package org.apache.maven.plugins.pmd;
   
   /*
    * 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.FileReader;
  import java.io.IOException;
  import java.io.LineNumberReader;
  import java.util.ArrayList;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Set;
  
  import org.apache.commons.lang3.StringUtils;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugins.pmd.model.CpdFile;
  import org.apache.maven.plugins.pmd.model.Duplication;
  
  import net.sourceforge.pmd.cpd.Mark;
  import net.sourceforge.pmd.cpd.Match;
  
  /**
   * This class contains utility methods to load property files which define which files
   * should be excluded from the CPD duplication results.
   * See property <code>pmd.excludeFromFailureFile</code>.
   *
   * @author Andreas Dangel
   */
  public class ExcludeDuplicationsFromFile implements ExcludeFromFile<Duplication>
  {
  
      private final List<Set<String>> exclusionList = new ArrayList<>();
  
      @Override
      public boolean isExcludedFromFailure( final Duplication errorDetail )
      {
          final Set<String> uniquePaths = new HashSet<>();
          for ( final CpdFile cpdFile : errorDetail.getFiles() )
          {
              uniquePaths.add( cpdFile.getPath() );
          }
          return isExcludedFromFailure( uniquePaths );
      }
  
      /**
       * Checks whether the given {@link Match} is excluded.
       * Note: The exclusion must have been loaded before via {@link #loadExcludeFromFailuresData(String)}.
       * 
       * @param errorDetail the duplication to check
       * @return <code>true</code> if the given duplication should be excluded, <code>false</code> otherwise.
       */
      public boolean isExcludedFromFailure( final Match errorDetail )
      {
          final Set<String> uniquePaths = new HashSet<>();
          for ( Mark mark : errorDetail.getMarkSet() )
          {
              uniquePaths.add( mark.getFilename() );
          }
          return isExcludedFromFailure( uniquePaths );
      }
  
      private boolean isExcludedFromFailure( Set<String> uniquePaths )
      {
          for ( final Set<String> singleExclusionGroup : exclusionList )
          {
              if ( uniquePaths.size() == singleExclusionGroup.size()
                  && duplicationExcludedByGroup( uniquePaths, singleExclusionGroup ) )
              {
                  return true;
              }
          }
          return false;
      }
  
      private boolean duplicationExcludedByGroup( final Set<String> uniquePaths, final Set<String> singleExclusionGroup )
      {
          for ( final String path : uniquePaths )
          {
              if ( !fileExcludedByGroup( path, singleExclusionGroup ) )
              {
                  return false;
              }
          }
         return true;
     }
 
     private boolean fileExcludedByGroup( final String path, final Set<String> singleExclusionGroup )
     {
         final String formattedPath = path.replace( '\\', '.' ).replace( '/', '.' );
         for ( final String className : singleExclusionGroup )
         {
             if ( formattedPath.contains( className ) )
             {
                 return true;
             }
         }
         return false;
     }
 
     @Override
     public void loadExcludeFromFailuresData( final String excludeFromFailureFile )
             throws MojoExecutionException
     {
         if ( StringUtils.isEmpty( excludeFromFailureFile ) )
         {
             return;
         }
 
         try ( LineNumberReader reader = new LineNumberReader( new FileReader( excludeFromFailureFile ) ) )
         {
             String line;
             while ( ( line = reader.readLine() ) != null )
             {
                 if ( !line.startsWith( "#" ) )
                 {
                     exclusionList.add( createSetFromExclusionLine( line ) );
                 }
             }
         }
         catch ( final IOException e )
         {
             throw new MojoExecutionException( "Cannot load file " + excludeFromFailureFile, e );
         }
     }
 
     private Set<String> createSetFromExclusionLine( final String line )
     {
         final Set<String> result = new HashSet<>();
         for ( final String className : line.split( "," ) )
         {
             result.add( className.trim() );
         }
         return result;
     }
 
     @Override
     public int countExclusions()
     {
         return exclusionList.size();
     }
 }