/**
 * $RCSfile$
 * $Revision: 7071 $
 * $Date: 2007-02-11 18:59:05 -0600 (Sun, 11 Feb 2007) $
 *
 * Copyright 2003-2007 Jive Software.
 *
 * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.jivesoftware.smackx.provider;

import java.util.ArrayList;

import org.jivesoftware.smack.packet.PacketExtension;
import org.jivesoftware.smack.provider.PacketExtensionProvider;
import org.jivesoftware.smackx.RemoteRosterEntry;
import org.jivesoftware.smackx.packet.RosterExchange;
import org.xmlpull.v1.XmlPullParser;

/**
 * 
 * The RosterExchangeProvider parses RosterExchange packets.
 * 
 * @author Gaston Dombiak
 */
public class RosterExchangeProvider implements PacketExtensionProvider {

	/**
	 * Creates a new RosterExchangeProvider. ProviderManager requires that every
	 * PacketExtensionProvider has a public, no-argument constructor
	 */
	public RosterExchangeProvider() {
	}

	/**
	 * Parses a RosterExchange packet (extension sub-packet).
	 * 
	 * @param parser
	 *            the XML parser, positioned at the starting element of the
	 *            extension.
	 * @return a PacketExtension.
	 * @throws Exception
	 *             if a parsing error occurs.
	 */
	@Override
	public PacketExtension parseExtension(XmlPullParser parser)
			throws Exception {

		final RosterExchange rosterExchange = new RosterExchange();
		boolean done = false;
		RemoteRosterEntry remoteRosterEntry = null;
		String jid = "";
		String name = "";
		ArrayList<String> groupsName = new ArrayList<String>();
		while (!done) {
			final int eventType = parser.next();
			if (eventType == XmlPullParser.START_TAG) {
				if (parser.getName().equals("item")) {
					// Reset this variable since they are optional for each item
					groupsName = new ArrayList<String>();
					// Initialize the variables from the parsed XML
					jid = parser.getAttributeValue("", "jid");
					name = parser.getAttributeValue("", "name");
				}
				if (parser.getName().equals("group")) {
					groupsName.add(parser.nextText());
				}
			} else if (eventType == XmlPullParser.END_TAG) {
				if (parser.getName().equals("item")) {
					// Create packet.
					remoteRosterEntry = new RemoteRosterEntry(jid, name,
							groupsName.toArray(new String[groupsName.size()]));
					rosterExchange.addRosterEntry(remoteRosterEntry);
				}
				if (parser.getName().equals("x")) {
					done = true;
				}
			}
		}

		return rosterExchange;

	}

}