2 files changed, 227 insertions, 153 deletions

diff --git a/src/input_common/main.cpp b/src/input_common/main.cpp
index 8e67a7437..57e7a25fe 100644
--- a/src/input_common/main.cpp
+++ b/src/input_common/main.cpp
@@ -18,66 +18,166 @@
 
 namespace InputCommon {
 
-static std::shared_ptr<Keyboard> keyboard;
-static std::shared_ptr<MotionEmu> motion_emu;
+struct InputSubsystem::Impl {
+    void Initialize() {
+        auto gcadapter = std::make_shared<GCAdapter::Adapter>();
+        gcbuttons = std::make_shared<GCButtonFactory>(gcadapter);
+        Input::RegisterFactory<Input::ButtonDevice>("gcpad", gcbuttons);
+        gcanalog = std::make_shared<GCAnalogFactory>(gcadapter);
+        Input::RegisterFactory<Input::AnalogDevice>("gcpad", gcanalog);
+
+        keyboard = std::make_shared<Keyboard>();
+        Input::RegisterFactory<Input::ButtonDevice>("keyboard", keyboard);
+        Input::RegisterFactory<Input::AnalogDevice>("analog_from_button",
+                                                    std::make_shared<AnalogFromButton>());
+        motion_emu = std::make_shared<MotionEmu>();
+        Input::RegisterFactory<Input::MotionDevice>("motion_emu", motion_emu);
+
 #ifdef HAVE_SDL2
-static std::unique_ptr<SDL::State> sdl;
+        sdl = SDL::Init();
 #endif
-static std::unique_ptr<CemuhookUDP::State> udp;
-static std::shared_ptr<GCButtonFactory> gcbuttons;
-static std::shared_ptr<GCAnalogFactory> gcanalog;
-
-void Init() {
-    auto gcadapter = std::make_shared<GCAdapter::Adapter>();
-    gcbuttons = std::make_shared<GCButtonFactory>(gcadapter);
-    Input::RegisterFactory<Input::ButtonDevice>("gcpad", gcbuttons);
-    gcanalog = std::make_shared<GCAnalogFactory>(gcadapter);
-    Input::RegisterFactory<Input::AnalogDevice>("gcpad", gcanalog);
-
-    keyboard = std::make_shared<Keyboard>();
-    Input::RegisterFactory<Input::ButtonDevice>("keyboard", keyboard);
-    Input::RegisterFactory<Input::AnalogDevice>("analog_from_button",
-                                                std::make_shared<AnalogFromButton>());
-    motion_emu = std::make_shared<MotionEmu>();
-    Input::RegisterFactory<Input::MotionDevice>("motion_emu", motion_emu);
 
+        udp = CemuhookUDP::Init();
+    }
+
+    void Shutdown() {
+        Input::UnregisterFactory<Input::ButtonDevice>("keyboard");
+        keyboard.reset();
+        Input::UnregisterFactory<Input::AnalogDevice>("analog_from_button");
+        Input::UnregisterFactory<Input::MotionDevice>("motion_emu");
+        motion_emu.reset();
 #ifdef HAVE_SDL2
-    sdl = SDL::Init();
+        sdl.reset();
 #endif
-    udp = CemuhookUDP::Init();
-}
+        udp.reset();
+        Input::UnregisterFactory<Input::ButtonDevice>("gcpad");
+        Input::UnregisterFactory<Input::AnalogDevice>("gcpad");
+
+        gcbuttons.reset();
+        gcanalog.reset();
+    }
+
+    [[nodiscard]] std::vector<Common::ParamPackage> GetInputDevices() const {
+        std::vector<Common::ParamPackage> devices = {
+            Common::ParamPackage{{"display", "Any"}, {"class", "any"}},
+            Common::ParamPackage{{"display", "Keyboard/Mouse"}, {"class", "key"}},
+        };
+#ifdef HAVE_SDL2
+        auto sdl_devices = sdl->GetInputDevices();
+        devices.insert(devices.end(), sdl_devices.begin(), sdl_devices.end());
+#endif
+        auto udp_devices = udp->GetInputDevices();
+        devices.insert(devices.end(), udp_devices.begin(), udp_devices.end());
+        return devices;
+    }
+
+    [[nodiscard]] AnalogMapping GetAnalogMappingForDevice(
+        const Common::ParamPackage& params) const {
+        if (!params.Has("class") || params.Get("class", "") == "any") {
+            return {};
+        }
+        if (params.Get("class", "") == "key") {
+            // TODO consider returning the SDL key codes for the default keybindings
+            return {};
+        }
+#ifdef HAVE_SDL2
+        if (params.Get("class", "") == "sdl") {
+            return sdl->GetAnalogMappingForDevice(params);
+        }
+#endif
+        return {};
+    }
+
+    [[nodiscard]] ButtonMapping GetButtonMappingForDevice(
+        const Common::ParamPackage& params) const {
+        if (!params.Has("class") || params.Get("class", "") == "any") {
+            return {};
+        }
+        if (params.Get("class", "") == "key") {
+            // TODO consider returning the SDL key codes for the default keybindings
+            return {};
+        }
+#ifdef HAVE_SDL2
+        if (params.Get("class", "") == "sdl") {
+            return sdl->GetButtonMappingForDevice(params);
+        }
+#endif
+        return {};
+    }
 
