package org.apache.maven.plugin.dependency;
   
   /*
    * 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.io.IOException;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  
  import org.apache.maven.artifact.Artifact;
  import org.apache.maven.artifact.ArtifactUtils;
  import org.apache.maven.artifact.factory.ArtifactFactory;
  import org.apache.maven.artifact.metadata.ArtifactMetadataSource;
  import org.apache.maven.artifact.repository.ArtifactRepository;
  import org.apache.maven.artifact.resolver.ArtifactNotFoundException;
  import org.apache.maven.artifact.resolver.ArtifactResolutionException;
  import org.apache.maven.artifact.resolver.ArtifactResolutionResult;
  import org.apache.maven.artifact.resolver.ArtifactResolver;
  import org.apache.maven.artifact.versioning.VersionRange;
  import org.apache.maven.model.Dependency;
  import org.apache.maven.plugin.AbstractMojo;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugin.MojoFailureException;
  import org.apache.maven.project.MavenProject;
  import org.codehaus.plexus.util.FileUtils;
  
  /**
   * Remove the project dependencies from the local repository, and optionally
   * re-resolve them.
   * 
   * @author jdcasey
   * @since 2.0
   * @goal purge-local-repository
   * @aggregator
   * @version $Id: PurgeLocalRepositoryMojo.java 1085777 2011-03-26 18:13:19Z hboutemy $
   * 
   */
  public class PurgeLocalRepositoryMojo
      extends AbstractMojo
  {
  
      public static final String FILE_FUZZINESS = "file";
  
      public static final String VERSION_FUZZINESS = "version";
  
      public static final String ARTIFACT_ID_FUZZINESS = "artifactId";
  
      public static final String GROUP_ID_FUZZINESS = "groupId";
  
      /**
       * The projects in the current build. Each of these is subject to
       * refreshing.
       * 
       * @parameter default-value="${reactorProjects}"
       * @required
       * @readonly
       */
      private List<MavenProject> projects;
  
      /**
       * The list of dependencies in the form of groupId:artifactId which should
       * NOT be deleted/refreshed. This is useful for third-party artifacts.
       * 
       * @parameter
       */
      private List<String> excludes;
  
      /**
       * Comma-separated list of groupId:artifactId entries, which should be used
       * to exclude artifacts from deletion/refresh. This is a command-line
       * alternative to the <code>excludes</code> parameter, since List
       * parameters are not currently compatible with CLI specification.
       * 
       * @parameter expression="${exclude}"
       */
     private String exclude;
 
     /**
      * Whether to re-resolve the artifacts once they have been deleted from the
      * local repository. If you are running this mojo from the command-line, you
      * may want to disable this. By default, artifacts will be re-resolved.
      * 
      * @parameter expression="${reResolve}" default-value="true"
      */
     private boolean reResolve;
 
     /**
      * The local repository, from which to delete artifacts.
      * 
      * @parameter default-value="${localRepository}"
      * @required
      * @readonly
      */
     private ArtifactRepository localRepository;
 
     /**
      * The artifact resolver used to re-resolve dependencies, if that option is
      * enabled.
      * 
      * @component
      */
     private ArtifactResolver resolver;
 
     /**
      * The artifact metadata source used to resolve dependencies
      * 
      * @component
      */
     private ArtifactMetadataSource source;
 
     /**
      * Determines how liberally the plugin will delete an artifact from the
      * local repository. Values are: <br/>
      * <ul>
      * <li><b>file</b> <i>(default)</i> - Eliminate only the artifact's file.</li>
      * <li><b>version</b> - Eliminate all files associated with the artifact's
      * version.</li>
      * <li><b>artifactId</b> - Eliminate all files associated with the
      * artifact's artifactId.</li>
      * <li><b>groupId</b> - Eliminate all files associated with the artifact's
      * groupId.</li>
      * </ul>
      * 
      * @parameter expression="${resolutionFuzziness}" default-value="file"
      */
     private String resolutionFuzziness;
 
     /**
      * Whether this mojo should act on all transitive dependencies. Default
      * value is true.
      * 
      * @parameter expression="${actTransitively}" default-value="true"
      */
     private boolean actTransitively;
 
     /**
      * Used to construct artifacts for deletion/resolution...
      * 
      * @component
      */
     private ArtifactFactory factory;
 
