package org.apache.maven.project;
   
   /*
    * 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 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.sonatype.aether.RepositorySystemSession;
  import org.sonatype.aether.artifact.Artifact;
  import org.sonatype.aether.impl.ArtifactResolver;
  import org.sonatype.aether.impl.RemoteRepositoryManager;
  import org.sonatype.aether.repository.RemoteRepository;
  import org.sonatype.aether.repository.RepositoryPolicy;
  import org.sonatype.aether.resolution.ArtifactRequest;
  import org.sonatype.aether.resolution.ArtifactResolutionException;
  import org.sonatype.aether.util.artifact.DefaultArtifact;
  
  /**
   * A model resolver to assist building of projects. This resolver gives priority to those repositories that have been
   * declared in the POM.
   * 
   * @author Benjamin Bentmann
   */
  class ProjectModelResolver
      implements ModelResolver
  {
  
      private final RepositorySystemSession session;
  
      private final String context = "project";
  
      private List<RemoteRepository> repositories;
  
      private List<RemoteRepository> pomRepositories;
  
      private final List<RemoteRepository> externalRepositories;
  
      private final ArtifactResolver resolver;
  
      private final RemoteRepositoryManager remoteRepositoryManager;
  
      private final Set<String> repositoryIds;
  
      private final ReactorModelPool modelPool;
  
      private final ProjectBuildingRequest.RepositoryMerging repositoryMerging;
  
      public ProjectModelResolver( RepositorySystemSession session, ArtifactResolver resolver,
                                   RemoteRepositoryManager remoteRepositoryManager, List<RemoteRepository> repositories,
                                   ProjectBuildingRequest.RepositoryMerging repositoryMerging, ReactorModelPool modelPool )
      {
          this.session = session;
          this.resolver = resolver;
          this.remoteRepositoryManager = remoteRepositoryManager;
          this.pomRepositories = new ArrayList<RemoteRepository>();
          this.externalRepositories = repositories;
          this.repositories = repositories;
          this.repositoryMerging = repositoryMerging;
          this.repositoryIds = new HashSet<String>();
          this.modelPool = modelPool;
      }
  
      private ProjectModelResolver( ProjectModelResolver original )
      {
          this.session = original.session;
          this.resolver = original.resolver;
          this.remoteRepositoryManager = original.remoteRepositoryManager;
          this.pomRepositories = original.pomRepositories;
          this.externalRepositories = original.externalRepositories;
          this.repositories = original.repositories;
          this.repositoryMerging = original.repositoryMerging;
          this.repositoryIds = new HashSet<String>( original.repositoryIds );
         this.modelPool = original.modelPool;
     }
 
     public void addRepository( Repository repository )
         throws InvalidRepositoryException
     {
         if ( !repositoryIds.add( repository.getId() ) )
         {
             return;
         }
 
         List<RemoteRepository> newRepositories = Collections.singletonList( convert( repository ) );
 
         if ( ProjectBuildingRequest.RepositoryMerging.REQUEST_DOMINANT.equals( repositoryMerging ) )
         {
             repositories = remoteRepositoryManager.aggregateRepositories( session, repositories, newRepositories, true );
         }
         else
         {
             pomRepositories =
                 remoteRepositoryManager.aggregateRepositories( session, pomRepositories, newRepositories, true );
             repositories =
                 remoteRepositoryManager.aggregateRepositories( session, pomRepositories, externalRepositories, false );
         }
     }
 
     private static RemoteRepository convert( Repository repository )
     {
         RemoteRepository result =
             new RemoteRepository( repository.getId(), repository.getLayout(), repository.getUrl() );
         result.setPolicy( true, convert( repository.getSnapshots() ) );
         result.setPolicy( false, convert( repository.getReleases() ) );
         return result;
     }
 
     private static RepositoryPolicy convert( org.apache.maven.model.RepositoryPolicy policy )
     {
         boolean enabled = true;
         String checksums = RepositoryPolicy.CHECKSUM_POLICY_WARN;
         String updates = RepositoryPolicy.UPDATE_POLICY_DAILY;
 
         if ( policy != null )
         {
             enabled = policy.isEnabled();
             if ( policy.getUpdatePolicy() != null )
             {
                 updates = policy.getUpdatePolicy();
             }
             if ( policy.getChecksumPolicy() != null )
             {
                 checksums = policy.getChecksumPolicy();
             }
         }
 
         return new RepositoryPolicy( enabled, updates, checksums );
     }
 
     public ModelResolver newCopy()
     {
         return new ProjectModelResolver( this );
     }
 
     public ModelSource resolveModel( String groupId, String artifactId, String version )
         throws UnresolvableModelException
     {
         File pomFile = null;
 
         if ( modelPool != null )
         {
             pomFile = modelPool.get( groupId, artifactId, version );
         }
 
         if ( pomFile == null )
         {
             Artifact pomArtifact = new DefaultArtifact( groupId, artifactId, "", "pom", version );
 
             try
             {
                 ArtifactRequest request = new ArtifactRequest( pomArtifact, repositories, context );
                 pomArtifact = resolver.resolveArtifact( session, request ).getArtifact();
             }
             catch ( ArtifactResolutionException e )
             {
                 throw new UnresolvableModelException( e.getMessage(), groupId, artifactId, version, e );
             }
 
             pomFile = pomArtifact.getFile();
         }
 
         return new FileModelSource( pomFile );
     }
 
 }