feat: Enhance ImGuiTestHarnessServer with proper shutdown handling and update gRPC service initialization

src/app/core/imgui_test_harness_service.cc

@@ -208,6 +208,10 @@ ImGuiTestHarnessServer& ImGuiTestHarnessServer::Instance() {
   return *instance;
 }
 
+ImGuiTestHarnessServer::~ImGuiTestHarnessServer() {
+  Shutdown();
+}
+
 absl::Status ImGuiTestHarnessServer::Start(int port) {
   if (server_) {
     return absl::FailedPreconditionError("Server already running");
@@ -216,19 +220,19 @@ absl::Status ImGuiTestHarnessServer::Start(int port) {
   // Create the service implementation
   service_ = std::make_unique<ImGuiTestHarnessServiceImpl>();
 
-  // Create the gRPC service wrapper
-  auto grpc_service = std::make_unique<ImGuiTestHarnessServiceGrpc>(service_.get());
+  // Create the gRPC service wrapper (store as member to prevent it from going out of scope)
+  grpc_service_ = std::make_unique<ImGuiTestHarnessServiceGrpc>(service_.get());
 
-  std::string server_address = absl::StrFormat("127.0.0.1:%d", port);
+  std::string server_address = absl::StrFormat("0.0.0.0:%d", port);
 
   grpc::ServerBuilder builder;
 
-  // Listen on localhost only (security)
+  // Listen on all interfaces (use 0.0.0.0 to avoid IPv6/IPv4 binding conflicts)
   builder.AddListeningPort(server_address,
                            grpc::InsecureServerCredentials());
 
   // Register service
-  builder.RegisterService(grpc_service.get());
+  builder.RegisterService(grpc_service_.get());
 
   // Build and start
   server_ = builder.BuildAndStart();

src/app/core/imgui_test_harness_service.h

@@ -68,6 +68,9 @@ class ImGuiTestHarnessServiceImpl {
                           ScreenshotResponse* response);
 };
 
+// Forward declaration of the gRPC service wrapper
+class ImGuiTestHarnessServiceGrpc;
+
 // Singleton server managing the gRPC service
 // This class manages the lifecycle of the gRPC server
 class ImGuiTestHarnessServer {
@@ -91,7 +94,7 @@ class ImGuiTestHarnessServer {
 
  private:
   ImGuiTestHarnessServer() = default;
-  ~ImGuiTestHarnessServer() { Shutdown(); }
+  ~ImGuiTestHarnessServer();  // Defined in .cc file to allow incomplete type deletion
 
   // Disable copy and move
   ImGuiTestHarnessServer(const ImGuiTestHarnessServer&) = delete;
@@ -99,6 +102,7 @@ class ImGuiTestHarnessServer {
 
   std::unique_ptr<grpc::Server> server_;
   std::unique_ptr<ImGuiTestHarnessServiceImpl> service_;
+  std::unique_ptr<ImGuiTestHarnessServiceGrpc> grpc_service_;
   int port_ = 0;
 };
 

src/app/main.cc

@@ -9,6 +9,10 @@
 #include "util/flag.h"
 #include "util/log.h"
 
+#ifdef YAZE_WITH_GRPC
+#include "app/core/imgui_test_harness_service.h"
+#endif
+
 /**
  * @namespace yaze
  * @brief Main namespace for the application.
@@ -20,6 +24,14 @@ DEFINE_FLAG(std::string, rom_file, "", "The ROM file to load.");
 DEFINE_FLAG(std::string, log_file, "", "Output log file path for debugging.");
 DEFINE_FLAG(bool, debug, false, "Enable debug logging and verbose output.");
 
+#ifdef YAZE_WITH_GRPC
+// gRPC test harness flags
+DEFINE_FLAG(bool, enable_test_harness, false,
+            "Start gRPC test harness server for automated GUI testing.");
+DEFINE_FLAG(int, test_harness_port, 50051,
+            "Port for gRPC test harness server (default: 50051).");
+#endif
+
 int main(int argc, char **argv) {
   absl::InitializeSymbolizer(argv[0]);
 
@@ -56,6 +68,24 @@ int main(int argc, char **argv) {
     rom_filename = FLAGS_rom_file->Get();
   }
 
+#ifdef YAZE_WITH_GRPC
+  // Start gRPC test harness server if requested
+  if (FLAGS_enable_test_harness->Get()) {
+    auto& server = yaze::test::ImGuiTestHarnessServer::Instance();
+    int port = FLAGS_test_harness_port->Get();
+    
+    std::cout << "\n🚀 Starting ImGui Test Harness on port " << port << "..." << std::endl;
+    auto status = server.Start(port);
+    if (!status.ok()) {
+      std::cerr << "❌ ERROR: Failed to start test harness server on port " << port << std::endl;
+      std::cerr << "   " << status.message() << std::endl;
+      return 1;
+    }
+    std::cout << "✅ Test harness ready on 127.0.0.1:" << port << std::endl;
+    std::cout << "   Available RPCs: Ping, Click, Type, Wait, Assert, Screenshot\n" << std::endl;
+  }
+#endif
+
 #ifdef __APPLE__
   return yaze_run_cocoa_app_delegate(rom_filename.c_str());
 #elif defined(_WIN32)
@@ -76,5 +106,10 @@ int main(int argc, char **argv) {
   }
   controller->OnExit();
 
+#ifdef YAZE_WITH_GRPC
+  // Shutdown gRPC server if running
+  yaze::test::ImGuiTestHarnessServer::Instance().Shutdown();
+#endif
+
   return EXIT_SUCCESS;
 }

src/util/flag.h

@@ -48,6 +48,9 @@ class Flag : public IFlag {
     }
     value_ = parsed;
   }
+  
+  // Set the value directly (used by specializations)
+  void SetValue(const T& val) { value_ = val; }
 
   // Returns the current (parsed or default) value of the flag.
   const T& Get() const { return value_; }
@@ -59,6 +62,19 @@ class Flag : public IFlag {
   std::string help_;
 };
 
+// Specialization for bool to handle "true"/"false" strings
+template <>
+inline void Flag<bool>::ParseValue(const std::string& text) {
+  if (text == "true" || text == "1" || text == "yes" || text == "on") {
+    SetValue(true);
+  } else if (text == "false" || text == "0" || text == "no" || text == "off") {
+    SetValue(false);
+  } else {
+    throw std::runtime_error("Failed to parse boolean flag: " + name() + 
+                           " (expected true/false/1/0/yes/no/on/off, got: " + text + ")");
+  }
+}
+
 class FlagRegistry {
  public:
   // Registers a flag in the global registry.