feat: open native VST FX GUI from mastering panel + FX rack (bridge --open-fx-gui)

app/api/v1/plugins.py

@@ -499,6 +499,12 @@ class OpenInCarlaRequest(BaseModel):
     plugin_path: Optional[str] = None
 
 
+class FxGuiRequest(BaseModel):
+    """Mở native GUI của VST FX qua bridge (Windows desktop)."""
+    path: str
+    name: Optional[str] = None
+
+
 class PreviewRequest(BaseModel):
     """Quick-render preview: pedalboard render clip ngắn bằng ĐÚNG plugin +
     preset (cùng code path với export) → trả wav để browser phát.
@@ -677,6 +683,66 @@ async def open_in_carla(req: OpenInCarlaRequest, current_user: dict = Depends(ge
     except Exception as e:
         raise HTTPException(status_code=500, detail=f"Không mở được Carla: {e}")
 
+@router.post("/fx-gui")
+async def open_fx_gui(req: FxGuiRequest, current_user: dict = Depends(get_current_user)):
+    """Mở native GUI của VST FX (mastering chain / FX rack) qua bridge.
+
+    Bridge có mode `--open-fx-gui <job.json>` (Windows): spawn tiến trình riêng
+    giữ vòng lặp message pump, tạo window 800x600 + attach IPlugView của plugin.
+    Đây là GUI tách rời — user chỉnh thông số, đóng window là bridge thoát
+    (exit 0). Không spawn 2 lần cho cùng plugin đang mở (tránh trùng GUI).
+    """
+    enforce_password_changed(current_user)
+    from app.core.native_render import find_bridge_exe
+    exe = find_bridge_exe()
+    if not exe:
+        raise HTTPException(
+            status_code=409,
+            detail="Không tìm thấy bridge native (daw_vst_bridge.exe). "
+                   "Hãy chạy bản desktop đã build đầy đủ.",
+        )
+    plugin_path = (req.path or "").strip()
+    if not plugin_path:
+        raise HTTPException(status_code=400, detail="Thiếu đường dẫn VST plugin.")
+    # Tránh mở 2 GUI cùng plugin: nếu tiến trình bridge fx-gui cho plugin này
+    # đang chạy → trả started=False (frontend có thể focus window cũ).
+    for proc in _FX_GUI_PROCESSES:
+        if proc is not None and proc.poll() is None and getattr(proc, "_sf_plugin_path", None) == plugin_path:
+            return {"success": True, "started": False, "already_running": True, "cmd": []}
+    job = {"path": plugin_path, "name": req.name or os.path.basename(plugin_path)}
+    fd, job_path = tempfile.mkstemp(prefix="sf_fx_gui_", suffix=".json", dir=tempfile.gettempdir())
+    try:
+        with os.fdopen(fd, "w", encoding="utf-8") as f:
+            json.dump(job, f)
+    except Exception:
+        os.close(fd)
+        raise HTTPException(status_code=500, detail="Không ghi được job file cho bridge.")
+    cmd = [exe, "--open-fx-gui", job_path]
+    try:
+        proc = subprocess.Popen(cmd, close_fds=os.name != "nt")
+        proc._sf_plugin_path = plugin_path
+        _register_fx_gui_process(proc)
+        return {"success": True, "started": True, "already_running": False, "cmd": cmd}
+    except Exception as e:
+        try:
+            os.remove(job_path)
+        except Exception:
+            pass
+        raise HTTPException(status_code=500, detail=f"Không mở được GUI của VST: {e}")
+
+
+_FX_GUI_PROCESSES = []  # list[subprocess.Popen] — các bridge fx-gui do app spawn
+
+def _register_fx_gui_process(proc):
+    global _FX_GUI_PROCESSES
+    _prune_fx_gui_processes()
+    _FX_GUI_PROCESSES.append(proc)
+
+def _prune_fx_gui_processes():
+    global _FX_GUI_PROCESSES
+    _FX_GUI_PROCESSES = [p for p in _FX_GUI_PROCESSES if p is not None and p.poll() is None]
+
+
 
