package org.apache.maven.cli.internal;
   
   /*
    * 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.io.File;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.List;
  import java.util.Set;
  
  import javax.inject.Inject;
  import javax.inject.Named;
  
  import org.apache.maven.RepositoryUtils;
  import org.apache.maven.cli.internal.extension.model.CoreExtension;
  import org.apache.maven.execution.MavenExecutionRequest;
  import org.apache.maven.extension.internal.CoreExtensionEntry;
  import org.apache.maven.internal.aether.DefaultRepositorySystemSessionFactory;
  import org.apache.maven.model.Plugin;
  import org.apache.maven.plugin.PluginResolutionException;
  import org.apache.maven.plugin.internal.DefaultPluginDependenciesResolver;
  import org.codehaus.plexus.DefaultPlexusContainer;
  import org.codehaus.plexus.PlexusContainer;
  import org.codehaus.plexus.classworlds.ClassWorld;
  import org.codehaus.plexus.classworlds.realm.ClassRealm;
  import org.codehaus.plexus.logging.Logger;
  import org.eclipse.aether.RepositorySystemSession;
  import org.eclipse.aether.artifact.Artifact;
  import org.eclipse.aether.graph.DependencyFilter;
  import org.eclipse.aether.graph.DependencyNode;
  import org.eclipse.aether.repository.RemoteRepository;
  import org.eclipse.aether.util.filter.ExclusionsDependencyFilter;
  import org.eclipse.aether.util.graph.visitor.PreorderNodeListGenerator;
  
  @Named
  public class BootstrapCoreExtensionManager
  {
      private final Logger log;
  
      private final DefaultPluginDependenciesResolver pluginDependenciesResolver;
  
      private final DefaultRepositorySystemSessionFactory repositorySystemSessionFactory;
  
      private final ClassWorld classWorld;
  
      private final ClassRealm parentRealm;
  
      @Inject
      public BootstrapCoreExtensionManager( Logger log, DefaultPluginDependenciesResolver pluginDependenciesResolver,
                                            DefaultRepositorySystemSessionFactory repositorySystemSessionFactory,
                                            PlexusContainer container )
      {
          this.log = log;
          this.pluginDependenciesResolver = pluginDependenciesResolver;
          this.repositorySystemSessionFactory = repositorySystemSessionFactory;
          this.classWorld = ( (DefaultPlexusContainer) container ).getClassWorld();
          this.parentRealm = container.getContainerRealm();
      }
  
      public List<CoreExtensionEntry> loadCoreExtensions( MavenExecutionRequest request, Set<String> providedArtifacts,
                                                          List<CoreExtension> extensions )
          throws Exception
      {
          RepositorySystemSession repoSession = repositorySystemSessionFactory.newRepositorySession( request );
          List<RemoteRepository> repositories = RepositoryUtils.toRepos( request.getPluginArtifactRepositories() );
  
          return resolveCoreExtensions( repoSession, repositories, providedArtifacts, extensions );
      }
  
      private List<CoreExtensionEntry> resolveCoreExtensions( RepositorySystemSession repoSession,
                                                              List<RemoteRepository> repositories,
                                                              Set<String> providedArtifacts,
                                                              List<CoreExtension> configuration )
          throws Exception
      {
          List<CoreExtensionEntry> extensions = new ArrayList<>();
  
          DependencyFilter dependencyFilter = new ExclusionsDependencyFilter( providedArtifacts );
  
          for ( CoreExtension extension : configuration )
          {
              List<Artifact> artifacts = resolveExtension( extension, repoSession, repositories, dependencyFilter );
             if ( !artifacts.isEmpty() )
             {
                 extensions.add( createExtension( extension, artifacts ) );
             }
         }
 
         return Collections.unmodifiableList( extensions );
     }
 
     private CoreExtensionEntry createExtension( CoreExtension extension, List<Artifact> artifacts )
         throws Exception
     {
         String realmId =
             "coreExtension>" + extension.getGroupId() + ":" + extension.getArtifactId() + ":" + extension.getVersion();
         ClassRealm realm = classWorld.newRealm( realmId, null );
         log.debug( "Populating class realm " + realm.getId() );
         realm.setParentRealm( parentRealm );
         for ( Artifact artifact : artifacts )
         {
             File file = artifact.getFile();
             log.debug( "  Included " + file );
             realm.addURL( file.toURI().toURL() );
         }
         return CoreExtensionEntry.discoverFrom( realm, Collections.singleton( artifacts.get( 0 ).getFile() ) );
     }
 
     private List<Artifact> resolveExtension( CoreExtension extension, RepositorySystemSession repoSession,
                                              List<RemoteRepository> repositories, DependencyFilter dependencyFilter )
         throws PluginResolutionException
     {
         Plugin plugin = new Plugin();
         plugin.setGroupId( extension.getGroupId() );
         plugin.setArtifactId( extension.getArtifactId() );
         plugin.setVersion( extension.getVersion() );
 
         DependencyNode root =
             pluginDependenciesResolver.resolveCoreExtension( plugin, dependencyFilter, repositories, repoSession );
         PreorderNodeListGenerator nlg = new PreorderNodeListGenerator();
         root.accept( nlg );
         List<Artifact> artifacts = nlg.getArtifacts( false );
 
         return artifacts;
     }
 }