Remove NodeDataModel::clone() (paceholder#164)

facontidavide · paceholder · commit a8264e391d1a · 2018-05-11T11:00:30.000+02:00
* removed NodeDataModel::clone(), using a more classic Factory/Builder pattern.

* trying to make visual studio happy

* Allow the DataModelRegistry to use static method Name() if defined

* use modern type_traits
diff --git a/examples/calculator/AdditionModel.hpp b/examples/calculator/AdditionModel.hpp
@@ -28,10 +28,6 @@ class AdditionModel : public MathOperationDataModel
   name() const override
   { return QStringLiteral("Addition"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<AdditionModel>(); }
-
 private:
 
   void
diff --git a/examples/calculator/DivisionModel.hpp b/examples/calculator/DivisionModel.hpp
@@ -56,10 +56,6 @@ class DivisionModel : public MathOperationDataModel
   name() const override
   { return QStringLiteral("Division"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<DivisionModel>(); }
-
 private:
 
   void
diff --git a/examples/calculator/ModuloModel.hpp b/examples/calculator/ModuloModel.hpp
@@ -67,10 +67,6 @@ class ModuloModel
   name() const override
   { return QStringLiteral("Modulo"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<ModuloModel>(); }
-
 public:
 
   QJsonObject
diff --git a/examples/calculator/MultiplicationModel.hpp b/examples/calculator/MultiplicationModel.hpp
@@ -28,10 +28,6 @@ class MultiplicationModel : public MathOperationDataModel
   name() const override
   { return QStringLiteral("Multiplication"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<MultiplicationModel>(); }
-
 private:
 
   void
diff --git a/examples/calculator/NumberDisplayDataModel.hpp b/examples/calculator/NumberDisplayDataModel.hpp
@@ -40,10 +40,6 @@ class NumberDisplayDataModel : public NodeDataModel
   name() const override
   { return QStringLiteral("Result"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<NumberDisplayDataModel>(); }
-
 public:
 
   unsigned int
diff --git a/examples/calculator/NumberSourceDataModel.hpp b/examples/calculator/NumberSourceDataModel.hpp
@@ -43,10 +43,6 @@ class NumberSourceDataModel
   name() const override
   { return QStringLiteral("NumberSource"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<NumberSourceDataModel>(); }
-
 public:
 
   QJsonObject
diff --git a/examples/calculator/SubtractionModel.hpp b/examples/calculator/SubtractionModel.hpp
@@ -57,10 +57,6 @@ class SubtractionModel : public MathOperationDataModel
   name() const override
   { return QStringLiteral("Subtraction"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<SubtractionModel>(); }
-
 private:
 
   void
diff --git a/examples/connection_colors/models.hpp b/examples/connection_colors/models.hpp
@@ -64,10 +64,6 @@ class NaiveDataModel : public NodeDataModel
   name() const override
   { return QString("NaiveDataModel"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<NaiveDataModel>(); }
-
 public:
 
   unsigned int
diff --git a/examples/example2/TextDisplayDataModel.hpp b/examples/example2/TextDisplayDataModel.hpp
@@ -35,13 +35,13 @@ class TextDisplayDataModel : public NodeDataModel
   bool
   captionVisible() const override { return false; }
 
-  QString
-  name() const override
+  static QString
+  Name()
   { return QString("TextDisplayDataModel"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<TextDisplayDataModel>(); }
+  QString
+  name() const override
+  { return TextDisplayDataModel::Name(); }
 
 public:
 
diff --git a/examples/example2/TextSourceDataModel.hpp b/examples/example2/TextSourceDataModel.hpp
@@ -35,13 +35,13 @@ class TextSourceDataModel : public NodeDataModel
   bool
   captionVisible() const override { return false; }
 
-  QString
-  name() const override
+  static QString
+  Name()
   { return QString("TextSourceDataModel"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<TextSourceDataModel>(); }
+  QString
+  name() const override
+  { return TextSourceDataModel::Name(); }
 
 public:
 
diff --git a/examples/images/ImageLoaderModel.hpp b/examples/images/ImageLoaderModel.hpp
@@ -38,10 +38,6 @@ class ImageLoaderModel : public NodeDataModel
   QString
   name() const override { return QString("ImageLoaderModel"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<ImageLoaderModel>(); }
-
 public:
 
   virtual QString
diff --git a/examples/images/ImageShowModel.hpp b/examples/images/ImageShowModel.hpp
@@ -37,10 +37,6 @@ class ImageShowModel : public NodeDataModel
   name() const override
   { return QString("ImageShowModel"); }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  { return std::make_unique<ImageShowModel>(); }
-
 public:
 
   virtual QString
diff --git a/examples/styles/models.hpp b/examples/styles/models.hpp
@@ -52,12 +52,6 @@ class MyDataModel : public NodeDataModel
     return QString("MyDataModel");
   }
 
