source: trunk/jabberit_messenger/java_source/src/nu/fw/jeti/backend/CapabilitiesCache.java @ 1001

/* 
 *      Jeti, a Java Jabber client, Copyright (C) 2007 E.S. de Boer  
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *      For questions, comments etc, 
 *      use the website at http://jeti.jabberstudio.org
 */

//created on Mar 11, 2007
package nu.fw.jeti.backend;

import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.net.URL;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;
import org.xml.sax.helpers.DefaultHandler;

import nu.fw.jeti.events.DiscoveryListener;
import nu.fw.jeti.jabber.Backend;
import nu.fw.jeti.jabber.JID;
import nu.fw.jeti.jabber.elements.DiscoItem;
import nu.fw.jeti.jabber.elements.DiscoveryInfo;
import nu.fw.jeti.jabber.elements.DiscoveryItem;
import nu.fw.jeti.jabber.elements.IQDiscoInfo;
import nu.fw.jeti.jabber.elements.IQXCaps;
import nu.fw.jeti.jabber.handlers.IQDiscoInfoHandler;
import nu.fw.jeti.util.Log;
import nu.fw.jeti.util.PreferencesHandler;


public class CapabilitiesCache implements DiscoveryListener {
        private Map capabilities;
        private Map cache;
        private Backend backend;

        
        public CapabilitiesCache(Backend backend)
        {
                this.backend = backend;
                capabilities = new HashMap();
                cache = new HashMap();
        }
        
        public void setCapability(JID jid, IQXCaps caps){
                String cap = caps.getNode() + "#" + caps.getVer();
                addCap(jid, cap);
                if(caps.getExt() != null){
                        String[] extensions = caps.getExt().split(" ");
                        for (int i = 0; i < extensions.length; i++) {
                                cap = caps.getNode() +"#"+ extensions[i];
                                addCap(jid, cap);
                        }
                }
        }

        private void addCap(JID jid, String cap) {
                if(cache.containsKey(cap)){
                        getJIDCapabilities(jid).addCapabilities((IQDiscoInfo)cache.get(cap));
                }
                else {
                        backend.getInfo(jid, cap, this);
                }
        }


        private Capabilities getJIDCapabilities(JID jid) {
                Capabilities jidCapabilities = null;
                if(capabilities.containsKey(jid)){
                        jidCapabilities = (Capabilities) capabilities.get(jid);
                }
                else {
                        jidCapabilities = new Capabilities();
                        capabilities.put(jid,jidCapabilities);
                }
                return jidCapabilities;
        }
        
        public void discoveryInfoResult(JID jid, DiscoveryInfo info){
                if(!info.hasFeatures())return;
                IQDiscoInfo disco = (IQDiscoInfo)info;
                cache.put(disco.getNode(), disco);
                getJIDCapabilities(jid).addCapabilities(disco);
        }
        
        public void discoveryItemResult(JID jid, DiscoveryItem item){}
        
        
        /**
         * Has JID jid capability capability
         * @param jid
         * @param capability
         */
        public boolean hasCapability(JID jid, String capability){
                return getJIDCapabilities(jid).hasCapability(capability);
        }       
        
        public void save()
        {
                StringBuffer xml = new StringBuffer();
                xml.append("<?xml version='1.0'?>");
                xml.append("<queries>");
                for (Iterator iter = cache.values().iterator(); iter.hasNext();) {
                        
                        ((IQDiscoInfo)iter.next()).appendToXML(xml);
                        xml.append("\n");
                }
                xml.append("</queries>");
                System.out.println(xml.toString());
                try
                {
                        BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(
                                        new FileOutputStream(Start.path + "capabilitiesCache.xml"), "UTF8"));
                        writer.write(xml.toString());
                        writer.close();
                }
                catch (IOException ex2)
                {
                        ex2.printStackTrace();
                }
        }
        
        static class DiscoInfoHandler extends DefaultHandler
    {
         private Map queries;
         private IQDiscoInfoHandler discoHandler;
        
        public DiscoInfoHandler(Map queries)
        {
            this.queries = queries;
            discoHandler = new IQDiscoInfoHandler();
        }
            
        public void startElement(String uri, String localName, String qName, Attributes attr) 
        {
                if(qName.equals("queries")); //do nothing top level
                else if(qName.equals("query"))  
            {
                discoHandler.startHandling(attr);
            }
            else discoHandler.startElement(qName, attr);
        }
        
        public void endElement(String uri, String localName, String qName){
                if(qName.equals("query")){
                        IQDiscoInfo info = (IQDiscoInfo) discoHandler.build();
                        queries.put(info.getNode(),info);
                }
        }
        }
        
}