Carla/source/plugin/carla-lv2.cpp

/*
 * Carla Native Plugins
 * Copyright (C) 2013-2017 Filipe Coelho <falktx@falktx.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 2 of
 * the License, or 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.
 *
 * For a full copy of the GNU General Public License see the doc/GPL.txt file.
 */

#define CARLA_NATIVE_PLUGIN_LV2
#include "carla-base.cpp"

#include "CarlaLv2Utils.hpp"
#include "CarlaMathUtils.hpp"
#include "CarlaString.hpp"

// -----------------------------------------------------------------------
// LV2 descriptor functions

class NativePlugin : public Lv2PluginBaseClass
{
public:
    static const uint32_t kMaxMidiEvents = 512;

    NativePlugin(const NativePluginDescriptor* const desc,
                 const double sampleRate,
                 const char* const bundlePath,
                 const LV2_Feature* const* const features)
        : Lv2PluginBaseClass(sampleRate, features),
          fHandle(nullptr),
          fHost(),
          fDescriptor(desc),
#ifdef CARLA_PROPER_CPP11_SUPPORT
          fProgramDesc({0, 0, nullptr}),
#endif
          fMidiEventCount(0),
          fTimeInfo(),
          fLastPositionData(),
          fUI(),
          fPorts()
    {
        carla_zeroStruct(fHost);

        if (! loadedInProperHost())
            return;

        CarlaString resourceDir(bundlePath);
        resourceDir += CARLA_OS_SEP_STR "resources" CARLA_OS_SEP_STR;

        fHost.handle      = this;
        fHost.resourceDir = resourceDir.dupSafe();
        fHost.uiName      = nullptr;
        fHost.uiParentId  = 0;

        fHost.get_buffer_size        = host_get_buffer_size;
        fHost.get_sample_rate        = host_get_sample_rate;
        fHost.is_offline             = host_is_offline;
        fHost.get_time_info          = host_get_time_info;
        fHost.write_midi_event       = host_write_midi_event;
        fHost.ui_parameter_changed   = host_ui_parameter_changed;
        fHost.ui_custom_data_changed = host_ui_custom_data_changed;
        fHost.ui_closed              = host_ui_closed;
        fHost.ui_open_file           = host_ui_open_file;
        fHost.ui_save_file           = host_ui_save_file;
        fHost.dispatcher             = host_dispatcher;
    }

    ~NativePlugin()
    {
        CARLA_SAFE_ASSERT(fHandle == nullptr);

        if (fHost.resourceDir != nullptr)
        {
            delete[] fHost.resourceDir;
            fHost.resourceDir = nullptr;
        }
    }

    bool init()
    {
        if (fHost.resourceDir == nullptr)
            return false;

        if (fDescriptor->instantiate == nullptr || fDescriptor->process == nullptr)
        {
            carla_stderr("Plugin is missing something...");
            return false;
        }

        carla_zeroStructs(fMidiEvents, kMaxMidiEvents);
        carla_zeroStruct(fTimeInfo);

        fHandle = fDescriptor->instantiate(&fHost);
        CARLA_SAFE_ASSERT_RETURN(fHandle != nullptr, false);

        if (fDescriptor->midiIns > 0)
            fUI.portOffset += fDescriptor->midiIns;
        else if (fDescriptor->hints & NATIVE_PLUGIN_USES_TIME)
            fUI.portOffset += 1;

        fUI.portOffset += fDescriptor->midiOuts;
        fUI.portOffset += 1; // freewheel
        fUI.portOffset += fDescriptor->audioIns;
        fUI.portOffset += fDescriptor->audioOuts;

        fPorts.init(fDescriptor, fHandle);
        return true;
    }

    // -------------------------------------------------------------------
    // LV2 functions

    void lv2_connect_port(const uint32_t port, void* const dataLocation)
    {
        fPorts.connectPort(fDescriptor, port, dataLocation);
    }

    void lv2_activate()
    {
        if (fDescriptor->activate != nullptr)
            fDescriptor->activate(fHandle);

        carla_zeroStruct(fTimeInfo);

        // hosts may not send all values, resulting on some invalid data
        fTimeInfo.bbt.bar   = 1;
        fTimeInfo.bbt.beat  = 1;
        fTimeInfo.bbt.tick  = 0;
        fTimeInfo.bbt.barStartTick = 0;
        fTimeInfo.bbt.beatsPerBar  = 4;
        fTimeInfo.bbt.beatType     = 4;
        fTimeInfo.bbt.ticksPerBeat = 960.0;
        fTimeInfo.bbt.beatsPerMinute = 120.0;
    }

    void lv2_deactivate()
    {
        if (fDescriptor->deactivate != nullptr)
            fDescriptor->deactivate(fHandle);
    }

    void lv2_cleanup()
    {
        if (fDescriptor->cleanup != nullptr)
            fDescriptor->cleanup(fHandle);

        fHandle = nullptr;
    }

    void lv2_run(const uint32_t frames)
    {
        fIsOffline = (fPorts.freewheel != nullptr && *fPorts.freewheel >= 0.5f);

        // cache midi events and time information first
        if (fDescriptor->midiIns > 0 || (fDescriptor->hints & NATIVE_PLUGIN_USES_TIME) != 0)
        {
            fMidiEventCount = 0;
            carla_zeroStructs(fMidiEvents, kMaxMidiEvents);

            if (fDescriptor->hints & NATIVE_PLUGIN_USES_TIME)
            {
                LV2_ATOM_SEQUENCE_FOREACH(fPorts.eventsIn[0], event)
                {
                    if (event == nullptr)
                        continue;
                    if (event->body.type != fURIs.atomBlank && event->body.type != fURIs.atomObject)
                        continue;

                    const LV2_Atom_Object* const obj((const LV2_Atom_Object*)&event->body);

                    if (obj->body.otype != fURIs.timePos)
                        continue;

                    LV2_Atom* bar     = nullptr;
                    LV2_Atom* barBeat = nullptr;
                    LV2_Atom* beatUnit = nullptr;
                    LV2_Atom* beatsPerBar = nullptr;
                    LV2_Atom* beatsPerMinute = nullptr;
                    LV2_Atom* frame = nullptr;
                    LV2_Atom* speed = nullptr;
                    LV2_Atom* ticksPerBeat = nullptr;

                    lv2_atom_object_get(obj,
                                        fURIs.timeBar, &bar,
                                        fURIs.timeBarBeat, &barBeat,
                                        fURIs.timeBeatUnit, &beatUnit,
                                        fURIs.timeBeatsPerBar, &beatsPerBar,
                                        fURIs.timeBeatsPerMinute, &beatsPerMinute,
                                        fURIs.timeFrame, &frame,
                                        fURIs.timeSpeed, &speed,
                                        fURIs.timeTicksPerBeat, &ticksPerBeat,
                                        0);

                    // need to handle this first as other values depend on it
                    if (ticksPerBeat != nullptr)
                    {
                        double ticksPerBeatValue = -1.0;

