feat: use LocalStorage for settings instead of a file

Author: Totto16

src/manager/settings_manager.cpp

@@ -3,23 +3,64 @@
 #include "input/keyboard_input.hpp"
 #include "input/touch_input.hpp"
 
+#if defined(__EMSCRIPTEN__)
+#include "helper/web_utils.hpp"
+#endif
+
 namespace {
+#if defined(__EMSCRIPTEN__)
+    constexpr const auto settings_key = "settings_key";
+#else
     constexpr const auto settings_filename = "settings.json";
+#endif
 
-}
+} // namespace
 
 
 SettingsManager::SettingsManager() {
+
+#if defined(__EMSCRIPTEN__)
+    const auto content = web::LocalStorage::get_item(settings_key);
+
+    helper::expected<settings::Settings, std::pair<std::string, json::ParseError>> result =
+            helper::unexpected<std::pair<std::string, json::ParseError>>{ std::make_pair<std::string, json::ParseError>(
+                    "Key not present in LocalStorage", json::ParseError::OpenError
+            ) };
+
+    if (content.has_value()) {
+        auto parse_result = json::try_parse_json<settings::Settings>(content.value());
+
+        if (not parse_result.has_value()) {
+            result = helper::unexpected<std::pair<std::string, json::ParseError>>{
+                std::make_pair<std::string, json::ParseError>(
+                        std::move(parse_result.error()), json::ParseError::FormatError
+                )
+            };
+        } else {
+            result = parse_result.value();
+        }
+    }
+
+#else
     const std::filesystem::path settings_file = utils::get_root_folder() / settings_filename;
 
     const auto result = json::try_parse_json_file<settings::Settings>(settings_file);
+#endif
 
     if (result.has_value()) {
         m_settings = result.value();
     } else {
         auto [error, error_type] = result.error();
 
-        spdlog::error("unable to load settings from \"{}\": {}", settings_filename, error);
+        spdlog::error(
+                "unable to load settings from \"{}\": {}",
+#if defined(__EMSCRIPTEN__)
+                settings_key,
+#else
+                settings_filename,
+#endif
+                error
+        );
         spdlog::warn("applying default settings");
 
         m_settings = {
@@ -48,14 +89,32 @@ void SettingsManager::add_callback(Callback&& callback) {
 }
 
 void SettingsManager::save() const {
+
+#if defined(__EMSCRIPTEN__)
+    const auto maybe_settings_json = json::try_json_to_string<settings::Settings>(m_settings);
+
+    if (not maybe_settings_json.has_value()) {
+        spdlog::error(
+                "unable to save settings to LocalStorage\"{}\": unable to convert settings to json: {}", settings_key,
+                maybe_settings_json.error()
+        );
+        return;
+    }
+
+    web::LocalStorage::set_item(settings_key, maybe_settings_json.value());
+
+#else
     const std::filesystem::path settings_file = utils::get_root_folder() / settings_filename;
 
-    const auto result = json::try_write_json_to_file(settings_file, m_settings, true);
+    const auto result = json::try_write_json_to_file<settings::Settings>(settings_file, m_settings, true);
+
 
     if (result.has_value()) {
         spdlog::error("unable to save settings to \"{}\": {}", settings_filename, result.value());
         return;
     }
+#endif
+
 
     this->fire_callbacks();
 }