package org.apache.maven.repository.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.HashSet;
  import java.util.List;
  import java.util.Set;
  
  import com.google.common.base.Predicate;
  import com.google.common.collect.Iterables;
  import org.apache.maven.model.Parent;
  import org.apache.maven.model.Repository;
  import org.apache.maven.model.building.FileModelSource;
  import org.apache.maven.model.building.ModelSource;
  import org.apache.maven.model.resolution.InvalidRepositoryException;
  import org.apache.maven.model.resolution.ModelResolver;
  import org.apache.maven.model.resolution.UnresolvableModelException;
  import org.eclipse.aether.RepositorySystemSession;
  import org.eclipse.aether.RequestTrace;
  import org.eclipse.aether.artifact.Artifact;
  import org.eclipse.aether.artifact.DefaultArtifact;
  import org.eclipse.aether.impl.ArtifactResolver;
  import org.eclipse.aether.impl.RemoteRepositoryManager;
  import org.eclipse.aether.impl.VersionRangeResolver;
  import org.eclipse.aether.repository.RemoteRepository;
  import org.eclipse.aether.resolution.ArtifactRequest;
  import org.eclipse.aether.resolution.ArtifactResolutionException;
  import org.eclipse.aether.resolution.VersionRangeRequest;
  import org.eclipse.aether.resolution.VersionRangeResolutionException;
  import org.eclipse.aether.resolution.VersionRangeResult;
  
  /**
   * A model resolver to assist building of dependency POMs. This resolver gives priority to those repositories that have
   * been initially specified and repositories discovered in dependency POMs are recessively merged into the search chain.
   * 
   * @author Benjamin Bentmann
   * @see DefaultArtifactDescriptorReader
   */
  class DefaultModelResolver
      implements ModelResolver
  {
  
      private final RepositorySystemSession session;
  
      private final RequestTrace trace;
  
      private final String context;
  
      private List<RemoteRepository> repositories;
  
      private final List<RemoteRepository> externalRepositories;
  
      private final ArtifactResolver resolver;
  
      private final VersionRangeResolver versionRangeResolver;
  
      private final RemoteRepositoryManager remoteRepositoryManager;
  
      private final Set<String> repositoryIds;
  
      public DefaultModelResolver( RepositorySystemSession session, RequestTrace trace, String context,
                                   ArtifactResolver resolver, VersionRangeResolver versionRangeResolver,
                                   RemoteRepositoryManager remoteRepositoryManager, List<RemoteRepository> repositories )
      {
          this.session = session;
          this.trace = trace;
          this.context = context;
          this.resolver = resolver;
          this.versionRangeResolver = versionRangeResolver;
          this.remoteRepositoryManager = remoteRepositoryManager;
          this.repositories = repositories;
          List<RemoteRepository> externalRepositories = new ArrayList<RemoteRepository>();
          externalRepositories.addAll( repositories );
          this.externalRepositories = Collections.unmodifiableList( externalRepositories );
  
          this.repositoryIds = new HashSet<String>();
      }
  
      private DefaultModelResolver( DefaultModelResolver original )
     {
         this.session = original.session;
         this.trace = original.trace;
         this.context = original.context;
         this.resolver = original.resolver;
         this.versionRangeResolver = original.versionRangeResolver;
         this.remoteRepositoryManager = original.remoteRepositoryManager;
         this.repositories = new ArrayList<RemoteRepository>(original.repositories);
         this.externalRepositories = original.externalRepositories;
         this.repositoryIds = new HashSet<String>( original.repositoryIds );
     }
 
     @Override
     public void addRepository( Repository repository )
         throws InvalidRepositoryException
     {
         addRepository( repository, false );
     }
 
     @Override
     public void addRepository(final Repository repository, boolean replace) throws InvalidRepositoryException {
         if ( session.isIgnoreArtifactDescriptorRepositories() )
         {
             return;
         }
 
         if ( !repositoryIds.add( repository.getId() ) ) {
             if ( !replace ) {
                 return;
             }
 
             removeMatchingRepository( repositories, repository.getId() );
         }
 
         List<RemoteRepository> newRepositories =
             Collections.singletonList( ArtifactDescriptorUtils.toRemoteRepository( repository ) );
 
         this.repositories =
             remoteRepositoryManager.aggregateRepositories( session, repositories, newRepositories, true );
     }
 
     private static void removeMatchingRepository(Iterable<RemoteRepository> repositories, final String id) {
         Iterables.removeIf(repositories, new Predicate<RemoteRepository>() {
             @Override
             public boolean apply(RemoteRepository remoteRepository) {
                 return remoteRepository.getId().equals(id);
             }
         });
     }
 
     @Override
     public ModelResolver newCopy()
     {
         return new DefaultModelResolver( this );
     }
 
     @Override
     public ModelSource resolveModel( String groupId, String artifactId, String version )
         throws UnresolvableModelException
     {
         Artifact pomArtifact = new DefaultArtifact( groupId, artifactId, "", "pom", version );
 
         try
         {
             ArtifactRequest request = new ArtifactRequest( pomArtifact, repositories, context );
             request.setTrace( trace );
             pomArtifact = resolver.resolveArtifact( session, request ).getArtifact();
         }
         catch ( ArtifactResolutionException e )
         {
             throw new UnresolvableModelException( e.getMessage(), groupId, artifactId, version, e );
         }
 
         File pomFile = pomArtifact.getFile();
 
         return new FileModelSource( pomFile );
     }
 
     public ModelSource resolveModel( Parent parent )
         throws UnresolvableModelException
     {
         Artifact artifact = new DefaultArtifact( parent.getGroupId(), parent.getArtifactId(), "", "pom",
                                                  parent.getVersion() );
 
         VersionRangeRequest versionRangeRequest = new VersionRangeRequest( artifact, repositories, context );
         versionRangeRequest.setTrace( trace );
 
         try
         {
             VersionRangeResult versionRangeResult =
                 versionRangeResolver.resolveVersionRange( session, versionRangeRequest );
 
             if ( versionRangeResult.getHighestVersion() == null )
             {
                 throw new UnresolvableModelException( "No versions matched the requested range '" + parent.getVersion()
                                                           + "'", parent.getGroupId(), parent.getArtifactId(),
                                                       parent.getVersion() );
 
             }
 
             if ( versionRangeResult.getVersionConstraint() != null
                      && versionRangeResult.getVersionConstraint().getRange() != null
                      && versionRangeResult.getVersionConstraint().getRange().getUpperBound() == null )
             {
                 throw new UnresolvableModelException( "The requested version range '" + parent.getVersion()
                                                           + "' does not specify an upper bound", parent.getGroupId(),
                                                       parent.getArtifactId(), parent.getVersion() );
 
             }
 
             parent.setVersion( versionRangeResult.getHighestVersion().toString() );
         }
         catch ( VersionRangeResolutionException e )
         {
             throw new UnresolvableModelException( e.getMessage(), parent.getGroupId(), parent.getArtifactId(),
                                                   parent.getVersion(), e );
 
         }
 
         return resolveModel( parent.getGroupId(), parent.getArtifactId(), parent.getVersion() );
     }
 
 }