package org.apache.maven.plugins.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.HashSet;
  import java.util.LinkedHashSet;
  import java.util.List;
  import java.util.Set;
  
  import org.apache.maven.artifact.Artifact;
  import org.apache.maven.artifact.ArtifactUtils;
  import org.apache.maven.artifact.handler.manager.ArtifactHandlerManager;
  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.filter.ArtifactFilter;
  import org.apache.maven.execution.MavenSession;
  import org.apache.maven.model.Dependency;
  import org.apache.maven.plugin.AbstractMojo;
  import org.apache.maven.plugin.MojoExecution;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugin.MojoFailureException;
  import org.apache.maven.plugin.MojoExecution.Source;
  import org.apache.maven.plugins.annotations.Component;
  import org.apache.maven.plugins.annotations.Mojo;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.apache.maven.project.MavenProject;
  import org.apache.maven.shared.dependencies.resolve.DependencyResolver;
  import org.apache.maven.shared.dependencies.resolve.DependencyResolverException;
  import org.apache.maven.shared.artifact.DefaultArtifactCoordinate;
  import org.apache.maven.shared.artifact.filter.resolve.AbstractFilter;
  import org.apache.maven.shared.artifact.filter.resolve.AndFilter;
  import org.apache.maven.shared.artifact.filter.resolve.Node;
  import org.apache.maven.shared.artifact.filter.resolve.PatternExclusionsFilter;
  import org.apache.maven.shared.artifact.filter.resolve.PatternInclusionsFilter;
  import org.apache.maven.shared.artifact.filter.resolve.ScopeFilter;
  import org.apache.maven.shared.artifact.filter.resolve.TransformableFilter;
  import org.apache.maven.shared.artifact.filter.resolve.transform.ArtifactIncludeFilterTransformer;
  import org.apache.maven.shared.artifact.resolve.ArtifactResolver;
  import org.apache.maven.shared.artifact.resolve.ArtifactResolverException;
  import org.apache.maven.shared.artifact.resolve.ArtifactResult;
  import org.codehaus.plexus.util.FileUtils;
  import org.codehaus.plexus.util.StringUtils;
  
  /**
   * When run on a project, remove the project dependencies from the local repository, and optionally re-resolve them.
   * Outside of a project, remove the manually given dependencies.
   *
   * @author jdcasey
   * @since 2.0
   */
  @Mojo( name = "purge-local-repository", threadSafe = true, requiresProject = false )
  public class PurgeLocalRepositoryMojo
      extends AbstractMojo
  {
  
      private static final String VERSION_FUZZINESS = "version";
  
      private static final String ARTIFACT_ID_FUZZINESS = "artifactId";
  
      private static final String GROUP_ID_FUZZINESS = "groupId";
  
      /**
       * The Maven projects in the reactor.
       */
      @Parameter( defaultValue = "${reactorProjects}", readonly = true, required = true )
      private List<MavenProject> reactorProjects;
  
      /**
       * The current Maven project.
       */
      @Parameter( defaultValue = "${project}", readonly = true, required = true )
      private MavenProject project;
  
      @Parameter( defaultValue = "${session}", readonly = true, required = true )
      private MavenSession session;
  
      /**
      * This mojo execution, used to determine if it was launched from the lifecycle or the command-line.
      */
     @Parameter( defaultValue = "${mojo}", required = true, readonly = true )
     private MojoExecution mojoExecution;
 
     /**
      * Artifact handler manager.
      */
     @Component
     private ArtifactHandlerManager artifactHandlerManager;
 
     /**
      * The list of dependencies in the form of groupId:artifactId which should BE deleted/purged from the local
      * repository. Note that using this parameter will deactivate the normal process for purging the current project
      * dependency tree. If this parameter is used, only the included artifacts will be purged. The manualIncludes
      * parameter should not be used in combination with the includes/excludes parameters.
      *
      * @since 2.6
      */
     @Parameter
     private List<String> manualIncludes;
 
     /**
      * Comma-separated list of groupId:artifactId entries, which should be used to manually include artifacts for
      * deletion. This is a command-line alternative to the <code>manualIncludes</code> parameter, since List parameters
      * are not currently compatible with CLI specification.
      *
      * @since 2.6
      */
     @Parameter( property = "manualInclude" )
     private String manualInclude;
 
     /**
      * The list of dependencies in the form of groupId:artifactId which should BE deleted/refreshed.
      *
      * @since 2.6
      */
     @Parameter
     private List<String> includes;
 
