1 files changed, 64 insertions, 0 deletions

diff --git a/src/hid_core/frontend/input_interpreter.cpp b/src/hid_core/frontend/input_interpreter.cpp
new file mode 100644
index 000000000..b6c8d8c5d
--- /dev/null
+++ b/src/hid_core/frontend/input_interpreter.cpp
@@ -0,0 +1,64 @@
+// SPDX-FileCopyrightText: Copyright 2020 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "core/core.h"
+#include "core/hle/service/hid/hid_server.h"
+#include "core/hle/service/sm/sm.h"
+#include "hid_core/frontend/input_interpreter.h"
+#include "hid_core/hid_types.h"
+#include "hid_core/resource_manager.h"
+#include "hid_core/resources/npad/npad.h"
+
+InputInterpreter::InputInterpreter(Core::System& system)
+    : npad{system.ServiceManager()
+               .GetService<Service::HID::IHidServer>("hid")
+               ->GetResourceManager()
+               ->GetNpad()} {
+    ResetButtonStates();
+}
+
+InputInterpreter::~InputInterpreter() = default;
+
+void InputInterpreter::PollInput() {
+    if (npad == nullptr) {
+        return;
+    }
+    const auto button_state = npad->GetAndResetPressState();
+
+    previous_index = current_index;
+    current_index = (current_index + 1) % button_states.size();
+
+    button_states[current_index] = button_state;
+}
+
+void InputInterpreter::ResetButtonStates() {
+    previous_index = 0;
+    current_index = 0;
+
+    button_states[0] = Core::HID::NpadButton::All;
+
+    for (std::size_t i = 1; i < button_states.size(); ++i) {
+        button_states[i] = Core::HID::NpadButton::None;
+    }
+}
+
+bool InputInterpreter::IsButtonPressed(Core::HID::NpadButton button) const {
+    return True(button_states[current_index] & button);
+}
+
+bool InputInterpreter::IsButtonPressedOnce(Core::HID::NpadButton button) const {
+    const bool current_press = True(button_states[current_index] & button);
+    const bool previous_press = True(button_states[previous_index] & button);
+
+    return current_press && !previous_press;
+}
+
+bool InputInterpreter::IsButtonHeld(Core::HID::NpadButton button) const {
+    Core::HID::NpadButton held_buttons{button_states[0]};
+
+    for (std::size_t i = 1; i < button_states.size(); ++i) {
+        held_buttons &= button_states[i];
+    }
+
+    return True(held_buttons & button);
+}