     /**
      * Whether this plugin should output verbose messages. Default is false.
      * 
      * @parameter expression="${verbose}" default-value="false"
      */
     private boolean verbose;
 
     public void execute()
         throws MojoExecutionException, MojoFailureException
     {
         List<String> exclusionPatterns = buildExclusionPatternsList();
 
         for ( MavenProject project : projects )
         {
             try
             {
                 refreshDependenciesForProject( project, exclusionPatterns );
             }
             catch ( ArtifactResolutionException e )
             {
                 MojoFailureException failure = new MojoFailureException( this,
                                                                          "Failed to refresh project dependencies for: "
                                                                              + project.getId(),
                                                                          "Artifact resolution failed for project: "
                                                                              + project.getId() );
                 failure.initCause( e );
 
                 throw failure;
             }
         }
     }
 
     private List<String> buildExclusionPatternsList()
     {
         List<String> patterns = new ArrayList<String>();
 
         if ( exclude != null )
         {
             String[] elements = exclude.split( " ?, ?" );
 
             patterns.addAll( Arrays.asList( elements ) );
         }
         else if ( excludes != null && !excludes.isEmpty() )
         {
             patterns.addAll( excludes );
         }
 
         return patterns;
     }
 
     private Map<String, Artifact> createArtifactMap( MavenProject project )
     {
         Map<String, Artifact> artifactMap = Collections.emptyMap();
 
         List<Dependency> dependencies = project.getDependencies();
 
         List<ArtifactRepository> remoteRepositories = Collections.emptyList();
 
         Set<Artifact> dependencyArtifacts = new HashSet<Artifact>();
 
         for ( Dependency dependency : dependencies )
         {
             VersionRange vr = VersionRange.createFromVersion( dependency.getVersion() );
 
             Artifact artifact = factory.createDependencyArtifact( dependency.getGroupId(), dependency.getArtifactId(),
                                                                   vr, dependency.getType(), dependency.getClassifier(),
                                                                   dependency.getScope() );
             dependencyArtifacts.add( artifact );
         }
 
         if ( actTransitively )
         {
             try
             {
                 ArtifactResolutionResult result = resolver.resolveTransitively( dependencyArtifacts, project
                     .getArtifact(), remoteRepositories, localRepository, source );
 
                 artifactMap = ArtifactUtils.artifactMapByVersionlessId( result.getArtifacts() );
             }
             catch ( ArtifactResolutionException e )
             {
                 verbose( "Skipping: " + e.getArtifactId() + ". It cannot be resolved." );
             }
             catch ( ArtifactNotFoundException e )
             {
                 verbose( "Skipping: " + e.getArtifactId() + ". It cannot be resolved." );
             }
         }
         else
         {
             artifactMap = new HashMap<String, Artifact>();
             for ( Artifact artifact : dependencyArtifacts )
             {
                 try
                 {
                     resolver.resolve( artifact, remoteRepositories, localRepository );
 
                     artifactMap.put( ArtifactUtils.versionlessKey( artifact ), artifact );
                 }
                 catch ( ArtifactResolutionException e )
                 {
                     verbose( "Skipping: " + e.getArtifactId() + ". It cannot be resolved." );
                 }
                 catch ( ArtifactNotFoundException e )
                 {
                     verbose( "Skipping: " + e.getArtifactId() + ". It cannot be resolved." );
                 }
             }
         }
 
         return artifactMap;
     }
 
     private void verbose( String message )
     {
         if ( verbose || getLog().isDebugEnabled() )
         {
             getLog().info( message );
         }
     }
 
     private void refreshDependenciesForProject( MavenProject project, List<String> exclusionPatterns )
         throws ArtifactResolutionException, MojoFailureException
     {
         Map<String, Artifact> deps = createArtifactMap( project );
 
         if ( deps.isEmpty() )
         {
             getLog().info( "Nothing to do for project: " + project.getId() );
             return;
         }
 
         if ( !exclusionPatterns.isEmpty() )
         {
             for ( String excludedKey : exclusionPatterns )
             {
                 if ( GROUP_ID_FUZZINESS.equals( resolutionFuzziness ) )
                 {
                     verbose( "Excluding groupId: " + excludedKey + " from refresh operation for project: "
                         + project.getId() );
 
                     for ( Iterator<Map.Entry<String, Artifact>> deps_it = deps.entrySet().iterator(); deps_it.hasNext(); )
                     {
                         Map.Entry<String, Artifact> dependency = deps_it.next();
             			