     /**
      * Comma-separated list of groupId:artifactId entries, which should be used to include artifacts for
      * deletion/refresh. This is a command-line alternative to the <code>includes</code> parameter, since List
      * parameters are not currently compatible with CLI specification.
      *
      * @since 2.6
      */
     @Parameter( property = "include" )
     private String include;
 
     /**
      * The list of dependencies in the form of groupId:artifactId which should NOT be deleted/refreshed.
      */
     @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( property = "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( property = "reResolve", defaultValue = "true" )
     private boolean reResolve;
 
     /**
      * The local repository, from which to delete artifacts.
      */
     @Parameter( defaultValue = "${localRepository}", readonly = true, required = true )
     private ArtifactRepository localRepository;
 
     /**
      * The dependency resolver
      */
     @Component
     private DependencyResolver dependencyResolver;
 
     /**
      * The artifact resolver used to re-resolve dependencies, if that option is enabled.
      */
     @Component
     private ArtifactResolver artifactResolver;
 
     /**
      * Determines how liberally the plugin will delete an artifact from the local repository. Values are: <br/>
      * <ul>
      * <li><b>file</b> - Eliminate only the artifact's file.</li>
      * <li><b>version</b> <i>(default)</i> - Eliminate all files associated with the version of the artifact.</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( property = "resolutionFuzziness", defaultValue = "version" )
     private String resolutionFuzziness;
 
     /**
      * Whether this mojo should act on all transitive dependencies. Default value is true.
      */
     @Parameter( property = "actTransitively", defaultValue = "true" )
     private boolean actTransitively;
 
     /**
      * Whether this plugin should output verbose messages. Default is false.
      */
     @Parameter( property = "verbose", defaultValue = "false" )
     private boolean verbose;
 
     /**
      * Whether to purge only snapshot artifacts.
      *
      * @since 2.4
      */
     @Parameter( property = "snapshotsOnly", defaultValue = "false" )
     private boolean snapshotsOnly;
 
     /**
      * Skip plugin execution completely.
      *
      * @since 2.7
      */
     @Parameter( property = "skip", defaultValue = "false" )
     private boolean skip;
 
     /**
      * Includes only direct project dependencies.
      */
     private class DirectDependencyFilter
         extends AbstractFilter
     {
 
         private Artifact projectArtifact;
 
         private List<Dependency> directDependencies;
 
         /**
          * Default constructor
          *
          * @param directDependencies Set of dependencies objects which represent the direct dependencies of the project
          */
         DirectDependencyFilter( Artifact projectArtifact, List<Dependency> directDependencies )
         {
             this.projectArtifact = projectArtifact;
             this.directDependencies = directDependencies;
         }
 
         @Override
         public boolean accept( Node node, List<Node> parents )
         {
 
             if ( artifactsGAMatch( node, projectArtifact.getGroupId(), projectArtifact.getArtifactId() ) )
             {
                 return true;
             }
             for ( Dependency dep : directDependencies )
             {
                 if ( this.artifactsGAMatch( node, dep.getGroupId(), dep.getArtifactId() ) )
                 {
                     return true;
                 }
             }
             return false;
         }
 
         /*
          * Compare the groupId:artifactId of two artifacts.
          */
         private boolean artifactsGAMatch( Node node, String groupId, String artifactId )
         {
             if ( node.getDependency() == null )
             {
                 return false;
             }
 
             if ( !node.getDependency().getGroupId().equals( groupId ) )
             {
                 getLog().debug( "Different groupId: " + node.getDependency() + "  " + groupId );
                 return false;
             }
             if ( !node.getDependency().getArtifactId().equals( artifactId ) )
             {
                 getLog().debug( "Different artifactId: " + node.getDependency() + "  " + artifactId );
                 return false;
             }
             return true;
         }
     }
 
     /**
      * Includes only snapshot artifacts
      */
     private class SnapshotsFilter
         extends AbstractFilter
     {
         @Override
         public boolean accept( Node node, List<Node> parents )
         {
             if ( node.getDependency() == null )
             {
                 return false;
             }
             else
             {
                 return ArtifactUtils.isSnapshot( node.getDependency().getVersion() );
             }
         }
     }
 
     @Override
     public void execute()
         throws MojoExecutionException, MojoFailureException
     {
         if ( isSkip() )
         {
             getLog().info( "Skipping plugin execution" );
             return;
         }
 
         if ( !StringUtils.isEmpty( manualInclude ) )
         {
             manualIncludes = this.parseIncludes( manualInclude );
         }
         // If it's a manual purge, the only step is to delete from the local repo
         if ( manualIncludes != null && manualIncludes.size() > 0 )
         {
             manualPurge( manualIncludes );
             return;
         }
 