-void Shutdown() {
-    Input::UnregisterFactory<Input::ButtonDevice>("keyboard");
-    keyboard.reset();
-    Input::UnregisterFactory<Input::AnalogDevice>("analog_from_button");
-    Input::UnregisterFactory<Input::MotionDevice>("motion_emu");
-    motion_emu.reset();
+    std::shared_ptr<Keyboard> keyboard;
+    std::shared_ptr<MotionEmu> motion_emu;
 #ifdef HAVE_SDL2
-    sdl.reset();
+    std::unique_ptr<SDL::State> sdl;
 #endif
-    udp.reset();
-    Input::UnregisterFactory<Input::ButtonDevice>("gcpad");
-    Input::UnregisterFactory<Input::AnalogDevice>("gcpad");
+    std::unique_ptr<CemuhookUDP::State> udp;
+    std::shared_ptr<GCButtonFactory> gcbuttons;
+    std::shared_ptr<GCAnalogFactory> gcanalog;
+};
+
+InputSubsystem::InputSubsystem() : impl{std::make_unique<Impl>()} {}
+
+InputSubsystem::~InputSubsystem() = default;
+
+void InputSubsystem::Initialize() {
+    impl->Initialize();
+}
+
+void InputSubsystem::Shutdown() {
+    impl->Shutdown();
+}
+
+Keyboard* InputSubsystem::GetKeyboard() {
+    return impl->keyboard.get();
+}
+
+const Keyboard* InputSubsystem::GetKeyboard() const {
+    return impl->keyboard.get();
+}
+
+MotionEmu* InputSubsystem::GetMotionEmu() {
+    return impl->motion_emu.get();
+}
+
+const MotionEmu* InputSubsystem::GetMotionEmu() const {
+    return impl->motion_emu.get();
+}
+
+std::vector<Common::ParamPackage> InputSubsystem::GetInputDevices() const {
+    return impl->GetInputDevices();
+}
+
+AnalogMapping InputSubsystem::GetAnalogMappingForDevice(const Common::ParamPackage& device) const {
+    return impl->GetAnalogMappingForDevice(device);
+}
 
-    gcbuttons.reset();
-    gcanalog.reset();
+ButtonMapping InputSubsystem::GetButtonMappingForDevice(const Common::ParamPackage& device) const {
+    return impl->GetButtonMappingForDevice(device);
 }
 
-Keyboard* GetKeyboard() {
-    return keyboard.get();
+GCAnalogFactory* InputSubsystem::GetGCAnalogs() {
+    return impl->gcanalog.get();
 }
 
-MotionEmu* GetMotionEmu() {
-    return motion_emu.get();
+const GCAnalogFactory* InputSubsystem::GetGCAnalogs() const {
+    return impl->gcanalog.get();
 }
 
-GCButtonFactory* GetGCButtons() {
-    return gcbuttons.get();
+GCButtonFactory* InputSubsystem::GetGCButtons() {
+    return impl->gcbuttons.get();
 }
 
