/*
    * 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.bsp.CentralizedServiceWorker;
  import org.apache.giraph.conf.ImmutableClassesGiraphConfiguration;
  import org.apache.giraph.edge.Edge;
  import org.apache.giraph.utils.ByteArrayVertexIdEdges;
  import org.apache.giraph.utils.PairList;
  import org.apache.giraph.utils.VertexIdEdges;
  import org.apache.giraph.worker.WorkerInfo;
  import org.apache.hadoop.io.Writable;
  import org.apache.hadoop.io.WritableComparable;
  
  import static org.apache.giraph.conf.GiraphConstants.ADDITIONAL_EDGE_REQUEST_SIZE;
  import static org.apache.giraph.conf.GiraphConstants.MAX_EDGE_REQUEST_SIZE;
  
  /**
   * Aggregates the edges to be sent to workers so they can be sent
   * in bulk.  Not thread-safe.
   *
   * @param <I> Vertex id
   * @param <E> Edge value
   */
  public class SendEdgeCache<I extends WritableComparable, E extends Writable>
      extends SendVertexIdDataCache<I, Edge<I, E>, VertexIdEdges<I, E>> {
    /**
     * Constructor
     *
     * @param conf Giraph configuration
     * @param serviceWorker Service worker
     */
    public SendEdgeCache(ImmutableClassesGiraphConfiguration conf,
                         CentralizedServiceWorker<?, ?, ?> serviceWorker) {
      super(conf, serviceWorker, MAX_EDGE_REQUEST_SIZE.get(conf),
          ADDITIONAL_EDGE_REQUEST_SIZE.get(conf));
    }
  
    @Override
    public VertexIdEdges<I, E> createVertexIdData() {
      return new ByteArrayVertexIdEdges<I, E>();
    }
  
    /**
     * Add an edge to the cache.
     *
     * @param workerInfo the remote worker destination
     * @param partitionId the remote Partition this edge belongs to
     * @param destVertexId vertex id that is ultimate destination
     * @param edge Edge to send to remote worker
     * @return Size of edges for the worker.
     */
    public int addEdge(WorkerInfo workerInfo,
                       int partitionId, I destVertexId, Edge<I, E> edge) {
      return addData(workerInfo, partitionId, destVertexId, edge);
    }
  
    /**
     * Gets the edges for a worker and removes it from the cache.
     *
     * @param workerInfo the address of the worker who owns the data
     *                   partitions that are receiving the edges
     * @return List of pairs (partitionId, ByteArrayVertexIdEdges),
     *         where all partition ids belong to workerInfo
     */
    public PairList<Integer, VertexIdEdges<I, E>>
    removeWorkerEdges(WorkerInfo workerInfo) {
      return removeWorkerData(workerInfo);
    }
  
    /**
     * Gets all the edges and removes them from the cache.
     *
     * @return All vertex edges for all partitions
     */
    public PairList<WorkerInfo, PairList<Integer, VertexIdEdges<I, E>>>
    removeAllEdges() {
      return removeAllData();
    }
  }