 # ── Carla bridge lifecycle ─────────────────────────────────────────────────
 # App spawn Carla (open_in_carla) và PHẢI có khả năng dừng nó khi track chuyển

app/static/js/app.jsx

@@ -11754,7 +11754,7 @@ const ExportModal = ({ open, onClose, exportSettings, setExportSettings, isExpor
   );
 };
 
-  const vstRow = (s, idx, toggleV, changeV, uploadV, moveV, removeV, fxl, chainLen) => (
+  const vstRow = (s, idx, toggleV, changeV, uploadV, moveV, removeV, fxl, chainLen, openGui) => (
     <div key={idx} className="flex items-center gap-2 bg-slate-900/60 border border-slate-800 rounded-lg px-2 py-1.5 flex-wrap">
       <button onClick={() => toggleV(idx)} className={`w-4 h-4 rounded-full flex items-center justify-center text-[9px] font-bold shrink-0 ${!s.bypass ? 'bg-teal-500 text-slate-950' : 'bg-slate-700 text-slate-300'}`} title={s.bypass ? 'Bypass' : 'Active'}>
         <i data-lucide="power" className="w-2.5 h-2.5"></i>
@@ -11766,6 +11766,7 @@ const ExportModal = ({ open, onClose, exportSettings, setExportSettings, isExpor
       </select>
       <span className={`text-[9px] font-mono ${s.preset_b64 ? 'text-emerald-400' : 'text-slate-600'}`}>{s.preset_b64 ? '✓ preset' : 'no preset'}</span>
       <button onClick={() => uploadV(idx)} className="px-2 py-1 bg-slate-800 hover:bg-slate-700 text-slate-300 text-[10px] font-semibold rounded transition" title="Upload .vstpreset xuất từ Carla (Save preset)">Preset</button>
+      {openGui && <button onClick={() => openGui(s)} disabled={!s.path} className="px-2 py-1 bg-violet-800 hover:bg-violet-700 disabled:opacity-30 text-violet-100 text-[10px] font-semibold rounded transition" title="Mở GUI của VST (chỉnh thông số trực tiếp)"><i data-lucide="monitor" className="w-3 h-3"></i> GUI</button>}
       <button onClick={() => { if (!s.path) { window.showToast && window.showToast('Chọn VST FX trước', 'warning'); return; } window.SonicAPI.openInCarla(s.name || s.path, s.path).then(r => { if (r && r.success) window.showToast && window.showToast('Đã mở Carla với ' + (s.name || s.path) + ' — chỉnh âm trong Carla rồi Save preset', 'success'); else window.showToast && window.showToast('Không mở được Carla', 'error'); }).catch(err => window.showToast && window.showToast('Lỗi mở Carla: ' + (err.message || err), 'error')); }} className="px-2 py-1 bg-teal-800 hover:bg-teal-700 text-teal-100 text-[10px] font-semibold rounded transition" title="Mở native GUI trong Carla">Carla</button>
       <button onClick={() => moveV(idx, -1)} disabled={idx === 0} className="w-6 h-6 bg-slate-800 hover:bg-slate-700 text-slate-300 rounded text-xs disabled:opacity-30" title="Lên"><i data-lucide="chevron-up" className="w-3 h-3"></i></button>
       <button onClick={() => moveV(idx, 1)} disabled={idx === chainLen - 1} className="w-6 h-6 bg-slate-800 hover:bg-slate-700 text-slate-300 rounded text-xs disabled:opacity-30" title="Xuống"><i data-lucide="chevron-down" className="w-3 h-3"></i></button>
@@ -11817,7 +11818,9 @@ const FXRackModal = ({ track, onUpdateTrack, onClose }) => {
   const toggleVst = (idx) => setVstChain(vstChain.map((s, i) => i === idx ? { ...s, bypass: !s.bypass } : s));
   const removeVst = (idx) => setVstChain(vstChain.filter((_, i) => i !== idx));
