/**
 * @RDE_HEADER@
 * plugin loader helper function
 * $Id$
 * $HeadURL$
 * $Author$
 *
 * Created by Christian Ehrlicher, SLSE, 2016-07-07
 */

#pragma once

#define PLUGIN_LOADER_VERSION 3

#include <qglobal.h>
#include <functional>
#include <QMap>
#include <QPair>

#ifndef LTSPLUGINLOADER_EXPORT
# ifdef BUILD_STATIC_LIBRARIES
#  define LTSPLUGINLOADER_EXPORT
# else
#  if defined(MAKE_LTSPLUGINLOADER_LIB)
#   define LTSPLUGINLOADER_EXPORT Q_DECL_EXPORT
#  else
#   define LTSPLUGINLOADER_EXPORT Q_DECL_IMPORT
#  endif
# endif
#endif

class QObject;
class QPluginLoader;

namespace LtsAppDescriptor
{
struct AppDescription;
}

namespace LtsPluginManager
{

enum class PluginType
{
  UNKNOWN = 0, // should not happen
  DATA, // 1
  GUI, // 2
  TOPIC_TYPE,
  PROJECT,
  STYLE,
  SPECIAL, // TODO: rm
  GUI_ELEMENT,

};


struct PluginInstance // one instance for one plugin
{
  QString pluginName;
  QString fullFileName;
  QString fileName;
  QObject *plugin = nullptr;
  QPluginLoader *pluginLoader = nullptr;
};


class LTSPLUGINLOADER_EXPORT LtsPluginLoader
{
public:
  static LtsPluginLoader *getInstance();

  void unloadAllPlugins();

  void checkPlugins(const QVector<LtsAppDescriptor::AppDescription> &appVector,
                    QStringList &errors /* out */);

  bool loadPlugins(PluginType requestedPluginType,
                   const std::function<bool(const PluginInstance &pluginInstance)> &loadPlugin,
                   const QStringList &requiredPlugins = QStringList(), /* leave empty to get all plugins of the given type */
                   const QString &specialTopicTypeFilter = QString(),
                   const QStringList &optionalPlugins = QStringList());

  typedef QPair<PluginType, QString> PluginKey;

private:
  friend struct LtsPluginLoaderHandler;

  LtsPluginLoader() = default;
  ~LtsPluginLoader();

  QMap<PluginKey, PluginInstance> m_loadedPlugins; // TODO: meh...
};

} // namespace LtsPluginManager