                        /**/ if (ticksPerBeat->type == fURIs.atomDouble)
                            ticksPerBeatValue = ((LV2_Atom_Double*)ticksPerBeat)->body;
                        else if (ticksPerBeat->type == fURIs.atomFloat)
                            ticksPerBeatValue = ((LV2_Atom_Float*)ticksPerBeat)->body;
                        else if (ticksPerBeat->type == fURIs.atomInt)
                            ticksPerBeatValue = static_cast<double>(((LV2_Atom_Int*)ticksPerBeat)->body);
                        else if (ticksPerBeat->type == fURIs.atomLong)
                            ticksPerBeatValue = static_cast<double>(((LV2_Atom_Long*)ticksPerBeat)->body);
                        else
                            carla_stderr("Unknown lv2 ticksPerBeat value type");

                        if (ticksPerBeatValue > 0.0)
                            fTimeInfo.bbt.ticksPerBeat = fLastPositionData.ticksPerBeat = ticksPerBeatValue;
                        else
                            carla_stderr("Invalid lv2 ticksPerBeat value");
                    }

                    // same
                    if (speed != nullptr)
                    {
                        /**/ if (speed->type == fURIs.atomDouble)
                            fLastPositionData.speed = ((LV2_Atom_Double*)speed)->body;
                        else if (speed->type == fURIs.atomFloat)
                            fLastPositionData.speed = ((LV2_Atom_Float*)speed)->body;
                        else if (speed->type == fURIs.atomInt)
                            fLastPositionData.speed = static_cast<double>(((LV2_Atom_Int*)speed)->body);
                        else if (speed->type == fURIs.atomLong)
                            fLastPositionData.speed = static_cast<double>(((LV2_Atom_Long*)speed)->body);
                        else
                            carla_stderr("Unknown lv2 speed value type");

                        fTimeInfo.playing = carla_isNotZero(fLastPositionData.speed);

                        if (fTimeInfo.playing && fLastPositionData.beatsPerMinute > 0.0f)
                        {
                            fTimeInfo.bbt.beatsPerMinute = fLastPositionData.beatsPerMinute*
                                                           std::abs(fLastPositionData.speed);
                        }
                    }

                    if (bar != nullptr)
                    {
                        int64_t barValue = -1;

                        /**/ if (bar->type == fURIs.atomDouble)
                            barValue = static_cast<int64_t>(((LV2_Atom_Double*)bar)->body);
                        else if (bar->type == fURIs.atomFloat)
                            barValue = static_cast<int64_t>(((LV2_Atom_Float*)bar)->body);
                        else if (bar->type == fURIs.atomInt)
                            barValue = ((LV2_Atom_Int*)bar)->body;
                        else if (bar->type == fURIs.atomLong)
                            barValue = ((LV2_Atom_Long*)bar)->body;
                        else
                            carla_stderr("Unknown lv2 bar value type");

                        if (barValue >= 0 && barValue < INT32_MAX)
                        {
                            fLastPositionData.bar   = static_cast<int32_t>(barValue);
                            fLastPositionData.bar_f = static_cast<float>(barValue);
                            fTimeInfo.bbt.bar = fLastPositionData.bar + 1;
                        }
                        else
                        {
                            carla_stderr("Invalid lv2 bar value");
                        }
                    }

                    if (barBeat != nullptr)
                    {
                        double barBeatValue = -1.0;

                        /**/ if (barBeat->type == fURIs.atomDouble)
                            barBeatValue = ((LV2_Atom_Double*)barBeat)->body;
                        else if (barBeat->type == fURIs.atomFloat)
                            barBeatValue = ((LV2_Atom_Float*)barBeat)->body;
                        else if (barBeat->type == fURIs.atomInt)
                            barBeatValue = static_cast<float>(((LV2_Atom_Int*)barBeat)->body);
                        else if (barBeat->type == fURIs.atomLong)
                            barBeatValue = static_cast<float>(((LV2_Atom_Long*)barBeat)->body);
                        else
                            carla_stderr("Unknown lv2 barBeat value type");

                        if (barBeatValue >= 0.0)
                        {
                            fLastPositionData.barBeat = static_cast<float>(barBeatValue);

                            const double rest  = std::fmod(barBeatValue, 1.0);
                            fTimeInfo.bbt.beat = static_cast<int32_t>(barBeatValue-rest+1.0);
                            fTimeInfo.bbt.tick = static_cast<int32_t>(rest*fTimeInfo.bbt.ticksPerBeat+0.5);
                        }
                        else
                        {
                            carla_stderr("Invalid lv2 barBeat value");
                        }
                    }

                    if (beatUnit != nullptr)
                    {
                        int64_t beatUnitValue = -1;

                        /**/ if (beatUnit->type == fURIs.atomDouble)
                            beatUnitValue = static_cast<int64_t>(((LV2_Atom_Double*)beatUnit)->body);
                        else if (beatUnit->type == fURIs.atomFloat)
                            beatUnitValue = static_cast<int64_t>(((LV2_Atom_Float*)beatUnit)->body);
                        else if (beatUnit->type == fURIs.atomInt)
                            beatUnitValue = ((LV2_Atom_Int*)beatUnit)->body;
                        else if (beatUnit->type == fURIs.atomLong)
                            beatUnitValue = ((LV2_Atom_Long*)beatUnit)->body;
                        else
                            carla_stderr("Unknown lv2 beatUnit value type");

                        if (beatUnitValue > 0 && beatUnitValue < UINT32_MAX)
                        {
                            fLastPositionData.beatUnit = static_cast<uint32_t>(beatUnitValue);
                            fTimeInfo.bbt.beatType     = static_cast<float>(beatUnitValue);
                        }
                        else
                        {
                            carla_stderr("Invalid lv2 beatUnit value");
                        }
                    }

                    if (beatsPerBar != nullptr)
                    {
                        float beatsPerBarValue = -1.0f;

                        /**/ if (beatsPerBar->type == fURIs.atomDouble)
                            beatsPerBarValue = static_cast<float>(((LV2_Atom_Double*)beatsPerBar)->body);
                        else if (beatsPerBar->type == fURIs.atomFloat)
                            beatsPerBarValue = ((LV2_Atom_Float*)beatsPerBar)->body;
                        else if (beatsPerBar->type == fURIs.atomInt)
                            beatsPerBarValue = static_cast<float>(((LV2_Atom_Int*)beatsPerBar)->body);
                        else if (beatsPerBar->type == fURIs.atomLong)
                            beatsPerBarValue = static_cast<float>(((LV2_Atom_Long*)beatsPerBar)->body);
                        else
                            carla_stderr("Unknown lv2 beatsPerBar value type");

                        if (beatsPerBarValue > 0.0f)
                            fTimeInfo.bbt.beatsPerBar = fLastPositionData.beatsPerBar = beatsPerBarValue;
                        else
                            carla_stderr("Invalid lv2 beatsPerBar value");
                    }

                    if (beatsPerMinute != nullptr)
                    {
                        double beatsPerMinuteValue = -1.0;

                        /**/ if (beatsPerMinute->type == fURIs.atomDouble)
                            beatsPerMinuteValue = ((LV2_Atom_Double*)beatsPerMinute)->body;
                        else if (beatsPerMinute->type == fURIs.atomFloat)
                            beatsPerMinuteValue = ((LV2_Atom_Float*)beatsPerMinute)->body;
                        else if (beatsPerMinute->type == fURIs.atomInt)
                            beatsPerMinuteValue = static_cast<double>(((LV2_Atom_Int*)beatsPerMinute)->body);
                        else if (beatsPerMinute->type == fURIs.atomLong)
                            beatsPerMinuteValue = static_cast<double>(((LV2_Atom_Long*)beatsPerMinute)->body);
                        else
                            carla_stderr("Unknown lv2 beatsPerMinute value type");