   const moveVst = (idx, dir) => { const j = idx + dir; if (j < 0 || j >= vstChain.length) return; const next = [...vstChain]; const mv = next.splice(idx, 1)[0]; next.splice(j, 0, mv); setVstChain(next); };
-  const addVst = (path) => { const fx = (fxList || []).find(f => f.path === path); if (!fx) return; setVstChain([...vstChain, { type: 'vst3', path: fx.path, name: fx.name || fx.id, preset_b64: '', bypass: false }]); };
+  const openVstGui = (s) => { if (!s || !s.path) { window.showToast && window.showToast('Chọn VST FX trước', 'warning'); return; } if (!window.SonicAPI || !window.SonicAPI.openFxGui) { window.showToast && window.showToast('Máy này không hỗ trợ mở GUI VST', 'warning'); return; } window.SonicAPI.openFxGui({ path: s.path, name: s.name || s.path }).then(r => { if (r && r.success) window.showToast && window.showToast('Đã mở GUI của ' + (s.name || s.path) + ' — chỉnh xong đóng cửa sổ plugin', 'success'); else if (r && r.already_running) window.showToast && window.showToast('GUI của plugin này đang mở sẵn', 'info'); else window.showToast && window.showToast('Không mở được GUI', 'error'); }).catch(err => window.showToast && window.showToast('Lỗi mở GUI: ' + (err.message || err), 'error')); };
+const addVst = (path) => { const fx = (fxList || []).find(f => f.path === path); if (!fx) return; setVstChain([...vstChain, { type: 'vst3', path: fx.path, name: fx.name || fx.id, preset_b64: '', bypass: false }]);
+    openVstGui({ path: fx.path, name: fx.name || fx.id }); };
   const changeVstPlugin = (idx, path) => { const fx = (fxList || []).find(f => f.path === path); setVstChain(vstChain.map((s, i) => i === idx ? { ...s, path, name: fx ? (fx.name || fx.id) : s.name, preset_b64: '' } : s)); };
   const uploadVstPreset = (idx) => {
     const inp = document.createElement('input');
@@ -12138,7 +12141,7 @@ const FXRackModal = ({ track, onUpdateTrack, onClose }) => {
             </div>
           </div>
           {vstChain.length === 0 && <div className="text-[10px] text-slate-500 font-mono">Chưa có VST FX — chọn plugin bên dưới để thêm vào insert chain (WebAudio chain → VST FX → Fader).</div>}
-          {vstChain.map((s, idx) => vstRow(s, idx, toggleVst, changeVstPlugin, uploadVstPreset, moveVst, removeVst, fxList, vstChain.length))}
+          {vstChain.map((s, idx) => vstRow(s, idx, toggleVst, changeVstPlugin, uploadVstPreset, moveVst, removeVst, fxList, vstChain.length, openVstGui))}
           <select value={addVstSel} onChange={e => { setAddVstSel(e.target.value); if (e.target.value) { addVst(e.target.value); setAddVstSel(''); } }} className="w-full bg-slate-950 border border-dashed border-slate-700 hover:border-teal-600 text-teal-300 rounded px-2 py-1.5 text-[11px] outline-none" title="Thêm VST FX">
             <option value="">+ Thêm VST FX...</option>
             {(fxList || []).map(f => <option key={f.path} value={f.path}>{f.name || f.id}</option>)}
@@ -12375,7 +12378,9 @@ const MasteringModal = ({ isOpen, onClose, masteringSettings, setMasteringSettin
   const toggleMasterVst = (idx) => setMasterVstChain(masterVstChain.map((s, i) => i === idx ? { ...s, bypass: !s.bypass } : s));
   const removeMasterVst = (idx) => setMasterVstChain(masterVstChain.filter((_, i) => i !== idx));
