plugin.common.h

/*
    Lightmetrica : A research-oriented renderer

    Copyright (c) 2014 Hisanari Otsu

    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 3 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, see <http://www.gnu.org/licenses/>.
*/

#pragma once
#ifndef LIB_LIGHTMETRICA_PLUGIN_COMMON_H
#define LIB_LIGHTMETRICA_PLUGIN_COMMON_H

#include "component.h"
#include <string>
#include <functional>

LM_NAMESPACE_BEGIN

class PluginManager
{
public:

    typedef std::function<Component* ()> CreateComponentFunc;

private:

    PluginManager() {}

private:

    LM_DISABLE_COPY_AND_MOVE(PluginManager);

public:

    static bool Register(const std::string& interfaceType, const std::string& implType, const CreateComponentFunc& func);

};

template <typename ImplType, typename InterfaceType>
class ComponentPluginFactoryEntry
{
public:

    static ComponentPluginFactoryEntry<ImplType, InterfaceType>& Instance()
    {
        static ComponentPluginFactoryEntry<ImplType, InterfaceType> instance;
        return instance;
    }

private:

    ComponentPluginFactoryEntry()
    {
        if (!PluginManager::Register(InterfaceType::InterfaceTypeName(), ImplType::ImplTypeName(), [](){ return new ImplType; }))
        {
            LM_LOG_ERROR("Failed to register plugin '" + std::string(ImplType::ImplTypeName()) + "'");
        }
    }

private:

    ComponentPluginFactoryEntry(const ComponentPluginFactoryEntry<ImplType, InterfaceType>&);
    ComponentPluginFactoryEntry(ComponentPluginFactoryEntry<ImplType, InterfaceType>&&);
    void operator=(const ComponentPluginFactoryEntry<ImplType, InterfaceType>&);
    void operator=(ComponentPluginFactoryEntry<ImplType, InterfaceType>&&);

};

LM_NAMESPACE_END

#define LM_COMPONENT_REGISTER_PLUGIN_IMPL(ImplType, InterfaceType)                                  \
    namespace {                                                                                     \
                                                                                                    \
        template <typename T1, typename T2>                                                         \
        class ComponentPluginFactoryEntryInstance;                                                  \
                                                                                                    \
        template <>                                                                                 \
        class ComponentPluginFactoryEntryInstance<ImplType, InterfaceType>                          \
        {                                                                                           \
            static const ::lightmetrica::ComponentPluginFactoryEntry<ImplType, InterfaceType>& reg; \
        };                                                                                          \
                                                                                                    \
        const ::lightmetrica::ComponentPluginFactoryEntry<ImplType, InterfaceType>&                 \
            ComponentPluginFactoryEntryInstance<ImplType, InterfaceType>::reg =                     \
                ::lightmetrica::ComponentPluginFactoryEntry<ImplType, InterfaceType>::Instance();   \
                                                                                                    \
        LM_COMPONENT_CHECK_IS_DERIVED_CLASS(ImplType, InterfaceType);                               \
        LM_COMPONENT_CHECK_IS_DERIVED_CLASS(InterfaceType, Component);                              \
        LM_COMPONENT_CHECK_HAS_MEMBER_FUNCTION(ImplType, ImplTypeName);                             \
        LM_COMPONENT_CHECK_HAS_MEMBER_FUNCTION(InterfaceType, InterfaceTypeName);                   \
                                                                                                    \
    }

#endif // LIB_LIGHTMETRICA_PLUGIN_COMMON_H