         Set<Artifact> purgedArtifacts = new HashSet<Artifact>();
         if ( shouldPurgeAllProjectsInReactor() )
         {
             for ( MavenProject reactorProject : reactorProjects )
             {
                 purgeLocalRepository( reactorProject, purgedArtifacts );
             }
         }
         else
         {
             purgeLocalRepository( project, purgedArtifacts );
         }
     }
 
     /**
      * Determines if all projects in the reactor should be purged from their dependencies. When this goal is started on
      * the command-line, it is always the case. When it is bound to a phase in the lifecycle, it is never the case.
      * 
      * @return <code>true</code> if all projects in the reactor should be purged, <code>false</code> otherwise.
      */
     private boolean shouldPurgeAllProjectsInReactor()
     {
         Source source = mojoExecution.getSource();
         return reactorProjects.size() > 1 && source == Source.CLI;
     }
 
     /**
      * Purges the local repository for the dependencies in the given Maven project.
      *
      * @param theProject Maven project.
      * @param resolvedArtifactsToPurge The artifacts that were already purged.
      * @throws MojoFailureException in case of errors during the purge.
      */
     private void purgeLocalRepository( MavenProject theProject, Set<Artifact> purgedArtifacts )
         throws MojoFailureException
     {
         List<Dependency> dependencies = theProject.getDependencies();
 
         TransformableFilter dependencyFilter = createPurgeArtifactsFilter( theProject, dependencies, purgedArtifacts );
 
         Set<Artifact> resolvedArtifactsToPurge =
             getFilteredResolvedArtifacts( theProject, dependencies, dependencyFilter );
 
         if ( resolvedArtifactsToPurge.isEmpty() )
         {
             getLog().info( "No artifacts included for purge for project: " + theProject.getId() );
             return;
         }
 
         verbose( "Purging dependencies for project: " + theProject.getId() );
         purgeArtifacts( resolvedArtifactsToPurge );
         purgedArtifacts.addAll( resolvedArtifactsToPurge );
 
         if ( reResolve )
         {
             ArtifactFilter artifactFilter = dependencyFilter.transform( new ArtifactIncludeFilterTransformer() );
             try
             {
                 reResolveArtifacts( theProject, resolvedArtifactsToPurge, artifactFilter );
             }
             catch ( ArtifactResolutionException e )
             {
                 String failureMessage = "Failed to refresh project dependencies for: " + theProject.getId();
                 MojoFailureException failure = new MojoFailureException( failureMessage );
                 failure.initCause( e );
 
                 throw failure;
             }
             catch ( ArtifactNotFoundException e )
             {
                 String failureMessage = "Failed to refresh project dependencies for: " + theProject.getId();
                 MojoFailureException failure = new MojoFailureException( failureMessage );
                 failure.initCause( e );
 
                 throw failure;
             }
         }
     }
 
     /**
      * Purge/Delete artifacts from the local repository according to the given patterns.
      *
      * @param theIncludes The includes.
      * @throws MojoExecutionException in case of an error.
      */
     private void manualPurge( List<String> theIncludes )
         throws MojoExecutionException
     {
         for ( String gavPattern : theIncludes )
         {
             if ( StringUtils.isEmpty( gavPattern ) )
             {
                 getLog().debug( "Skipping empty gav pattern: " + gavPattern );
                 continue;
             }
 
             String relativePath = gavToPath( gavPattern );
             if ( StringUtils.isEmpty( relativePath ) )
             {
                 continue;
             }
 
             File purgeDir = new File( localRepository.getBasedir(), relativePath );
             if ( purgeDir.exists() )
             {
                 getLog().debug( "Deleting directory: " + purgeDir );
                 try
                 {
                     FileUtils.deleteDirectory( purgeDir );
                 }
                 catch ( IOException e )
                 {
                     throw new MojoExecutionException( "Unable to purge directory: " + purgeDir );
                 }
             }
         }
     }
 
     /**
      * Convert a groupId:artifactId:version to a file system path
      *
      * @param gav, the groupId:artifactId:version string
      * @return the corresponding path
      */
     private String gavToPath( String gav )
     {
         if ( StringUtils.isEmpty( gav ) )
         {
             return null;
         }
 
         String[] pathComponents = gav.split( ":" );
 