   const moveMasterVst = (idx, dir) => { const j = idx + dir; if (j < 0 || j >= masterVstChain.length) return; const next = [...masterVstChain]; const mv = next.splice(idx, 1)[0]; next.splice(j, 0, mv); setMasterVstChain(next); };
-  const addMasterVst = (path) => { const fx = (masterFxList || []).find(f => f.path === path); if (!fx) return; setMasterVstChain([...masterVstChain, { type: 'vst3', path: fx.path, name: fx.name || fx.id, preset_b64: '', bypass: false }]); };
+  const openMasterVstGui = (s) => { if (!s || !s.path) { window.showToast && window.showToast('Chọn VST FX trước', 'warning'); return; } if (!window.SonicAPI || !window.SonicAPI.openFxGui) { window.showToast && window.showToast('Máy này không hỗ trợ mở GUI VST', 'warning'); return; } window.SonicAPI.openFxGui({ path: s.path, name: s.name || s.path }).then(r => { if (r && r.success) window.showToast && window.showToast('Đã mở GUI của ' + (s.name || s.path) + ' — chỉnh xong đóng cửa sổ plugin', 'success'); else if (r && r.already_running) window.showToast && window.showToast('GUI của plugin này đang mở sẵn', 'info'); else window.showToast && window.showToast('Không mở được GUI', 'error'); }).catch(err => window.showToast && window.showToast('Lỗi mở GUI: ' + (err.message || err), 'error')); };
+const addMasterVst = (path) => { const fx = (masterFxList || []).find(f => f.path === path); if (!fx) return; setMasterVstChain([...masterVstChain, { type: 'vst3', path: fx.path, name: fx.name || fx.id, preset_b64: '', bypass: false }]);
+    openMasterVstGui({ path: fx.path, name: fx.name || fx.id }); };
   const changeMasterVstPlugin = (idx, path) => { const fx = (masterFxList || []).find(f => f.path === path); setMasterVstChain(masterVstChain.map((s, i) => i === idx ? { ...s, path, name: fx ? (fx.name || fx.id) : s.name, preset_b64: '' } : s)); };
   const uploadMasterVstPreset = (idx) => {
     const inp = document.createElement('input');
@@ -13143,7 +13148,7 @@ const MasteringModal = ({ isOpen, onClose, masteringSettings, setMasteringSettin
             </div>
           </div>
           {masterVstChain.length === 0 && <div className="text-[10px] text-slate-500 oz-font-mono">Chưa có VST FX masterbus — chọn plugin bên dưới (Ozone...) để chạy chain sau khi mix WebAudio.</div>}
-          {masterVstChain.map((s, idx) => vstRow(s, idx, toggleMasterVst, changeMasterVstPlugin, uploadMasterVstPreset, moveMasterVst, removeMasterVst, masterFxList, masterVstChain.length))}
+          {masterVstChain.map((s, idx) => vstRow(s, idx, toggleMasterVst, changeMasterVstPlugin, uploadMasterVstPreset, moveMasterVst, removeMasterVst, masterFxList, masterVstChain.length, openMasterVstGui))}
           <select value={addMasterVstSel} onChange={e => { setAddMasterVstSel(e.target.value); if (e.target.value) { addMasterVst(e.target.value); setAddMasterVstSel(''); } }} className="w-full bg-slate-950 border border-dashed border-slate-700 hover:border-teal-600 text-teal-300 rounded px-2 py-1.5 text-[11px] outline-none" title="Thêm VST FX">
             <option value="">+ Thêm VST FX...</option>
             {(masterFxList || []).map(f => <option key={f.path} value={f.path}>{f.name || f.id}</option>)}

