/**
 * 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.search;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;

import org.jivesoftware.smack.Connection;
import org.jivesoftware.smack.XMPPException;
import org.jivesoftware.smackx.Form;
import org.jivesoftware.smackx.ReportedData;
import org.jivesoftware.smackx.ServiceDiscoveryManager;
import org.jivesoftware.smackx.packet.DiscoverInfo;
import org.jivesoftware.smackx.packet.DiscoverItems;

/**
 * The UserSearchManager is a facade built upon Jabber Search Services (JEP-055)
 * to allow for searching repositories on a Jabber Server. This implementation
 * allows for transparency of implementation of searching (DataForms or No
 * DataForms), but allows the user to simply use the DataForm model for both
 * types of support.
 * 
 * <pre>
 * Connection con = new XMPPConnection("jabber.org");
 * con.login("john", "doe");
 * UserSearchManager search = new UserSearchManager(con, "users.jabber.org");
 * Form searchForm = search.getSearchForm();
 * Form answerForm = searchForm.createAnswerForm();
 * answerForm.setAnswer("last", "DeMoro");
 * ReportedData data = search.getSearchResults(answerForm);
 * // Use Returned Data
 * </pre>
 * 
 * @author Derek DeMoro
 */
public class UserSearchManager {

	private final Connection con;
	private final UserSearch userSearch;

	/**
	 * Creates a new UserSearchManager.
	 * 
	 * @param con
	 *            the Connection to use.
	 */
	public UserSearchManager(Connection con) {
		this.con = con;
		userSearch = new UserSearch();
	}

	/**
	 * Returns the form to fill out to perform a search.
	 * 
	 * @param searchService
	 *            the search service to query.
	 * @return the form to fill out to perform a search.
	 * @throws XMPPException
	 *             thrown if a server error has occurred.
	 */
	public Form getSearchForm(String searchService) throws XMPPException {
		return userSearch.getSearchForm(con, searchService);
	}

	/**
	 * Submits a search form to the server and returns the resulting information
	 * in the form of <code>ReportedData</code>
	 * 
	 * @param searchForm
	 *            the <code>Form</code> to submit for searching.
	 * @param searchService
	 *            the name of the search service to use.
	 * @return the ReportedData returned by the server.
	 * @throws XMPPException
	 *             thrown if a server error has occurred.
	 */
	public ReportedData getSearchResults(Form searchForm, String searchService)
			throws XMPPException {
		return userSearch.sendSearchForm(con, searchForm, searchService);
	}

	/**
	 * Returns a collection of search services found on the server.
	 * 
	 * @return a Collection of search services found on the server.
	 * @throws XMPPException
	 *             thrown if a server error has occurred.
	 */
	public Collection<String> getSearchServices() throws XMPPException {
		final List<String> searchServices = new ArrayList<String>();
		final ServiceDiscoveryManager discoManager = ServiceDiscoveryManager
				.getInstanceFor(con);
		final DiscoverItems items = discoManager.discoverItems(con
				.getServiceName());
		final Iterator<DiscoverItems.Item> iter = items.getItems();
		while (iter.hasNext()) {
			final DiscoverItems.Item item = iter.next();
			try {
				DiscoverInfo info;
				try {
					info = discoManager.discoverInfo(item.getEntityID());
				} catch (final XMPPException e) {
					// Ignore Case
					continue;
				}

				if (info.containsFeature("jabber:iq:search")) {
					searchServices.add(item.getEntityID());
				}
			} catch (final Exception e) {
				// No info found.
				break;
			}
		}
		return searchServices;
	}
}