// native_bridge/include/FxRealtimeIPC.h
// SHM layout cho fx_vst_bridge --realtime-fx (VST FX xử lý realtime, cloud-FX
// loop): engine (Python) tạo mapping, bridge mở và chạy vòng lặp audio.
// Tất cả field u32/float (4-byte) — KHÔNG padding — mirror chính xác bằng
// ctypes trong app/core/fx_realtime.py.
#pragma once
#include <cstdint>

#define FXRT_MAGIC 0x46585254u      // "FXRT"
#define FXRT_BLOCK 256
#define FXRT_IN_SLOTS 4             // engine -> bridge
#define FXRT_OUT_SLOTS 8            // bridge -> engine
#define FXRT_STATE_STARTING 0
#define FXRT_STATE_READY 1
#define FXRT_STATE_ERROR 2

// Header 48 bytes (12 u32) — giữ thứ tự khớp fx_realtime.py.
struct FxRealtimeHeader {
    volatile uint32_t magic;
    volatile uint32_t state;
    uint32_t sampleRate;
    uint32_t blockSize;
    volatile uint32_t running;      // engine set 0 → bridge thoát
    volatile uint32_t heartbeat;    // bridge tăng mỗi 100ms (watchdog)
    volatile uint32_t inWrite;      // producer: engine
    volatile uint32_t inRead;       // consumer: bridge
    uint32_t inSlots;
    volatile uint32_t outWrite;     // producer: bridge
    volatile uint32_t outRead;      // consumer: engine
    uint32_t outSlots;
};

struct FxRealtimeIPC {
    FxRealtimeHeader h;
    float inL[FXRT_IN_SLOTS][FXRT_BLOCK];
    float inR[FXRT_IN_SLOTS][FXRT_BLOCK];
    float outL[FXRT_OUT_SLOTS][FXRT_BLOCK];
    float outR[FXRT_OUT_SLOTS][FXRT_BLOCK];
};