package org.apache.maven.shared.transfer.dependencies.resolve.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.Iterator;
  import java.util.List;
  
  import org.apache.maven.RepositoryUtils;
  import org.apache.maven.artifact.handler.ArtifactHandler;
  import org.apache.maven.artifact.handler.manager.ArtifactHandlerManager;
  import org.apache.maven.model.DependencyManagement;
  import org.apache.maven.model.Model;
  import org.apache.maven.shared.artifact.filter.resolve.TransformableFilter;
  import org.apache.maven.shared.artifact.filter.resolve.transform.EclipseAetherFilterTransformer;
  import org.apache.maven.shared.transfer.dependencies.DependableCoordinate;
  import org.apache.maven.shared.transfer.dependencies.resolve.DependencyResolverException;
  import org.eclipse.aether.RepositorySystem;
  import org.eclipse.aether.RepositorySystemSession;
  import org.eclipse.aether.artifact.Artifact;
  import org.eclipse.aether.artifact.ArtifactType;
  import org.eclipse.aether.artifact.ArtifactTypeRegistry;
  import org.eclipse.aether.artifact.DefaultArtifact;
  import org.eclipse.aether.artifact.DefaultArtifactType;
  import org.eclipse.aether.collection.CollectRequest;
  import org.eclipse.aether.graph.Dependency;
  import org.eclipse.aether.graph.DependencyFilter;
  import org.eclipse.aether.repository.RemoteRepository;
  import org.eclipse.aether.resolution.ArtifactResult;
  import org.eclipse.aether.resolution.DependencyRequest;
  import org.eclipse.aether.resolution.DependencyResolutionException;
  import org.eclipse.aether.resolution.DependencyResult;
  
  /**
   *
   */
  class Maven31DependencyResolver implements MavenDependencyResolver
  {
      private static final Class<?>[] ARG_CLASSES = new Class<?>[] {org.apache.maven.model.Dependency.class,
              ArtifactTypeRegistry.class};
      private final RepositorySystem repositorySystem;
      private final ArtifactHandlerManager artifactHandlerManager;
      private final RepositorySystemSession session;
      private final List<RemoteRepository> aetherRepositories;
  
      Maven31DependencyResolver( RepositorySystem repositorySystem, ArtifactHandlerManager artifactHandlerManager,
              RepositorySystemSession session, List<RemoteRepository> aetherRepositories )
      {
          super();
          this.repositorySystem = repositorySystem;
          this.artifactHandlerManager = artifactHandlerManager;
          this.session = session;
          this.aetherRepositories = aetherRepositories;
      }
  
      /**
       * Based on RepositoryUtils#toDependency(org.apache.maven.model.Dependency, ArtifactTypeRegistry)
       *
       * @param coordinate  {@link DependableCoordinate}
       * @param stereotypes {@link ArtifactTypeRegistry
       * @return as Aether Dependency
       */
      private static Dependency toDependency( DependableCoordinate coordinate, ArtifactTypeRegistry stereotypes )
      {
          ArtifactType stereotype = stereotypes.get( coordinate.getType() );
          if ( stereotype == null )
          {
              stereotype = new DefaultArtifactType( coordinate.getType() );
          }
  
          Artifact artifact = new DefaultArtifact( coordinate.getGroupId(), coordinate.getArtifactId(),
                  coordinate.getClassifier(), null, coordinate.getVersion(), null, stereotype );
  
          return new Dependency( artifact, null );
      }
  
      private static Dependency toDependency( org.apache.maven.model.Dependency root, ArtifactTypeRegistry typeRegistry )
              throws DependencyResolverException
      {
          Object[] args = new Object[] {root, typeRegistry};
 
         return Invoker.invoke( RepositoryUtils.class, "toDependency", ARG_CLASSES, args );
     }
 
     @Override
     // CHECKSTYLE_OFF: LineLength
     public Iterable<org.apache.maven.shared.transfer.artifact.resolve.ArtifactResult> resolveDependencies(
             DependableCoordinate coordinate, TransformableFilter dependencyFilter )
         // CHECKSTYLE_ON: LineLength
             throws DependencyResolverException
     {
         ArtifactTypeRegistry typeRegistry = createTypeRegistry();
 
         Dependency aetherRoot = toDependency( coordinate, typeRegistry );
 
         CollectRequest request = new CollectRequest( aetherRoot, aetherRepositories );
 
         return resolveDependencies( dependencyFilter, request );
     }
 
     private ArtifactTypeRegistry createTypeRegistry() throws DependencyResolverException
     {
         return Invoker.invoke( RepositoryUtils.class, "newArtifactTypeRegistry", ArtifactHandlerManager.class,
                 artifactHandlerManager );
     }
 
