001/**
002 *
003 * Copyright 2003-2007 Jive Software.
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.jivesoftware.smackx.xhtmlim;
019
020import org.jivesoftware.smack.ConnectionCreationListener;
021import org.jivesoftware.smack.SmackException.NoResponseException;
022import org.jivesoftware.smack.SmackException.NotConnectedException;
023import org.jivesoftware.smack.XMPPConnection;
024import org.jivesoftware.smack.XMPPException.XMPPErrorException;
025import org.jivesoftware.smack.packet.Message;
026import org.jivesoftware.smackx.disco.ServiceDiscoveryManager;
027import org.jivesoftware.smackx.xhtmlim.packet.XHTMLExtension;
028
029import java.util.List;
030
031/**
032 * Manages XHTML formatted texts within messages. A XHTMLManager provides a high level access to 
033 * get and set XHTML bodies to messages, enable and disable XHTML support and check if remote XMPP
034 * clients support XHTML.   
035 * 
036 * @author Gaston Dombiak
037 */
038public class XHTMLManager {
039    private final static String namespace = "http://jabber.org/protocol/xhtml-im";
040
041    // Enable the XHTML support on every established connection
042    // The ServiceDiscoveryManager class should have been already initialized
043    static {
044        XMPPConnection.addConnectionCreationListener(new ConnectionCreationListener() {
045            public void connectionCreated(XMPPConnection connection) {
046                XHTMLManager.setServiceEnabled(connection, true);
047            }
048        });
049    }
050
051    /**
052     * Returns an Iterator for the XHTML bodies in the message. Returns null if 
053     * the message does not contain an XHTML extension.
054     *
055     * @param message an XHTML message
056     * @return an Iterator for the bodies in the message or null if none.
057     */
058    public static List<String> getBodies(Message message) {
059        XHTMLExtension xhtmlExtension = (XHTMLExtension) message.getExtension("html", namespace);
060        if (xhtmlExtension != null)
061            return xhtmlExtension.getBodies();
062        else
063            return null;
064    }
065
066    /**
067     * Adds an XHTML body to the message.
068     *
069     * @param message the message that will receive the XHTML body
070     * @param body the string to add as an XHTML body to the message
071     */
072    public static void addBody(Message message, String body) {
073        XHTMLExtension xhtmlExtension = (XHTMLExtension) message.getExtension("html", namespace);
074        if (xhtmlExtension == null) {
075            // Create an XHTMLExtension and add it to the message
076            xhtmlExtension = new XHTMLExtension();
077            message.addExtension(xhtmlExtension);
078        }
079        // Add the required bodies to the message
080        xhtmlExtension.addBody(body);
081    }
082
083    /**
084     * Returns true if the message contains an XHTML extension.
085     *
086     * @param message the message to check if contains an XHTML extentsion or not
087     * @return a boolean indicating whether the message is an XHTML message
088     */
089    public static boolean isXHTMLMessage(Message message) {
090        return message.getExtension("html", namespace) != null;
091    }
092
093    /**
094     * Enables or disables the XHTML support on a given connection.<p>
095     *  
096     * Before starting to send XHTML messages to a user, check that the user can handle XHTML
097     * messages. Enable the XHTML support to indicate that this client handles XHTML messages.  
098     *
099     * @param connection the connection where the service will be enabled or disabled
100     * @param enabled indicates if the service will be enabled or disabled 
101     */
102    public synchronized static void setServiceEnabled(XMPPConnection connection, boolean enabled) {
103        if (isServiceEnabled(connection) == enabled)
104            return;
105
106        if (enabled) {
107            ServiceDiscoveryManager.getInstanceFor(connection).addFeature(namespace);
108        }
109        else {
110            ServiceDiscoveryManager.getInstanceFor(connection).removeFeature(namespace);
111        }
112    }
113
114    /**
115     * Returns true if the XHTML support is enabled for the given connection.
116     *
117     * @param connection the connection to look for XHTML support
118     * @return a boolean indicating if the XHTML support is enabled for the given connection
119     */
120    public static boolean isServiceEnabled(XMPPConnection connection) {
121        return ServiceDiscoveryManager.getInstanceFor(connection).includesFeature(namespace);
122    }
123
124    /**
125     * Returns true if the specified user handles XHTML messages.
126     *
127     * @param connection the connection to use to perform the service discovery
128     * @param userID the user to check. A fully qualified xmpp ID, e.g. jdoe@example.com
129     * @return a boolean indicating whether the specified user handles XHTML messages
130     * @throws XMPPErrorException 
131     * @throws NoResponseException 
132     * @throws NotConnectedException 
133     */
134    public static boolean isServiceEnabled(XMPPConnection connection, String userID)
135                    throws NoResponseException, XMPPErrorException, NotConnectedException {
136        return ServiceDiscoveryManager.getInstanceFor(connection).supportsFeature(userID, namespace);
137    }
138}