Qt: Allow rebinding keyboard controls (#779)

* Initial input UI draft

Co-Authored-By: Paris Oplopoios <parisoplop@gmail.com>

* More keybinding work

Co-Authored-By: Paris Oplopoios <parisoplop@gmail.com>

* Nit

Co-Authored-By: Paris Oplopoios <parisoplop@gmail.com>

* More nits

Co-Authored-By: Paris Oplopoios <parisoplop@gmail.com>

---------

Co-authored-by: Paris Oplopoios <parisoplop@gmail.com>

include/input_mappings.hpp

@@ -1,5 +1,10 @@
 #pragma once
 
+#include <filesystem>
+#include <fstream>
+#include <map>
+#include <optional>
+#include <toml.hpp>
 #include <unordered_map>
 
 #include "helpers.hpp"
@@ -15,8 +20,108 @@ struct InputMappings {
 	}
 
 	void setMapping(Scancode scancode, u32 key) { container[scancode] = key; }
+
+	template <typename ScancodeToString>
+	void serialize(const std::filesystem::path& path, const std::string& frontend, ScancodeToString scancodeToString) const {
+		toml::basic_value<toml::preserve_comments, std::map> data;
+
+		std::error_code error;
+		if (std::filesystem::exists(path, error)) {
+			try {
+				data = toml::parse<toml::preserve_comments, std::map>(path);
+			} catch (const std::exception& ex) {
+				Helpers::warn("Exception trying to parse mappings file. Exception: %s\n", ex.what());
+				return;
+			}
+		} else {
+			if (error) {
+				Helpers::warn("Filesystem error accessing %s (error: %s)\n", path.string().c_str(), error.message().c_str());
+			}
+			printf("Saving new mappings file %s\n", path.string().c_str());
+		}
+
+		data["Metadata"]["Name"] = name.empty() ? "Unnamed Mappings" : name;
+		data["Metadata"]["Device"] = device.empty() ? "Unknown Device" : device;
+		data["Metadata"]["Frontend"] = frontend;
+
+		data["Mappings"] = toml::table{};
+
+		for (const auto& [scancode, key] : container) {
+			const std::string& keyName = HID::Keys::keyToName(key);
+			if (!data["Mappings"].contains(keyName)) {
+				data["Mappings"][keyName] = toml::array{};
+			}
+			data["Mappings"][keyName].push_back(scancodeToString(scancode));
+		}
+
+		std::ofstream file(path, std::ios::out);
+		file << data;
+	}
+
+	template <typename ScancodeFromString>
+	static std::optional<InputMappings> deserialize(
+		const std::filesystem::path& path, const std::string& wantFrontend, ScancodeFromString stringToScancode
+	) {
+		toml::basic_value<toml::preserve_comments, std::map> data;
+		std::error_code error;
+
+		if (!std::filesystem::exists(path, error)) {
+			if (error) {
+				Helpers::warn("Filesystem error accessing %s (error: %s)\n", path.string().c_str(), error.message().c_str());
+			}
+
+			return std::nullopt;
+		}
+
+		InputMappings mappings;
+
+		try {
+			data = toml::parse<toml::preserve_comments, std::map>(path);
+
+			const auto metadata = toml::find(data, "Metadata");
+			mappings.name = toml::find_or<std::string>(metadata, "Name", "Unnamed Mappings");
+			mappings.device = toml::find_or<std::string>(metadata, "Device", "Unknown Device");
+
+			std::string haveFrontend = toml::find_or<std::string>(metadata, "Frontend", "Unknown Frontend");
+
+			bool equal = std::equal(haveFrontend.begin(), haveFrontend.end(), wantFrontend.begin(), wantFrontend.end(), [](char a, char b) {
+				return std::tolower(a) == std::tolower(b);
+			});
+
+			if (!equal) {
+				Helpers::warn(
+					"Mappings file %s was created for frontend %s, but we are using frontend %s\n", path.string().c_str(), haveFrontend.c_str(),
+					wantFrontend.c_str()
+				);
+
+				return std::nullopt;
+			}
+		} catch (const std::exception& ex) {
+			Helpers::warn("Exception trying to parse config file. Exception: %s\n", ex.what());
+			return std::nullopt;
+		}
+
+		const auto& mappingsTable = toml::find_or<toml::table>(data, "Mappings", toml::table{});
+		for (const auto& [keyName, scancodes] : mappingsTable) {
+			for (const auto& scancodeVal : scancodes.as_array()) {
+				std::string scancodeStr = scancodeVal.as_string();
+				mappings.setMapping(stringToScancode(scancodeStr), HID::Keys::nameToKey(keyName));
+			}
+		}
+
+		return mappings;
+	}
+
 	static InputMappings defaultKeyboardMappings();
 
