package org.apache.maven.model.management;
   
   /*
    * 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 java.util.ArrayList;
  import java.util.Collections;
  import java.util.LinkedHashMap;
  import java.util.List;
  import java.util.Map;
  
  import javax.inject.Named;
  import javax.inject.Singleton;
  
  import org.apache.maven.api.model.Build;
  import org.apache.maven.api.model.Model;
  import org.apache.maven.api.model.Plugin;
  import org.apache.maven.api.model.PluginContainer;
  import org.apache.maven.api.model.PluginExecution;
  import org.apache.maven.api.model.PluginManagement;
  import org.apache.maven.model.building.ModelBuildingRequest;
  import org.apache.maven.model.building.ModelProblemCollector;
  import org.apache.maven.model.merge.MavenModelMerger;
  
  /**
   * Handles injection of plugin management into the model.
   *
   * @author Benjamin Bentmann
   */
  @SuppressWarnings( { "checkstyle:methodname" } )
  @Named
  @Singleton
  public class DefaultPluginManagementInjector
      implements PluginManagementInjector
  {
  
      private ManagementModelMerger merger = new ManagementModelMerger();
  
      @Override
      public void injectManagement( org.apache.maven.model.Model model, ModelBuildingRequest request,
                                     ModelProblemCollector problems )
      {
          model.update( merger.mergeManagedBuildPlugins( model.getDelegate() ) );
      }
  
      /**
       * ManagementModelMerger
       */
      protected static class ManagementModelMerger
          extends MavenModelMerger
      {
  
          public Model mergeManagedBuildPlugins( Model model )
          {
              Build build = model.getBuild();
              if ( build != null )
              {
                  PluginManagement pluginManagement = build.getPluginManagement();
                  if ( pluginManagement != null )
                  {
                      return model.withBuild( mergePluginContainerPlugins( build, pluginManagement ) );
                  }
              }
              return model;
          }
  
          private Build mergePluginContainerPlugins( Build target, PluginContainer source )
          {
              List<Plugin> src = source.getPlugins();
              if ( !src.isEmpty() )
              {
                  Map<Object, Plugin> managedPlugins = new LinkedHashMap<>( src.size() * 2 );
  
                  Map<Object, Object> context = Collections.emptyMap();
  
                  for ( Plugin element : src )
                  {
                      Object key = getPluginKey().apply( element );
                      managedPlugins.put( key, element );
                  }
  
                  List<Plugin> newPlugins = new ArrayList<>();
                  for ( Plugin element : target.getPlugins() )
                 {
                     Object key = getPluginKey().apply( element );
                     Plugin managedPlugin = managedPlugins.get( key );
                     if ( managedPlugin != null )
                     {
                         element = mergePlugin( element, managedPlugin, false, context );
                     }
                     newPlugins.add( element );
                 }
                 return target.withPlugins( newPlugins );
             }
             return target;
         }
 
         @Override
         protected void mergePlugin_Executions( Plugin.Builder builder, Plugin target, Plugin source,
                                                boolean sourceDominant, Map<Object, Object> context )
         {
             List<PluginExecution> src = source.getExecutions();
             if ( !src.isEmpty() )
             {
                 List<PluginExecution> tgt = target.getExecutions();
 
                 Map<Object, PluginExecution> merged =
                     new LinkedHashMap<>( ( src.size() + tgt.size() ) * 2 );
 
                 for ( PluginExecution element : src )
                 {
                     Object key = getPluginExecutionKey().apply( element );
                     merged.put( key, element );
                 }
 
                 for ( PluginExecution element : tgt )
                 {
                     Object key = getPluginExecutionKey().apply( element );
                     PluginExecution existing = merged.get( key );
                     if ( existing != null )
                     {
                         element = mergePluginExecution( element, existing, sourceDominant, context );
                     }
                     merged.put( key, element );
                 }
 
                 builder.executions( merged.values() );
             }
         }
     }
 
 }