package org.apache.maven.surefire.api.util;
   
   /*
    * 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.
   */
  
  import org.apache.maven.surefire.api.runorder.RunEntryStatisticsMap;
  import org.apache.maven.surefire.api.testset.RunOrderParameters;
  
  import java.util.ArrayList;
  import java.util.Calendar;
  import java.util.Collections;
  import java.util.Comparator;
  import java.util.LinkedHashSet;
  import java.util.List;
  import java.util.Random;
  
  /**
   * Applies the final runorder of the tests
   *
   * @author Kristian Rosenvold
   */
  public class DefaultRunOrderCalculator
      implements RunOrderCalculator
  {
      private final Comparator<Class<?>> sortOrder;
  
      private final RunOrder[] runOrder;
  
      private final RunOrderParameters runOrderParameters;
  
      private final int threadCount;
  
      private final Random random;
  
      public DefaultRunOrderCalculator( RunOrderParameters runOrderParameters, int threadCount )
      {
          this.runOrderParameters = runOrderParameters;
          this.threadCount = threadCount;
          this.runOrder = runOrderParameters.getRunOrder();
          this.sortOrder = this.runOrder.length > 0 ? getSortOrderComparator( this.runOrder[0] ) : null;
          Long runOrderRandomSeed = runOrderParameters.getRunOrderRandomSeed();
          random = new Random( runOrderRandomSeed == null ? System.nanoTime() : runOrderRandomSeed );
      }
  
      @Override
      @SuppressWarnings( "checkstyle:magicnumber" )
      public TestsToRun orderTestClasses( TestsToRun scannedClasses )
      {
          List<Class<?>> result = new ArrayList<>( 512 );
  
          for ( Class<?> scannedClass : scannedClasses )
          {
              result.add( scannedClass );
          }
  
          orderTestClasses( result, runOrder.length != 0 ? runOrder[0] : null );
          return new TestsToRun( new LinkedHashSet<>( result ) );
      }
  
      private void orderTestClasses( List<Class<?>> testClasses, RunOrder runOrder )
      {
          if ( RunOrder.RANDOM.equals( runOrder ) )
          {
              Collections.shuffle( testClasses, random );
          }
          else if ( RunOrder.FAILEDFIRST.equals( runOrder ) )
          {
              RunEntryStatisticsMap stat = RunEntryStatisticsMap.fromFile( runOrderParameters.getRunStatisticsFile() );
              List<Class<?>> prioritized = stat.getPrioritizedTestsByFailureFirst( testClasses );
              testClasses.clear();
              testClasses.addAll( prioritized );
  
          }
          else if ( RunOrder.BALANCED.equals( runOrder ) )
          {
              RunEntryStatisticsMap stat = RunEntryStatisticsMap.fromFile( runOrderParameters.getRunStatisticsFile() );
              List<Class<?>> prioritized = stat.getPrioritizedTestsClassRunTime( testClasses, threadCount );
              testClasses.clear();
              testClasses.addAll( prioritized );
  
          }
          else if ( sortOrder != null )
          {
             testClasses.sort( sortOrder );
         }
     }
 
     private static Comparator<Class<?>> getSortOrderComparator( RunOrder runOrder )
     {
         if ( RunOrder.ALPHABETICAL.equals( runOrder ) )
         {
             return getAlphabeticalComparator();
         }
         else if ( RunOrder.REVERSE_ALPHABETICAL.equals( runOrder ) )
         {
             return getReverseAlphabeticalComparator();
         }
         else if ( RunOrder.HOURLY.equals( runOrder ) )
         {
             final int hour = Calendar.getInstance().get( Calendar.HOUR_OF_DAY );
             return ( ( hour % 2 ) == 0 ) ? getAlphabeticalComparator() : getReverseAlphabeticalComparator();
         }
         else
         {
             return null;
         }
     }
 
     private static Comparator<Class<?>> getReverseAlphabeticalComparator()
     {
         return ( o1, o2 ) -> o2.getName().compareTo( o1.getName() );
     }
 
     private static Comparator<Class<?>> getAlphabeticalComparator()
     {
         return Comparator.comparing( Class::getName );
     }
 }