                        if (beatsPerMinuteValue >= 12.0 && beatsPerMinuteValue <= 999.0)
                        {
                            fTimeInfo.bbt.beatsPerMinute = fLastPositionData.beatsPerMinute = beatsPerMinuteValue;

                            if (carla_isNotZero(fLastPositionData.speed))
                                fTimeInfo.bbt.beatsPerMinute *= std::abs(fLastPositionData.speed);
                        }
                        else
                        {
                            carla_stderr("Invalid lv2 beatsPerMinute value");
                        }
                    }

                    if (frame != nullptr)
                    {
                        int64_t frameValue = -1;

                        /**/ if (frame->type == fURIs.atomDouble)
                            frameValue = static_cast<int64_t>(((LV2_Atom_Double*)frame)->body);
                        else if (frame->type == fURIs.atomFloat)
                            frameValue = static_cast<int64_t>(((LV2_Atom_Float*)frame)->body);
                        else if (frame->type == fURIs.atomInt)
                            frameValue = ((LV2_Atom_Int*)frame)->body;
                        else if (frame->type == fURIs.atomLong)
                            frameValue = ((LV2_Atom_Long*)frame)->body;
                        else
                            carla_stderr("Unknown lv2 frame value type");

                        if (frameValue >= 0)
                            fTimeInfo.frame = fLastPositionData.frame = static_cast<uint64_t>(frameValue);
                        else
                            carla_stderr("Invalid lv2 frame value");
                    }

                    fTimeInfo.bbt.barStartTick = fTimeInfo.bbt.ticksPerBeat*
                                                 fTimeInfo.bbt.beatsPerBar*
                                                 (fTimeInfo.bbt.bar-1);

                    fTimeInfo.bbt.valid = (fLastPositionData.beatsPerMinute > 0.0 &&
                                           fLastPositionData.beatUnit > 0 &&
                                           fLastPositionData.beatsPerBar > 0.0f);
                }
            }

            for (uint32_t i=0; i < fDescriptor->midiIns; ++i)
            {
                LV2_ATOM_SEQUENCE_FOREACH(fPorts.eventsIn[i], event)
                {
                    if (event == nullptr)
                        continue;
                    if (event->body.type != fURIs.midiEvent)
                        continue;
                    if (event->body.size > 4)
                        continue;
                    if (event->time.frames >= frames)
                        break;
                    if (fMidiEventCount >= kMaxMidiEvents)
                        break;

                    const uint8_t* const data((const uint8_t*)(event + 1));

                    NativeMidiEvent& nativeEvent(fMidiEvents[fMidiEventCount++]);

                    nativeEvent.port = (uint8_t)i;
                    nativeEvent.size = (uint8_t)event->body.size;
                    nativeEvent.time = (uint32_t)event->time.frames;

                    uint32_t j=0;
                    for (uint32_t size=event->body.size; j<size; ++j)
                        nativeEvent.data[j] = data[j];
                    for (; j<4; ++j)
                        nativeEvent.data[j] = 0;
                }
            }
        }

        // init midi out data
        if (fDescriptor->midiOuts > 0)
        {
            for (uint32_t i=0, size=fDescriptor->midiOuts; i<size; ++i)
            {
                LV2_Atom_Sequence* const seq(fPorts.midiOuts[i]);
                CARLA_SAFE_ASSERT_CONTINUE(seq != nullptr);

                Ports::MidiOutData& mData(fPorts.midiOutData[i]);
                mData.capacity = seq->atom.size;
                mData.offset   = 0;

                seq->atom.size = sizeof(LV2_Atom_Sequence_Body);
                seq->atom.type = fURIs.atomSequence;
                seq->body.unit = 0;
                seq->body.pad  = 0;
            }
        }

        // Check for updated parameters
        float curValue;

        for (uint32_t i=0; i < fPorts.paramCount; ++i)
        {
            if (fPorts.paramsOut[i])
                continue;

            CARLA_SAFE_ASSERT_CONTINUE(fPorts.paramsPtr[i] != nullptr)

            curValue = *fPorts.paramsPtr[i];

            if (carla_isEqual(fPorts.paramsLast[i], curValue))
                continue;

            fPorts.paramsLast[i] = curValue;
            fDescriptor->set_parameter_value(fHandle, i, curValue);
        }

        if (frames == 0)
            return updateParameterOutputs();

        // FIXME
        fDescriptor->process(fHandle,
                             const_cast<float**>(fPorts.audioIns), fPorts.audioOuts, frames,
                             fMidiEvents, fMidiEventCount);

        // update timePos for next callback
        if (carla_isNotZero(fLastPositionData.speed))
        {
            if (fLastPositionData.speed > 0.0)
            {
                // playing forwards
                fLastPositionData.frame += frames;
            }
            else
            {
                // playing backwards
                if (frames >= fLastPositionData.frame)
                    fLastPositionData.frame = 0;
                else
                    fLastPositionData.frame -= frames;
            }

            fTimeInfo.frame = fLastPositionData.frame;

            if (fTimeInfo.bbt.valid)
            {
                const double beatsPerMinute = fLastPositionData.beatsPerMinute * fLastPositionData.speed;
                const double framesPerBeat  = 60.0 * fSampleRate / beatsPerMinute;
                const double addedBarBeats  = double(frames) / framesPerBeat;

                if (fLastPositionData.barBeat >= 0.0f)
                {
                    fLastPositionData.barBeat = std::fmod(fLastPositionData.barBeat+static_cast<float>(addedBarBeats),
                                                          fLastPositionData.beatsPerBar);

                    const double rest  = std::fmod(fLastPositionData.barBeat, 1.0f);
                    fTimeInfo.bbt.beat = static_cast<int32_t>(fLastPositionData.barBeat-rest+1.0);
                    fTimeInfo.bbt.tick = static_cast<int32_t>(rest*fTimeInfo.bbt.ticksPerBeat+0.5);

                    if (fLastPositionData.bar_f >= 0.0f)
                    {
                        fLastPositionData.bar_f += std::floor((fLastPositionData.barBeat+static_cast<float>(addedBarBeats))/
                                                               fLastPositionData.beatsPerBar);

                        if (fLastPositionData.bar_f <= 0.0f)
                        {
                            fLastPositionData.bar   = 0;
                            fLastPositionData.bar_f = 0.0f;
                        }
                        else
                        {
                            fLastPositionData.bar = static_cast<int32_t>(fLastPositionData.bar_f+0.5f);
                        }

                        fTimeInfo.bbt.bar = fLastPositionData.bar + 1;

