Overhaul some parts of serialization

base/lib/iscore/serialization/DataStreamVisitor.hpp

@@ -88,7 +88,7 @@ class Visitor<Reader<DataStream>> : public AbstractVisitor
             readFrom(obj.id());
         }
 
-        template<typename T>
+        template<typename T, std::enable_if_t<!std::is_enum<T>::value>* = nullptr>
         void readFrom(const T&);
 
         template<typename T>
@@ -99,6 +99,12 @@ class Visitor<Reader<DataStream>> : public AbstractVisitor
         template<typename... Args>
         void readFrom(const eggs::variants::variant<Args...>&);
 
+        template<typename T, std::enable_if_t<std::is_enum<T>::value>* = nullptr>
+        void readFrom(const T& elt)
+        {
+            m_stream << (int32_t) elt;
+        }
+
         /**
          * @brief insertDelimiter
          *
@@ -162,7 +168,7 @@ class Visitor<Writer<DataStream>> : public AbstractVisitor
             obj.setId(std::move(id));
         }
 
-        template<typename T>
+        template<typename T, std::enable_if_t<!std::is_enum<T>::value>* = nullptr>
         void writeTo(T&);
 
         template<typename T>
@@ -173,7 +179,13 @@ class Visitor<Writer<DataStream>> : public AbstractVisitor
         template<typename... Args>
         void writeTo(eggs::variants::variant<Args...>&);
 
-
+        template<typename T, std::enable_if_t<std::is_enum<T>::value>* = nullptr>
+        void writeTo(T& elt)
+        {
+            int32_t e;
+            m_stream >> e;
+            elt = static_cast<T>(e);
+        }
 
         /**
          * @brief checkDelimiter

base/lib/iscore/serialization/JSONValueVisitor.hpp

@@ -6,6 +6,7 @@
 #include <QVector>
 #include <QMap>
 
+
 template<typename T>
 T fromJsonObject(QJsonValue&& json);
 
@@ -36,9 +37,15 @@ class Visitor<Reader<JSONValue>> : public AbstractVisitor
 
         VisitorVariant toVariant() { return {*this, JSONValue::type()}; }
 
-        template<typename T>
+        template<typename T, std::enable_if_t<!std::is_enum<T>::value>* = nullptr>
         void readFrom(const T&);
 
+        template<typename T, std::enable_if_t<std::is_enum<T>::value>* = nullptr>
+        void readFrom(const T& elt)
+        {
+            val = (int32_t) elt;
+        }
+
         template<typename T>
         void readFrom(const Id<T>& obj)
         {
@@ -66,9 +73,15 @@ class Visitor<Writer<JSONValue>> : public AbstractVisitor
         Visitor<Writer<JSONValue>> (QJsonValue&& obj) :
                                val{std::move(obj) }  {}
 
-        template<typename T>
+        template<typename T, std::enable_if_t<!std::is_enum<T>::value>* = nullptr>
         void writeTo(T&);
 
+        template<typename T, std::enable_if_t<std::is_enum<T>::value>* = nullptr>
+        void writeTo(T& elt)
+        {
+            elt = static_cast<T>(val.toInt());
+        }
+
         template<typename T>
         void writeTo(Id<T>& obj)
         {

base/lib/iscore/serialization/VisitorInterface.hpp

@@ -59,3 +59,25 @@ using enable_if_deserializer = typename std::enable_if_t<std::decay<Deserializer
 #define ISCORE_SERIALIZE_FRIENDS(Type, Serializer) \
     friend void Visitor<Reader< Serializer >>::readFrom< Type > (const Type &); \
     friend void Visitor<Writer< Serializer >>::writeTo< Type > (Type &);
+
+
+// Inherit from this to have
+// the type treated as a value in the serialization context. Useful
+// for choice between JSONObject / JSONValue
+template<typename T>
+struct is_value_tag {
+        static const constexpr bool value = false;
+};
+#define ISCORE_DECL_VALUE_TYPE(Type) \
+    template<> struct is_value_tag<Type> { static const constexpr bool value = true; };
+
+template<typename T>
+struct is_value_t
+{
+    static const constexpr bool value{
+        std::is_arithmetic<T>::value
+     || std::is_enum<T>::value
+     || is_value_tag<T>::value
+    };
+};
+

base/lib/iscore/tools/VariantBasedNode.hpp

@@ -124,6 +124,31 @@ void Visitor<Writer<DataStream>>::writeTo(eggs::variant<Args...>& var)
 template<typename T>
 class TypeToName;
 