+	auto begin() { return container.begin(); }
+	auto end() { return container.end(); }
+
+	auto begin() const { return container.begin(); }
+	auto end() const { return container.end(); }
+
   private:
 	Container container;
+	std::string name;
+	std::string device;
 };

include/panda_qt/config_window.hpp

@@ -16,6 +16,8 @@
 
 #include "emulator.hpp"
 #include "frontend_settings.hpp"
+#include "input_mappings.hpp"
+#include "panda_qt/input_window.hpp"
 
 class ConfigWindow : public QDialog {
 	Q_OBJECT
@@ -30,8 +32,9 @@ class ConfigWindow : public QDialog {
 	QTextEdit* helpText = nullptr;
 	QListWidget* widgetList = nullptr;
 	QStackedWidget* widgetContainer = nullptr;
+	InputWindow* inputWindow = nullptr;
 
-	static constexpr size_t settingWidgetCount = 6;
+	static constexpr size_t settingWidgetCount = 7;
 	std::array<QString, settingWidgetCount> helpTexts;
 
 	// The config class holds a copy of the emulator config which it edits and sends
@@ -52,6 +55,7 @@ class ConfigWindow : public QDialog {
 	~ConfigWindow();
 
 	EmulatorConfig& getConfig() { return config; }
+	InputWindow* getInputWindow() { return inputWindow; }
 
   private:
 	Emulator* emu;

include/panda_qt/input_window.hpp

@@ -0,0 +1,32 @@
+#pragma once
+
+#include <QDialog>
+#include <QKeySequence>
+#include <QMap>
+#include <QPushButton>
+
+#include "input_mappings.hpp"
+
+class InputWindow : public QDialog {
+	Q_OBJECT
+
+  public:
+	InputWindow(QWidget* parent = nullptr);
+
+	void loadFromMappings(const InputMappings& mappings);
+	void applyToMappings(InputMappings& mappings) const;
+
+  signals:
+	void mappingsChanged();
+
+  protected:
+	bool eventFilter(QObject* obj, QEvent* event) override;
+
+  private:
+	QMap<QString, QPushButton*> buttonMap;
+	QMap<QString, QKeySequence> keyMappings;
+
+	QString waitingForAction;
+
+	void startKeyCapture(const QString& action);
+};

include/panda_qt/main_window.hpp

@@ -43,7 +43,6 @@ class MainWindow : public QMainWindow {
 		Pause,
 		Resume,
 		TogglePause,
-		DumpRomFS,
 		PressKey,
 		ReleaseKey,
 		SetCirclePadX,
@@ -134,6 +133,9 @@ class MainWindow : public QMainWindow {
 	void dispatchMessage(const EmulatorMessage& message);
 	void loadTranslation();
 
+	void loadKeybindings();
+	void saveKeybindings();
+
 	// Tracks whether we are using an OpenGL-backed renderer or a Vulkan-backed renderer
 	bool usingGL = false;
 	bool usingVk = false;
@@ -145,6 +147,9 @@ class MainWindow : public QMainWindow {
 	bool keyboardAnalogX = false;
 	bool keyboardAnalogY = false;
 
+	// Tracks if keybindings changed, in which case we should update the keybindings file when closing the emulator
+	bool keybindingsChanged = false;
+
   public:
 	MainWindow(QApplication* app, QWidget* parent = nullptr);
 	~MainWindow();

include/services/hid.hpp

@@ -1,6 +1,7 @@
 #pragma once
 #include <array>
 #include <optional>
+#include <string>
 
 #include "helpers.hpp"
 #include "kernel_types.hpp"
@@ -38,7 +39,10 @@ namespace HID::Keys {
 		CirclePadUp = 1 << 30,     // Y >= 41
 		CirclePadDown = 1u << 31   // Y <= -41
 	};
-}
+
+	const char* keyToName(u32 key);
+	u32 nameToKey(std::string name);
+}  // namespace HID::Keys
 
 // Circular dependency because we need HID to spawn events
 class Kernel;