                        fTimeInfo.bbt.barStartTick = fTimeInfo.bbt.ticksPerBeat*
                                                     fTimeInfo.bbt.beatsPerBar*
                                                     (fTimeInfo.bbt.bar-1);
                    }
                }
            }
        }

        updateParameterOutputs();
    }

    // -------------------------------------------------------------------

    uint32_t lv2_get_options(LV2_Options_Option* const /*options*/) const
    {
        // currently unused
        return LV2_OPTIONS_SUCCESS;
    }

    uint32_t lv2_set_options(const LV2_Options_Option* const options)
    {
        for (int i=0; options[i].key != 0; ++i)
        {
            if (options[i].key == fUridMap->map(fUridMap->handle, LV2_BUF_SIZE__nominalBlockLength))
            {
                if (options[i].type == fURIs.atomInt)
                {
                    const int value(*(const int*)options[i].value);
                    CARLA_SAFE_ASSERT_CONTINUE(value > 0);

                    fBufferSize = static_cast<uint32_t>(value);

                    if (fDescriptor->dispatcher != nullptr)
                        fDescriptor->dispatcher(fHandle, NATIVE_PLUGIN_OPCODE_BUFFER_SIZE_CHANGED, 0, value, nullptr, 0.0f);
                }
                else
                    carla_stderr("Host changed nominalBlockLength but with wrong value type");
            }
            else if (options[i].key == fUridMap->map(fUridMap->handle, LV2_BUF_SIZE__maxBlockLength) && ! fUsingNominal)
            {
                if (options[i].type == fURIs.atomInt)
                {
                    const int value(*(const int*)options[i].value);
                    CARLA_SAFE_ASSERT_CONTINUE(value > 0);

                    fBufferSize = static_cast<uint32_t>(value);

                    if (fDescriptor->dispatcher != nullptr)
                        fDescriptor->dispatcher(fHandle, NATIVE_PLUGIN_OPCODE_BUFFER_SIZE_CHANGED, 0, value, nullptr, 0.0f);
                }
                else
                    carla_stderr("Host changed maxBlockLength but with wrong value type");
            }
            else if (options[i].key == fUridMap->map(fUridMap->handle, LV2_CORE__sampleRate))
            {
                if (options[i].type == fURIs.atomDouble)
                {
                    const double value(*(const double*)options[i].value);
                    CARLA_SAFE_ASSERT_CONTINUE(value > 0.0);

                    fSampleRate = value;

                    if (fDescriptor->dispatcher != nullptr)
                        fDescriptor->dispatcher(fHandle, NATIVE_PLUGIN_OPCODE_SAMPLE_RATE_CHANGED, 0, 0, nullptr, (float)fSampleRate);
                }
                else
                    carla_stderr("Host changed sampleRate but with wrong value type");
            }
        }

        return LV2_OPTIONS_SUCCESS;
    }

    const LV2_Program_Descriptor* lv2_get_program(const uint32_t index)
    {
        if (fDescriptor->category == NATIVE_PLUGIN_CATEGORY_SYNTH)
            return nullptr;
        if (fDescriptor->get_midi_program_count == nullptr)
            return nullptr;
        if (fDescriptor->get_midi_program_info == nullptr)
            return nullptr;
        if (index >= fDescriptor->get_midi_program_count(fHandle))
            return nullptr;

        const NativeMidiProgram* const midiProg(fDescriptor->get_midi_program_info(fHandle, index));

        if (midiProg == nullptr)
            return nullptr;

        fProgramDesc.bank    = midiProg->bank;
        fProgramDesc.program = midiProg->program;
        fProgramDesc.name    = midiProg->name;

        return &fProgramDesc;
    }

    void lv2_select_program(uint32_t bank, uint32_t program)
    {
        if (fDescriptor->category == NATIVE_PLUGIN_CATEGORY_SYNTH)
            return;
        if (fDescriptor->set_midi_program == nullptr)
            return;

        fDescriptor->set_midi_program(fHandle, 0, bank, program);

        for (uint32_t i=0; i < fPorts.paramCount; ++i)
        {
            fPorts.paramsLast[i] = fDescriptor->get_parameter_value(fHandle, i);

            if (fPorts.paramsPtr[i] != nullptr)
                *fPorts.paramsPtr[i] = fPorts.paramsLast[i];
        }
    }

    LV2_State_Status lv2_save(const LV2_State_Store_Function store, const LV2_State_Handle handle, const uint32_t /*flags*/, const LV2_Feature* const* const /*features*/) const
    {
        if ((fDescriptor->hints & NATIVE_PLUGIN_USES_STATE) == 0 || fDescriptor->get_state == nullptr)
            return LV2_STATE_ERR_NO_FEATURE;

        if (char* const state = fDescriptor->get_state(fHandle))
        {
            store(handle, fUridMap->map(fUridMap->handle, "http://kxstudio.sf.net/ns/carla/chunk"), state, std::strlen(state)+1, fURIs.atomString, LV2_STATE_IS_POD|LV2_STATE_IS_PORTABLE);
            std::free(state);
            return LV2_STATE_SUCCESS;
        }

        return LV2_STATE_ERR_UNKNOWN;
    }

    LV2_State_Status lv2_restore(const LV2_State_Retrieve_Function retrieve, const LV2_State_Handle handle, uint32_t flags, const LV2_Feature* const* const /*features*/) const
    {
        if ((fDescriptor->hints & NATIVE_PLUGIN_USES_STATE) == 0 || fDescriptor->set_state == nullptr)
            return LV2_STATE_ERR_NO_FEATURE;

        size_t   size = 0;
        uint32_t type = 0;
        const void* const data = retrieve(handle, fUridMap->map(fUridMap->handle, "http://kxstudio.sf.net/ns/carla/chunk"), &size, &type, &flags);

        if (size == 0)
            return LV2_STATE_ERR_UNKNOWN;
        if (type == 0)
            return LV2_STATE_ERR_UNKNOWN;
        if (data == nullptr)
            return LV2_STATE_ERR_UNKNOWN;
        if (type != fURIs.atomString)
            return LV2_STATE_ERR_BAD_TYPE;

        fDescriptor->set_state(fHandle, (const char*)data);

        return LV2_STATE_SUCCESS;
    }

    // -------------------------------------------------------------------

    void lv2ui_instantiate(LV2UI_Write_Function writeFunction, LV2UI_Controller controller,
                           LV2UI_Widget* widget, const LV2_Feature* const* features, const bool isEmbed)
    {
        fUI.writeFunction = writeFunction;
        fUI.controller = controller;
        fUI.isEmbed = isEmbed;

#ifdef CARLA_OS_LINUX
        // ---------------------------------------------------------------
        // show embed UI if needed

        if (isEmbed)
        {
            intptr_t parentId = 0;
            const LV2UI_Resize* uiResize = nullptr;

            for (int i=0; features[i] != nullptr; ++i)
            {
                if (std::strcmp(features[i]->URI, LV2_UI__parent) == 0)
                {
                    parentId = (intptr_t)features[i]->data;
                }
                else if (std::strcmp(features[i]->URI, LV2_UI__resize) == 0)
                {
                    uiResize = (const LV2UI_Resize*)features[i]->data;
                }
            }

            // -----------------------------------------------------------
            // see if the host can really embed the UI

            if (parentId != 0)
            {
                // wait for remote side to be ready
                fDescriptor->dispatcher(fHandle, NATIVE_PLUGIN_OPCODE_NULL, (int32_t)0xDEADF00D, 0xC0C0B00B, nullptr, 0.0f);

                if (uiResize && uiResize->ui_resize != nullptr)
                    uiResize->ui_resize(uiResize->handle, 740, 512);

                fHost.uiName = carla_strdup(fDescriptor->name);
                fUI.isVisible = true;

                char strBuf[0xff+1];
                strBuf[0xff] = '\0';
                std::snprintf(strBuf, 0xff, P_INTPTR, parentId);

                carla_setenv("CARLA_PLUGIN_EMBED_WINID", strBuf);

                fDescriptor->ui_show(fHandle, true);

                carla_setenv("CARLA_PLUGIN_EMBED_WINID", "0");

                const intptr_t winId(fDescriptor->dispatcher(fHandle, NATIVE_PLUGIN_OPCODE_NULL, (int32_t)0xDEADF00D, 0xC0C0B00B, nullptr, 0.0f));
                CARLA_SAFE_ASSERT_RETURN(winId != 0,);

