/*
    * Copyright 2008-2010 Digital Enterprise Research Institute (DERI)
    *
    * Licensed 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.deri.any23.extractor.html;
  
  import org.deri.any23.extractor.ExtractionResult;
  import org.deri.any23.extractor.ExtractorDescription;
  import org.deri.any23.extractor.ExtractorFactory;
  import org.deri.any23.extractor.SimpleExtractorFactory;
  import org.deri.any23.extractor.TagSoupExtractionResult;
  import org.deri.any23.rdf.PopularPrefixes;
  import org.deri.any23.vocab.VCARD;
  import org.openrdf.model.BNode;
  import org.openrdf.model.vocabulary.RDF;
  import org.w3c.dom.Node;
  
  import java.util.Arrays;
  
  import static org.deri.any23.extractor.html.HTMLDocument.TextField;
  
  
  /**
   * Extractor for the <a href="http://microformats.org/wiki/geo">Geo</a>
   * microformat.
   *
   * @author Gabriele Renzi
   */
  public class GeoExtractor extends EntityBasedMicroformatExtractor {
  
      private static final VCARD vVCARD = VCARD.getInstance();
  
      public static final ExtractorFactory<GeoExtractor> factory =
              SimpleExtractorFactory.create(
                  "html-mf-geo",
                  PopularPrefixes.createSubset("rdf", "vcard"),
                  Arrays.asList("text/html;q=0.1", "application/xhtml+xml;q=0.1"),
                  null,
                  GeoExtractor.class
              );
  
      public ExtractorDescription getDescription() {
          return factory;
      }
  
      protected String getBaseClassName() {
          return "geo";
      }
  
      @Override
      protected void resetExtractor() {
          // Empty.
      }
  
      protected boolean extractEntity(Node node, ExtractionResult out) {
          if (null == node) return false;
          //try lat & lon
          final HTMLDocument document = new HTMLDocument(node);
          HTMLDocument.TextField latNode = document.getSingularTextField("latitude" );
          TextField lonNode = document.getSingularTextField("longitude");
          String lat = latNode.value();
          String lon = lonNode.value();
          if ("".equals(lat) || "".equals(lon)) {
              String[] both = document.getSingularUrlField("geo").value().split(";");
              if (both.length != 2) return false;
              lat = both[0];
              lon = both[1];
          }
          BNode geo = getBlankNodeFor(node);
          out.writeTriple(geo, RDF.TYPE, vVCARD.Location);
          final String extractorName = getDescription().getExtractorName();
          conditionallyAddStringProperty(
                  latNode.source(),
                  geo, vVCARD.latitude , lat
          );
          conditionallyAddStringProperty(
                  lonNode.source(),
                  geo, vVCARD.longitude, lon
          );
  
          final TagSoupExtractionResult tser = (TagSoupExtractionResult) getCurrentExtractionResult();
          tser.addResourceRoot( document.getPathToLocalRoot(), geo, this.getClass() );
  
          return true;
      }
      
  }