//
// A Plugin system for FLTK, implemented in Fl_Preferences.cxx.
//
// Copyright 2002-2023 by Matthias Melcher.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file.  If this
// file is missing or damaged, see the license at:
//
//     https://www.fltk.org/COPYING.php
//
// Please see the following page on how to report bugs and issues:
//
//     https://www.fltk.org/bugs.php
//

/* \file
   Fl_Plugin class . */

#ifndef Fl_Plugin_H
#  define Fl_Plugin_H

#  include "Fl_Preferences.H"


/**
 \brief Fl_Plugin allows link-time and run-time integration of binary modules.

 Fl_Plugin and Fl_Plugin_Manager provide a small and simple solution for
 linking C++ classes at run-time, or optionally linking modules at compile
 time without the need to change the main application.

 Fl_Plugin_Manager uses static initialization to create the plugin interface
 early during startup. Plugins are stored in a temporary database, organized
 in classes.

 Plugins should derive a new class from Fl_Plugin as a base:
 \code
 class My_Plugin : public Fl_Plugin {
 public:
   My_Plugin() : Fl_Plugin("effects", "blur") { }
   void do_something(...);
 };
 My_Plugin blur_plugin();
 \endcode

 Plugins can be put into modules and either linked before distribution, or loaded
 from dynamically linkable files. An Fl_Plugin_Manager is used to list and
 access all currently loaded plugins.
 \code
 Fl_Plugin_Manager mgr("effects");
 int i, n = mgr.plugins();
 for (i=0; i<n; i++) {
   My_Plugin *pin = (My_Plugin*)mgr.plugin(i);
   pin->do_something();
 }
 \endcode
 */
class FL_EXPORT Fl_Plugin  {
  Fl_Preferences::ID id;
public:
  Fl_Plugin(const char *klass, const char *name);
  virtual ~Fl_Plugin();
};


/**
 \brief Fl_Plugin_Manager manages link-time and run-time plugin binaries.
 \see Fl_Plugin
 */
class FL_EXPORT Fl_Plugin_Manager : public Fl_Preferences {
public:
  Fl_Plugin_Manager(const char *klass);
  ~Fl_Plugin_Manager();

  /** \brief Return the number of plugins in the klass.
   */
  int plugins() { return groups(); }
  Fl_Plugin *plugin(int index);
  Fl_Plugin *plugin(const char *name);
  Fl_Preferences::ID addPlugin(const char *name, Fl_Plugin *plugin);

  static void removePlugin(Fl_Preferences::ID id);
  static int load(const char *filename);
  static int loadAll(const char *dirpath, const char *pattern=0);
};


#endif // !Fl_Preferences_H