/*

  * 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 it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;

 import java.io.DataInput;

 import java.io.DataOutput;

 import java.io.IOException;

 import java.util.Map.Entry;

 import org.apache.giraph.bsp.CentralizedServiceWorker;

 import org.apache.giraph.comm.ServerData;

 import org.apache.giraph.comm.messages.MessageStore;

 import org.apache.giraph.conf.ImmutableClassesGiraphConfiguration;

 import org.apache.giraph.partition.PartitionOwner;

 import org.apache.giraph.utils.ByteArrayOneMessageToManyIds;

 import org.apache.giraph.utils.ByteArrayVertexIdMessages;

 import org.apache.giraph.utils.VertexIdMessageIterator;

 import org.apache.hadoop.io.Writable;

 import org.apache.hadoop.io.WritableComparable;

 /**

  * Send a collection of ByteArrayOneMessageToManyIds messages to a worker.

  *

  * @param <I> Vertex id

  * @param <M> Message data

  */

 @SuppressWarnings("unchecked")

 public class SendWorkerOneMessageToManyRequest<I extends WritableComparable,

     M extends Writable> extends WritableRequest<I, Writable, Writable>

     implements WorkerRequest<I, Writable, Writable> {

   /** ByteArrayOneMessageToManyIds encoding of vertexId & messages */

   protected ByteArrayOneMessageToManyIds<I, M> oneMessageToManyIds;

   /**

    * Constructor used for reflection only.

    */

   public SendWorkerOneMessageToManyRequest() { }

   /**

    * Constructor used to send request.

    *

    * @param oneMessageToManyIds ByteArrayOneMessageToManyIds

    * @param conf ImmutableClassesGiraphConfiguration

    */

   public SendWorkerOneMessageToManyRequest(

       ByteArrayOneMessageToManyIds<I, M> oneMessageToManyIds,

       ImmutableClassesGiraphConfiguration conf) {

     this.oneMessageToManyIds = oneMessageToManyIds;

     setConf(conf);

   }

   @Override

   public RequestType getType() {

     return RequestType.SEND_WORKER_ONE_MESSAGE_TO_MANY_REQUEST;

   }

   @Override

   public void readFieldsRequest(DataInput input) throws IOException {

     oneMessageToManyIds = new ByteArrayOneMessageToManyIds<>(

         getConf().<M>createOutgoingMessageValueFactory());

     oneMessageToManyIds.setConf(getConf());

     oneMessageToManyIds.readFields(input);

   }

   @Override

   public void writeRequest(DataOutput output) throws IOException {

     this.oneMessageToManyIds.write(output);

   }

   @Override

   public int getSerializedSize() {

     return super.getSerializedSize() +

         this.oneMessageToManyIds.getSerializedSize();

   }

   @Override

   public void doRequest(ServerData serverData) {

     MessageStore<I, M> messageStore = serverData.getIncomingMessageStore();

     if (messageStore.isPointerListEncoding()) {

       // if message store is pointer list based then send data as is

       messageStore.addPartitionMessages(-1, oneMessageToManyIds);

     } else { // else split the data per partition and send individually

       CentralizedServiceWorker<I, ?, ?> serviceWorker =

           serverData.getServiceWorker();

       // Get the initial size of ByteArrayVertexIdMessages per partition

       // on this worker. To make sure every ByteArrayVertexIdMessages to have

       // enough space to store the messages, we divide the original

       // ByteArrayOneMessageToManyIds message size by the number of partitions

       // and double the size

       // (Assume the major component in ByteArrayOneMessageToManyIds message

       // is a id list. Now each target id has a copy of message,

       // therefore we double the buffer size)

       // to get the initial size of ByteArrayVertexIdMessages.

       int initialSize = oneMessageToManyIds.getSize() /

           serverData.getPartitionStore().getNumPartitions() * 2;

       // Create ByteArrayVertexIdMessages for

       // message reformatting.

       Int2ObjectOpenHashMap<ByteArrayVertexIdMessages> partitionIdMsgs =

           new Int2ObjectOpenHashMap<>();

       // Put data from ByteArrayOneMessageToManyIds

       // to ByteArrayVertexIdMessages

       VertexIdMessageIterator<I, M> vertexIdMessageIterator =

         oneMessageToManyIds.getVertexIdMessageIterator();

       while (vertexIdMessageIterator.hasNext()) {

         vertexIdMessageIterator.next();

         M msg = vertexIdMessageIterator.getCurrentMessage();

         I vertexId = vertexIdMessageIterator.getCurrentVertexId();

         PartitionOwner owner =

             serviceWorker.getVertexPartitionOwner(vertexId);

         int partitionId = owner.getPartitionId();

         ByteArrayVertexIdMessages<I, M> idMsgs = partitionIdMsgs

             .get(partitionId);

         if (idMsgs == null) {

           idMsgs = new ByteArrayVertexIdMessages<>(

               getConf().<M>createOutgoingMessageValueFactory());

           idMsgs.setConf(getConf());

           idMsgs.initialize(initialSize);

           partitionIdMsgs.put(partitionId, idMsgs);

         }

         idMsgs.add(vertexId, msg);

       }

       // Read ByteArrayVertexIdMessages and write to message store

       for (Entry<Integer, ByteArrayVertexIdMessages> idMsgs :

           partitionIdMsgs.entrySet()) {

         if (!idMsgs.getValue().isEmpty()) {

           serverData.getIncomingMessageStore().addPartitionMessages(

               idMsgs.getKey(), idMsgs.getValue());

         }

       }

     }

   }

 }