/****************************************************************************
**
** https://www.qxorm.com/
** Copyright (C) 2013 XDL Team (ic-east.com)
**
** This file is part of the QxOrm library
**
** This software is provided 'as-is', without any express or implied
** warranty. In no event will the authors be held liable for any
** damages arising from the use of this software
**
** Commercial Usage
** Licensees holding valid commercial QxOrm licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and XDL Team
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file 'license.gpl3.txt' included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met : http://www.gnu.org/copyleft/gpl.html
**
** If you are unsure which license is appropriate for your use, or
** if you have questions regarding the use of this file, please contact :
** ic-east.com
**
****************************************************************************/

#ifndef _QX_QT_META_OBJECT_H_
#define _QX_QT_META_OBJECT_H_

#ifdef _MSC_VER
#pragma once
#endif

/*!
 * \file qt_meta_object.h
 * \author XDL Team
 * \ingroup QxTraits
 * \brief qx::trait::qt_meta_object<T>::get() : if T is based on QObject class, then return QMetaObject instance of Qt introspection engine, else return NULL
 */

#include <QtCore/qmetaobject.h>
#include <QtCore/qmetatype.h>

namespace qx
{
   namespace trait
   {

      /*!
       * \ingroup QxTraits
       * \brief qx::trait::qt_meta_object<T>::get() : if T is based on QObject class, then return QMetaObject instance of Qt introspection engine, else return NULL
       */
      template <typename T>
      class qt_meta_object
      {

      public:
         enum
         {
            is_valid = (std::is_base_of<QObject, T>::value)
         };

         static const QMetaObject *get()
         {
            return qtMetaObject<qt_meta_object<T>::is_valid, 0>::get();
         }

      private:
         template <bool isQObject /* = false */, int dummy>
         struct qtMetaObject
         {
            static inline const QMetaObject *get() { return NULL; }
         };

         template <int dummy>
         struct qtMetaObject<true, dummy>
         {
            static inline const QMetaObject *get() { return (&T::staticMetaObject); }
         };
      };

   } // namespace trait
} // namespace qx

#endif // _QX_QT_META_OBJECT_H_
