.equals(storeName))) {
              throw new IllegalStateException(String.format("queryableStoreName should be null or equal to storeName"
                                                                + " but got storeName='%s' and queryableStoreName='%s'",
                                                            storeName, queryableStoreName));
          }
  
          String sourceName = this.name;
          GraphNode parentNode = graphNode;
  
          if (repartitionRequired) {
              final OptimizableRepartitionNodeBuilder<K, V> repartitionNodeBuilder = optimizableRepartitionNodeBuilder();
  
              final String repartitionTopicPrefix = userProvidedRepartitionTopicName != null ? userProvidedRepartitionTopicName : storeName;
  
              sourceName = createRepartitionSource(repartitionTopicPrefix, repartitionNodeBuilder, userProvidedRepartitionTopicName != null || queryableStoreName != null);
  
              // First time through we need to create a repartition node.
              // Any subsequent calls to GroupedStreamAggregateBuilder#build we check if
              // the user has provided a name for the repartition topic, is so we re-use
              // the existing repartition node, otherwise we create a new one.
              if (repartitionNode == null || userProvidedRepartitionTopicName == null) {
                  repartitionNode = repartitionNodeBuilder.build();
              }
  
              builder.addGraphNode(parentNode, repartitionNode);
              parentNode = repartitionNode;
          }
  
          builder.addGraphNode(parentNode, aggProcessorNode);
  
          return new KTableImpl<>(aggFunctionName,
                                  keySerde,
                                  valueSerde,
                                  sourceName.equals(this.name) ? subTopologySourceNodes : Collections.singleton(sourceName),
                                  queryableStoreName,
                                  aggregateSupplier,
                                  aggProcessorNode,
                                  builder);
      }
  
      /**
       * @return the new sourceName of the repartitioned source
       */
      private String createRepartitionSource(final String repartitionTopicNamePrefix,
                                             final OptimizableRepartitionNodeBuilder<K, V> optimizableRepartitionNodeBuilder,
                                             final boolean isRepartitionTopicNameProvidedByUser) {
  
          return KStreamImpl.createRepartitionedSource(builder,
                                                       keySerde,
                                                       valueSerde,
                                                       repartitionTopicNamePrefix,
                                                       null,
                                                       optimizableRepartitionNodeBuilder,
                                                       isRepartitionTopicNameProvidedByUser);
  
      }
  }
  