refactor(json): migrate from nlohmann to rapidjson

Replace nlohmann::json with rapidjson across localization, hitbox manager, server world, and sensitive filter. Add json_utils helper for converting rapidjson documents to maps, and improve parse error handling.

include/Cubed/tools/json_utils.hpp

@@ -0,0 +1,8 @@
+
+#include <rapidjson/document.h>
+#include <string>
+#include <unordered_map>
+namespace Tools {
+std::unordered_map<std::string, std::string>
+doc_to_map(const rapidjson::Document& doc);
+}

include/Cubed/tools/sensitive_filter.hpp

@@ -1,11 +1,13 @@
 #pragma once
 
-#include <nlohmann/json.hpp>
+#include <rapidjson/document.h>
+#include <unordered_map>
+#include <vector>
 namespace Cubed {
 class SensitiveFilter {
 public:
     SensitiveFilter();
-    void load(const nlohmann::json& j);
+    void load(const rapidjson::Document& doc);
     std::string filter(std::string_view text);
 
 private:

src/CMakeLists.txt

@@ -103,4 +103,5 @@ target_sources(${PROJECT_NAME}
         gameplay/server_entity_manager.cpp
         gameplay/client_entity_manager.cpp
         gameplay/systems/wander_ai_system.cpp
+        tools/json_utils.cpp
 )

src/gameplay/hitbox_manager.cpp

@@ -5,9 +5,10 @@
 #include "Cubed/tools/log.hpp"
 #include "Cubed/tools/name_space.hpp"
 
-#include <nlohmann/json.hpp>
+#include <rapidjson/document.h>
+#include <rapidjson/istreamwrapper.h>
 namespace fs = std::filesystem;
-using nlohmann::json;
+using namespace rapidjson;
 namespace Cubed {
 HitboxManager::HitboxManager() {
 
@@ -84,21 +85,30 @@ HitboxManager::Handle HitboxManager::load(std::string_view name) {
         glm::vec3 center;
         glm::vec3 half;
         std::ifstream s{p};
-        json j = json::parse(s);
-        if (j.contains("boxes")) {
-            const json* box = &j["boxes"];
-            if (box->is_array() && !box->empty()) {
-                box = &(*box)[0];
-            }
-            if (box->contains("center")) {
-                center.x = (*box)["center"].at(0).get<float>();
-                center.y = (*box)["center"].at(1).get<float>();
-                center.z = (*box)["center"].at(2).get<float>();
-            }
-            if (box->contains("half")) {
-                half.x = (*box)["half"].at(0).get<float>();
-                half.y = (*box)["half"].at(1).get<float>();
-                half.z = (*box)["half"].at(2).get<float>();
+        IStreamWrapper isw(s);
+        Document doc;
+        doc.ParseStream(isw);
+        if (doc.HasParseError()) {
+            auto code = doc.GetParseError();
+
+            throw std::runtime_error(
+                std::format("Parse {} failed, error code {}", p.string(),
+                            static_cast<int>(code)));
+        }
+        if (doc.HasMember("boxes")) {
+            const Value& box = doc["boxes"];
+            if (box.IsArray()) {
+                const Value& b = box[0];
+                if (b.HasMember("center")) {
+                    center.x = b["center"][0].GetFloat();
+                    center.y = b["center"][1].GetFloat();
+                    center.z = b["center"][2].GetFloat();
+                }
+                if (b.HasMember("half")) {
+                    half.x = b["half"][0].GetFloat();
+                    half.y = b["half"][1].GetFloat();
+                    half.z = b["half"][2].GetFloat();
+                }
             }
         }
         {

src/gameplay/server_world.cpp

@@ -8,14 +8,15 @@
 #include "Cubed/tools/net_utils.hpp"
 #include "Cubed/tools/uuid.hpp"
 
-#include <nlohmann/json.hpp>
 #include <ranges>
+#include <rapidjson/document.h>
+#include <rapidjson/istreamwrapper.h>
 #include <utility>
 using namespace std::chrono;
 using namespace std::chrono_literals;
 using namespace google::protobuf;
+using namespace rapidjson;
 namespace fs = std::filesystem;
-using nlohmann::json;
 namespace Cubed {
 ServerWorld::ServerWorld(Config& config)
     : m_config(config), m_entity_manager(*this) {}
@@ -212,8 +213,13 @@ void ServerWorld::init_world() {
     try {
         fs::path path = std::format("{}SensitiveLexicon.json", ASSETS_PATH);
         std::ifstream s{path};
-        json j = json::parse(s);
-        m_filter.load(j);
+        if (!s.is_open()) {
+            throw std::runtime_error("can't open SensitiveLexicon.json");
+        }
+        IStreamWrapper isw(s);
+        Document doc;
+        doc.ParseStream(isw);
+        m_filter.load(doc);
     } catch (const std::exception& e) {
         Logger::error("Load SensitiveLexicon.json Fail");
         m_enable_filter = false;

src/localization.cpp

@@ -1,12 +1,14 @@
 #include "Cubed/localization.hpp"
 
