/*
 *  eXist Open Source Native XML Database: Extension module
 *  Copyright (C) 2008 Josef Willenborg
 *  jwillenborg@mpiwg-berlin.mpg.de
 *  http://www.mpiwg-berlin.mpg.de
 *  
 *  This program 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 program 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 program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *  
 *  $Id: TextModule.java $
 */
package org.exist.xquery.modules.mpdldoc;

import java.util.ArrayList;

import org.exist.dom.QName;
import org.exist.memtree.DocumentImpl;
import org.exist.memtree.MemTreeBuilder;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.Type;

import de.mpg.mpiwg.berlin.mpdl.escidoc.ESciDocRestSession;
import de.mpg.mpiwg.berlin.mpdl.exception.ApplicationException;
import de.mpg.mpiwg.berlin.mpdl.general.MpdlConstants;

/**
 * @author Josef Willenborg (jwillenborg@mpiwg-berlin.mpg.de)
 */
public class GetESciDocs extends BasicFunction {

	public final static FunctionSignature signature =
		new FunctionSignature(
			new QName("escidoc-get-docs", MPDLDocModule.NAMESPACE_URI, MPDLDocModule.PREFIX),
			"A function which delivers all eSciDoc documents restricted to the first argument: docbase." +
			"Second argument is the cookieId.",
			new SequenceType[] { 
        new SequenceType(Type.STRING, Cardinality.EXACTLY_ONE),
			  new SequenceType(Type.STRING, Cardinality.EXACTLY_ONE)
			  },
			new SequenceType(Type.NODE, Cardinality.EXACTLY_ONE));

	public GetESciDocs(XQueryContext context) {
		super(context, signature);
	}

	public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException {
	  try {
      Sequence firstSeq = args[0];
      Sequence secondSeq = args[1];
      if (firstSeq.isEmpty() || secondSeq.isEmpty())
        return Sequence.EMPTY_SEQUENCE;
      String firstSeqStrValue = firstSeq.getStringValue();
      String docBase = null;
      if (! firstSeqStrValue.equals(""))
        docBase = firstSeqStrValue;
      String docBaseContainerId = MpdlConstants.MPDL_ESCIDOC_ECHO_CONTAINER_ID;
      if (docBase != null && docBase.equals("archimedes"))
        docBaseContainerId = MpdlConstants.MPDL_ESCIDOC_ARCHIMEDES_CONTAINER_ID;
      String secondSeqStrValue = secondSeq.getStringValue();
      String eSciDocCookieId = null;
      if (! secondSeqStrValue.equals(""))
        eSciDocCookieId = secondSeqStrValue;
      ESciDocRestSession eSciDocSession = ESciDocRestSession.getInstance(eSciDocCookieId);
      String containerXmlStr = eSciDocSession.getContainer(docBaseContainerId);
      ArrayList<String> containerIdsOfDocBaseContainer = eSciDocSession.getContainerIds(containerXmlStr);
      ArrayList<String> containerTitlesOfDocBaseContainer = eSciDocSession.getContainerTitles(containerXmlStr);
      DocumentImpl doc = null;
      if (containerIdsOfDocBaseContainer != null) {
        MemTreeBuilder builder = context.getDocumentBuilder();
        builder.startElement("", "documents", "documents", null);
        for (int i=0; i<containerIdsOfDocBaseContainer.size(); i++) {
          builder.startElement("", "doc", "doc", null);
          builder.startElement("", "container-id", "container-id", null);
          String containerId = containerIdsOfDocBaseContainer.get(i);
          builder.characters(containerId);
          builder.endElement();
          builder.startElement("", "exist-id", "exist-id", null);
          String containerTitle = containerTitlesOfDocBaseContainer.get(i);
          String existId = "";
          if (containerTitle != null) {
            int beginIndex = containerTitle.indexOf("document-id:");
            int endIndex = containerTitle.indexOf(".xml", beginIndex);
            if (beginIndex > 0 && endIndex > 0) {
              existId = containerTitle.substring(beginIndex + 13, endIndex + 4);
              builder.characters(existId);
            }
          }
          builder.endElement();
          builder.endElement();
        }
        builder.endElement();
        doc = ((DocumentImpl)builder.getDocument());
      } else {
        return Sequence.EMPTY_SEQUENCE;
      }
      return doc;
	  } catch (ApplicationException e) {
	    throw new XPathException(e);
	  }
	}
	
}