/*
    * 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.
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  package org.apache.giraph.examples;
  
  import org.apache.giraph.combiner.DoubleSumMessageCombiner;
  import org.apache.giraph.conf.GiraphConfiguration;
  import org.apache.giraph.edge.LongNullArrayEdges;
  import org.apache.giraph.utils.InternalVertexRunner;
  import org.junit.Test;
  
  import java.util.Map;
  
  import static org.junit.Assert.assertEquals;
  
  
  /**
   * Tests for {@link PageRankComputation}
   */
  public class PageRankComputationTest {
  
    /**
     * A local integration test on toy data
     */
    @Test
    public void testToyData() throws Exception {
  
      // A small graph
      String[] graph = new String[] {
        "1 4 2 3",
        "2 1",
        "4 3 2",
        "5 2 4"
      };
  
      GiraphConfiguration conf = new GiraphConfiguration();
      conf.setInt(RandomWalkWithRestartComputation.MAX_SUPERSTEPS, 50);
      conf.setFloat(
          RandomWalkWithRestartComputation.TELEPORTATION_PROBABILITY, 0.15f);
      conf.setComputationClass(PageRankComputation.class);
      conf.setMessageCombinerClass(DoubleSumMessageCombiner.class);
      conf.setOutEdgesClass(LongNullArrayEdges.class);
      conf.setVertexInputFormatClass(LongDoubleNullTextInputFormat.class);
      conf.setVertexOutputFormatClass(
          VertexWithDoubleValueNullEdgeTextOutputFormat.class);
      conf.setWorkerContextClass(RandomWalkWorkerContext.class);
      conf.setMasterComputeClass(RandomWalkVertexMasterCompute.class);
      // Run internally
      Iterable<String> results = InternalVertexRunner.run(conf, graph);
  
      Map<Long, Double> steadyStateProbabilities =
          RandomWalkTestUtils.parseSteadyStateProbabilities(results);
  
      assertEquals(0.28159076008518047, steadyStateProbabilities.get(1l),
          RandomWalkTestUtils.EPSILON);
      assertEquals(0.2514648601529863, steadyStateProbabilities.get(2l),
          RandomWalkTestUtils.EPSILON);
      assertEquals(0.22262961972286327, steadyStateProbabilities.get(3l),
          RandomWalkTestUtils.EPSILON);
      assertEquals(0.17646783276703806, steadyStateProbabilities.get(4l),
          RandomWalkTestUtils.EPSILON);
      assertEquals(0.06784692727193153, steadyStateProbabilities.get(5l),
          RandomWalkTestUtils.EPSILON);
    }
  
  }