 #include "Cubed/tools/cubed_assert.hpp"
+#include "Cubed/tools/json_utils.hpp"
 #include "Cubed/tools/log.hpp"
 
 #include <fstream>
-#include <nlohmann/json.hpp>
-using json = nlohmann::json;
+#include <rapidjson/document.h>
+#include <rapidjson/istreamwrapper.h>
 namespace fs = std::filesystem;
+using namespace rapidjson;
 namespace Cubed {
 Localization::Localization() {}
 Localization& Localization::instance() {
@@ -25,10 +27,19 @@ void Localization::load_language(std::string_view language) {
         return;
     }
     try {
-        json j = json::parse(file);
+        IStreamWrapper isw(file);
+        Document doc;
+        doc.ParseStream(isw);
+        if (doc.HasParseError()) {
+            auto code = doc.GetParseError();
+
+            throw std::runtime_error(
+                std::format("Parse {} failed, error code {}", path,
+                            static_cast<int>(code)));
+        }
         m_translations.clear();
-        j.get_to(m_translations);
-    } catch (const json::parse_error& e) {
+        m_translations = Tools::doc_to_map(doc);
+    } catch (const std::exception& e) {
         Logger::error("JSON syntax error: {}", e.what());
     }
 }

src/tools/json_utils.cpp

@@ -0,0 +1,54 @@
+#include "Cubed/tools/json_utils.hpp"
+
+#include <rapidjson/document.h>
+#include <rapidjson/stringbuffer.h>
+#include <rapidjson/writer.h>
+#include <string>
+#include <unordered_map>
+namespace Tools {
+
+using rapidjson::Document;
+using rapidjson::Value;
+
+namespace {
+std::string serialize_value(const Value& v, rapidjson::StringBuffer& buf) {
+    rapidjson::Writer<rapidjson::StringBuffer> w(buf);
+    v.Accept(w);
+    return buf.GetString();
+}
+} // namespace
+
+std::unordered_map<std::string, std::string> doc_to_map(const Document& doc) {
+    std::unordered_map<std::string, std::string> m;
+    if (!doc.IsObject())
+        return m;
+
+    for (auto it = doc.MemberBegin(); it != doc.MemberEnd(); ++it) {
+        const std::string KEY(it->name.GetString(), it->name.GetStringLength());
+        const Value& v = it->value;
+        std::string val;
+        if (v.IsString()) {
+            val.assign(v.GetString(), v.GetStringLength());
+        } else if (v.IsInt()) {
+            val = std::to_string(v.GetInt());
+        } else if (v.IsUint()) {
+            val = std::to_string(v.GetUint());
+        } else if (v.IsInt64()) {
+            val = std::to_string(v.GetInt64());
+        } else if (v.IsUint64()) {
+            val = std::to_string(v.GetUint64());
+        } else if (v.IsDouble()) {
+            val = std::to_string(v.GetDouble());
+        } else if (v.IsBool()) {
+            val = v.GetBool() ? "true" : "false";
+        } else if (v.IsNull()) {
+            val = "null";
+        } else {
+            rapidjson::StringBuffer buf;
+            val = serialize_value(v, buf);
+        }
+        m.emplace(KEY, val);
+    }
+    return m;
+}
+} // namespace Tools

src/tools/sensitive_filter.cpp

@@ -2,18 +2,25 @@
 
 #include <queue>
 #include <utf8cpp/utf8.h>
-using nlohmann::json;
+using namespace rapidjson;
 namespace Cubed {
 SensitiveFilter::SensitiveFilter() {
 
 };
 
-void SensitiveFilter::load(const nlohmann::json& j) {
+void SensitiveFilter::load(const Document& doc) {
     trie.clear();
     trie.emplace_back();
-    for (const auto& item : j["words"]) {
-
-        auto str = item.get<std::string>();
+    if (!doc.HasMember("words")) {
+        return;
+    }
+    const Value& words = doc["words"];
+    for (SizeType i = 0; i < words.Size(); ++i) {
+        const auto& w = words[i];
+        if (!w.IsString()) {
+            continue;
+        }
+        std::string str(w.GetString(), w.GetStringLength());
         std::u32string word;
         utf8::utf8to32(str.begin(), str.end(), std::back_inserter(word));
         insert(word);