package org.apache.maven.index;
   
   /*
    * 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.IOException;
  import java.util.ArrayList;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Set;
  
  import org.apache.lucene.document.Document;
  import org.apache.lucene.index.CorruptIndexException;
  import org.apache.lucene.index.IndexReader;
  import org.apache.lucene.index.Term;
  import org.apache.lucene.search.TermQuery;
  import org.apache.lucene.search.TopScoreDocCollector;
  import org.apache.maven.index.context.IndexingContext;
  import org.codehaus.plexus.logging.AbstractLogEnabled;
  
  /**
   * A default scanning listener
   * 
   * @author Eugene Kuleshov
   */
  class DefaultScannerListener
      extends AbstractLogEnabled
      implements ArtifactScanningListener
  {
      private final IndexingContext context;
  
      private final IndexerEngine indexerEngine;
  
      private final boolean update;
  
      private final ArtifactScanningListener listener;
  
      private final Set<String> uinfos = new HashSet<String>();
  
      private final Set<String> processedUinfos = new HashSet<String>();
  
      private final Set<String> allGroups = new HashSet<String>();
  
      private final Set<String> groups = new HashSet<String>();
  
      private final List<Exception> exceptions = new ArrayList<Exception>();
  
      private int count = 0;
  
      DefaultScannerListener( IndexingContext context, //
                              IndexerEngine indexerEngine, boolean update, //
                              ArtifactScanningListener listener )
      {
          this.context = context;
          this.indexerEngine = indexerEngine;
          this.update = update;
          this.listener = listener;
      }
  
      public void scanningStarted( IndexingContext ctx )
      {
          try
          {
              if ( update )
              {
                  initialize( ctx );
              }
          }
          catch ( IOException ex )
          {
              exceptions.add( ex );
          }
  
          if ( listener != null )
          {
              listener.scanningStarted( ctx );
          }
      }
  
      public void artifactDiscovered( ArtifactContext ac )
      {
          String uinfo = ac.getArtifactInfo().getUinfo();
  
         // TODO: scattered across commented out changes while I was fixing NEXUS-2712, cstamas
         // These changes should be applied by borks too much the fragile indexer
 
         // if ( VersionUtils.isSnapshot( ac.getArtifactInfo().version ) && processedUinfos.contains( uinfo ) )
         if ( processedUinfos.contains( uinfo ) )
         {
             return; // skip individual snapshots
         }
 
         boolean adding = processedUinfos.add( uinfo );
 
         if ( uinfos.contains( uinfo ) )
         {
             // already indexed
             uinfos.remove( uinfo );
             return;
         }
 
         try
         {
             if ( listener != null )
             {
                 listener.artifactDiscovered( ac );
             }
 
             if ( adding )
             {
                 indexerEngine.index( context, ac );
             }
             else
             {
                 indexerEngine.update( context, ac );
             }
 
             for ( Exception e : ac.getErrors() )
             {
                 artifactError( ac, e );
             }
 
             groups.add( ac.getArtifactInfo().getRootGroup() );
             allGroups.add( ac.getArtifactInfo().groupId );
 
             count++;
         }
         catch ( IOException ex )
         {
             artifactError( ac, ex );
         }
     }
 
     public void scanningFinished( IndexingContext ctx, ScanningResult result )
     {
         result.setTotalFiles( count );
 
         for ( Exception ex : exceptions )
         {
             result.addException( ex );
         }
 
         try
         {
             context.optimize();
 
             context.setRootGroups( groups );
 
             context.setAllGroups( allGroups );
 
             if ( update && !context.isReceivingUpdates() )
             {
                 removeDeletedArtifacts( context, result, result.getRequest().getStartingPath() );
             }
         }
         catch ( IOException ex )
         {
             result.addException( ex );
         }
 
         if ( listener != null )
         {
             listener.scanningFinished( ctx, result );
         }
 
         if ( result.getDeletedFiles() > 0 || result.getTotalFiles() > 0 )
         {
             try
             {
                 context.updateTimestamp( true );
 
                 context.optimize();
             }
             catch ( Exception ex )
             {
                 result.addException( ex );
             }
         }
     }
 
     public void artifactError( ArtifactContext ac, Exception e )
     {
         exceptions.add( e );
 
         if ( listener != null )
         {
             listener.artifactError( ac, e );
         }
     }
 
     private void initialize( IndexingContext ctx )
         throws IOException, CorruptIndexException
     {
         IndexReader r = ctx.getIndexReader();
 
         for ( int i = 0; i < r.maxDoc(); i++ )
         {
             if ( !r.isDeleted( i ) )
             {
                 Document d = r.document( i );
 
                 String uinfo = d.get( ArtifactInfo.UINFO );
 
                 if ( uinfo != null )
                 {
                     uinfos.add( uinfo );
 
                     // add all existing groupIds to the lists, as they will
                     // not be "discovered" and would be missing from the new list..
                     String groupId = uinfo.substring( 0, uinfo.indexOf( '|' ) );
                     int n = groupId.indexOf( '.' );
                     groups.add( n == -1 ? groupId : groupId.substring( 0, n ) );
                     allGroups.add( groupId );
                 }
             }
         }
     }
 
     private void removeDeletedArtifacts( IndexingContext context, ScanningResult result, String contextPath )
         throws IOException
     {
         int deleted = 0;
 
         for ( String uinfo : uinfos )
         {
             TopScoreDocCollector collector = TopScoreDocCollector.create( 1, false );
 
             context.getIndexSearcher().search( new TermQuery( new Term( ArtifactInfo.UINFO, uinfo ) ), collector );
 
             if ( collector.getTotalHits() > 0 )
             {
                 String[] ra = ArtifactInfo.FS_PATTERN.split( uinfo );
 
                 ArtifactInfo ai = new ArtifactInfo();
 
                 ai.repository = context.getRepositoryId();
 
                 ai.groupId = ra[0];
 
                 ai.artifactId = ra[1];
 
                 ai.version = ra[2];
 
                 if ( ra.length > 3 )
                 {
                     ai.classifier = ArtifactInfo.renvl( ra[3] );
                 }
 
                 if ( ra.length > 4 )
                 {
                     ai.packaging = ArtifactInfo.renvl( ra[4] );
                 }
 
                 // minimal ArtifactContext for removal
                 ArtifactContext ac = new ArtifactContext( null, null, null, ai, ai.calculateGav() );
 
                 for ( int i = 0; i < collector.getTotalHits(); i++ )
                 {
                     if ( contextPath == null
                         || context.getGavCalculator().gavToPath( ac.getGav() ).startsWith( contextPath ) )
                     {
                         indexerEngine.remove( context, ac );
                     }
 
                     deleted++;
                 }
             }
         }
 
         if ( deleted > 0 )
         {
             context.commit();
         }
 
         result.setDeletedFiles( deleted );
     }
 
 }