-GCAnalogFactory* GetGCAnalogs() {
-    return gcanalog.get();
+const GCButtonFactory* InputSubsystem::GetGCButtons() const {
+    return impl->gcbuttons.get();
+}
+
+std::vector<std::unique_ptr<Polling::DevicePoller>> InputSubsystem::GetPollers(
+    Polling::DeviceType type) const {
+#ifdef HAVE_SDL2
+    return impl->sdl->GetPollers(type);
+#else
+    return {};
+#endif
 }
 
 std::string GenerateKeyboardParam(int key_code) {
@@ -101,68 +201,4 @@ std::string GenerateAnalogParamFromKeys(int key_up, int key_down, int key_left,
     };
     return circle_pad_param.Serialize();
 }
-
-std::vector<Common::ParamPackage> GetInputDevices() {
-    std::vector<Common::ParamPackage> devices = {
-        Common::ParamPackage{{"display", "Any"}, {"class", "any"}},
-        Common::ParamPackage{{"display", "Keyboard/Mouse"}, {"class", "key"}},
-    };
-#ifdef HAVE_SDL2
-    auto sdl_devices = sdl->GetInputDevices();
-    devices.insert(devices.end(), sdl_devices.begin(), sdl_devices.end());
-#endif
-    auto udp_devices = udp->GetInputDevices();
-    devices.insert(devices.end(), udp_devices.begin(), udp_devices.end());
-    return devices;
-}
-
-std::unordered_map<Settings::NativeButton::Values, Common::ParamPackage> GetButtonMappingForDevice(
-    const Common::ParamPackage& params) {
-    std::unordered_map<Settings::NativeButton::Values, Common::ParamPackage> mappings;
-    if (!params.Has("class") || params.Get("class", "") == "any") {
-        return {};
-    }
-    if (params.Get("class", "") == "key") {
-        // TODO consider returning the SDL key codes for the default keybindings
-        return {};
-    }
-#ifdef HAVE_SDL2
-    if (params.Get("class", "") == "sdl") {
-        return sdl->GetButtonMappingForDevice(params);
-    }
-#endif
-    return {};
-}
-
-std::unordered_map<Settings::NativeAnalog::Values, Common::ParamPackage> GetAnalogMappingForDevice(
-    const Common::ParamPackage& params) {
-    std::unordered_map<Settings::NativeAnalog::Values, Common::ParamPackage> mappings;
-    if (!params.Has("class") || params.Get("class", "") == "any") {
-        return {};
-    }
-    if (params.Get("class", "") == "key") {
-        // TODO consider returning the SDL key codes for the default keybindings
-        return {};
-    }
-#ifdef HAVE_SDL2
-    if (params.Get("class", "") == "sdl") {
-        return sdl->GetAnalogMappingForDevice(params);
-    }
-#endif
-    return {};
-}
-
-namespace Polling {
-
-std::vector<std::unique_ptr<DevicePoller>> GetPollers(DeviceType type) {
-    std::vector<std::unique_ptr<DevicePoller>> pollers;
-
-#ifdef HAVE_SDL2
-    pollers = sdl->GetPollers(type);
-#endif
-
-    return pollers;
-}
-
-} // namespace Polling
 } // namespace InputCommon
diff --git a/src/input_common/main.h b/src/input_common/main.h
index e706c3750..f66308163 100644
--- a/src/input_common/main.h
+++ b/src/input_common/main.h
@@ -16,52 +16,6 @@ class ParamPackage;
 }
 
 namespace InputCommon {
-
-/// Initializes and registers all built-in input device factories.
-void Init();
-
-/// Deregisters all built-in input device factories and shuts them down.
-void Shutdown();
-
-class Keyboard;
-
-/// Gets the keyboard button device factory.
-Keyboard* GetKeyboard();
-
-class MotionEmu;
-
-/// Gets the motion emulation factory.
-MotionEmu* GetMotionEmu();
-
-GCButtonFactory* GetGCButtons();
-
-GCAnalogFactory* GetGCAnalogs();
-
-/// Generates a serialized param package for creating a keyboard button device
-std::string GenerateKeyboardParam(int key_code);
-
-/// Generates a serialized param package for creating an analog device taking input from keyboard
-std::string GenerateAnalogParamFromKeys(int key_up, int key_down, int key_left, int key_right,
-                                        int key_modifier, float modifier_scale);
-
-/**
- * Return a list of available input devices that this Factory can create a new device with.
- * Each returned Parampackage should have a `display` field used for display, a class field for
- * backends to determine if this backend is meant to service the request and any other information
- * needed to identify this in the backend later.
- */
-std::vector<Common::ParamPackage> GetInputDevices();
-
-/**
- * Given a ParamPackage for a Device returned from `GetInputDevices`, attempt to get the default
- * mapping for the device. This is currently only implemented for the sdl backend devices.
- */
-using ButtonMapping = std::unordered_map<Settings::NativeButton::Values, Common::ParamPackage>;
-using AnalogMapping = std::unordered_map<Settings::NativeAnalog::Values, Common::ParamPackage>;
-
-ButtonMapping GetButtonMappingForDevice(const Common::ParamPackage&);
-AnalogMapping GetAnalogMappingForDevice(const Common::ParamPackage&);
-
 namespace Polling {
 
