clap_osc.cpp

namespace sst::osc_adapter
{
struct OSCAdapter
{
    OSCAdapter(const clap_plugin *p); // bind to this plugin
    const clap_input_events *getInputEventQueue() { return eventList.clapInputEvents(); }
    clap_output_events *getOutputEventQueue(); // auto thread event queue

    void startWith(uint32_t inputPort, uint32_t outputPort)
    {
        oscThreadShouldStop = false;
        oscThread =
            std::make_unique<std::thread>([=, this]() { runOscThread(inputPort, outputPort); });
    }
    void stop()
    {
        oscThreadShouldStop = true;
        if (oscThread)
        {
            oscThread->join();
            oscThread = nullptr;
        }
    }
    void runOscThread(uint32_t inputPort, uint32_t outputPort)
    {
        using namespace oscpkt;
        UdpSocket sock;
        sock.bindTo(inputPort);
        if (!sock.isOk())
        {
            std::cout << "Error opening port " << inputPort << ": " << sock.errorMessage() << "\n";
            return;
        }

        std::cout << "Server started, will listen to packets on port " << inputPort << std::endl;
        PacketReader pr;
        PacketWriter pw;

        while (!oscThreadShouldStop)
        {
            if (!sock.isOk())
            {
                break;
            }

            if (sock.receiveNextPacket(30))
            {
                pr.init(sock.packetData(), sock.packetSize());
                oscpkt::Message *msg = nullptr;
                while (pr.isOk() && (msg = pr.popMessage()) != nullptr)
                {
                    int64_t iarg0 = CLAP_INVALID_ID;
                    double darg0 = 0.0;
                    if (msg->match("/set_parameter")
                            .popInt64(iarg0)
                            .popDouble(darg0)
                            .isOkNoMoreArgs())
                    {
                        // constructing clap events like this is a bit verbose,
                        // will probably want some kind of abstraction for this
                        clap_event_param_value pev;
                        pev.header.flags = 0;
                        pev.header.size = sizeof(clap_event_param_value);
                        pev.header.space_id = CLAP_CORE_EVENT_SPACE_ID;
                        pev.header.time = 0;
                        pev.header.type = CLAP_EVENT_PARAM_VALUE;
                        pev.cookie = nullptr; // to be nice, should implement this properly
                        pev.channel = -1;
                        pev.port_index = -1;
                        pev.key = -1;
                        pev.param_id = iarg0;
                        pev.value = darg0;
                        eventList.push((const clap_event_header *)&pev);
                    }
                }
            }
        }
    }
    std::unique_ptr<std::thread> oscThread;
    std::atomic<bool> oscThreadShouldStop{false};
    clap::helpers::EventList eventList;
};
} // namespace sst::osc_adapter