/*

  * 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.block_app.framework.piece.delegate;

 import java.util.ArrayList;

 import org.apache.giraph.block_app.framework.api.BlockWorkerReceiveApi;

 import org.apache.giraph.block_app.framework.api.BlockWorkerSendApi;

 import org.apache.giraph.block_app.framework.piece.AbstractPiece;

 import org.apache.giraph.block_app.framework.piece.interfaces.VertexReceiver;

 import org.apache.giraph.function.vertex.SupplierFromVertex;

 import org.apache.giraph.graph.Vertex;

 import org.apache.hadoop.io.Writable;

 import org.apache.hadoop.io.WritableComparable;

 import com.google.common.base.Preconditions;

 /**

  * Piece which uses a provided suppliers to decide whether or not to run

  * receive/send piece part on a certain vertex.

  *

  * @param <I> Vertex id type

  * @param <V> Vertex value type

  * @param <E> Edge value type

  * @param <M> Message type

  * @param <WV> Worker value type

  * @param <WM> Worker message type

  * @param <S> Execution stage type

  */

 @SuppressWarnings({ "rawtypes" })

 public class FilteringPiece<I extends WritableComparable, V extends Writable,

     E extends Writable, M extends Writable, WV, WM extends Writable, S>

     extends DelegatePiece<I, V, E, M, WV, WM, S> {

   private final SupplierFromVertex<I, V, E, Boolean> toCallSend;

   private final SupplierFromVertex<I, V, E, Boolean> toCallReceive;

   /**

    * Creates filtering piece which uses passed {@code toCallSend} to filter

    * calls to {@code vertexSend}, and passed {@code toCallReceive} to filter

    * calls to {@code vertexReceive}, on passed {@code innerPiece}.

    */

   @SuppressWarnings("unchecked")

   public FilteringPiece(

       SupplierFromVertex<? super I, ? super V, ? super E, Boolean> toCallSend,

       SupplierFromVertex<? super I, ? super V, ? super E, Boolean>

         toCallReceive,

       AbstractPiece<? super I, ? super V, ? super E, ? super M,

         ? super WV, ? super WM, ? super S> innerPiece) {

     super(innerPiece);

     // Suppliers are contravariant on vertex types,

     // but Java generics cannot express that,

     // so use unchecked cast inside to allow callers to be typesafe

     this.toCallSend = (SupplierFromVertex) toCallSend;

     this.toCallReceive = (SupplierFromVertex) toCallReceive;

     Preconditions.checkArgument(

         toCallSend != null || toCallReceive != null,

         "Both send and receive filter cannot be null");

   }

   /**

    * Creates filtering piece, where both vertexSend and vertexReceive is

    * filtered based on same supplier.

    */

   public FilteringPiece(

       SupplierFromVertex<? super I, ? super V, ? super E, Boolean>

         toCallSendAndReceive,

       AbstractPiece<? super I, ? super V, ? super E, ? super M,

         ? super WV, ? super WM, ? super S> innerPiece) {

     this(toCallSendAndReceive, toCallSendAndReceive, innerPiece);

   }

   /**

    * Creates filtering piece, that filters only vertexReceive function,

    * and always calls vertexSend function.

    */

   public static <I extends WritableComparable, V extends Writable,

   E extends Writable, M extends Writable, WV, WM extends Writable, S>

   FilteringPiece<I, V, E, M, WV, WM, S> createReceiveFiltering(

       SupplierFromVertex<? super I, ? super V, ? super E, Boolean>

         toCallReceive,

       AbstractPiece<? super I, ? super V, ? super E, ? super M,

         ? super WV, ? super WM, ? super S> innerPiece) {

     return new FilteringPiece<>(null, toCallReceive, innerPiece);

   }

   /**

    * Creates filtering block, that filters only vertexSend function,

    * and always calls vertexReceive function.

    */

   public static <I extends WritableComparable, V extends Writable,

   E extends Writable, M extends Writable, WV, WM extends Writable, S>

   FilteringPiece<I, V, E, M, WV, WM, S> createSendFiltering(

       SupplierFromVertex<? super I, ? super V, ? super E, Boolean> toCallSend,

       AbstractPiece<? super I, ? super V, ? super E, ? super M, ? super WV,

         ? super WM, ? super S> innerPiece) {

     return new FilteringPiece<>(toCallSend, null, innerPiece);

   }

   @Override

   protected DelegateWorkerSendFunctions delegateWorkerSendFunctions(

       ArrayList<InnerVertexSender> workerSendFunctions,

       BlockWorkerSendApi<I, V, E, M> workerApi, S executionStage) {

     return new DelegateWorkerSendFunctions(workerSendFunctions) {

       @Override

       public void vertexSend(Vertex<I, V, E> vertex) {

         if (toCallSend == null || toCallSend.get(vertex)) {

           super.vertexSend(vertex);

         }

       }

     };

   }

   @Override

   protected DelegateWorkerReceiveFunctions delegateWorkerReceiveFunctions(

       ArrayList<VertexReceiver<I, V, E, M>> workerReceiveFunctions,

       BlockWorkerReceiveApi<I> workerApi, S executionStage) {

     return new DelegateWorkerReceiveFunctions(workerReceiveFunctions) {

       @Override

       public void vertexReceive(Vertex<I, V, E> vertex, Iterable<M> messages) {

         if (toCallReceive == null || toCallReceive.get(vertex)) {

           super.vertexReceive(vertex, messages);

         }

       }

     };

   }

   @Override

   protected String delegationName() {

     if (toCallSend != null && toCallReceive != null) {

       if (toCallSend != toCallReceive) {

         return "AsymFilter";

       }

       return "Filter";

     } else if (toCallSend != null) {

       return "SendFilter";

     } else if (toCallReceive != null) {

       return "ReceiveFilter";

     } else {

       throw new IllegalStateException("Both Send and Receive filters are null");

     }

   }

 }