         StringBuilder path = new StringBuilder( pathComponents[0].replace( '.', '/' ) );
 
         for ( int i = 1; i < pathComponents.length; ++i )
         {
             path.append( "/" ).append( pathComponents[i] );
         }
 
         return path.toString();
     }
 
     /**
      * Create the includes exclude filter to use when resolving and purging dependencies Also excludes any "system"
      * scope dependencies
      *
      * @param theProject The Maven project.
      * @param dependencies The dependencies to use as a reference if we're excluding transitive dependencies
      * @param purgedArtifacts The artifacts already purged.
      * @return the created filter
      */
     private TransformableFilter createPurgeArtifactsFilter( MavenProject theProject, List<Dependency> dependencies,
                                                             Set<Artifact> purgedArtifacts )
     {
         List<TransformableFilter> subFilters = new ArrayList<TransformableFilter>();
 
         // System dependencies should never be purged
         subFilters.add( ScopeFilter.excluding( Artifact.SCOPE_SYSTEM ) );
 
         if ( this.snapshotsOnly )
         {
             subFilters.add( new SnapshotsFilter() );
         }
 
         // The CLI includes/excludes overrides configuration in the pom
         if ( !StringUtils.isEmpty( this.include ) )
         {
             this.includes = parseIncludes( this.include );
         }
         if ( this.includes != null )
         {
             subFilters.add( new PatternInclusionsFilter( includes ) );
         }
 
         if ( !StringUtils.isEmpty( this.exclude ) )
         {
             this.excludes = parseIncludes( this.exclude );
         }
         if ( this.excludes != null )
         {
             subFilters.add( new PatternExclusionsFilter( excludes ) );
         }
 
         if ( !actTransitively )
         {
             subFilters.add( new DirectDependencyFilter( theProject.getArtifact(), dependencies ) );
         }
 
         List<String> exclusions = new ArrayList<String>( reactorProjects.size() );
         // It doesn't make sense to include projects from the reactor here since they're likely not able to be resolved
         for ( MavenProject reactorProject : reactorProjects )
         {
             exclusions.add( toPatternExcludes( reactorProject.getArtifact() ) );
         }
         // There is no need to consider a second time artifacts that were already purged (re-resolved or not)
         for ( Artifact purgedArtifact : purgedArtifacts )
         {
             exclusions.add( toPatternExcludes( purgedArtifact ) );
         }
         subFilters.add( new PatternExclusionsFilter( exclusions ) );
 
         return new AndFilter( subFilters );
     }
 
     /**
      * Returns a string that represents a pattern for an exclude filter for the given artifact.
      *
      * @param artifact Artifact.
      * @return String representation of a pattern for an exclude filter for the given artifact.
      */
     private String toPatternExcludes( Artifact artifact )
     {
         return artifact.getGroupId() + ":" + artifact.getArtifactId() + ":"
             + artifact.getArtifactHandler().getExtension() + ":" + artifact.getVersion();
     }
 
     /**
      * Convert comma separated list of includes to List object
      *
      * @param theInclude The list of includes
      * @return the includes list
      */
     private List<String> parseIncludes( String theInclude )
     {
         List<String> theIncludes = new ArrayList<String>();
 
         if ( theInclude != null )
         {
             String[] elements = theInclude.split( "," );
             theIncludes.addAll( Arrays.asList( elements ) );
         }
 
         return theIncludes;
     }
 
     private Set<Artifact> getFilteredResolvedArtifacts( MavenProject theProject, List<Dependency> dependencies,
                                                         TransformableFilter filter )
     {
         try
         {
             Iterable<ArtifactResult> results =
                 dependencyResolver.resolveDependencies( session.getProjectBuildingRequest(), theProject.getModel(),
                                                         filter );
 
             Set<Artifact> resolvedArtifacts = new LinkedHashSet<Artifact>();
 
             for ( ArtifactResult artResult : results )
             {
                 resolvedArtifacts.add( artResult.getArtifact() );
             }
 
             return resolvedArtifacts;
         }
         catch ( DependencyResolverException e )
         {
             getLog().info( "Unable to resolve all dependencies for: " + theProject.getGroupId() + ":"
                 + theProject.getArtifactId() + ":" + theProject.getVersion()
                 + ". Falling back to non-transitive mode for initial artifact resolution." );
         }
 
         Set<Artifact> resolvedArtifacts = new LinkedHashSet<Artifact>();
 
