From fdc8dbed99cf34b3da0c909e40d1c6e164cddd50 Mon Sep 17 00:00:00 2001
From: nekosu <liao.hy@outlook.com>
Date: Wed, 24 Jan 2024 16:56:38 +0800
Subject: [PATCH] feat: yet another dump impl

---
 include/json.hpp  | 56 +++++++++++++++++++++++++++++++++++++++++++++++
 sample/sample.cpp | 33 ++++++++++++++++++++--------
 2 files changed, 80 insertions(+), 9 deletions(-)

diff --git a/include/json.hpp b/include/json.hpp
index cdb0b63..e8737e4 100644
--- a/include/json.hpp
+++ b/include/json.hpp
@@ -2773,6 +2773,49 @@ static constexpr string_t unescape_string(const string_t& str)
 
     return result;
 }
+
+namespace _jsonization_helper
+{
+    struct required_tag
+    {
+        constexpr static bool required = true;
+    };
+    struct optional_tag
+    {
+        constexpr static bool required = false;
+    };
+}
+
+struct bind_helper
+{
+    void __to_json(json::object&) const {}
+
+    bool __from_json(const json::object&) { return true; }
+
+    template <typename Tag, typename Var, typename... Rest>
+    void __to_json(json::object& obj, Tag, const Var& var, const char* name, Rest&&... rest) const
+    {
+        obj[name] = json::serialize<false>(var);
+        __to_json(obj, std::forward<Rest>(rest)...);
+    }
+
+    template <typename Tag, typename Var, typename... Rest>
+    bool __from_json(const json::object& raw, Tag, Var& var, const char* name, Rest&&... rest)
+    {
+        if (auto opt = raw.find(name)) {
+            if (!opt->is<Var>()) {
+                return false;
+            }
+            var = std::move(opt)->as<Var>();
+        } else {
+            if constexpr (Tag::required) {
+                return false;
+            }
+        }
+        return __from_json(raw, std::forward<Rest>(rest)...);
+    }
+};
+
 } // namespace json
 
 namespace json::_jsonization_helper
@@ -2917,3 +2960,16 @@ namespace json::_private_macro
     }
 
 #define MEO_OPTIONAL json::_jsonization_helper::next_is_optional(),
+#define MEO_REQ(var) json::_jsonization_helper::required_tag {}, var, #var
+#define MEO_OPT(var) json::_jsonization_helper::optional_tag {}, var, #var
+#define MEO_JSONBIND(...)                                  \
+    json::object to_json() const                           \
+    {                                                      \
+        json::object res;                                  \
+        bind_helper::__to_json(res, __VA_ARGS__);          \
+        return res;                                        \
+    }                                                      \
+    bool from_json(const json::object& raw)                 \
+    {                                                      \
+        return bind_helper::__from_json(raw, __VA_ARGS__); \
+    }
diff --git a/sample/sample.cpp b/sample/sample.cpp
index 73f48d2..da7e8ff 100644
--- a/sample/sample.cpp
+++ b/sample/sample.cpp
@@ -299,7 +299,7 @@ bool serializing()
 
 void test_jsonization()
 {
-    struct MyStruct
+    struct MyStruct : json::bind_helper
     {
         std::vector<int> vec;
         std::map<std::string, int> map;
@@ -308,6 +308,7 @@ void test_jsonization()
         double d = 0;
 
         MEO_JSONIZATION(vec, map, MEO_OPTIONAL i, MEO_OPTIONAL d);
+        MEO_JSONBIND(MEO_REQ(vec), MEO_REQ(map), MEO_OPT(i), MEO_OPT(d))
     };
 
     MyStruct a;
@@ -316,15 +317,29 @@ void test_jsonization()
     a.i = 100;
     a.d = 0.5;
 
-    json::object j = a.dump_to_json();
-    std::cout << j << std::endl;
+    // json::object j = a.dump_to_json();
+    // std::cout << j << std::endl;
 
-    // for test MEO_OPTIONAL
-    j.erase("i");
+    // // for test MEO_OPTIONAL
+    // j.erase("i");
 
-    MyStruct b;
-    bool loaded = b.load_from_json(j);
+    // MyStruct b;
+    // bool loaded = b.load_from_json(j);
 
-    std::cout << "loaded: " << loaded << std::endl;
-    std::cout << b.dump_to_json() << std::endl;
+    // std::cout << "loaded: " << loaded << std::endl;
+    // std::cout << b.dump_to_json() << std::endl;
+
+    {
+        json::object j = a.to_json();
+        std::cout << j << std::endl;
+
+        // for test MEO_OPTIONAL
+        j.erase("i");
+
+        MyStruct b;
+        bool loaded = b.from_json(j);
+
+        std::cout << "loaded: " << loaded << std::endl;
+        std::cout << b.to_json() << std::endl;
+    }
 }