[nostalgia/studio] Start on ImGui version of Studio

src/nostalgia/studio/lib/configio.hpp

@@ -0,0 +1,105 @@
+/*
+ * Copyright 2016 - 2021 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <filesystem>
+#include <fstream>
+
+#include <ox/model/typenamecatcher.hpp>
+#include <ox/oc/oc.hpp>
+#include <ox/std/buffer.hpp>
+#include <ox/std/defines.hpp>
+#include <ox/std/fmt.hpp>
+#include <ox/std/trace.hpp>
+#include <ox/std/string.hpp>
+
+namespace nostalgia::studio {
+
+constexpr auto ConfigDir = [] {
+	switch (ox::defines::OS) {
+		case ox::defines::OS::Darwin:
+			return "{}/Library/Preferences/NostalgiaStudio";
+		case ox::defines::OS::DragonFlyBSD:
+		case ox::defines::OS::FreeBSD:
+		case ox::defines::OS::Linux:
+		case ox::defines::OS::NetBSD:
+		case ox::defines::OS::OpenBSD:
+			return "{}/.config/NostalgiaStudio";
+		case ox::defines::OS::BareMetal:
+		case ox::defines::OS::Windows:
+			return "";
+	}
+}();
+
+template<typename T>
+ox::Result<T> readConfig(const ox::String &name = ox::getModelTypeName<T>()) noexcept {
+	const auto homeDir = std::getenv("HOME");
+	const auto configPath = ox::sfmt(ConfigDir, homeDir).toStdString();
+	const auto path = ox::sfmt("{}/{}.json", configPath, name).toStdString();
+	std::ifstream file(path, std::ios::binary | std::ios::ate);
+	if (!file.good()) {
+		oxErrorf("Could not find config file: {}", path);
+		return OxError(1, "Could not find config file");
+	}
+	try {
+		const auto size = file.tellg();
+		file.seekg(0, std::ios::beg);
+		ox::Buffer buff(static_cast<std::size_t>(size));
+		file.read(buff.data(), size);
+		return ox::readOC<T>(buff);
+	} catch (const std::ios_base::failure &e) {
+		oxErrorf("Could not read config file: {}", e.what());
+		return OxError(2, "Could not read config file");
+	}
+}
+
+template<typename T>
+ox::Error writeConfig(const ox::String &name, T *data) noexcept {
+	const auto homeDir = std::getenv("HOME");
+	const auto configPath = ox::sfmt(ConfigDir, homeDir).toStdString();
+	const auto path = ox::sfmt("{}/{}.json", configPath, name).toStdString();
+	std::error_code ec;
+	std::filesystem::create_directory(configPath, ec);
+	if (ec) {
+		oxErrf("Could not create config directory: {}\n", ec.message());
+	}
+	std::ofstream file(path, std::ios::binary | std::ios::ate);
+	if (!file.good()) {
+		oxErrorf("Could not find config file: {}", path);
+		return OxError(1, "Could not find config file");
+	}
+	oxRequireM(buff, ox::writeOC(data));
+	buff.back().value = '\n';
+	try {
+		file.write(buff.data(), static_cast<ox::Signed<decltype(buff.size())>>(buff.size()));
+		return OxError(0);
+	} catch (const std::ios_base::failure &e) {
+		oxErrorf("Could not read config file: {}", e.what());
+		return OxError(2, "Could not read config file");
+	}
+}
+
+template<typename T>
+ox::Error writeConfig(T *data) noexcept {
+	return writeConfig(ox::getModelTypeName<T>(), data);
+}
+
+template<typename T, typename Func>
+ox::Error editConfig(const ox::String &name, Func f) noexcept {
+	auto c = readConfig<T>(name);
+	f(&c.value);
+	return writeConfig(name, &c.value);
+}
+
+template<typename T, typename Func>
+ox::Error editConfig(Func f) noexcept {
+	return editConfig<T>(ox::getModelTypeName<T>(), f);
+}
+
+}