/*
    * 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.commons.math4.legacy.genetics;
  
  import java.util.Arrays;
  import java.util.HashSet;
  import java.util.Set;
  
  import org.apache.commons.math4.legacy.exception.DimensionMismatchException;
  import org.apache.commons.math4.legacy.exception.MathIllegalArgumentException;
  import org.junit.Assert;
  import org.junit.Test;
  
  public class OrderedCrossoverTest {
  
      @Test
      public void testCrossover() {
          final Integer[] p1 = new Integer[] { 8, 4, 7, 3, 6, 2, 5, 1, 9, 0 };
          final Integer[] p2 = new Integer[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
          final DummyListChromosome p1c = new DummyListChromosome(p1);
          final DummyListChromosome p2c = new DummyListChromosome(p2);
  
          final CrossoverPolicy cp = new OrderedCrossover<>();
  
          for (int i = 0; i < 20; i++) {
              final Set<Integer> parentSet1 = new HashSet<>(Arrays.asList(p1));
              final Set<Integer> parentSet2 = new HashSet<>(Arrays.asList(p2));
  
              final ChromosomePair pair = cp.crossover(p1c, p2c);
  
              final Integer[] c1 = ((DummyListChromosome) pair.getFirst()).getRepresentation().toArray(new Integer[p1.length]);
              final Integer[] c2 = ((DummyListChromosome) pair.getSecond()).getRepresentation().toArray(new Integer[p2.length]);
  
              Assert.assertNotSame(p1c, pair.getFirst());
              Assert.assertNotSame(p2c, pair.getSecond());
  
              // make sure that the children have exactly the same elements as their parents
              for (int j = 0; j < c1.length; j++) {
                  Assert.assertTrue(parentSet1.contains(c1[j]));
                  parentSet1.remove(c1[j]);
                  Assert.assertTrue(parentSet2.contains(c2[j]));
                  parentSet2.remove(c2[j]);
              }
          }
      }
  
      @Test(expected = DimensionMismatchException.class)
      public void testCrossoverDimensionMismatchException() {
          final Integer[] p1 = new Integer[] { 1, 0, 1, 0, 0, 1, 0, 1, 1 };
          final Integer[] p2 = new Integer[] { 0, 1, 1, 0, 1 };
  
          final BinaryChromosome p1c = new DummyBinaryChromosome(p1);
          final BinaryChromosome p2c = new DummyBinaryChromosome(p2);
  
          final CrossoverPolicy cp = new OrderedCrossover<>();
          cp.crossover(p1c, p2c);
      }
  
      @Test(expected = MathIllegalArgumentException.class)
      public void testCrossoverInvalidFixedLengthChromosomeFirst() {
          final Integer[] p1 = new Integer[] { 1, 0, 1, 0, 0, 1, 0, 1, 1 };
          final BinaryChromosome p1c = new DummyBinaryChromosome(p1);
          final Chromosome p2c = new Chromosome() {
              @Override
              public double fitness() {
                  // Not important
                  return 0;
              }
          };
  
          final CrossoverPolicy cp = new OrderedCrossover<>();
          cp.crossover(p1c, p2c);
      }
  
      @Test(expected = MathIllegalArgumentException.class)
      public void testCrossoverInvalidFixedLengthChromosomeSecond() {
          final Integer[] p1 = new Integer[] { 1, 0, 1, 0, 0, 1, 0, 1, 1 };
          final BinaryChromosome p2c = new DummyBinaryChromosome(p1);
          final Chromosome p1c = new Chromosome() {
              @Override
              public double fitness() {
                  // Not important
                  return 0;
              }
          };
 
         final CrossoverPolicy cp = new OrderedCrossover<>();
         cp.crossover(p1c, p2c);
     }
 }