port some functionality to web

Author: Totto16

src/meson.build

@@ -52,6 +52,7 @@ src_files += files(
     'types.hpp',
     'utils.cpp',
     'utils.hpp',
+    'web_utils.cpp',
     'window.cpp',
     'window.hpp',
 )

src/tetris_application.cpp

@@ -2,6 +2,10 @@
 #include "utils.hpp"
 #include <tl/optional.hpp>
 
+#if defined(__EMSCRIPTEN__)
+#include "web_utils.hpp"
+#endif
+
 TetrisApplication::TetrisApplication(CommandLineArguments command_line_arguments)
 #if defined(__ANDROID__)
     : Application{ "OOPetris", WindowPosition::Centered, std::move(command_line_arguments) } {
@@ -135,13 +139,19 @@ void TetrisApplication::render() const {
     }
 }
 
-void TetrisApplication::try_load_settings() try {
-    std::ifstream settings_file{ settings_filename };
-    m_settings = nlohmann::json::parse(settings_file);
-    spdlog::info("settings loaded");
-} catch (...) {
-    spdlog::error("unable to load settings from \"{}\"", settings_filename);
-    spdlog::warn("applying default settings");
+void TetrisApplication::try_load_settings() {
+    try {
+#if defined(__EMSCRIPTEN__)
+        const std::string settings_string = utils::LocalStorage::get_item(settings_filename);
+        m_settings = nlohmann::json::parse(settings_string);
+#else
+        m_settings = nlohmann::json::parse(settings_file);
+#endif
+        spdlog::info("settings loaded");
+    } catch (...) {
+        spdlog::error("unable to load settings from \"{}\"", settings_filename);
+        spdlog::warn("applying default settings");
+    }
 }
 
 [[nodiscard]] bool TetrisApplication::is_replay_mode() const {

src/tetris_application.hpp

@@ -16,8 +16,11 @@ struct TetrisApplication : public Application {
 private:
     using TetrionHeaders = std::vector<Recording::TetrionHeader>;
 
+#if defined(__EMSCRIPTEN__)
+    static constexpr auto settings_filename = "settings_key";
+#else
     static constexpr auto settings_filename = "settings.json";
-
+#endif
     std::vector<std::unique_ptr<ClockSource>> m_clock_sources;
     std::vector<SimulationStep> m_simulation_step_indices;
     std::vector<std::unique_ptr<Tetrion>> m_tetrions;

src/web_utils.cpp

@@ -0,0 +1,44 @@
+
+#if defined(__EMSCRIPTEN__)
+#include "web_utils.hpp"
+#include <emscripten.h>
+#include <string>
+#include <tl/optional.hpp>
+
+tl::optional<std::string> utils::LocalStorage::get_item(const std::string& key) {
+
+
+    thread_local const emscripten::val localStorage = emscripten::val::global("localStorage");
+
+    emscripten::val value localStorage.getItem(key.c_str());
+
+    if (value.isUndefined()) {
+        return tl::nullopt;
+    }
+
+    return value.as<std::string | undefined>();
+}
+
+void utils::LocalStorage::set_item(const std::string& key, const std::string& value) {
+
+    thread_local const emscripten::val localStorage = emscripten::val::global("localStorage");
+
+    localStorage.setItem(key.c_str(), value.c_str());
+}
+
+void utils::LocalStorage::remove_item(const std::string& key) {
+
+    thread_local const emscripten::val localStorage = emscripten::val::global("localStorage");
+
+    localStorage.removeItem(key.c_str());
+}
+
+void utils::LocalStorage::clear() {
+
+    thread_local const emscripten::val localStorage = emscripten::val::global("localStorage");
+
+    localStorage.clear();
+}
+
+
+#endif

src/web_utils.hpp

@@ -0,0 +1,25 @@
+
+
+#pragma once
+
+#include <string>
+#include <tl/optional.hpp>
+
+
+#if not defined(__EMSCRIPTEN__)
+#error this header is for emscripten only
+#endif
+
+namespace utils {
+
+
+    struct LocalStorage {
+
+        static tl::optional<std::string> [[nodiscard]] get_item(const std::string& key);
+        static void set_item(const std::string& key, const std::string& value);
+        static void remove_item(const std::string& key);
+        static void clear();
+    };
+
+
+}; // namespace utils