 enum class DeviceType { Button, AnalogPreferred };
@@ -90,4 +44,88 @@ public:
 // Get all DevicePoller from all backends for a specific device type
 std::vector<std::unique_ptr<DevicePoller>> GetPollers(DeviceType type);
 } // namespace Polling
+
+class GCAnalogFactory;
+class GCButtonFactory;
+class Keyboard;
+class MotionEmu;
+
+/**
+ * Given a ParamPackage for a Device returned from `GetInputDevices`, attempt to get the default
+ * mapping for the device. This is currently only implemented for the SDL backend devices.
+ */
+using AnalogMapping = std::unordered_map<Settings::NativeAnalog::Values, Common::ParamPackage>;
+using ButtonMapping = std::unordered_map<Settings::NativeButton::Values, Common::ParamPackage>;
+
+class InputSubsystem {
+public:
+    explicit InputSubsystem();
+    ~InputSubsystem();
+
+    InputSubsystem(const InputSubsystem&) = delete;
+    InputSubsystem& operator=(const InputSubsystem&) = delete;
+
+    InputSubsystem(InputSubsystem&&) = delete;
+    InputSubsystem& operator=(InputSubsystem&&) = delete;
+
+    /// Initializes and registers all built-in input device factories.
+    void Initialize();
+
+    /// Unregisters all built-in input device factories and shuts them down.
+    void Shutdown();
+
+    /// Retrieves the underlying keyboard device.
+    [[nodiscard]] Keyboard* GetKeyboard();
+
+    /// Retrieves the underlying keyboard device.
+    [[nodiscard]] const Keyboard* GetKeyboard() const;
+
+    /// Retrieves the underlying motion emulation factory.
+    [[nodiscard]] MotionEmu* GetMotionEmu();
+
+    /// Retrieves the underlying motion emulation factory.
+    [[nodiscard]] const MotionEmu* GetMotionEmu() const;
+
+    /**
+     * Returns all available input devices that this Factory can create a new device with.
+     * Each returned ParamPackage should have a `display` field used for display, a class field for
+     * backends to determine if this backend is meant to service the request and any other
+     * information needed to identify this in the backend later.
+     */
+    [[nodiscard]] std::vector<Common::ParamPackage> GetInputDevices() const;
+
+    /// Retrieves the analog mappings for the given device.
+    [[nodiscard]] AnalogMapping GetAnalogMappingForDevice(const Common::ParamPackage& device) const;
+
+    /// Retrieves the button mappings for the given device.
+    [[nodiscard]] ButtonMapping GetButtonMappingForDevice(const Common::ParamPackage& device) const;
+
+    /// Retrieves the underlying GameCube analog handler.
+    [[nodiscard]] GCAnalogFactory* GetGCAnalogs();
+
+    /// Retrieves the underlying GameCube analog handler.
+    [[nodiscard]] const GCAnalogFactory* GetGCAnalogs() const;
+
+    /// Retrieves the underlying GameCube button handler.
+    [[nodiscard]] GCButtonFactory* GetGCButtons();
+
+    /// Retrieves the underlying GameCube button handler.
+    [[nodiscard]] const GCButtonFactory* GetGCButtons() const;
+
+    /// Get all DevicePoller from all backends for a specific device type
+    [[nodiscard]] std::vector<std::unique_ptr<Polling::DevicePoller>> GetPollers(
+        Polling::DeviceType type) const;
+
+private:
+    struct Impl;
+    std::unique_ptr<Impl> impl;
+};
+
+/// Generates a serialized param package for creating a keyboard button device
+std::string GenerateKeyboardParam(int key_code);
+
+/// Generates a serialized param package for creating an analog device taking input from keyboard
+std::string GenerateAnalogParamFromKeys(int key_up, int key_down, int key_left, int key_right,
+                                        int key_modifier, float modifier_scale);
+
 } // namespace InputCommon