/**************************************************************************
/* Render a document with a text-only header. The document must follow
/* the StandardDocument standard.
/*
/* Copyright (c) 2003-2004 by Bernhard Bablok (mail@bablokb.de)
/*
/* This library is free software; you can redistribute it and/or modify
/* it under the terms of the GNU Lesser General Public License as published
/* by  the Free Software Foundation; either version 2 of the License or
/* (at your option) any later version.
/*
/* This library is distributed in the hope that it will be useful, but
/* WITHOUT ANY WARRANTY; without even the implied warranty of
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
/* GNU Lesser General Public License for more details.
/*
/* You should have received a copy of the GNU Lesser General Public License
/* along with this library; see the file COPYING.LESSER.  If not, write to
/* the Free Software Foundation Inc., 59 Temple Place - Suite 330,
/* Boston, MA  02111-1307 USA
/**************************************************************************/

package de.bablokb.luala.lib;

import java.io.*;
import java.util.*;
import org.apache.lucene.document.*;

/**
   Render a document with text-only header. The document must follow
   the StandardDocument standard.

   @see StandardDocumentFactory

   @version $Revision: 1.6 $
   @author  $Author: bablokb $
*/

public class StandardDocumentTextRenderer extends StandardDocumentRenderer {

  ////////////////////////////////////////////////////////////////////////////

  /**
     Line length of summary.
  */

  private final static int SUMMARY_LINE_LENGTH = 60;

  ////////////////////////////////////////////////////////////////////////////

  /**
     Counter for the sequence of hits.
  */

  private int iCounter = 0;

  ////////////////////////////////////////////////////////////////////////////

  /**
     Constructor. This just sets the header and footer fields of the base
     class.
  */

  public StandardDocumentTextRenderer() {
    setFooter("\n");
  }

  ////////////////////////////////////////////////////////////////////////////

  /**
     {@inheritDoc}
  */

  public synchronized String render(Document doc)
                                  throws IOException, IllegalStateException {
    iCounter++;
    setHeader(iCounter+": ");
    return super.render(doc);
  }

  ////////////////////////////////////////////////////////////////////////////

  /**
     This method will render the Summary-field of the document. Implements
     {@link StandardDocumentRenderer#renderSummary}.

     @throws IOException
     @throws IllegalStateException if document contains no SUMMARY-field
  */

  public String renderSummary(Document doc)
                                   throws IOException, IllegalStateException {
    String summary = doc.get(DocumentFactory.SUMMARY);
    if (summary == null)
      throw new IllegalStateException("error: missing " + 
        DocumentFactory.SUMMARY + "-field in document!");
    
    StringBuffer buffer = new StringBuffer(summary.length());
    buffer.append('\n');
    StringTokenizer tokenizer = new StringTokenizer(summary," \t\n\r\f",true);
    StringBuffer line = new StringBuffer(SUMMARY_LINE_LENGTH);
    while (true) {
      line.setLength(0);
      line.append("\t");
      String token = "";
      while (tokenizer.hasMoreTokens() && line.length() < SUMMARY_LINE_LENGTH) {
	token = tokenizer.nextToken();
	line.append(token);
	if (token.equals("\n"))
	  break;
      }
      buffer.append(line);
	if (!token.equals("\n"))
	  buffer.append('\n');
      if (!tokenizer.hasMoreTokens())
	break;
    }
    return buffer.toString();
  }

}