1 files changed, 82 insertions, 0 deletions
diff --git a/src/win/native/GodWindow.cpp b/src/win/native/GodWindow.cpp
new file mode 100644
index 00000000..076954d4
--- /dev/null
+++ b/src/win/native/GodWindow.cpp
@@ -0,0 +1,82 @@
+#include "cru/win/native/GodWindow.hpp"
+
+#include "cru/common/Logger.hpp"
+#include "cru/win/native/Exception.hpp"
+#include "cru/win/native/UiApplication.hpp"
+#include "cru/win/native/WindowClass.hpp"
+#include "GodWindowMessage.hpp"
+#include "Timer.hpp"
+
+namespace cru::platform::native::win {
+constexpr auto god_window_class_name = L"GodWindowClass";
+
+LRESULT CALLBACK GodWndProc(HWND hWnd, UINT uMsg, WPARAM wParam,
+                            LPARAM lParam) {
+  const auto app = WinUiApplication::GetInstance();
+
+  if (app) {
+    LRESULT result;
+    const auto handled = app->GetGodWindow()->HandleGodWindowMessage(
+        hWnd, uMsg, wParam, lParam, &result);
+    if (handled)
+      return result;
+    else
+      return DefWindowProcW(hWnd, uMsg, wParam, lParam);
+  } else
+    return DefWindowProcW(hWnd, uMsg, wParam, lParam);
+}
+
+GodWindow::GodWindow(WinUiApplication* application) {
+  application_ = application;
+
+  const auto h_instance = application->GetInstanceHandle();
+
+  god_window_class_ = std::make_unique<WindowClass>(god_window_class_name,
+                                                    GodWndProc, h_instance);
+
+  hwnd_ = CreateWindowEx(0, god_window_class_name, L"", 0, CW_USEDEFAULT,
+                         CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
+                         HWND_MESSAGE, nullptr, h_instance, nullptr);
+
+  if (hwnd_ == nullptr)
+    throw Win32Error(::GetLastError(), "Failed to create god window.");
+}
+
+GodWindow::~GodWindow() {
+  if (!::DestroyWindow(hwnd_)) {
+    // Although this could be "safely" ignore.
+    log::Warn("Failed to destroy god window.");
+  }
+}
+
+bool GodWindow::HandleGodWindowMessage(HWND hwnd, UINT msg, WPARAM w_param,
+                                       LPARAM l_param, LRESULT* result) {
+  CRU_UNUSED(hwnd)
+  CRU_UNUSED(l_param)
+
+  switch (msg) {
+    case invoke_later_message_id: {
+      const auto p_action = reinterpret_cast<std::function<void()>*>(w_param);
+      (*p_action)();
+      delete p_action;
+      *result = 0;
+      return true;
+    }
+    case WM_TIMER: {
+      const auto id = static_cast<UINT_PTR>(w_param);
+      const auto action = application_->GetTimerManager()->GetAction(id);
+      if (action.has_value()) {
+        (action.value().second)();
+        if (!action.value().first)
+          application_->GetTimerManager()->KillTimer(id);
+        result = 0;
+        return true;
+      }
+      break;
+    }
+    default:
+      return false;
+  }
+  return false;
+}
+}  // namespace cru::platform::native::win