// BSD License (http://www.galagosearch.org/license)

 package org.galagosearch.core.parse;

 import java.io.IOException;

 import org.galagosearch.core.types.AdditionalDocumentText;

 import org.galagosearch.tupleflow.InputClass;

 import org.galagosearch.tupleflow.OutputClass;

 import org.galagosearch.tupleflow.StandardStep;

 import org.galagosearch.tupleflow.TupleFlowParameters;

 import org.galagosearch.tupleflow.TypeReader;

 import org.galagosearch.tupleflow.Utility;

 import org.galagosearch.tupleflow.execution.ErrorHandler;

 import org.galagosearch.tupleflow.execution.Verification;

 /**

  * Adds tuples of type AdditionalDocumentText to the end of the text field in

  * a document.  The AdditionalDocumentText stream is specified in the

  * textSource parameter.  This stage should be used before document tokenizing.

  * 

  * @author trevor

  */

 @InputClass(className = "org.galagosearch.core.parse.Document")

 @OutputClass(className = "org.galagosearch.core.parse.Document")

 public class AdditionalTextCombiner extends StandardStep<Document, Document> {

     TypeReader<AdditionalDocumentText> text;

     AdditionalDocumentText last;

     @SuppressWarnings("unchecked")

     public AdditionalTextCombiner(TupleFlowParameters parameters) throws IOException {

         String readerName = parameters.getXML().get("textSource");

         text = parameters.getTypeReader(readerName);

         last = text.read();

     }

     public static void verify(TupleFlowParameters parameters, ErrorHandler handler) {

         if (!Verification.requireParameters(new String[] { "textSource" }, parameters.getXML(), handler))

             return;

         String readerName = parameters.getXML().get("textSource");

         Verification.verifyTypeReader(readerName, AdditionalDocumentText.class, parameters, handler);

     }

     @Override

     public void process(Document document) throws IOException {

         while (last != null && Utility.compare(last.identifier, document.identifier) < 0) {

             last = text.read();

         }

         if (last != null && last.identifier.equals(document.identifier)) {

             document.text += last.text;

         }

         processor.process(document);

     }

 }