import junit.framework.TestCase;

import org.infinispan.commons.hash.MurmurHash3;
import org.infinispan.util.TimSort;

import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

/*
 * Copyright (C) 2012 eXo Platform SAS.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

/**
 * @author <a href="mailto:nfilotto@exoplatform.com">Nicolas Filotto</a>
 * @version $Id$
 *
 */
public class TestSort extends TestCase
{
   private static final Object[] sorted = {new MyClass("eba5a419c0a8010335b4955eb93af680"),
      new MyClass("eba5a419c0a8010360a883f7e28db72a[http://www.jcp.org/jcr/1.0]primaryType:1PROPERTY"),
      new MyClass("eba5a419c0a8010360a883f7e28db72a"), new MyClass("eba5a419c0a8010360a883f7e28db72a"),
      new MyClass("eba5a419c0a8010335b4955eb93af680"), new MyClass("eba5a419c0a8010346b8b39050146684"),
      new MyClass("eba5a419c0a8010360a883f7e28db72a"),
      new MyClass("00exo0jcr0root0uuid0000000000000[]reindex_test:1NODE"),
      new MyClass("eba5a419c0a80103093445685cb11408"),
      new MyClass("eba5a419c0a8010335b4955eb93af680[http://www.jcp.org/jcr/1.0]primaryType:1PROPERTY"),
      new MyClass("eba5a419c0a80103093445685cb11408"), new MyClass("00exo0jcr0root0uuid0000000000000"),
      new MyClass("eba5a419c0a80103093445685cb11408[http://www.jcp.org/jcr/1.0]primaryType:1PROPERTY"),
      new MyClass("eba5a416c0a801031df214fd06357c25"), new MyClass("eba5a419c0a8010360a883f7e28db72a"),
      new MyClass("eba5a419c0a8010335b4955eb93af680[]sub1.1:1NODE"), new MyClass("eba5a419c0a80103093445685cb11408"),
      new MyClass("eba5a419c0a8010335b4955eb93af680"), new MyClass("eba5a419c0a8010360a883f7e28db72a"),
      new MyClass("eba5a419c0a8010362ba69dd7c08b9db"), new MyClass("eba5a419c0a8010335b4955eb93af680"),
      new MyClass("eba5a416c0a801037fc94ebc3a5d4c9f"), new MyClass("eba5a419c0a8010360a883f7e28db72a[]sub1:1NODE"),
      new MyClass("eba5a419c0a80103093445685cb11408"), new MyClass("eba5a416c0a801031df214fd06357c25"),
      new MyClass("00exo0jcr0root0uuid0000000000000"), new MyClass("eba5a416c0a801031df214fd06357c25"),
      new MyClass("eba5a416c0a801031df214fd06357c25"), new MyClass("eba5a419c0a80103093445685cb11408"),
      new MyClass("eba5a419c0a8010360a883f7e28db72a"), new MyClass("eba5a416c0a801031df214fd06357c25"),
      new MyClass("eba5a419c0a80103661be6cb1b767b0c")};

   public void testSortWithSimpleComparator() throws Exception
   {
      Comparator<Object> keyComparator = new Comparator<Object>()
      {
         public int compare(Object o1, Object o2)
         {
            return ((Comparable<Object>)o1).compareTo(o2);
         }
      };
      testSort(keyComparator);
   }

   public void testSortWithMurmurHash3() throws Exception
   {

      Comparator<Object> keyComparator = new Comparator<Object>()
      {
         private final MurmurHash3 hash = new MurmurHash3();

         public int compare(Object o1, Object o2)
         {
            return hash.hash(o1) - hash.hash(o2);
         }
      };
      testSort(keyComparator);
   }

   private static void testSort(Comparator<Object> keyComparator)
   {
      for (int i = 0; i < 1000000; i++)
      {
         List<Object> values = Arrays.asList(sorted);
         Collections.shuffle(values);
         try
         {
            TimSort.sort(values.toArray(new Object[]{}), keyComparator);
         }
         catch (Exception e)
         {
            System.err.println("Failed with :");
            for (Object o : values)
            {
               System.err.println(o);
            }
            fail("It fails with at least the array printed into the console, with the following error message: "
               + e.getMessage());
         }
      }
   }

   public static class MyClass implements Comparable<MyClass>
   {
      private final String value;

      protected MyClass(String value)
      {
         super();
         this.value = value;
      }

      /**
       * @see java.lang.Object#hashCode()
       */
      @Override
      public int hashCode()
      {
         final int prime = 31;
         int result = 1;
         result = prime * result + ((value == null) ? 0 : value.hashCode());
         return result;
      }

      /**
       * @see java.lang.Object#equals(java.lang.Object)
       */
      @Override
      public boolean equals(Object obj)
      {
         if (this == obj)
            return true;
         if (obj == null)
            return false;
         if (getClass() != obj.getClass())
            return false;
         MyClass other = (MyClass)obj;
         if (value == null)
         {
            if (other.value != null)
               return false;
         }
         else if (!value.equals(other.value))
            return false;
         return true;
      }

      public String toString()
      {
         return value;
      }

      /**
       * @see java.lang.Comparable#compareTo(java.lang.Object)
       */
      public int compareTo(MyClass myClass)
      {
         return value.compareTo(myClass.value);
      }
   }
}