                *widget = (LV2UI_Widget)winId;
                return;
            }
        }
#endif

        // ---------------------------------------------------------------
        // see if the host supports external-ui

        for (int i=0; features[i] != nullptr; ++i)
        {
            if (std::strcmp(features[i]->URI, LV2_EXTERNAL_UI__Host) == 0 ||
                std::strcmp(features[i]->URI, LV2_EXTERNAL_UI_DEPRECATED_URI) == 0)
            {
                fUI.host = (const LV2_External_UI_Host*)features[i]->data;
                break;
            }
        }

        if (fUI.host != nullptr)
        {
            fHost.uiName = carla_strdup(fUI.host->plugin_human_id);
            *widget = (LV2_External_UI_Widget_Compat*)this;
            return;
        }

        // ---------------------------------------------------------------
        // no external-ui support, use showInterface

        for (int i=0; features[i] != nullptr; ++i)
        {
            if (std::strcmp(features[i]->URI, LV2_OPTIONS__options) == 0)
            {
                const LV2_Options_Option* const options((const LV2_Options_Option*)features[i]->data);

                for (int j=0; options[j].key != 0; ++j)
                {
                    if (options[j].key == fUridMap->map(fUridMap->handle, LV2_UI__windowTitle))
                    {
                        fHost.uiName = carla_strdup((const char*)options[j].value);
                        break;
                    }
                }
                break;
            }
        }

        if (fHost.uiName == nullptr)
            fHost.uiName = carla_strdup(fDescriptor->name);

        *widget = nullptr;
    }

    void lv2ui_port_event(uint32_t portIndex, uint32_t bufferSize, uint32_t format, const void* buffer) const
    {
        if (format != 0 || bufferSize != sizeof(float) || buffer == nullptr)
            return;
        if (portIndex >= fUI.portOffset || ! fUI.isVisible)
            return;
        if (fDescriptor->ui_set_parameter_value == nullptr)
            return;

        const float value(*(const float*)buffer);
        fDescriptor->ui_set_parameter_value(fHandle, portIndex-fUI.portOffset, value);
    }

    void lv2ui_cleanup()
    {
        if (fUI.isVisible)
            handleUiHide();

        fUI.host = nullptr;
        fUI.writeFunction = nullptr;
        fUI.controller = nullptr;

        if (fHost.uiName != nullptr)
        {
            delete[] fHost.uiName;
            fHost.uiName = nullptr;
        }
    }

    // -------------------------------------------------------------------

    void lv2ui_select_program(uint32_t bank, uint32_t program) const
    {
        if (fDescriptor->category == NATIVE_PLUGIN_CATEGORY_SYNTH)
            return;
        if (fDescriptor->ui_set_midi_program == nullptr)
            return;

        fDescriptor->ui_set_midi_program(fHandle, 0, bank, program);
    }

    // -------------------------------------------------------------------

    int lv2ui_idle() const
    {
        if (! fUI.isVisible)
            return 1;

        handleUiRun();
        return 0;
    }

    int lv2ui_show()
    {
        handleUiShow();
        return 0;
    }

    int lv2ui_hide()
    {
        handleUiHide();
        return 0;
    }

    // -------------------------------------------------------------------

protected:
    void handleUiRun() const override
    {
        if (fDescriptor->ui_idle != nullptr)
            fDescriptor->ui_idle(fHandle);
    }

    void handleUiShow() override
    {
        if (fDescriptor->ui_show != nullptr)
            fDescriptor->ui_show(fHandle, true);

        fUI.isVisible = true;
    }

    void handleUiHide() override
    {
        if (fDescriptor->ui_show != nullptr)
            fDescriptor->ui_show(fHandle, false);

        fUI.isVisible = false;
    }

    // -------------------------------------------------------------------

    bool handleWriteMidiEvent(const NativeMidiEvent* const event)
    {
        CARLA_SAFE_ASSERT_RETURN(fDescriptor->midiOuts > 0, false);
        CARLA_SAFE_ASSERT_RETURN(event != nullptr, false);
        CARLA_SAFE_ASSERT_RETURN(event->size > 0, false);

        const uint8_t port(event->port);
        CARLA_SAFE_ASSERT_RETURN(port < fDescriptor->midiOuts, false);

        LV2_Atom_Sequence* const seq(fPorts.midiOuts[port]);
        CARLA_SAFE_ASSERT_RETURN(seq != nullptr, false);

        Ports::MidiOutData& mData(fPorts.midiOutData[port]);

        if (sizeof(LV2_Atom_Event) + event->size > mData.capacity - mData.offset)
            return false;

        LV2_Atom_Event* const aev = (LV2_Atom_Event*)(LV2_ATOM_CONTENTS(LV2_Atom_Sequence, seq) + mData.offset);

        aev->time.frames = event->time;
        aev->body.size   = event->size;
        aev->body.type   = fURIs.midiEvent;
        std::memcpy(LV2_ATOM_BODY(&aev->body), event->data, event->size);

        const uint32_t size = lv2_atom_pad_size(static_cast<uint32_t>(sizeof(LV2_Atom_Event) + event->size));
        mData.offset       += size;
        seq->atom.size     += size;

        return true;
    }

    void handleUiParameterChanged(const uint32_t index, const float value) const
    {
        if (fUI.writeFunction != nullptr && fUI.controller != nullptr)
            fUI.writeFunction(fUI.controller, index+fUI.portOffset, sizeof(float), 0, &value);
    }

    void handleUiCustomDataChanged(const char* const /*key*/, const char* const /*value*/) const
    {
        //storeCustomData(key, value);
    }

    void handleUiClosed()
    {
        if (fUI.host != nullptr && fUI.host->ui_closed != nullptr && fUI.controller != nullptr)
            fUI.host->ui_closed(fUI.controller);

        fUI.host = nullptr;
        fUI.writeFunction = nullptr;
        fUI.controller = nullptr;
        fUI.isVisible = false;
    }

    const char* handleUiOpenFile(const bool /*isDir*/, const char* const /*title*/, const char* const /*filter*/) const
    {
        // TODO
        return nullptr;
    }

    const char* handleUiSaveFile(const bool /*isDir*/, const char* const /*title*/, const char* const /*filter*/) const
    {
        // TODO
        return nullptr;
    }

    intptr_t handleDispatcher(const NativeHostDispatcherOpcode opcode, const int32_t index, const intptr_t value, void* const ptr, const float opt)
    {
        carla_debug("NativePlugin::handleDispatcher(%i, %i, " P_INTPTR ", %p, %f)", opcode, index, value, ptr, opt);

        intptr_t ret = 0;

        switch (opcode)
        {
        case NATIVE_HOST_OPCODE_NULL:
        case NATIVE_HOST_OPCODE_UPDATE_PARAMETER:
        case NATIVE_HOST_OPCODE_UPDATE_MIDI_PROGRAM:
        case NATIVE_HOST_OPCODE_RELOAD_PARAMETERS:
        case NATIVE_HOST_OPCODE_RELOAD_MIDI_PROGRAMS:
        case NATIVE_HOST_OPCODE_RELOAD_ALL:
        case NATIVE_HOST_OPCODE_HOST_IDLE:
        case NATIVE_HOST_OPCODE_INTERNAL_PLUGIN:
            // nothing
            break;
        case NATIVE_HOST_OPCODE_UI_UNAVAILABLE:
            handleUiClosed();
            break;
        }

        return ret;

