/* This file is part of the KDE project
   Copyright (C) 1999 Simon Hausmann <hausmann@kde.org>
             (C) 1999 David Faure <faure@kde.org>

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.

   This library 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public License
   along with this library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.
*/
#ifndef PLUGIN_H
#define PLUGIN_H

#include <qobject.h>
#include <kaction.h>
#include <kxmlgui.h>
#include <kxmlguiclient.h>

class KInstance;

namespace KParts
{

/**
 * A plugin is the way to add actions to an existing @ref KParts application,
 * or to a @ref Part.
 *
 * The XML of those plugins looks exactly like of the shell or parts,
 * with one small difference: The document tag should have an additional
 * attribute, named "library", and contain the name of the library implementing
 * the plugin.
 *
 * If you want this plugin to be used by a part, you need to
 * install the rc file under the directory
 * "data" (KDEDIR/share/apps usually)+"/instancename/kpartplugins/"
 * where instancename is the name of the part's instance.
 **/
class Plugin : public QObject, virtual public KXMLGUIClient
{
    Q_OBJECT
public:
    struct PluginInfo
    {
        QString m_relXMLFileName; // relative filename, i.e. instanceName/kpartplugins/name
        QString m_absXMLFileName; // full path of most recent filename matching the relative
                                  // filename
        QDomDocument m_document;
    };

    /**
     * Construct a new KParts plugin.
     */
    Plugin( QObject* parent = 0, const char* name = 0 );
    /**
     * Destructor.
     */
    virtual ~Plugin();

    /**
     * Load the plugin libraries from the directories appropriate
     * to @p instance and make the @ref Plugin objects children of @p parent .
     */
    static void loadPlugins( QObject *parent, const KInstance * instance );

    /**
     * Load the plugin libraries specified by the list @p docs and make the
     * Plugin objects children of @p parent .
     */
    static void loadPlugins( QObject *parent, const QValueList<PluginInfo> &pluginInfos );

    /**
     * Returns a list of plugin objects loaded for @p parent. This
     * functions basically calls the @ref queryList method of @ref
     * QObject to retrieve the list of child objects inheritting @ref
     * KParts::Plugin .
     **/
    static QList<Plugin> pluginObjects( QObject *parent );

protected:
    /**
     * Look for plugins in the @p instance's "data" directory (+"/kpartplugins")
     *
     * @return A list of @ref QDomDocument s, containing the parsed xml documents returned by plugins.
     */
    static QValueList<Plugin::PluginInfo> pluginInfos( const KInstance * instance );

    /**
     * @internal
     * @return The plugin created from the library @p libname
     */
    static Plugin* loadPlugin( QObject * parent, const char* libname );

private:
    class PluginPrivate;
    PluginPrivate *d;
};

};

#endif
