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.util.Properties;
  
  import org.eclipse.aether.DefaultRepositorySystemSession;
  import org.eclipse.aether.artifact.DefaultArtifactType;
  import org.eclipse.aether.collection.DependencyGraphTransformer;
  import org.eclipse.aether.collection.DependencyManager;
  import org.eclipse.aether.collection.DependencySelector;
  import org.eclipse.aether.collection.DependencyTraverser;
  import org.eclipse.aether.impl.ArtifactDescriptorReader;
  import org.eclipse.aether.impl.DefaultServiceLocator;
  import org.eclipse.aether.impl.MetadataGeneratorFactory;
  import org.eclipse.aether.impl.VersionRangeResolver;
  import org.eclipse.aether.impl.VersionResolver;
  import org.eclipse.aether.util.artifact.DefaultArtifactTypeRegistry;
  import org.eclipse.aether.util.graph.manager.ClassicDependencyManager;
  import org.eclipse.aether.util.graph.selector.AndDependencySelector;
  import org.eclipse.aether.util.graph.selector.ExclusionDependencySelector;
  import org.eclipse.aether.util.graph.selector.OptionalDependencySelector;
  import org.eclipse.aether.util.graph.selector.ScopeDependencySelector;
  import org.eclipse.aether.util.graph.transformer.ChainedDependencyGraphTransformer;
  import org.eclipse.aether.util.graph.transformer.ConflictResolver;
  import org.eclipse.aether.util.graph.transformer.JavaDependencyContextRefiner;
  import org.eclipse.aether.util.graph.transformer.JavaScopeDeriver;
  import org.eclipse.aether.util.graph.transformer.JavaScopeSelector;
  import org.eclipse.aether.util.graph.transformer.NearestVersionSelector;
  import org.eclipse.aether.util.graph.transformer.SimpleOptionalitySelector;
  import org.eclipse.aether.util.graph.traverser.FatArtifactTraverser;
  import org.eclipse.aether.util.repository.SimpleArtifactDescriptorPolicy;
  
  /**
   * A utility class to assist in setting up a Maven-like repository system. <em>Note:</em> This component is meant to
   * assist those clients that employ the repository system outside of an IoC container, Maven plugins should instead
   * always use regular dependency injection to acquire the repository system.
   *
   * @author Benjamin Bentmann
   */
  public final class MavenRepositorySystemUtils
  {
  
      private MavenRepositorySystemUtils()
      {
          // hide constructor
      }
  
      /**
       * Creates a new service locator that already knows about all service implementations included in this library. To
       * acquire a complete repository system, clients need to add some repository connectors for remote transfers.
       *
       * @return The new service locator, never {@code null}.
       */
      public static DefaultServiceLocator newServiceLocator()
      {
          DefaultServiceLocator locator = new DefaultServiceLocator();
          locator.addService( ArtifactDescriptorReader.class, DefaultArtifactDescriptorReader.class );
          locator.addService( VersionResolver.class, DefaultVersionResolver.class );
          locator.addService( VersionRangeResolver.class, DefaultVersionRangeResolver.class );
          locator.addService( MetadataGeneratorFactory.class, SnapshotMetadataGeneratorFactory.class );
          locator.addService( MetadataGeneratorFactory.class, VersionsMetadataGeneratorFactory.class );
          return locator;
      }
  
      /**
       * Creates a new Maven-like repository system session by initializing the session with values typical for
       * Maven-based resolution. In more detail, this method configures settings relevant for the processing of dependency
       * graphs, most other settings remain at their generic default value. Use the various setters to further configure
       * the session with authentication, mirror, proxy and other information required for your environment.
       *
       * @return The new repository system session, never {@code null}.
       */
      public static DefaultRepositorySystemSession newSession()
      {
          DefaultRepositorySystemSession session = new DefaultRepositorySystemSession();
  
          DependencyTraverser depTraverser = new FatArtifactTraverser();
          session.setDependencyTraverser( depTraverser );
  
          DependencyManager depManager = new ClassicDependencyManager();
          session.setDependencyManager( depManager );
 
         DependencySelector depFilter =
             new AndDependencySelector( new ScopeDependencySelector( "test", "provided" ),
                                        new OptionalDependencySelector(), new ExclusionDependencySelector() );
         session.setDependencySelector( depFilter );
 
         DependencyGraphTransformer transformer =
             new ConflictResolver( new NearestVersionSelector(), new JavaScopeSelector(),
                                   new SimpleOptionalitySelector(), new JavaScopeDeriver() );
         new ChainedDependencyGraphTransformer( transformer, new JavaDependencyContextRefiner() );
         session.setDependencyGraphTransformer( transformer );
 
         DefaultArtifactTypeRegistry stereotypes = new DefaultArtifactTypeRegistry();
         stereotypes.add( new DefaultArtifactType( "pom" ) );
         stereotypes.add( new DefaultArtifactType( "maven-plugin", "jar", "", "java" ) );
         stereotypes.add( new DefaultArtifactType( "jar", "jar", "", "java" ) );
         stereotypes.add( new DefaultArtifactType( "ejb", "jar", "", "java" ) );
         stereotypes.add( new DefaultArtifactType( "ejb-client", "jar", "client", "java" ) );
         stereotypes.add( new DefaultArtifactType( "test-jar", "jar", "tests", "java" ) );
         stereotypes.add( new DefaultArtifactType( "javadoc", "jar", "javadoc", "java" ) );
         stereotypes.add( new DefaultArtifactType( "java-source", "jar", "sources", "java", false, false ) );
         stereotypes.add( new DefaultArtifactType( "war", "war", "", "java", false, true ) );
         stereotypes.add( new DefaultArtifactType( "ear", "ear", "", "java", false, true ) );
         stereotypes.add( new DefaultArtifactType( "rar", "rar", "", "java", false, true ) );
         stereotypes.add( new DefaultArtifactType( "par", "par", "", "java", false, true ) );
         session.setArtifactTypeRegistry( stereotypes );
 
         session.setArtifactDescriptorPolicy( new SimpleArtifactDescriptorPolicy( true, true ) );
 
         final Properties systemProperties = new Properties();
         
         // MNG-5670 guard against ConcurrentModificationException
         // MNG-6053 guard against key without value
         Properties sysProp = System.getProperties();
         synchronized ( sysProp )
         {
             systemProperties.putAll( sysProp );
         }
 
         session.setSystemProperties( systemProperties );
         session.setConfigProperties( systemProperties );
 
         return session;
     }
 
 }