        // unused for now
        (void)index;
        (void)value;
        (void)ptr;
        (void)opt;
    }

    void updateParameterOutputs()
    {
        for (uint32_t i=0; i < fPorts.paramCount; ++i)
        {
            if (! fPorts.paramsOut[i])
                continue;

            fPorts.paramsLast[i] = fDescriptor->get_parameter_value(fHandle, i);

            if (fPorts.paramsPtr[i] != nullptr)
                *fPorts.paramsPtr[i] = fPorts.paramsLast[i];
        }
    }

    // -------------------------------------------------------------------

private:
    // Native data
    NativePluginHandle   fHandle;
    NativeHostDescriptor fHost;
    const NativePluginDescriptor* const fDescriptor;
    LV2_Program_Descriptor              fProgramDesc;

    uint32_t        fMidiEventCount;
    NativeMidiEvent fMidiEvents[kMaxMidiEvents];
    NativeTimeInfo  fTimeInfo;

    struct Lv2PositionData {
        int32_t  bar;
        float    bar_f;
        float    barBeat;
        uint32_t beatUnit;
        float    beatsPerBar;
        double   beatsPerMinute;
        uint64_t frame;
        double   speed;
        double   ticksPerBeat;

        Lv2PositionData()
            : bar(-1),
              bar_f(-1.0f),
              barBeat(-1.0f),
              beatUnit(0),
              beatsPerBar(0.0f),
              beatsPerMinute(-1.0),
              frame(0),
              speed(0.0),
              ticksPerBeat(-1.0) {}

    } fLastPositionData;

    struct UI {
        const LV2_External_UI_Host* host;
        LV2UI_Write_Function writeFunction;
        LV2UI_Controller controller;
        uint32_t portOffset;
        bool isEmbed;
        bool isVisible;

        UI()
            : host(nullptr),
              writeFunction(nullptr),
              controller(nullptr),
              portOffset(0),
              isEmbed(false),
              isVisible(false) {}
    } fUI;

    struct Ports {
        // need to save current state
        struct MidiOutData {
            uint32_t capacity;
            uint32_t offset;

            MidiOutData()
                : capacity(0),
                  offset(0) {}
        };

        const LV2_Atom_Sequence** eventsIn;
        /* */ LV2_Atom_Sequence** midiOuts;
        /* */ MidiOutData*        midiOutData;
        const float** audioIns;
        /* */ float** audioOuts;
        float*   freewheel;
        uint32_t paramCount;
        float*   paramsLast;
        float**  paramsPtr;
        bool*    paramsOut;

        Ports()
            : eventsIn(nullptr),
              midiOuts(nullptr),
              midiOutData(nullptr),
              audioIns(nullptr),
              audioOuts(nullptr),
              freewheel(nullptr),
              paramCount(0),
              paramsLast(nullptr),
              paramsPtr(nullptr),
              paramsOut(nullptr) {}

        ~Ports()
        {
            if (eventsIn != nullptr)
            {
                delete[] eventsIn;
                eventsIn = nullptr;
            }

            if (midiOuts != nullptr)
            {
                delete[] midiOuts;
                midiOuts = nullptr;
            }

            if (midiOutData != nullptr)
            {
                delete[] midiOutData;
                midiOutData = nullptr;
            }

            if (audioIns != nullptr)
            {
                delete[] audioIns;
                audioIns = nullptr;
            }

            if (audioOuts != nullptr)
            {
                delete[] audioOuts;
                audioOuts = nullptr;
            }

            if (paramsLast != nullptr)
            {
                delete[] paramsLast;
                paramsLast = nullptr;
            }

            if (paramsPtr != nullptr)
            {
                delete[] paramsPtr;
                paramsPtr = nullptr;
            }

            if (paramsOut != nullptr)
            {
                delete[] paramsOut;
                paramsOut = nullptr;
            }
        }

        void init(const NativePluginDescriptor* const desc, NativePluginHandle handle)
        {
            CARLA_SAFE_ASSERT_RETURN(desc != nullptr && handle != nullptr,)

            if (desc->midiIns > 0)
            {
                eventsIn = new const LV2_Atom_Sequence*[desc->midiIns];

                for (uint32_t i=0; i < desc->midiIns; ++i)
                    eventsIn[i] = nullptr;
            }
            else if (desc->hints & NATIVE_PLUGIN_USES_TIME)
            {
                eventsIn = new const LV2_Atom_Sequence*[1];
                eventsIn[0] = nullptr;
            }

            if (desc->midiOuts > 0)
            {
                midiOuts = new LV2_Atom_Sequence*[desc->midiOuts];
                midiOutData = new MidiOutData[desc->midiOuts];

                for (uint32_t i=0; i < desc->midiOuts; ++i)
                    midiOuts[i] = nullptr;
            }

            if (desc->audioIns > 0)
            {
                audioIns = new const float*[desc->audioIns];

                for (uint32_t i=0; i < desc->audioIns; ++i)
                    audioIns[i] = nullptr;
            }

            if (desc->audioOuts > 0)
            {
                audioOuts = new float*[desc->audioOuts];

                for (uint32_t i=0; i < desc->audioOuts; ++i)
                    audioOuts[i] = nullptr;
            }

            if (desc->get_parameter_count != nullptr && desc->get_parameter_info != nullptr && desc->get_parameter_value != nullptr && desc->set_parameter_value != nullptr)
            {
                paramCount = desc->get_parameter_count(handle);

                if (paramCount > 0)
                {
                    paramsLast = new float[paramCount];
                    paramsPtr  = new float*[paramCount];
                    paramsOut  = new bool[paramCount];

                    for (uint32_t i=0; i < paramCount; ++i)
                    {
                        paramsLast[i] = desc->get_parameter_value(handle, i);
                        paramsPtr [i] = nullptr;
                        paramsOut [i] = (desc->get_parameter_info(handle, i)->hints & NATIVE_PARAMETER_IS_OUTPUT);
                    }
                }
            }
        }

        void connectPort(const NativePluginDescriptor* const desc, const uint32_t port, void* const dataLocation)
        {
            uint32_t index = 0;

            if (desc->midiIns > 0 || (desc->hints & NATIVE_PLUGIN_USES_TIME) != 0)
            {
                if (port == index++)
                {
                    eventsIn[0] = (LV2_Atom_Sequence*)dataLocation;
                    return;
                }
            }

            for (uint32_t i=1; i < desc->midiIns; ++i)
            {
                if (port == index++)
                {
                    eventsIn[i] = (LV2_Atom_Sequence*)dataLocation;
                    return;
                }
            }

            for (uint32_t i=0; i < desc->midiOuts; ++i)
            {
                if (port == index++)
                {
                    midiOuts[i] = (LV2_Atom_Sequence*)dataLocation;
                    return;
                }
            }

            if (port == index++)
            {
                freewheel = (float*)dataLocation;
                return;
            }

            for (uint32_t i=0; i < desc->audioIns; ++i)
            {
                if (port == index++)
                {
                    audioIns[i] = (float*)dataLocation;
                    return;
                }
            }

            for (uint32_t i=0; i < desc->audioOuts; ++i)
            {
                if (port == index++)
                {
                    audioOuts[i] = (float*)dataLocation;
                    return;
                }
            }

            for (uint32_t i=0; i < paramCount; ++i)
            {
                if (port == index++)
                {
                    paramsPtr[i] = (float*)dataLocation;
                    return;
                }
            }
        }

