package org.apache.maven.shared.artifact.filter.collection;
   
   /* 
    * 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.Arrays;
  import java.util.LinkedHashSet;
  import java.util.List;
  import java.util.Objects;
  import java.util.Set;
  
  import org.apache.maven.artifact.Artifact;
  
  import static org.apache.maven.shared.artifact.filter.internal.Utils.isNotEmpty;
  
  /**
   * This is the common base class of ClassifierFilter and TypeFilter
   *
   * @author <a href="richardv@mxtelecom.com">Richard van der Hoff</a>
   */
  public abstract class AbstractArtifactFeatureFilter
      extends AbstractArtifactsFilter
  {
      /** The list of types or classifiers to include */
      private List<String> includes;
  
      /**
       * The list of types or classifiers to exclude (ignored if includes != null)
       */
      private List<String> excludes;
  
      /**
       * <p>Constructor for AbstractArtifactFeatureFilter.</p>
       *
       * @param include comma separated list with includes.
       * @param exclude comma separated list with excludes.
       */
      public AbstractArtifactFeatureFilter( String include, String exclude )
      {
          setExcludes( exclude );
          setIncludes( include );
      }
  
      /**
       * {@inheritDoc}
       *
       * This function determines if filtering needs to be performed. Includes are processed before Excludes.
       */
      public Set<Artifact> filter( Set<Artifact> artifacts )
      {
          Set<Artifact> results = artifacts;
  
          if ( this.includes != null && !this.includes.isEmpty() )
          {
              results = filterIncludes( results, this.includes );
          }
  
          if ( this.excludes != null && !this.excludes.isEmpty() )
          {
              results = filterExcludes( results, this.excludes );
          }
  
          return results;
      }
  
      /**
       * Processes the dependencies list and includes the dependencies that match a filter in the list.
       * 
       * @param artifacts List of dependencies.
       * @param theIncludes List of types or classifiers to include.
       * @return a set of filtered artifacts.
       */
      private Set<Artifact> filterIncludes( Set<Artifact> artifacts, List<String> theIncludes )
      {
          Set<Artifact> result = new LinkedHashSet<>();
  
          for ( String include : theIncludes )
          {
              for ( Artifact artifact : artifacts )
              {
                  // if the classifier or type of the artifact
                  // matches the feature
                  // to include, add to the
                 // results
                 if ( compareFeatures( getArtifactFeature( artifact ), include ) )
                 {
                     result.add( artifact );
                 }
             }
         }
         return result;
     }
 
     /**
      * Processes the dependencies list and excludes the dependencies that match a filter in the list.
      * 
      * @param artifacts List of dependencies.
      * @param theExcludes List of types or classifiers to exclude.
      * @return a set of filtered artifacts.
      */
     private Set<Artifact> filterExcludes( Set<Artifact> artifacts, List<String> theExcludes )
     {
         Set<Artifact> result = new LinkedHashSet<>();
 
         for ( Artifact artifact : artifacts )
         {
             boolean exclude = false;
             String artifactFeature = getArtifactFeature( artifact );
 
             // look through all types or classifiers. If no
             // matches are found
             // then it can be added to the results.
             for ( String excludeFeature : theExcludes )
             {
                 if ( compareFeatures( artifactFeature, excludeFeature ) )
                 {
                     exclude = true;
                     break;
                 }
             }
 
             if ( !exclude )
             {
                 result.add( artifact );
             }
         }
 
         return result;
     }
 
     /**
      * Should return the type or classifier of the given artifact, so that we can filter it
      *
      * @param artifact artifact to return type or classifier of
      * @return type or classifier
      */
     protected abstract String getArtifactFeature( Artifact artifact );
 
     /**
      * <p>Setter for the field <code>excludes</code>.</p>
      *
      * @param excludeString comma separated list with excludes.
      */
     public void setExcludes( String excludeString )
     {
         if ( isNotEmpty( excludeString ) )
         {
             this.excludes = Arrays.asList( excludeString.split( "," ) );
         }
     }
 
     /**
      * <p>Setter for the field <code>includes</code>.</p>
      *
      * @param includeString comma separated list with includes.
      */
     public void setIncludes( String includeString )
     {
         if ( isNotEmpty( includeString ) )
         {
             this.includes = Arrays.asList( includeString.split( "," ) );
         }
     }
 
     /**
      * <p>Getter for the field <code>excludes</code>.</p>
      *
      * @return Returns the excludes.
      */
     public List<String> getExcludes()
     {
         return this.excludes;
     }
 
     /**
      * <p>Getter for the field <code>includes</code>.</p>
      *
      * @return Returns the includes.
      */
     public List<String> getIncludes()
     {
         return this.includes;
     }
 
     /**
      * Allows Feature comparison to be customized
      *
      * @param lhs String artifact's feature
      * @param rhs String feature from exclude or include list
      * @return boolean true if features match
      */
     protected boolean compareFeatures( String lhs, String rhs )
     {
         return ( Objects.equals( lhs, rhs ) );
     }
 }