/*
    * 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.examples;
  
  import org.apache.giraph.BspCase;
  import org.apache.giraph.conf.GiraphConfiguration;
  import org.apache.giraph.conf.GiraphConstants;
  import org.apache.giraph.job.GiraphJob;
  import org.junit.Test;
  
  import java.io.IOException;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertTrue;
  
  /**
   * Test page rank (with and without multithreading)
   */
  public class TestPageRank extends BspCase {
  
    /**
     * Constructor
     */
    public TestPageRank() {
      super(TestPageRank.class.getName());
    }
  
    @Test
    public void testBspPageRankSingleCompute()
        throws ClassNotFoundException, IOException, InterruptedException {
      testPageRank(1);
    }
  
  
    @Test
    public void testPageRankTenThreadsCompute()
        throws ClassNotFoundException, IOException, InterruptedException {
      testPageRank(10);
    }
  
    /**
     * Generic page rank test
     *
     * @param numComputeThreads Number of compute threads to use
     * @throws java.io.IOException
     * @throws ClassNotFoundException
     * @throws InterruptedException
     */
    private void testPageRank(int numComputeThreads)
        throws IOException, InterruptedException, ClassNotFoundException {
      GiraphConfiguration conf = new GiraphConfiguration();
      conf.setComputationClass(SimplePageRankComputation.class);
      conf.setVertexInputFormatClass(
          SimplePageRankComputation.SimplePageRankVertexInputFormat.class);
      conf.setWorkerContextClass(
          SimplePageRankComputation.SimplePageRankWorkerContext.class);
      conf.setMasterComputeClass(
          SimplePageRankComputation.SimplePageRankMasterCompute.class);
      conf.setNumComputeThreads(numComputeThreads);
      // Set enough partitions to generate randomness on the compute side
      if (numComputeThreads != 1) {
        GiraphConstants.USER_PARTITION_COUNT.set(conf, numComputeThreads * 5);
      }
      GiraphJob job = prepareJob(getCallingMethodName(), conf);
      assertTrue(job.run(true));
      if (!runningInDistributedMode()) {
        double maxPageRank =
            SimplePageRankComputation.SimplePageRankWorkerContext.getFinalMax();
        double minPageRank =
            SimplePageRankComputation.SimplePageRankWorkerContext.getFinalMin();
        long numVertices =
            SimplePageRankComputation.SimplePageRankWorkerContext.getFinalSum();
        System.out.println(getCallingMethodName() + ": maxPageRank=" +
            maxPageRank + " minPageRank=" +
            minPageRank + " numVertices=" + numVertices + ", " +
            " numComputeThreads=" + numComputeThreads);
        assertEquals(34.03, maxPageRank, 0.001);
        assertEquals(0.03, minPageRank, 0.00001);
        assertEquals(5L, numVertices);
      }
    }
  }