// native_bridge/include/SandboxVst3Host.h
// G4.2: VST3 instrument hosted in a CHILD PROCESS (plugin_host.exe). The
// plugin's crash kills only the child; this host mutes the channel, respawns
// the child, and the bridge + other channels keep running. MIDI flows bridge
// -> child SHM (midiQueue), audio flows child -> bridge (masterLeft/Right).
#ifndef SANDBOX_VST3_HOST_H
#define SANDBOX_VST3_HOST_H

#include "INativeInstrument.h"
#include "SharedMemoryIPC.h"

#include <atomic>
#include <string>
#include <thread>

#ifdef _WIN32
#include <windows.h>
#endif

class SandboxVst3Host : public INativeInstrument {
public:
    SandboxVst3Host();
    ~SandboxVst3Host() override;

    bool loadPlugin(const std::string& path, double sampleRate, uint32_t channel);

    bool init(double sampleRate, uint32_t maxBlockSize) override;
    void selectProgram(uint32_t channel, uint32_t bank, uint32_t program) override {}
    void noteOn(uint32_t channel, uint32_t pitch, float velocity, uint32_t sampleOffset) override;
    void noteOff(uint32_t channel, uint32_t pitch, uint32_t sampleOffset) override;
    void controlChange(uint32_t channel, uint32_t cc, uint32_t value) override;
    void programChange(uint32_t channel, uint32_t program) override;
    void pitchBend(uint32_t channel, uint32_t bend14) override;
    // The child owns its GUI window (plugin_host opens it on its main thread).
    bool openGUI(void* parentWindowHandle) override { (void)parentWindowHandle; return true; }
    void closeGUI() override {}  // child window dies with the child process
    void processAudioBlock(float* outputL, float* outputR, uint32_t numSamples) override;

private:
    bool spawnChild();
    void watchdogLoop();

    std::string path_;
    std::string shmName_;
    double sampleRate_ = 44100.0;
    uint32_t block_ = AUDIO_BLOCK_SIZE;
    uint32_t channel_ = 0;
    ShmHandle* shm_ = nullptr;
    SandboxHostIPC* ipc_ = nullptr;
    std::atomic<bool> alive_{false};
    std::atomic<bool> stop_{false};
    std::thread watchdog_;
#ifdef _WIN32
    HANDLE childProc_ = nullptr;
#endif
};

#endif // SANDBOX_VST3_HOST_H