Add initial work on Qt frontend

src/duckstation-qt/settingsdialog.h

@@ -0,0 +1,44 @@
+#pragma once
+
+#include <QtWidgets/QDialog>
+#include "ui_settingsdialog.h"
+
+class QtHostInterface;
+
+class ConsoleSettingsWidget;
+
+class SettingsDialog : public QDialog
+{
+  Q_OBJECT
+
+public:
+  enum class Category
+  {
+    ConsoleSettings,
+    GameListSettings,
+    CPUSettings,
+    GPUSettings,
+    AudioSettings,
+    Count
+  };
+
+  explicit SettingsDialog(QtHostInterface* host_interface, QWidget* parent = nullptr);
+  ~SettingsDialog();
+
+public Q_SLOTS:
+  void setCategory(Category category);
+
+private Q_SLOTS:
+  void onCategoryCurrentRowChanged(int row);
+
+private:
+  Ui::SettingsDialog m_ui;
+
+  QtHostInterface* m_host_interface;
+
+  ConsoleSettingsWidget* m_console_settings = nullptr;
+  QWidget* m_game_list_settings = nullptr;
+  QWidget* m_cpu_settings = nullptr;
+  QWidget* m_gpu_settings = nullptr;
+  QWidget* m_audio_settings = nullptr;
+};