started work on config-system

added nlohmann_json library as submodule and to CMakeLists.txt
created basic config.json file in root folder
created ConfigLoader.h and added basic functionalities to it

.gitmodules

@@ -17,3 +17,6 @@
 	path = docs/doxygen-awesome-css
 	url = https://github.com/jothepro/doxygen-awesome-css.git
 
+[submodule "extern/nlohmann_json"]
+	path = extern/nlohmann_json
+	url = https://github.com/nlohmann/json.git

CMakeLists.txt

@@ -24,10 +24,13 @@ add_subdirectory(extern/SDL_image EXCLUDE_FROM_ALL)
 add_subdirectory(extern/SDL_mixer EXCLUDE_FROM_ALL)
 add_subdirectory(extern/SDL_ttf EXCLUDE_FROM_ALL)
 add_subdirectory(extern/tmxlite/tmxlite EXCLUDE_FROM_ALL)
+add_subdirectory(extern/nlohmann_json EXCLUDE_FROM_ALL)
 
 
 file(GLOB_RECURSE SOURCES ${ENGINE_SOURCE_DIR}/src/*.cpp)
-add_library(${PROJECT_NAME} ${SOURCES})
+add_library(${PROJECT_NAME} ${SOURCES}
+        include/ConfigLoader.h
+        src/ConfigLoader.cpp)
 
 target_include_directories(${PROJECT_NAME} PUBLIC ${ENGINE_INCLUDE_DIR})
 
@@ -37,6 +40,7 @@ target_link_libraries(${PROJECT_NAME} PUBLIC # should be private when all SDL fu
     SDL3_mixer::SDL3_mixer-static
     SDL3_ttf::SDL3_ttf-static
     tmxlite
+    nlohmann_json::nlohmann_json
 )
 
 if(CMAKE_BUILD_TYPE MATCHES "Debug")

config.json

@@ -0,0 +1,3 @@
+{
+  "fullscreen": false
+}

extern/nlohmann_json

@@ -0,0 +1 @@
+Subproject commit a006a7a48bb30a247f0344b788c62c2806edd90b

include/ConfigLoader.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include <nlohmann/json.hpp>
+
+using json = nlohmann::json;
+
+class ConfigLoader {
+
+public:
+    ConfigLoader();
+    ~ConfigLoader();
+
+    void init();
+
+    void setCustomConfig(std::string path);
+
+private:
+    json baseConfig;
+    std::optional<json> customConfig;
+    json finalConfig;
+
+    json loadConfigFromJSON(const std::string& path);
+    json mergeConfigs(json baseConfig, json customConfig); //<! Merges 2 config.json files, prioritising the custom to the base one
+};

src/ConfigLoader.cpp

@@ -0,0 +1,41 @@
+#include "ConfigLoader.h"
+
+#include <fstream>
+
+ConfigLoader::ConfigLoader() {
+    baseConfig = loadConfigFromJSON("config.json");
+}
+
+void ConfigLoader::init() {
+    if (!customConfig.has_value()) {
+        finalConfig = baseConfig;
+        return;
+    }
+    finalConfig = mergeConfigs(baseConfig, customConfig.value());
+}
+
+json ConfigLoader::loadConfigFromJSON(const std::string& path) {
+    std::ifstream config_file(path);
+    json config;
+
+    if (!config_file.is_open()) {
+        throw std::runtime_error(std::string("Could not load config file at: " + path));
+    }
+
+    config_file >> config;
+    return config;
+}
+
+
+void ConfigLoader::setCustomConfig(std::string path) {
+    customConfig.emplace(loadConfigFromJSON(path));
+}
+
+json ConfigLoader::mergeConfigs(json baseConfig, json customConfig) {
+    for (auto& entry : customConfig.items()) {
+        baseConfig[entry.key()] = entry.value();
+    }
+    return baseConfig;
+}
+
+