Qt: Implement GBA host and widget

Source/Core/DolphinQt/GBAHost.cpp

@@ -0,0 +1,61 @@
+// Copyright 2021 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "DolphinQt/GBAHost.h"
+
+#include <QApplication>
+
+#include "Core/HW/GBACore.h"
+#include "DolphinQt/GBAWidget.h"
+#include "DolphinQt/QtUtils/QueueOnObject.h"
+
+GBAHost::GBAHost(std::weak_ptr<HW::GBA::Core> core)
+{
+  m_widget_controller = new GBAWidgetController();
+  m_widget_controller->moveToThread(qApp->thread());
+  m_core = std::move(core);
+  auto core_ptr = m_core.lock();
+
+  int device_number = core_ptr->GetDeviceNumber();
+  std::string game_title = core_ptr->GetGameTitle();
+  u32 width, height;
+  core_ptr->GetVideoDimensions(&width, &height);
+
+  QueueOnObject(m_widget_controller, [widget_controller = m_widget_controller, core = m_core,
+                                      device_number, game_title, width, height] {
+    widget_controller->Create(core, device_number, game_title, width, height);
+  });
+}
+
+GBAHost::~GBAHost()
+{
+  m_widget_controller->deleteLater();
+}
+
+void GBAHost::GameChanged()
+{
+  auto core_ptr = m_core.lock();
+  if (!core_ptr || !core_ptr->IsStarted())
+    return;
+
+  std::string game_title = core_ptr->GetGameTitle();
+  u32 width, height;
+  core_ptr->GetVideoDimensions(&width, &height);
+
+  QueueOnObject(m_widget_controller,
+                [widget_controller = m_widget_controller, game_title, width, height] {
+                  widget_controller->GameChanged(game_title, width, height);
+                });
+}
+
+void GBAHost::FrameEnded(const std::vector<u32>& video_buffer)
+{
+  QueueOnObject(m_widget_controller, [widget_controller = m_widget_controller, video_buffer] {
+    widget_controller->FrameEnded(video_buffer);
+  });
+}
+
+std::unique_ptr<GBAHostInterface> Host_CreateGBAHost(std::weak_ptr<HW::GBA::Core> core)
+{
+  return std::make_unique<GBAHost>(core);
+}