urid.hpp

/*
    urid.hpp - support file for writing LV2 plugins in C++
    Copyright (C) 2012 Michael Fisher <mfisher31@gmail.com>

    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, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 01222-1307  USA
*/

#ifndef LVTK_URID_HPP
#define LVTK_URID_HPP

#include <lv2/lv2plug.in/ns/ext/urid/urid.h>

namespace lvtk
{
    typedef uint32_t     (*MapFunc)(const char* symbol);

    typedef const char*  (*UnmapFunc)(uint32_t id);

    template<bool Required = true>
    struct URID
    {
        template<class Derived>
        struct I : Extension<Required>
        {
            I() : p_map(0), p_unmap(0)  { }

            static void
            map_feature_handlers (FeatureHandlerMap& hmap)
            {
                hmap[LV2_URID__map]   = &I<Derived>::handle_map_feature;
                hmap[LV2_URID__unmap] = &I<Derived>::handle_unmap_feature;
            }

            static void
            handle_map_feature (void* instance, void* data)
            {
                Derived* d = reinterpret_cast<Derived*>(instance);
                I<Derived>* mixin = static_cast<I<Derived>*>(d);

                mixin->p_map = reinterpret_cast<LV2_URID_Map*>(data);
                mixin->m_ok = true;
            }

            static void
            handle_unmap_feature (void* instance, void* data)
            {
                Derived* d = reinterpret_cast<Derived*> (instance);
                I<Derived>* mixin = static_cast<I<Derived>*>(d);

                mixin->p_unmap = reinterpret_cast<LV2_URID_Unmap*>(data);
                mixin->m_ok = true;
            }

            bool
            check_ok()
            {
                if (LVTK_DEBUG)
                {
                    std::clog << "    [URID] Validation "
                            << (this->m_ok ? "succeeded" : "failed")
                            << "." << std::endl;
                }
                return this->m_ok;
            }

            const char*
            unmap (LV2_URID urid)
            {
                if (p_unmap != NULL)
                    return p_unmap->unmap(p_unmap->handle, urid);
                return "";
            }

            LV2_URID
            map (const char* uri)
            {
                if (p_map != NULL)
                    return p_map->map(p_map->handle, uri);
                return 0;
            }

            LV2_URID_Map* get_urid_map() const { return p_map; }

            LV2_URID_Unmap* get_urid_unmap() const { return p_unmap; }

        protected:

            LV2_URID_Map   *p_map;
            LV2_URID_Unmap *p_unmap;

        };
    };
}

#endif /* LVTK_URID_HPP */