     @Override
     // CHECKSTYLE_OFF: LineLength
     public Iterable<org.apache.maven.shared.transfer.artifact.resolve.ArtifactResult> resolveDependencies( Model model,
             TransformableFilter dependencyFilter )
         // CHECKSTYLE_ON: LineLength
             throws DependencyResolverException
     {
         // Are there examples where packaging and type are NOT in sync
         ArtifactHandler artifactHandler = artifactHandlerManager.getArtifactHandler( model.getPackaging() );
 
         String extension = artifactHandler != null ? artifactHandler.getExtension() : null;
 
         Artifact aetherArtifact = new DefaultArtifact( model.getGroupId(), model.getArtifactId(), extension,
                 model.getVersion() );
 
         Dependency aetherRoot = new Dependency( aetherArtifact, null );
 
         CollectRequest request = new CollectRequest( aetherRoot, aetherRepositories );
 
         request.setDependencies( resolveDependencies( model.getDependencies() ) );
 
         DependencyManagement mavenDependencyManagement = model.getDependencyManagement();
         if ( mavenDependencyManagement != null )
         {
             request.setManagedDependencies( resolveDependencies( model.getDependencyManagement().getDependencies() ) );
         }
 
         return resolveDependencies( dependencyFilter, request );
     }
 
     /**
      * @param mavenDependencies {@link org.apache.maven.model.Dependency} can be {@code null}.
      * @return List of resolved dependencies.
      * @throws DependencyResolverException in case of a failure of the typeRegistry error.
      */
     // CHECKSTYLE_OFF: LineLength
     private List<Dependency> resolveDependencies( Collection<org.apache.maven.model.Dependency> mavenDependencies )
             throws DependencyResolverException
     // CHECKSTYLE_ON: LineLength
     {
         if ( mavenDependencies == null )
         {
             return Collections.emptyList();
         }
 
         ArtifactTypeRegistry typeRegistry = createTypeRegistry();
 
         List<Dependency> aetherDependencies = new ArrayList<>( mavenDependencies.size() );
 
         for ( org.apache.maven.model.Dependency mavenDependency : mavenDependencies )
         {
             aetherDependencies.add( toDependency( mavenDependency, typeRegistry ) );
         }
 
         return aetherDependencies;
     }
 
     @Override
     // CHECKSTYLE_OFF: LineLength
     public Iterable<org.apache.maven.shared.transfer.artifact.resolve.ArtifactResult> resolveDependencies(
             Collection<org.apache.maven.model.Dependency> mavenDependencies,
             Collection<org.apache.maven.model.Dependency> managedMavenDependencies, TransformableFilter filter )
         // CHECKSTYLE_ON: LineLength
             throws DependencyResolverException
     {
 
         List<Dependency> aetherDeps = resolveDependencies( mavenDependencies );
 
         List<Dependency> aetherManagedDependencies = resolveDependencies( managedMavenDependencies );
 
         CollectRequest request = new CollectRequest( aetherDeps, aetherManagedDependencies, aetherRepositories );
 
         return resolveDependencies( filter, request );
     }
 
     // CHECKSTYLE_OFF: LineLength
     private Iterable<org.apache.maven.shared.transfer.artifact.resolve.ArtifactResult> resolveDependencies(
             TransformableFilter dependencyFilter, CollectRequest request ) throws DependencyResolverException
     // CHECKSTYLE_ON: LineLength
     {
         try
         {
             DependencyFilter depFilter = null;
             if ( dependencyFilter != null )
             {
                 depFilter = dependencyFilter.transform( new EclipseAetherFilterTransformer() );
             }
 
             DependencyRequest depRequest = new DependencyRequest( request, depFilter );
 
             final DependencyResult dependencyResults = repositorySystem.resolveDependencies( session, depRequest );
 
             // Keep it lazy! Often artifactsResults aren't used, so transforming up front is too expensive
             return new Iterable<org.apache.maven.shared.transfer.artifact.resolve.ArtifactResult>()
             {
                 @Override
                 public Iterator<org.apache.maven.shared.transfer.artifact.resolve.ArtifactResult> iterator()
                 {
                     // CHECKSTYLE_OFF: LineLength
                     Collection<org.apache.maven.shared.transfer.artifact.resolve.ArtifactResult> artResults = new ArrayList<>(
                             dependencyResults.getArtifactResults().size() );
                     // CHECKSTYLE_ON: LineLength
 
                     for ( ArtifactResult artifactResult : dependencyResults.getArtifactResults() )
                     {
                         artResults.add( new Maven31ArtifactResult( artifactResult ) );
                     }
 
                     return artResults.iterator();
                 }
             };
         }
         catch ( DependencyResolutionException e )
         {
             throw new Maven31DependencyResolverException( e );
         }
     }
 }