/**

  * 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.

  */

 package org.apache.creadur.whisker.app.analysis;

 import java.util.ArrayList;

 import java.util.Collection;

 import java.util.TreeSet;

 import org.apache.commons.lang3.tuple.ImmutablePair;

 import org.apache.commons.lang3.tuple.Pair;

 import org.apache.creadur.whisker.model.Resource;

 import org.apache.creadur.whisker.model.Visitor;

 import org.apache.creadur.whisker.model.WithLicense;

 import org.apache.creadur.whisker.model.WithinDirectory;

 /**

  * Collects resource source details.

  */

 public final class ResourceSourceAuditor extends Visitor {

     /** Last license visited. */

     private WithLicense lastLicense;

     /** Last directory visited. */

     private WithinDirectory lastDirectory;

     /** Collects resources that are missing source. */

     private final Collection<

         Pair<WithinDirectory, Resource>> resourcesMissingSource

             = new TreeSet<Pair<WithinDirectory, Resource>>();

     /** Collects resources that match a source. */

     private final Collection<

         Pair<WithinDirectory, Resource>> resourcesWithSource

             = new TreeSet<Pair<WithinDirectory, Resource>>();

     /**

      * Hook for public domain.

      * @return false (no need to traverse public domain)

      * @see Visitor#traversePublicDomain()

      */

     @Override

     public boolean traversePublicDomain() {

         // no need to traverse public domain

         return false;

     }

     /**

      * Gets the resources with source collected during visits.

      * @return the resourcesWithSource, not null

      */

     public Collection<

             Pair<WithinDirectory, Resource>> getResourcesWithSource() {

         return resourcesWithSource;

     }

     /**

      * Gets the resources missing source collected during visits.

      * @return the resourcesMissingSource not null

      */

     public Collection<

             Pair<WithinDirectory, Resource>> getResourcesMissingSource() {

         return resourcesMissingSource;

     }

     /**

      * Accepts a directory visit.

      * @param directory not null

      * @see Visitor#visit(WithinDirectory)

      */

     @Override

     public void visit(final WithinDirectory directory) {

         this.lastDirectory = directory;

     }

     /**

      * Accepts a license visit.

      * @param license not null

      * @see Visitor#visit(WithLicense)

      */

     @Override

     public void visit(final WithLicense license) {

         this.lastLicense = license;

     }

     /**

      * Accepts a visit to a resource.

      * @param resource not null

      * @see Visitor#visit(Resource)

      */

     @Override

     @SuppressWarnings("PMD.EmptyIfStmt")

     public void visit(final Resource resource) {

         if (lastLicense == null) {

             throw new IllegalArgumentException(

                     "Last license unexpectedly null for resource "

                             + resource);

         } else if (lastLicense.isSourceRequired()) {

             final ImmutablePair<WithinDirectory, Resource> pair =

                     new ImmutablePair<

                         WithinDirectory,

                         Resource>(lastDirectory, resource);

             if (resource.hasSource()) {

                 resourcesWithSource.add(pair);

             } else {

                 resourcesMissingSource.add(pair);

             }

         } else {

             // Source not required

         }

     }

     /**

      * Gets those resources visited which require source links.

      * @return not null, possibly empty

      */

     public Collection<Resource> getResourcesRequiringSourceLinks() {

         final Collection<Resource> results = new ArrayList<Resource>();

         for (Pair<WithinDirectory, Resource> pair: resourcesWithSource) {

             results.add(pair.getRight());

         }

         return results;

     }

 }