        CARLA_DECLARE_NON_COPY_STRUCT(Ports);
    } fPorts;

    // -------------------------------------------------------------------

    #define handlePtr ((NativePlugin*)handle)

    static uint32_t host_get_buffer_size(NativeHostHandle handle)
    {
        return handlePtr->fBufferSize;
    }

    static double host_get_sample_rate(NativeHostHandle handle)
    {
        return handlePtr->fSampleRate;
    }

    static bool host_is_offline(NativeHostHandle handle)
    {
        return handlePtr->fIsOffline;
    }

    static const NativeTimeInfo* host_get_time_info(NativeHostHandle handle)
    {
        return &(handlePtr->fTimeInfo);
    }

    static bool host_write_midi_event(NativeHostHandle handle, const NativeMidiEvent* event)
    {
        return handlePtr->handleWriteMidiEvent(event);
    }

    static void host_ui_parameter_changed(NativeHostHandle handle, uint32_t index, float value)
    {
        handlePtr->handleUiParameterChanged(index, value);
    }

    static void host_ui_custom_data_changed(NativeHostHandle handle, const char* key, const char* value)
    {
        handlePtr->handleUiCustomDataChanged(key, value);
    }

    static void host_ui_closed(NativeHostHandle handle)
    {
        handlePtr->handleUiClosed();
    }

    static const char* host_ui_open_file(NativeHostHandle handle, bool isDir, const char* title, const char* filter)
    {
        return handlePtr->handleUiOpenFile(isDir, title, filter);
    }

    static const char* host_ui_save_file(NativeHostHandle handle, bool isDir, const char* title, const char* filter)
    {
        return handlePtr->handleUiSaveFile(isDir, title, filter);
    }

    static intptr_t host_dispatcher(NativeHostHandle handle, NativeHostDispatcherOpcode opcode, int32_t index, intptr_t value, void* ptr, float opt)
    {
        return handlePtr->handleDispatcher(opcode, index, value, ptr, opt);
    }

    #undef handlePtr

    CARLA_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(NativePlugin)
};

// -----------------------------------------------------------------------
// LV2 plugin descriptor functions

static LV2_Handle lv2_instantiate(const LV2_Descriptor* lv2Descriptor, double sampleRate, const char* bundlePath, const LV2_Feature* const* features)
{
    carla_debug("lv2_instantiate(%p, %g, %s, %p)", lv2Descriptor, sampleRate, bundlePath, features);

    const NativePluginDescriptor* pluginDesc  = nullptr;
    const char*                   pluginLabel = nullptr;

    if (std::strncmp(lv2Descriptor->URI, "http://kxstudio.sf.net/carla/plugins/", 37) == 0)
        pluginLabel = lv2Descriptor->URI+37;

    if (pluginLabel == nullptr)
    {
        carla_stderr("Failed to find carla native plugin with URI \"%s\"", lv2Descriptor->URI);
        return nullptr;
    }

    carla_debug("lv2_instantiate() - looking up label \"%s\"", pluginLabel);

    PluginListManager& plm(PluginListManager::getInstance());

    for (LinkedList<const NativePluginDescriptor*>::Itenerator it = plm.descs.begin2(); it.valid(); it.next())
    {
        const NativePluginDescriptor* const& tmpDesc(it.getValue(nullptr));
        CARLA_SAFE_ASSERT_CONTINUE(tmpDesc != nullptr);

        if (std::strcmp(tmpDesc->label, pluginLabel) == 0)
        {
            pluginDesc = tmpDesc;
            break;
        }
    }

    if (pluginDesc == nullptr)
    {
        carla_stderr("Failed to find carla native plugin with label \"%s\"", pluginLabel);
        return nullptr;
    }

    NativePlugin* const plugin(new NativePlugin(pluginDesc, sampleRate, bundlePath, features));

    if (! plugin->init())
    {
        carla_stderr("Failed to init plugin");
        delete plugin;
        return nullptr;
    }

    return (LV2_Handle)plugin;
}

#define instancePtr ((NativePlugin*)instance)

static void lv2_connect_port(LV2_Handle instance, uint32_t port, void* dataLocation)
{
    instancePtr->lv2_connect_port(port, dataLocation);
}

static void lv2_activate(LV2_Handle instance)
{
    carla_debug("lv2_activate(%p)", instance);
    instancePtr->lv2_activate();
}

static void lv2_run(LV2_Handle instance, uint32_t sampleCount)
{
    instancePtr->lv2_run(sampleCount);
}

static void lv2_deactivate(LV2_Handle instance)
{
    carla_debug("lv2_deactivate(%p)", instance);
    instancePtr->lv2_deactivate();
}

static void lv2_cleanup(LV2_Handle instance)
{
    carla_debug("lv2_cleanup(%p)", instance);
    instancePtr->lv2_cleanup();
    delete instancePtr;
}

static uint32_t lv2_get_options(LV2_Handle instance, LV2_Options_Option* options)
{
    carla_debug("lv2_get_options(%p, %p)", instance, options);
    return instancePtr->lv2_get_options(options);
}

static uint32_t lv2_set_options(LV2_Handle instance, const LV2_Options_Option* options)
{
    carla_debug("lv2_set_options(%p, %p)", instance, options);
    return instancePtr->lv2_set_options(options);
}

static const LV2_Program_Descriptor* lv2_get_program(LV2_Handle instance, uint32_t index)
{
    carla_debug("lv2_get_program(%p, %i)", instance, index);
    return instancePtr->lv2_get_program(index);
}

static void lv2_select_program(LV2_Handle instance, uint32_t bank, uint32_t program)
{
    carla_debug("lv2_select_program(%p, %i, %i)", instance, bank, program);
    return instancePtr->lv2_select_program(bank, program);
}

static LV2_State_Status lv2_save(LV2_Handle instance, LV2_State_Store_Function store, LV2_State_Handle handle, uint32_t flags, const LV2_Feature* const* features)
{
    carla_debug("lv2_save(%p, %p, %p, %i, %p)", instance, store, handle, flags, features);
    return instancePtr->lv2_save(store, handle, flags, features);
}

static LV2_State_Status lv2_restore(LV2_Handle instance, LV2_State_Retrieve_Function retrieve, LV2_State_Handle handle, uint32_t flags, const LV2_Feature* const* features)
{
    carla_debug("lv2_restore(%p, %p, %p, %i, %p)", instance, retrieve, handle, flags, features);
    return instancePtr->lv2_restore(retrieve, handle, flags, features);
}

static const void* lv2_extension_data(const char* uri)
{
    carla_debug("lv2_extension_data(\"%s\")", uri);

    static const LV2_Options_Interface  options  = { lv2_get_options, lv2_set_options };
    static const LV2_Programs_Interface programs = { lv2_get_program, lv2_select_program };
    static const LV2_State_Interface    state    = { lv2_save, lv2_restore };

    if (std::strcmp(uri, LV2_OPTIONS__interface) == 0)
        return &options;
    if (std::strcmp(uri, LV2_PROGRAMS__Interface) == 0)
        return &programs;
    if (std::strcmp(uri, LV2_STATE__interface) == 0)
        return &state;

    return nullptr;
}

#undef instancePtr

// -----------------------------------------------------------------------
// LV2 UI descriptor functions

static LV2UI_Handle lv2ui_instantiate(LV2UI_Write_Function writeFunction, LV2UI_Controller controller,
                                      LV2UI_Widget* widget, const LV2_Feature* const* features, const bool isEmbed)
{
    carla_debug("lv2ui_instantiate(..., %p, %p, %p)", writeFunction, controller, widget, features);
#ifndef CARLA_OS_LINUX
    CARLA_SAFE_ASSERT_RETURN(! isEmbed, nullptr);
#endif

