/*
 * 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.giraph.comm.requests;

import org.apache.giraph.master.MasterGlobalCommHandler;
import org.apache.giraph.partition.PartitionStats;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * Request for sending partition stats from workers to master
 */
public class PartitionStatsRequest extends WritableRequest
    implements MasterRequest {
  /** Partition stats */
  private List<PartitionStats> partitionStats;

  /**
   * Constructor
   *
   * @param partitionStats Partition stats to send
   */
  public PartitionStatsRequest(Collection<PartitionStats> partitionStats) {
    this.partitionStats = new ArrayList<>(partitionStats);
  }

  /** Constructor for reflection */
  public PartitionStatsRequest() {
  }

  @Override
  public void doRequest(MasterGlobalCommHandler commHandler) {
    commHandler.receivedPartitionStats(partitionStats);
  }

  @Override
  public RequestType getType() {
    return RequestType.PARTITION_STATS_REQUEST;
  }

  @Override
  void writeRequest(DataOutput output) throws IOException {
    output.writeInt(partitionStats.size());
    for (PartitionStats partitionStat : partitionStats) {
      partitionStat.write(output);
    }
  }

  @Override
  void readFieldsRequest(DataInput input) throws IOException {
    int size = input.readInt();
    partitionStats = new ArrayList<>(size);
    for (int i = 0; i < size; i++) {
      PartitionStats newPartitionStats = new PartitionStats();
      newPartitionStats.readFields(input);
      partitionStats.add(newPartitionStats);
    }
  }
}