         ArtifactFilter artifactFilter = filter.transform( new ArtifactIncludeFilterTransformer() );
 
         for ( Dependency dependency : dependencies )
         {
             DefaultArtifactCoordinate coordinate = new DefaultArtifactCoordinate();
             coordinate.setGroupId( dependency.getGroupId() );
             coordinate.setArtifactId( dependency.getArtifactId() );
             coordinate.setVersion( dependency.getVersion() );
             coordinate.setExtension( artifactHandlerManager.getArtifactHandler( dependency.getType() ).getExtension() );
             try
             {
                 Artifact artifact =
                     artifactResolver.resolveArtifact( session.getProjectBuildingRequest(), coordinate ).getArtifact();
                 if ( artifactFilter.include( artifact ) )
                 {
                     resolvedArtifacts.add( artifact );
                 }
             }
             catch ( ArtifactResolverException e )
             {
                 getLog().debug( "Unable to resolve artifact: " + coordinate );
             }
         }
         return resolvedArtifacts;
     }
 
     private void purgeArtifacts( Set<Artifact> artifacts )
         throws MojoFailureException
     {
         for ( Artifact artifact : artifacts )
         {
             verbose( "Purging artifact: " + artifact.getId() );
 
             File deleteTarget = findDeleteTarget( artifact );
 
             verbose( "Deleting: " + deleteTarget );
 
             if ( deleteTarget.isDirectory() )
             {
                 try
                 {
                     FileUtils.deleteDirectory( deleteTarget );
                 }
                 catch ( IOException e )
                 {
                     getLog().warn( "Unable to purge local repository location: " + deleteTarget, e );
                 }
             }
             else
             {
                 if ( !deleteTarget.delete() )
                 {
                     deleteTarget.deleteOnExit();
                     getLog().warn( "Unable to purge local repository location immediately: " + deleteTarget );
                 }
             }
             artifact.setResolved( false );
         }
     }
 
     private void reResolveArtifacts( MavenProject theProject, Set<Artifact> artifacts, ArtifactFilter filter )
         throws ArtifactResolutionException, ArtifactNotFoundException
     {
 
         // Always need to re-resolve the poms in case they were purged along with the artifact
         // because Maven 2 will not automatically re-resolve them when resolving the artifact
         for ( Artifact artifact : artifacts )
         {
             try
             {
                 //CHECKSTYLE_OFF: LineLength
                 artifactResolver.resolveArtifact( session.getProjectBuildingRequest(),
                                                   org.apache.maven.shared.artifact.TransferUtils.toArtifactCoordinate( artifact ) );
                 //CHECKSTYLE_ON: LineLength
             }
             catch ( ArtifactResolverException e )
             {
                 verbose( e.getMessage() );
             }
         }
 
         List<Artifact> missingArtifacts = new ArrayList<Artifact>();
 
         for ( Artifact artifact : artifacts )
         {
             verbose( "Resolving artifact: " + artifact.getId() );
 
             try
             {
                 artifactResolver.resolveArtifact( session.getProjectBuildingRequest(), artifact );
             }
             catch ( ArtifactResolverException e )
             {
                 verbose( e.getMessage() );
                 missingArtifacts.add( artifact );
             }
         }
 
         if ( missingArtifacts.size() > 0 )
         {
             StringBuffer message = new StringBuffer( "required artifacts missing:\n" );
             for ( Artifact missingArtifact : missingArtifacts )
             {
                 message.append( "  " ).append( missingArtifact.getId() ).append( '\n' );
             }
             message.append( "\nfor the artifact:" );
 
             throw new ArtifactResolutionException( message.toString(), theProject.getArtifact(),
                                                    theProject.getRemoteArtifactRepositories() );
         }
     }
 
     private File findDeleteTarget( Artifact artifact )
     {
         // Use localRepository.pathOf() in case artifact.getFile() is not set
         File deleteTarget = new File( localRepository.getBasedir(), localRepository.pathOf( artifact ) );
 
         if ( GROUP_ID_FUZZINESS.equals( resolutionFuzziness ) )
         {
             // get the groupId dir.
             deleteTarget = deleteTarget.getParentFile().getParentFile().getParentFile();
         }
         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;
     }
 
     private void verbose( String message )
     {
         if ( verbose || getLog().isDebugEnabled() )
         {
             getLog().info( message );
         }
     }
 
     /**
      * @return {@link #skip}
      */
     public boolean isSkip()
     {
         return skip;
     }
 
     /**
      * @param skip {@link #skip}
      */
     public void setSkip( boolean skip )
     {
         this.skip = skip;
     }
 }