    NativePlugin* plugin = nullptr;

    for (int i=0; features[i] != nullptr; ++i)
    {
        if (std::strcmp(features[i]->URI, LV2_INSTANCE_ACCESS_URI) == 0)
        {
            plugin = (NativePlugin*)features[i]->data;
            break;
        }
    }

    if (plugin == nullptr)
    {
        carla_stderr("Host doesn't support instance-access, cannot show UI");
        return nullptr;
    }

    plugin->lv2ui_instantiate(writeFunction, controller, widget, features, isEmbed);

    return (LV2UI_Handle)plugin;
}

#ifdef CARLA_OS_LINUX
static LV2UI_Handle lv2ui_instantiate_embed(const LV2UI_Descriptor*, const char*, const char*,
                                            LV2UI_Write_Function writeFunction, LV2UI_Controller controller,
                                            LV2UI_Widget* widget, const LV2_Feature* const* features)
{
    return lv2ui_instantiate(writeFunction, controller, widget, features, true);
}
#endif

static LV2UI_Handle lv2ui_instantiate_external(const LV2UI_Descriptor*, const char*, const char*,
                                               LV2UI_Write_Function writeFunction, LV2UI_Controller controller,
                                               LV2UI_Widget* widget, const LV2_Feature* const* features)
{
    return lv2ui_instantiate(writeFunction, controller, widget, features, false);
}

#define uiPtr ((NativePlugin*)ui)

static void lv2ui_port_event(LV2UI_Handle ui, uint32_t portIndex, uint32_t bufferSize, uint32_t format, const void* buffer)
{
    carla_debug("lv2ui_port_event(%p, %i, %i, %i, %p)", ui, portIndex, bufferSize, format, buffer);
    uiPtr->lv2ui_port_event(portIndex, bufferSize, format, buffer);
}

static void lv2ui_cleanup(LV2UI_Handle ui)
{
    carla_debug("lv2ui_cleanup(%p)", ui);
    uiPtr->lv2ui_cleanup();
}

static void lv2ui_select_program(LV2UI_Handle ui, uint32_t bank, uint32_t program)
{
    carla_debug("lv2ui_select_program(%p, %i, %i)", ui, bank, program);
    uiPtr->lv2ui_select_program(bank, program);
}

static int lv2ui_idle(LV2UI_Handle ui)
{
    return uiPtr->lv2ui_idle();
}

static int lv2ui_show(LV2UI_Handle ui)
{
    carla_debug("lv2ui_show(%p)", ui);
    return uiPtr->lv2ui_show();
}

static int lv2ui_hide(LV2UI_Handle ui)
{
    carla_debug("lv2ui_hide(%p)", ui);
    return uiPtr->lv2ui_hide();
}

static const void* lv2ui_extension_data(const char* uri)
{
    carla_stdout("lv2ui_extension_data(\"%s\")", uri);

    static const LV2UI_Idle_Interface uiidle = { lv2ui_idle };
    static const LV2UI_Show_Interface uishow = { lv2ui_show, lv2ui_hide };
    static const LV2_Programs_UI_Interface uiprograms = { lv2ui_select_program };

    if (std::strcmp(uri, LV2_UI__idleInterface) == 0)
        return &uiidle;
    if (std::strcmp(uri, LV2_UI__showInterface) == 0)
        return &uishow;
    if (std::strcmp(uri, LV2_PROGRAMS__UIInterface) == 0)
        return &uiprograms;

    return nullptr;
}

#undef uiPtr

// -----------------------------------------------------------------------
// Startup code

CARLA_EXPORT
const LV2_Descriptor* lv2_descriptor(uint32_t index)
{
    carla_debug("lv2_descriptor(%i)", index);

    PluginListManager& plm(PluginListManager::getInstance());

    if (index >= plm.descs.count())
    {
        carla_debug("lv2_descriptor(%i) - out of bounds", index);
        return nullptr;
    }
    if (index < plm.lv2Descs.count())
    {
        carla_debug("lv2_descriptor(%i) - found previously allocated", index);
        return plm.lv2Descs.getAt(index, nullptr);
    }

    const NativePluginDescriptor* const pluginDesc(plm.descs.getAt(index, nullptr));
    CARLA_SAFE_ASSERT_RETURN(pluginDesc != nullptr, nullptr);

    CarlaString tmpURI;
    tmpURI  = "http://kxstudio.sf.net/carla/plugins/";
    tmpURI += pluginDesc->label;

    carla_debug("lv2_descriptor(%i) - not found, allocating new with uri \"%s\"", index, (const char*)tmpURI);

    const LV2_Descriptor lv2DescTmp = {
    /* URI            */ carla_strdup(tmpURI),
    /* instantiate    */ lv2_instantiate,
    /* connect_port   */ lv2_connect_port,
    /* activate       */ lv2_activate,
    /* run            */ lv2_run,
    /* deactivate     */ lv2_deactivate,
    /* cleanup        */ lv2_cleanup,
    /* extension_data */ lv2_extension_data
    };

    LV2_Descriptor* lv2Desc;

    try {
        lv2Desc = new LV2_Descriptor;
    } CARLA_SAFE_EXCEPTION_RETURN("new LV2_Descriptor", nullptr);

    std::memcpy(lv2Desc, &lv2DescTmp, sizeof(LV2_Descriptor));

    plm.lv2Descs.append(lv2Desc);
    return lv2Desc;
}

CARLA_EXPORT
const LV2UI_Descriptor* lv2ui_descriptor(uint32_t index)
{
    carla_debug("lv2ui_descriptor(%i)", index);

#ifdef CARLA_OS_LINUX
    static const LV2UI_Descriptor lv2UiEmbedDesc = {
    /* URI            */ "http://kxstudio.sf.net/carla/ui-embed",
    /* instantiate    */ lv2ui_instantiate_embed,
    /* cleanup        */ lv2ui_cleanup,
    /* port_event     */ lv2ui_port_event,
    /* extension_data */ lv2ui_extension_data
    };

    if (index == 0)
        return &lv2UiEmbedDesc;
    else
        --index;
#endif

    static const LV2UI_Descriptor lv2UiExtDesc = {
    /* URI            */ "http://kxstudio.sf.net/carla/ui-ext",
    /* instantiate    */ lv2ui_instantiate_external,
    /* cleanup        */ lv2ui_cleanup,
    /* port_event     */ lv2ui_port_event,
    /* extension_data */ lv2ui_extension_data
    };

    return (index == 0) ? &lv2UiExtDesc : nullptr;
}

// -----------------------------------------------------------------------