/* 
 *	Jeti, a Java Jabber client, Copyright (C) 2003 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
 *  or mail/IM me at jeti@jabber.org
 *
 *	Created on 26-dec-2003
 */
 
package nu.fw.jeti.plugins;

import java.lang.ref.WeakReference;
import java.lang.reflect.Method;
import java.text.MessageFormat;
import java.util.*;
import javax.xml.parsers.SAXParser;
import nu.fw.jeti.backend.Start;
import nu.fw.jeti.jabber.Backend;
import nu.fw.jeti.util.I18N;
import nu.fw.jeti.util.Preferences;

/**
 * @author E.S. de Boer
 *
 */
public class PluginsInfo
{
	private static Backend backend;
	private static Map loadedPlugins = new HashMap();
	public static Map loadedPreferencePanels = new HashMap();
	private static Map pluginInstances = new HashMap();
	private static String pluginsJava;
			
	public PluginsInfo( Backend backend, Start start )
	{
		PluginsInfo.backend		= backend;
		PluginsInfo.pluginsJava = nu.fw.jeti.applet.Jeti.JAVAPLUGINS;
		
		/**
		 * Carregando plugins:
		 * 
		 * nu.fw.jeti.plugins.<NOME_do_Plugin>.Plugin.init( backend );
		 * loadedPlugins.put("<NOME_do_Plugin>", nu.fw.jeti.plugins.<NOME_do_Plugin>.Plugin.class);
		 * 
		 * Exemplo : Plugin xhtml
		 * nu.fw.jeti.plugins.xhtml.Plugin.init( backend );
		 * loadedPlugins.put("xhtml", nu.fw.jeti.plugins.xhtml.Plugin.class);
		 */
		
		String[] plugins = pluginsJava.split(",");	
		
		for(int i = 0 ; i < plugins.length; i++)
			PluginsInfo.loadPlugin(plugins[i].toString());
	}

	public static boolean isPluginLoaded(String name)
	{
		return loadedPlugins.containsKey(name);
	}

	private static void loadPlugin(String name)
	{
		Class loadedClass = nu.fw.jeti.applet.Jeti.getPlugin(name);
		
		try
		{
			//Init plugin
			Method m = loadedClass.getMethod("init",new Class[]{Backend.class});
			m.invoke(null,new Object[]{backend});
		}
		catch(Exception e)
		{
			e.printStackTrace();
			return;
		}
		
		loadedPlugins.put(name, loadedClass);
	}
	
	public static void unloadPlugin(String name)
	{
		Class loadedClass = (Class)loadedPlugins.remove(name);
        
		if (loadedClass == null)
			return;

        System.out.println(I18N.gettext("main.pluginsInfo.Plugin_removing") + " : " + name);
		
        loadedPreferencePanels.remove(name);
        
		List list = (List) pluginInstances.remove(name);
		
		try
		{
			//unload cleaning
			Method m = loadedClass.getMethod("unload",new Class[]{Backend.class});
			m.invoke(null,new Object[]{backend});
		}
		catch(NoSuchMethodException e)
		{
			System.out.println("ERRO : " + name + " " + I18N.gettext("main.pluginsInfo.has_no_remove"));
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
				
		if ( list == null)
			return;
		
		for (Iterator i = list.iterator(); i.hasNext();)
		{	
			//unload loaded plugins
			Plugins plugin = (Plugins)((WeakReference)i.next()).get();
			
			if ( plugin != null )
				plugin.unload();
		}
		
		System.out.println( "Removed plugin : " + name );
	}
	
	/**
	 * Gets a single instance of a plugin, the plugin has to have the static getInstance() method
	 * @param name name of the plugin
	 * @return instance of the plugin
	 */
	public static Object getPluginInstance(String name)
	{
		Object o = null;
		try
		{
			Class loadedClass = (Class) loadedPlugins.get(name);
			try
			{
				Method m = loadedClass.getMethod("getInstance",null);
				o = m.invoke(null,null);
			}
			catch(NoSuchMethodException e)
			{
				System.out.println(name + " has no instance method");
			}
			catch(Exception e)
			{
				e.printStackTrace();
			}
		}
		catch (Exception ie)
		{
			ie.printStackTrace();
			return null;
		}

		return o;
	}
	
	public static Plugins newPluginInstance(String name)
	{
		Object o = null;
		
		try
		{
			o = ((Class) loadedPlugins.get(name)).newInstance();
			addInstance(name,o);
		}
		catch (Exception ie)
		{
			ie.printStackTrace();
			return null;
		}
		
		return (Plugins) o;
	}

	private static void addInstance(String name, Object object)
	{
		List list = (List) pluginInstances.get(name);
		
		if (list == null)
		{
			list = new LinkedList();
			pluginInstances.put(name, list);
		}
		
		list.add(new WeakReference(object));
	}
	
	public static String getAbout()
	{
		StringBuffer buffer = new StringBuffer();
		
		for(Iterator i = loadedPlugins.entrySet().iterator();i.hasNext();)
		{
			Map.Entry entry = (Map.Entry)i.next();
			String text = null;
			try
			{
				 text = (String) ((Class)entry.getValue()).getField("ABOUT").get(null);
			}
			catch (Exception e1){}
			
			if( text != null)
				buffer.append("\n - " + (String)entry.getKey() + '\n' + text);
		}
		 
		return buffer.toString(); 
	} 
	
	// Remove plugins
	public void exit()
	{
		String[] temp = new String[loadedPlugins.size()];
		loadedPlugins.keySet().toArray(temp);
		
		for(int i=0;i<temp.length;i++)
		{
			unloadPlugin(temp[i]);
		}
		
		System.out.println(I18N.gettext("main.pluginsInfo.plugins_unloaded"));
	}
}

/*
 * Overrides for emacs
 * Local variables:
 * tab-width: 4
 * End:
 */