app/static/js/services/api.js

@@ -92,6 +92,8 @@ window.API_BASE_URL = (window.API_BASE_URL || window.location.origin).replace(/\
         midiRender: (payload) => apiRequest('/api/v1/plugins/midi-render', { method: 'POST', body: JSON.stringify(payload) }),
         listFx: () => apiRequest('/api/v1/plugins/fx', { method: 'GET' }),
         fxRender: (payload) => apiRequest('/api/v1/plugins/fx-render', { method: 'POST', body: JSON.stringify(payload) }),
+        // Mở native GUI của VST FX (mastering chain / FX rack) qua bridge
+        openFxGui: (payload) => apiRequest('/api/v1/plugins/fx-gui', { method: 'POST', body: JSON.stringify(payload) }),
         soundfontRender: (payload) => apiRequest('/api/v1/plugins/soundfont-render', { method: 'POST', body: JSON.stringify(payload) }),
         // Phát dãy MIDI notes realtime qua Carla bridge (OSC) — preview khi
         // pedalboard không render được plugin (VD VST2)

native_bridge/include/RenderFxJob.h

@@ -36,4 +36,12 @@ int run_render_fx_job(const std::string& jobPath, const std::string& inPath,
 // crashes the module loader is skipped, not fatal).
 int run_scan_dir(const std::string& dirPath);
 
