package org.apache.maven.shared.dependency.graph.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.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Set;
  
  import org.apache.maven.RepositoryUtils;
  import org.apache.maven.artifact.Artifact;
  import org.apache.maven.artifact.resolver.filter.ArtifactFilter;
  import org.apache.maven.project.DefaultDependencyResolutionRequest;
  import org.apache.maven.project.DependencyResolutionException;
  import org.apache.maven.project.DependencyResolutionRequest;
  import org.apache.maven.project.DependencyResolutionResult;
  import org.apache.maven.project.MavenProject;
  import org.apache.maven.project.ProjectBuildingRequest;
  import org.apache.maven.project.ProjectDependenciesResolver;
  import org.apache.maven.shared.dependency.graph.DependencyGraphBuilder;
  import org.apache.maven.shared.dependency.graph.DependencyGraphBuilderException;
  import org.apache.maven.shared.dependency.graph.DependencyNode;
  import org.codehaus.plexus.component.annotations.Component;
  import org.codehaus.plexus.component.annotations.Requirement;
  import org.codehaus.plexus.logging.AbstractLogEnabled;
  import org.sonatype.aether.graph.Dependency;
  import org.sonatype.aether.version.VersionConstraint;
  
  /**
   * Wrapper around Maven 3 dependency resolver.
   *
   * @see ProjectDependenciesResolver
   * @author Hervé Boutemy
   * @since 2.0
   */
  @Component( role = DependencyGraphBuilder.class, hint = "maven3" )
  public class Maven3DependencyGraphBuilder
      extends AbstractLogEnabled
      implements DependencyGraphBuilder
  {
      @Requirement
      private ProjectDependenciesResolver resolver;
  
      /**
       * Builds the dependency graph for Maven 3.
       *
       * @param buildingRequest the buildingRequest
       * @param filter artifact filter (can be <code>null</code>)
       * @return DependencyNode containing the dependency graph.
       * @throws DependencyGraphBuilderException if some of the dependencies could not be resolved.
       */
      @Override
      public DependencyNode buildDependencyGraph( ProjectBuildingRequest buildingRequest, ArtifactFilter filter )
          throws DependencyGraphBuilderException
      {
          return buildDependencyGraph( buildingRequest, filter, null );
      }
  
      /**
       * Builds the dependency graph for Maven 3, eventually hacking for collecting projects from
       * reactor not yet built.
       *
       * @param buildingRequest the buildingRequest
       * @param filter artifact filter (can be <code>null</code>)
       * @param reactorProjects Collection of those projects contained in the reactor (can be <code>null</code>).
       * @return DependencyNode containing the dependency graph.
       * @throws DependencyGraphBuilderException if some of the dependencies could not be resolved.
       */
      @Override
      public DependencyNode buildDependencyGraph( ProjectBuildingRequest buildingRequest, ArtifactFilter filter,
                                                  Collection<MavenProject> reactorProjects )
          throws DependencyGraphBuilderException
      {
          MavenProject project = buildingRequest.getProject();
  
          DependencyResolutionRequest request =
              new DefaultDependencyResolutionRequest( project, buildingRequest.getRepositorySession() );
  
          DependencyResolutionResult result = resolveDependencies( request, reactorProjects );
  
         return buildDependencyNode( null, result.getDependencyGraph(), project.getArtifact(), filter );
     }
 
     private DependencyResolutionResult resolveDependencies( DependencyResolutionRequest request,
                                                             Collection<MavenProject> reactorProjects )
         throws DependencyGraphBuilderException
     {
         try
         {
             return resolver.resolve( request );
         }
         catch ( DependencyResolutionException e )
         {
             if ( reactorProjects == null )
             {
                 throw new DependencyGraphBuilderException( "Could not resolve following dependencies: "
                     + e.getResult().getUnresolvedDependencies(), e );
             }
 
             // try collecting from reactor
             return collectDependenciesFromReactor( e, reactorProjects );
         }
     }
 
     private DependencyResolutionResult collectDependenciesFromReactor( DependencyResolutionException e,
                                                                        Collection<MavenProject> reactorProjects )
         throws DependencyGraphBuilderException
     {
         DependencyResolutionResult result = e.getResult();
 
         List<Dependency> reactorDeps = getReactorDependencies( reactorProjects, result.getUnresolvedDependencies() );
 
         result.getUnresolvedDependencies().removeAll( reactorDeps );
         Invoker.invoke( result.getResolvedDependencies(), "addAll", Collection.class, reactorDeps );
 
         if ( !result.getUnresolvedDependencies().isEmpty() )
         {
             throw new DependencyGraphBuilderException( "Could not resolve nor collect following dependencies: "
                 + result.getUnresolvedDependencies(), e );
         }
 
         return result;
     }
 
     private List<org.sonatype.aether.graph.Dependency> getReactorDependencies( Collection<MavenProject> reactorProjects,
                                                                                List<?> dependencies )
     {
         Set<ArtifactKey> reactorProjectsIds = new HashSet<ArtifactKey>();
         for ( MavenProject project : reactorProjects )
         {
             reactorProjectsIds.add( new ArtifactKey( project ) );
         }
 
         List<Dependency> reactorDeps = new ArrayList<Dependency>();
         for ( Object untypedDependency : dependencies )
         {
             Dependency dependency = (Dependency) untypedDependency;
             org.sonatype.aether.artifact.Artifact depArtifact = dependency.getArtifact();
 
             ArtifactKey key =
                 new ArtifactKey( depArtifact.getGroupId(), depArtifact.getArtifactId(), depArtifact.getVersion() );
 
             if ( reactorProjectsIds.contains( key ) )
             {
                 reactorDeps.add( dependency );
             }
         }
 
         return reactorDeps;
     }
 
     private Artifact getDependencyArtifact( Dependency dep )
     {
         Artifact mavenArtifact = RepositoryUtils.toArtifact( dep.getArtifact() );
         
         mavenArtifact.setScope( dep.getScope() );
         
         return mavenArtifact; 
     }
 
     private DependencyNode buildDependencyNode( DependencyNode parent, org.sonatype.aether.graph.DependencyNode node,
                                                 Artifact artifact, ArtifactFilter filter )
     {
         DefaultDependencyNode current =
             new DefaultDependencyNode( parent, artifact,
                                        null /* node.getPremanagedVersion() */,
                                        null /* node.getPremanagedScope() */,
                                        getVersionSelectedFromRange( node.getVersionConstraint() ) );
 
         List<DependencyNode> nodes = new ArrayList<DependencyNode>( node.getChildren().size() );
         for ( org.sonatype.aether.graph.DependencyNode child : node.getChildren() )
         {
             Artifact childArtifact = getDependencyArtifact( child.getDependency() );
 
             if ( ( filter == null ) || filter.include( childArtifact ) )
             {
                 nodes.add( buildDependencyNode( current, child, childArtifact, filter ) );
             }
         }
 
         current.setChildren( Collections.unmodifiableList( nodes ) );
 
         return current;
     }
 
     private String getVersionSelectedFromRange( VersionConstraint constraint )
     {
         if ( ( constraint == null ) || ( constraint.getVersion() != null ) )
         {
             return null;
         }
 
         StringBuilder sb = new StringBuilder();
         for ( org.sonatype.aether.version.VersionRange range : constraint.getRanges() )
         {
             if ( sb.length() > 0 )
             {
                 sb.append( ',' );
             }
             sb.append( range );
         }
 
         return sb.toString();
     }
 }