fix GUI VSTi khi PLAY: defer OPEN_GUI + silence same-path truoc attach (G0.1)

native_bridge/src/main.cpp

@@ -956,6 +956,19 @@ int main(int argc, char* argv[]) {
                 return;
             }
         }
+        // G0.1 (BUG_REPORT): mo GUI khi dang PLAY -> attachView chay tren worker
+        // thread trong luc audio loop process() cung DLL (2 thread 1 plugin) ->
+        // Nexus throw (createView/attached) -> GUI khong load + retry spam ->
+        // stall 3s -> watchdog kill bridge -> mat het instrument -> cam. Defer
+        // OPEN_GUI toi khi transport STOP (sweep duoi fulfill khi loaded &&
+        // transportStopped). Khong doi: tranh mat am; user STOP la GUI tu mo.
+        if (!transportStopped) {
+            std::cerr << "[NativeBridge] GUI deferred ch=" << guiCh
+                      << " plugin=" << pluginId << " (transport PLAY) - queued" << std::endl;
+            std::lock_guard<std::mutex> lock(g_pendingGuiMutex);
+            g_pendingGui[guiCh] = { (void*)arg1, pluginId };
+            return;
+        }
         if (!workers[guiCh]) {
             workers[guiCh] = std::make_unique<ChannelWorker>();
         }
@@ -994,6 +1007,28 @@ int main(int argc, char* argv[]) {
             }
         }
 #endif
+        // G0.1b: silence same-path instances on the MAIN thread BEFORE the
+        // attach job runs - renderAll of this loop iteration (and any before
+        // the worker sets reloading_) would otherwise process() another Nexus
+        // while the job's reload() (createInstance/terminate) enters the DLL
+        // -> 2 threads in 1 DLL -> Nexus hang -> writeIndex stall -> watchdog
+        // kills the bridge (observed: defer OK, attach after STOP still
+        // restarted). setReloading is a flag under the engine mutex; renderAll
+        // skips reloading channels, so no process() can race the job. The job
+        // keeps its own setReloading + restore logic unchanged. Dat o day (sau
+        // window create) de window fail khong keo mute vinh vien.
+        {
+            std::string gp0 = lower_plugin_path(guiCh);
+            if (!gp0.empty()) {
+                for (uint32_t y = 0; y < 16; ++y) {
+                    if (y == guiCh) continue;
+                    if (!instruments.get(y)) continue;
+                    if (lower_plugin_path(y) == gp0)
+                        instruments.setReloading(y, true);
+                }
+                instruments.setReloading(guiCh, true);
+            }
+        }
         workers[guiCh]->post([&instruments, guiCh, hwnd, arg2 = pluginId]() {
             if (!instruments.get(guiCh)) {
                 std::cerr << "[NativeBridge] GUI attach FAILED hwnd=" << hwnd
@@ -1424,7 +1459,8 @@ int main(int argc, char* argv[]) {
             {
                 std::lock_guard<std::mutex> lock(g_pendingGuiMutex);
                 for (auto it = g_pendingGui.begin(); it != g_pendingGui.end(); ) {
-                    if (instruments.get(it->first)) {
+                    // G0.1: giu entry khi dang PLAY - handleOpenGui se defer lai
+                    if (transportStopped && instruments.get(it->first)) {
                         readyGui.push_back({ it->first, it->second });
                         it = g_pendingGui.erase(it);
                     } else ++it;