+// GUI mode (Mastering/FX Rack → "mở VST GUI"): `daw_vst_bridge --open-fx-gui
+// <job.json>` loads ONE VST3 effect plugin, opens its native editor window and
+// runs a message loop until the user closes the window (WM_DESTROY), then
+// detaches the view and exits 0. job.json: { "path": "...", "name": "..." }.
+// Windows only. Exit codes: 0 ok, 1 job/argument error, 2 plugin load or
+// editor attach failure.
+int run_open_fx_gui(const std::string& jobPath);
+
 #endif // RENDER_FX_JOB_H

native_bridge/src/RenderFxJob.cpp

@@ -23,6 +23,7 @@
 #include "pluginterfaces/vst/ivsteditcontroller.h"
 #include "pluginterfaces/vst/ivstprocesscontext.h"
 #include "pluginterfaces/vst/ivstmessage.h"
+#include "pluginterfaces/gui/iplugview.h"
 #endif
 
 #ifdef _WIN32
@@ -318,6 +319,24 @@ public:
     tresult restartComponent(Steinberg::int32) override { return kResultOk; }
 };
 
+using Steinberg::IPlugView;
+using Steinberg::kPlatformTypeHWND;
+
+// Minimal IPlugFrame so the plugin can resize its editor view.
+class HostPlugFrameFx : public Steinberg::IPlugFrame {
+public:
+    tresult queryInterface(const char*, void** v) override {
+        *v = nullptr;
+        return kNoInterface;
+    }
+    Steinberg::uint32 addRef() override { return 1; }
+    Steinberg::uint32 release() override { return 1; }
+    tresult resizeView(Steinberg::IPlugView* view, Steinberg::ViewRect* newSize) override {
+        if (view && newSize) view->onSize(newSize);
+        return kResultOk;
+    }
+};
+
 struct Vst3FxState {
     VST3::Hosting::Module::Ptr module;  // destroyed LAST (owns the factory)
     IPtr<IComponent> component;
@@ -329,6 +348,8 @@ struct Vst3FxState {
     int32 inputChannels = 2;
     int32 outputChannels = 2;
     bool controllerIsComponent = false;
+    Steinberg::IPlugFrame* plugFrame = nullptr;  // owned; freed in closeEditor
+    IPtr<IPlugView> view;                        // editor view while GUI open
 };
 
 // Class selection for FX: any kVstAudioEffectClass whose subcategory does NOT
@@ -590,6 +611,80 @@ public:
         std::cout << "[RenderFx] preset applied component=" << comp.size()
                   << " controller=" << ctrl.size() << std::endl;
         return true;
+#endif
+    }
+    // Native editor: attach the plugin's IPlugView to a host window (must run
+    // on the thread that will pump its messages — same rule as Vst3Instrument).
+    bool openEditor(void* parentWindowHandle) {
+#ifndef HAVE_VST3SDK
+        (void)parentWindowHandle;
+        return false;
+#else
+        auto* s = static_cast<Vst3FxState*>(state_);
+        if (!s || !s->controller || !parentWindowHandle) return false;
+        if (s->plugFrame) return true;  // already attached
+        s->plugFrame = new HostPlugFrameFx();
+        IPlugView* rawView = nullptr;
+        s->controller->queryInterface(IPlugView::iid, (void**)&rawView);
+        FUnknownPtr<IPlugView> view(rawView);
+        if (!view) {
+            // Some plugins expose IPlugView on the component instead.
+            IPlugView* rawViewC = nullptr;
+            s->component->queryInterface(IPlugView::iid, (void**)&rawViewC);
+            view = FUnknownPtr<IPlugView>(rawViewC);
+        }
+        if (!view) {
+            // Official editorhost.cpp pattern: IEditController::createView.
+            // JUCE-based plugins (Scaler2) expose the editor only this way.
+            view = owned(s->controller->createView(Steinberg::Vst::ViewType::kEditor));
+        }
+        if (!view) {
+            delete s->plugFrame;
+            s->plugFrame = nullptr;
+            return false;
+        }
+        view->setFrame(s->plugFrame);
+        view->isPlatformTypeSupported(kPlatformTypeHWND);
+        if (view->attached(parentWindowHandle, kPlatformTypeHWND) != kResultOk) {
+            view->setFrame(nullptr);
+            delete s->plugFrame;
+            s->plugFrame = nullptr;
+            return false;
+        }
+        s->view = view;
+#ifdef _WIN32
+        HWND hwnd = (HWND)parentWindowHandle;
+        Steinberg::ViewRect rect;
+        if (view->getSize(&rect) == kResultOk) {
+            int w = rect.right - rect.left;
+            int h = rect.bottom - rect.top;
+            RECT r = { 0, 0, w, h };
+            AdjustWindowRect(&r, WS_OVERLAPPEDWINDOW, FALSE);
+            SetWindowPos(hwnd, nullptr, 0, 0, r.right - r.left, r.bottom - r.top,
+                         SWP_NOMOVE | SWP_NOZORDER | SWP_NOACTIVATE);
+            view->onSize(&rect);  // some Skia/OpenGL editors skip first paint
+        }
+#endif
+        return true;
+#endif
+    }
+    // Detach editor. Must run on the SAME thread that attached (the GUI message
+    // loop has exited). removed() is intentionally NOT called — Vst3Instrument
+    // documents a deadlock when the pump is not running.
+    void closeEditor() {
+#ifndef HAVE_VST3SDK
+        return;
+#else
+        auto* s = static_cast<Vst3FxState*>(state_);
+        if (!s) return;
+        if (s->view) {
+            s->view->setFrame(nullptr);
+            s->view = nullptr;  // IPtr releases the view
+        }
+        if (s->plugFrame) {
+            delete s->plugFrame;
+            s->plugFrame = nullptr;
+        }
 #endif
     }
     bool loaded() const { return state_ != nullptr; }
@@ -791,6 +886,125 @@ int run_render_fx_job(const std::string& jobPath, const std::string& inPath,
     return rc;
 }
 