+// This part is required because it isn't as straightforward to save variant data
+// in JSON as it is to save it in a DataStream.
+// Basically, each variant member has an associated name that will be the
+// key in the JSON parent object. This name is defined by specializing
+// template<> class TypeToName<T>.
+// For instance:
+// template<> class TypeToName<iscore::Address>
+// { public: static constexpr const char * name() { return "Address"; } };
+
+// This allows easy store and retrieval under a familiar name
+
+
+
+// The _eggs_impl functions are because enum's don't need full-fledged objects in json.
+template<typename T, std::enable_if_t<!is_value_t<T>::value>* = nullptr>
+QJsonValue readFrom_eggs_impl(const T& res)
+{
+    return toJsonObject(res);
+}
+template<typename T, std::enable_if_t<is_value_t<T>::value>* = nullptr>
+QJsonValue readFrom_eggs_impl(const T& res)
+{
+    return toJsonValue(res);
+}
+
 template<typename... Args>
 void Visitor<Reader<JSONObject>>::readFrom(const eggs::variant<Args...>& var)
 {
@@ -139,13 +164,27 @@ void Visitor<Reader<JSONObject>>::readFrom(const eggs::variant<Args...>& var)
 
             if(auto res = var.template target<current_type>())
             {
-                this->m_obj[TypeToName<current_type>::name()] = toJsonObject(*res);
+                this->m_obj[TypeToName<current_type>::name()] = readFrom_eggs_impl(*res);
                 done = true;
             }
         });
     }
 }
 
+/**
+ * These two methods are because enum's don't need full-fledged objects.
+ */
+template<typename T, std::enable_if_t<!is_value_t<T>::value>* = nullptr>
+auto writeTo_eggs_impl(const QJsonValue& res)
+{
+    return fromJsonObject<T>(res.toObject());
+}
+template<typename T, std::enable_if_t<is_value_t<T>::value>* = nullptr>
+auto writeTo_eggs_impl(const QJsonValue& res)
+{
+    return fromJsonValue<T>(res);
+}
+
 template<typename... Args>
 void Visitor<Writer<JSONObject>>::writeTo(eggs::variant<Args...>& var)
 {
@@ -158,8 +197,8 @@ void Visitor<Writer<JSONObject>>::writeTo(eggs::variant<Args...>& var)
 
         if(m_obj.contains(TypeToName<current_type>::name()))
         {
-            typename std::remove_reference<decltype(elt)>::type data;
-            fromJsonObject(m_obj[TypeToName<current_type>::name()].toObject(), data);
+            current_type data = writeTo_eggs_impl<current_type>(m_obj[TypeToName<current_type>::name()]);
+
             var = data;
             done = true;
         }

base/plugins/iscore-lib-state/CMakeLists.txt

@@ -16,13 +16,17 @@ include_directories("${CMAKE_CURRENT_SOURCE_DIR}")
 set(SRCS
 "${CMAKE_CURRENT_SOURCE_DIR}/State/AddressSerialization.cpp"
 "${CMAKE_CURRENT_SOURCE_DIR}/State/ValueSerialization.cpp"
+"${CMAKE_CURRENT_SOURCE_DIR}/State/RelationSerialization.cpp"
 "${CMAKE_CURRENT_SOURCE_DIR}/State/MessageSerialization.cpp"
 "${CMAKE_CURRENT_SOURCE_DIR}/State/DynamicStateSerialization.cpp"
 "${CMAKE_CURRENT_SOURCE_DIR}/State/StateSerialization.cpp"
 
 "${CMAKE_CURRENT_SOURCE_DIR}/State/Address.cpp"
+"${CMAKE_CURRENT_SOURCE_DIR}/State/Value.cpp"
+"${CMAKE_CURRENT_SOURCE_DIR}/State/Relation.cpp"
 "${CMAKE_CURRENT_SOURCE_DIR}/State/Expression.cpp"
 "${CMAKE_CURRENT_SOURCE_DIR}/State/ExpressionParser.cpp"
+"${CMAKE_CURRENT_SOURCE_DIR}/State/ExpressionSerialization.cpp"
 "${CMAKE_CURRENT_SOURCE_DIR}/State/StateItemModel.cpp"
 
 "${CMAKE_CURRENT_SOURCE_DIR}/State/Widgets/AddressLineEdit.cpp"