             			Artifact artifact = dependency.getValue();
             			
                         if ( artifact.getGroupId().equals( excludedKey ) )
             			{
             				deps_it.remove();
             			}
             		}
             	}
             	else
             	{
 	                verbose( "Excluding: " + excludedKey + " from refresh operation for project: " + project.getId() );
 	
 	                deps.remove( excludedKey );
             	}
             }
         }
 
         verbose( "Processing dependencies for project: " + project.getId() );
 
         List<Artifact> missingArtifacts = new ArrayList<Artifact>();
         for ( Map.Entry<String, Artifact> entry : deps.entrySet() )
         {
             Artifact artifact = entry.getValue();
 
             verbose( "Processing artifact: " + artifact.getId() );
 
             File deleteTarget = findDeleteTarget( artifact );
 
             verbose( "Deleting: " + deleteTarget );
 
             if ( deleteTarget.isDirectory() )
             {
                 try
                 {
                     FileUtils.deleteDirectory( deleteTarget );
                 }
                 catch ( IOException e )
                 {
                     throw new MojoFailureException( this, "Cannot delete dependency from the local repository: "
                         + artifact.getId(), "Failed to delete: " + deleteTarget );
                 }
             }
             else
             {
                 deleteTarget.delete();
             }
 
             if ( reResolve )
             {
                 verbose( "Re-resolving." );
 
                 artifact.setResolved( false );
 
                 try
                 {
                     resolver.resolveAlways( artifact, project.getRemoteArtifactRepositories(), localRepository );
                 }
                 catch ( ArtifactResolutionException e )
                 {
                     getLog().debug( e.getMessage() );
                     missingArtifacts.add( artifact );
                 }
                 catch ( ArtifactNotFoundException e )
                 {
                     getLog().debug( e.getMessage() );
                     missingArtifacts.add( artifact );
                 }
             }
         }
 
         if ( missingArtifacts.size() > 0 )
         {
             String message = "required artifacts missing:\n";
             for ( Artifact missingArtifact : missingArtifacts )
             {
                 message += "  " + missingArtifact.getId() + "\n";
             }
             message += "\nfor the artifact:";
 
             throw new ArtifactResolutionException( message, project.getArtifact(), project
                 .getRemoteArtifactRepositories() );
         }
 
     }
 
     private File findDeleteTarget( Artifact artifact )
     {
         File deleteTarget = artifact.getFile();
 
         if ( GROUP_ID_FUZZINESS.equals( resolutionFuzziness ) )
         {
             // get the artifactId dir.
             deleteTarget = deleteTarget.getParentFile().getParentFile();
 
             // get the first groupId dir.
             deleteTarget = deleteTarget.getParentFile();
 
             String[] path = localRepository.pathOf( artifact ).split( "\\/" );
 
             // subtract the artifact filename, version dir, artifactId dir, and
             // the first groupId
             // dir, since we've accounted for those above.
             int groupParts = path.length - 4;
 
             File parent = deleteTarget.getParentFile();
             int count = 0;
             while ( count++ < groupParts )
             {
                 // prune empty dirs back to the beginning of the groupId, if
                 // possible.
 
                 // if the parent dir only has the one child file, then it's okay
                 // to prune.
                 if ( parent.list().length < 2 )
                 {
                     deleteTarget = parent;
 
                     // check the parent of this newly checked dir
                     parent = deleteTarget.getParentFile();
                 }
                 else
                 {
                     // if there are more files than the one that we're
                     // interested in killing, stop.
                     break;
                 }
             }
 
         }
         else if ( ARTIFACT_ID_FUZZINESS.equals( resolutionFuzziness ) )
         {
             // get the artifactId dir.
             deleteTarget = deleteTarget.getParentFile().getParentFile();
         }
         else if ( VERSION_FUZZINESS.equals( resolutionFuzziness ) )
         {
             // get the version dir.
             deleteTarget = deleteTarget.getParentFile();
         }
         // else it's file fuzziness.
 
         return deleteTarget;
     }
 
 }