/*

  * 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;

 import org.apache.giraph.comm.RequestRegistry.Type;

 import org.apache.giraph.graph.BspUtils;

 import org.apache.hadoop.io.Writable;

 import org.apache.hadoop.io.WritableComparable;

 import org.apache.log4j.Logger;

 import com.google.common.collect.Lists;

 import com.google.common.collect.Maps;

 import java.io.DataInput;

 import java.io.DataOutput;

 import java.io.IOException;

 import java.util.Collection;

 import java.util.List;

 import java.util.Map;

 import java.util.Map.Entry;

 /**

  * Send a collection of vertex messages for a partition.

  *

  * @param <I> Vertex id

  * @param <V> Vertex data

  * @param <E> Edge data

  * @param <M> Message data

  */

 @SuppressWarnings("rawtypes")

 public class SendPartitionMessagesRequest<I extends WritableComparable,

     V extends Writable, E extends Writable,

     M extends Writable> extends WritableRequest<I, V, E, M> {

   /** Class logger */

   private static final Logger LOG =

       Logger.getLogger(SendPartitionMessagesRequest.class);

   /** Partition id */

   private int partitionId;

   /** Messages sent for a partition */

   private Map<I, Collection<M>> vertexIdMessages;

   /**

    * Constructor used for reflection only

    */

   public SendPartitionMessagesRequest() { }

   /**

    * Constructor used to send request.

    *

    * @param partitionId Partition to send the request to

    * @param vertexIdMessages Map of messages to send

    */

   public SendPartitionMessagesRequest(int partitionId,

                                       Map<I, Collection<M>> vertexIdMessages) {

     this.partitionId = partitionId;

     this.vertexIdMessages = vertexIdMessages;

   }

   @Override

   public void readFieldsRequest(DataInput input) throws IOException {

     partitionId = input.readInt();

     int vertexIdMessagesSize = input.readInt();

     vertexIdMessages = Maps.newHashMapWithExpectedSize(vertexIdMessagesSize);

     for (int i = 0; i < vertexIdMessagesSize; ++i) {

       I vertexId = BspUtils.<I>createVertexId(getConf());

       vertexId.readFields(input);

       int messageCount = input.readInt();

       List<M> messageList = Lists.newArrayListWithCapacity(messageCount);

       for (int j = 0; j < messageCount; ++j) {

         M message = BspUtils.<M>createMessageValue(getConf());

         message.readFields(input);

         messageList.add(message);

       }

       if (vertexIdMessages.put(vertexId, messageList) != null) {

         throw new IllegalStateException(

             "readFields: Already has vertex id " + vertexId);

       }

     }

   }

   @Override

   public void writeRequest(DataOutput output) throws IOException {

     output.writeInt(partitionId);

     output.writeInt(vertexIdMessages.size());

     for (Entry<I, Collection<M>> entry : vertexIdMessages.entrySet()) {

       entry.getKey().write(output);

       output.writeInt(entry.getValue().size());

       for (M message : entry.getValue()) {

         message.write(output);

       }

     }

   }

   @Override

   public Type getType() {

     return Type.SEND_PARTITION_MESSAGES_REQUEST;

   }

   @Override

   public void doRequest(ServerData<I, V, E, M> serverData) {

     try {

       serverData.getIncomingMessageStore().addPartitionMessages(

           vertexIdMessages, partitionId);

     } catch (IOException e) {

       throw new RuntimeException("doRequest: Got IOException ", e);

     }

   }

   /**

    * Get id of partition

    *

    * @return Partition id

    */

   public int getPartitionId() {

     return partitionId;

   }

   /**

    * Get messages

    *

    * @return Messages map

    */

   public Map<I, Collection<M>> getVertexIdMessages() {

     return vertexIdMessages;

   }

 }