/*
 *  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 org.exist.dom.QName;
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.StringValue;
import org.exist.xquery.value.Type;
import org.exist.xquery.value.ValueSequence;

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

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

	public final static FunctionSignature signature =
		new FunctionSignature(
			new QName("escidoc-get-containerid", MPDLDocModule.NAMESPACE_URI, MPDLDocModule.PREFIX),
			"A function which delivers the container id of the first argument: existId." +
			"Second argument is the cookieId.",
			new SequenceType[] { 
        new SequenceType(Type.STRING, Cardinality.EXACTLY_ONE),
			  new SequenceType(Type.STRING, Cardinality.EXACTLY_ONE)
			  },
			new SequenceType(Type.STRING, Cardinality.EXACTLY_ONE));

	public GetESciDocContainerIdByExistId(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 existId = null;
      if (! firstSeqStrValue.equals(""))
        existId = firstSeqStrValue;
      String secondSeqStrValue = secondSeq.getStringValue();
      String eSciDocCookieId = null;
      if (! secondSeqStrValue.equals(""))
        eSciDocCookieId = secondSeqStrValue;
      ESciDocRestSession eSciDocSession = ESciDocRestSession.getInstance(eSciDocCookieId);
      String eScidDocContainerId = eSciDocSession.getContainerIdByEXistId(existId);
      ValueSequence result = new ValueSequence();
      if (eScidDocContainerId != null) {
        result.add(new StringValue(eScidDocContainerId));
      } else {
        result.add(new StringValue(""));
      }
      return result;
	  } catch (ApplicationException e) {
	    throw new XPathException(e);
	  }
	}
	
}