content: /*
   * Copyright (C) 2020 ActiveJ LLC.
   *
   * Licensed 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 io.activej.dataflow.dataset.impl;
  
  import io.activej.common.annotation.ExposedInternals;
  import io.activej.dataflow.dataset.Dataset;
  import io.activej.dataflow.dataset.LocallySortedDataset;
  import io.activej.dataflow.graph.DataflowContext;
  import io.activej.dataflow.graph.Partition;
  import io.activej.dataflow.graph.StreamId;
  import io.activej.dataflow.graph.StreamSchema;
  import io.activej.datastream.processor.reducer.Reducer;
  
  import java.util.Collection;
  import java.util.List;
  
  import static io.activej.dataflow.dataset.DatasetUtils.repartitionAndReduce;
  
  @ExposedInternals
  public final class RepartitionReduce<K, I, O> extends Dataset<O> {
  	public final LocallySortedDataset<K, I> input;
  	public final Reducer<K, I, O, ?> reducer;
  	public final List<Partition> partitions;
  
  	public RepartitionReduce(
  		LocallySortedDataset<K, I> input, Reducer<K, I, O, ?> reducer, StreamSchema<O> resultStreamSchema,
  		List<Partition> partitions
  	) {
  		super(resultStreamSchema);
  		this.input = input;
  		this.reducer = reducer;
  		this.partitions = partitions;
  	}
  
  	@Override
  	public List<StreamId> channels(DataflowContext context) {
  		List<Partition> ps = partitions != null && !partitions.isEmpty() ?
  			partitions :
  			context.getGraph().getAvailablePartitions();
  		return repartitionAndReduce(context, input, reducer, ps);
  	}
  
  	@Override
  	public Collection<Dataset<?>> getBases() {
  		return List.of(input);
  	}
  }
  