/*
 *                    BioJava development code
 *
 * This code may be freely distributed and modified under the
 * terms of the GNU Lesser General Public Licence.  This should
 * be distributed with the code.  If you do not have a copy,
 * see:
 *
 *      http://www.gnu.org/copyleft/lesser.html
 *
 * Copyright for this code is held jointly by the individual
 * authors.  These should be listed in @author doc comments.
 *
 * For more information on the BioJava project and its aims,
 * or to join the biojava-l mailing list, visit the home page
 * at:
 *
 *      http://www.biojava.org/
 *
 */
package org.biojava.nbio.structure.align.xml;

import org.biojava.nbio.core.util.PrettyXMLWriter;
import org.w3c.dom.Document;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.SortedSet;
import java.util.TreeSet;

public class RepresentativeXMLConverter {


	public static final String toXML(SortedSet<String> representatives){
		StringWriter sw = new StringWriter();
		PrintWriter writer = new PrintWriter(sw);

		PrettyXMLWriter xml = new PrettyXMLWriter(writer);
		try {
			xml.openTag("representatives");

			for ( String repr : representatives){
				xml.openTag("pdbChain");
				xml.attribute("name", repr);
				xml.closeTag("pdbChain");
			}
			xml.closeTag("representatives");
		} catch(IOException ex){
			ex.printStackTrace();
		}
		return sw.toString();
	}

	public static final SortedSet<String> fromXML(String xml){
		SortedSet<String> representatives = new TreeSet<String>();
		try {
			DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
			DocumentBuilder db = factory.newDocumentBuilder();
			InputSource inStream = new InputSource();
			inStream.setCharacterStream(new StringReader(xml));
			Document doc = db.parse(inStream);

			// normalize text representation
			doc.getDocumentElement().normalize();


			//Element rootElement = doc.getDocumentElement();

			NodeList listOfPairs = doc.getElementsByTagName("pdbChain");
			//int numArrays = listOfArrays.getLength();

			// go over the blocks
			for(int i=0; i<listOfPairs.getLength() ; i++)
			{
				Node pair       = listOfPairs.item(i);
				//NodeList valList = pair.getChildNodes();
				//int numChildren  = valList.getLength();

				NamedNodeMap map = pair.getAttributes();

				String name =  map.getNamedItem("name").getTextContent();
				representatives.add(name);
			}

		} catch (Exception e){
			e.printStackTrace();
		}

		return representatives;
	}
}