+// --- --open-fx-gui <job.json>: native editor window for one VST3 FX ----------
+#ifdef _WIN32
+namespace {
+
+const char* kFxGuiWndClass = "SonicForge_FX_GUI_Class";
+
+struct FxGuiCtx {
+    bool closing = false;
+};
+
+LRESULT CALLBACK FxGuiWndProc(HWND hwnd, UINT msg, WPARAM wp, LPARAM lp) {
+    FxGuiCtx* ctx = (FxGuiCtx*)GetWindowLongPtrA(hwnd, GWLP_USERDATA);
+    switch (msg) {
+        case WM_CLOSE:
+            DestroyWindow(hwnd);
+            return 0;
+        case WM_DESTROY:
+            if (ctx) ctx->closing = true;
+            return 0;
+        default:
+            return DefWindowProcA(hwnd, msg, wp, lp);
+    }
+}
+
+}  // namespace
+
+// SEH frames hold only raw pointers / trivials (C2712 — no unwinding locals).
+static bool fxGuiAttachSafe(void* fx, HWND hwnd) {
+#ifdef HAVE_VST3SDK
+    __try { return static_cast<Vst3Fx*>(fx)->openEditor(hwnd); }
+    __except (EXCEPTION_EXECUTE_HANDLER) { return false; }
+#else
+    (void)fx; (void)hwnd;
+    return false;
+#endif
+}
+static void fxGuiDetachSafe(void* fx) {
+#ifdef HAVE_VST3SDK
+    __try { static_cast<Vst3Fx*>(fx)->closeEditor(); }
+    __except (EXCEPTION_EXECUTE_HANDLER) {}
+#else
+    (void)fx;
+#endif
+}
+
+int run_open_fx_gui(const std::string& jobPath) {
+    // The editor window and its message pump live on this (STA) thread for the
+    // whole GUI session — VST3 editors need the COM apartment + pump together.
+    CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED);
+    struct ComGuard { ~ComGuard() { CoUninitialize(); } } comGuard;
+
+    // 1. Parse job { path, name }.
+    std::ifstream jf(jobPath, std::ios::binary);
+    if (!jf) { std::cerr << "[FxGui] cannot read job file: " << jobPath << std::endl; return 1; }
+    std::string data((std::istreambuf_iterator<char>(jf)), std::istreambuf_iterator<char>());
+    json_parse_result_s pres = {};
+    json_value_s* root = json_parse_ex(data.data(), data.size(), json_parse_flags_default,
+                                       nullptr, nullptr, &pres);
+    if (!root) { std::cerr << "[FxGui] job JSON parse error (code " << std::to_string(pres.error) << ")" << std::endl; return 1; }
+    struct RootHolder { json_value_s* p = nullptr; ~RootHolder() { if (p) std::free(p); } } rootH;
+    rootH.p = root;
+    if (root->type != json_type_object) { std::cerr << "[FxGui] job root must be a JSON object" << std::endl; return 1; }
+    const json_object_s* job = static_cast<const json_object_s*>(root->payload);
+    const std::string path = memberString(job, "path", "");
+    const std::string name = memberString(job, "name", "");
+    if (path.empty()) { std::cerr << "[FxGui] job missing path" << std::endl; return 1; }
+
+    // 2. Load the plugin (fixed 44.1k/512 — GUI only, no audio processed here).
+    Vst3Fx fx;
+    if (!fx.load(path, 44100.0, 512)) { std::cerr << "[FxGui] plugin load failed: " << path << std::endl; return 2; }
+
+    // 3. Host window.
+    WNDCLASSA wc = {};
+    wc.lpfnWndProc = FxGuiWndProc;
+    wc.hInstance = GetModuleHandleA(nullptr);
+    wc.lpszClassName = kFxGuiWndClass;
+    RegisterClassA(&wc);
+    FxGuiCtx ctx;
+    HWND hwnd = CreateWindowExA(0, kFxGuiWndClass,
+                                (name.empty() ? "VST FX" : name).c_str(),
+                                WS_OVERLAPPEDWINDOW | WS_VISIBLE | WS_CLIPCHILDREN | WS_CLIPSIBLINGS,
+                                CW_USEDEFAULT, CW_USEDEFAULT, 800, 600,
+                                nullptr, nullptr, GetModuleHandleA(nullptr), nullptr);
+    if (!hwnd) { std::cerr << "[FxGui] create window failed" << std::endl; return 1; }
+    SetWindowLongPtrA(hwnd, GWLP_USERDATA, (LONG_PTR)&ctx);
+
+    // 4. Attach the plugin editor (SEH-guarded — plugin GUI code may crash).
+    if (!fxGuiAttachSafe(&fx, hwnd)) {
+        std::cerr << "[FxGui] editor attach failed for " << path << std::endl;
+        DestroyWindow(hwnd);
+        return 2;
+    }
+    std::cout << "[FxGui] editor open: " << (name.empty() ? path : name) << std::endl;
+
+    // 5. Pump messages until the window is destroyed.
+    MSG msg;
+    while (!ctx.closing) {
+        BOOL r = GetMessageA(&msg, nullptr, 0, 0);
+        if (r <= 0) break;
+        TranslateMessage(&msg);
+        DispatchMessageA(&msg);
+    }
+
+    // 6. Detach + exit.
+    fxGuiDetachSafe(&fx);
+    std::cout << "[FxGui] editor closed" << std::endl;
+    return 0;
+}
+
+#else  // !_WIN32
+
+int run_open_fx_gui(const std::string& jobPath) {
+    (void)jobPath;
+    std::cerr << "[FxGui] GUI mode chỉ hỗ trợ Windows" << std::endl;
+    return 1;
+}
+
+#endif  // _WIN32
+
 // --- --scan: classify VST3 modules as instrument/effect ----------------------
 namespace {
 

native_bridge/src/main.cpp

@@ -638,6 +638,14 @@ int main(int argc, char* argv[]) {
     }
     if (!scanDir.empty()) return run_scan_dir(scanDir);
 
+    // --open-fx-gui <job.json>: one-shot native editor window for a VST3 FX
+    // (Mastering/FX Rack → "mở VST GUI"); runs until the user closes it.
+    std::string fxGuiJob;
+    for (int i = 1; i + 1 < argc; ++i) {
+        if (std::strcmp(argv[i], "--open-fx-gui") == 0) fxGuiJob = argv[i + 1];
+    }
+    if (!fxGuiJob.empty()) return run_open_fx_gui(fxGuiJob);
+
     // 1. Shared memory name: argv --shm <name> | env SF_SHM_NAME | default
     std::string shmName = "SonicForge_DAW_IPC";
     for (int i = 1; i + 1 < argc; ++i) {