-  std::unique_ptr<NodeDataModel>
-  clone() const override
-  {
-    return std::make_unique<MyDataModel>();
-  }
-
 public:
 
   QJsonObject
diff --git a/include/nodes/internal/DataModelRegistry.hpp b/include/nodes/internal/DataModelRegistry.hpp
@@ -1,6 +1,8 @@
 #pragma once
 
 #include <set>
+#include <memory>
+#include <functional>
 #include <unordered_map>
 #include <vector>
 
@@ -31,7 +33,8 @@ class NODE_EDITOR_PUBLIC DataModelRegistry
 public:
 
   using RegistryItemPtr     = std::unique_ptr<NodeDataModel>;
-  using RegisteredModelsMap = std::unordered_map<QString, RegistryItemPtr>;
+  using RegistryItemCreator = std::function<RegistryItemPtr()>;
+  using RegisteredModelCreatorsMap = std::unordered_map<QString, RegistryItemCreator>;
   using RegisteredModelsCategoryMap = std::unordered_map<QString, QString>;
   using CategoriesSet = std::set<QString>;
 
@@ -49,28 +52,24 @@ class NODE_EDITOR_PUBLIC DataModelRegistry
 public:
 
   template<typename ModelType>
-  void registerModel(std::unique_ptr<ModelType> uniqueModel =
-                       detail::make_unique<ModelType>(),
+  void registerModel(RegistryItemCreator creator,
                      QString const &category = "Nodes")
   {
-    static_assert(std::is_base_of<NodeDataModel, ModelType>::value,
-                  "Must pass a subclass of NodeDataModel to registerModel");
-
-    QString const name = uniqueModel->name();
+    registerModelImpl<ModelType>(std::move(creator), category);
+  }
 
-    if (_registeredModels.count(name) == 0)
-    {
-      _registeredModels[name] = std::move(uniqueModel);
-      _categories.insert(category);
-      _registeredModelsCategory[name] = category;
-    }
+  template<typename ModelType>
+  void registerModel(QString const &category = "Nodes")
+  {
+    RegistryItemCreator creator = [](){ return std::make_unique<ModelType>(); };
+    registerModelImpl<ModelType>(std::move(creator), category);
   }
 
-  //Parameter order alias, so a category can be set without forcing to manually pass a model instance
   template<typename ModelType>
-  void registerModel(QString const &category, std::unique_ptr<ModelType> uniqueModel = detail::make_unique<ModelType>())
+  void registerModel(QString const &category,
+                     RegistryItemCreator creator)
   {
-    registerModel<ModelType>(std::move(uniqueModel), category);
+    registerModelImpl<ModelType>(std::move(creator), category);
   }
 
   void registerTypeConverter(TypeConverterId const & id,
@@ -81,7 +80,7 @@ class NODE_EDITOR_PUBLIC DataModelRegistry
 
   std::unique_ptr<NodeDataModel>create(QString const &modelName);
 
-  RegisteredModelsMap const &registeredModels() const;
+  RegisteredModelCreatorsMap const &registeredModelCreators() const;
 
   RegisteredModelsCategoryMap const &registeredModelsCategoryAssociation() const;
 
@@ -96,8 +95,59 @@ class NODE_EDITOR_PUBLIC DataModelRegistry
 
   CategoriesSet _categories;
 
-  RegisteredModelsMap _registeredModels;
+  RegisteredModelCreatorsMap _registeredItemCreators;
 
   RegisteredTypeConvertersMap _registeredTypeConverters;
+
+private:
+
+  // If the registered ModelType class has the static member method
+  //
+  //      static Qstring Name();
+  //
+  // use it. Otherwise use the non-static method:
+  //
+  //       virtual QString name() const;
+
+  template <typename T, typename = void>
+  struct HasStaticMethodName
+      : std::false_type
+  {};
+
+  template <typename T>
+  struct HasStaticMethodName<T,
+          typename std::enable_if<std::is_same<decltype(T::Name()), QString>::value>::type>
+      : std::true_type
+  {};
+
+  template<typename ModelType>
+  typename std::enable_if< HasStaticMethodName<ModelType>::value>::type
+  registerModelImpl(RegistryItemCreator creator, QString const &category )
+  {
+    const QString name = ModelType::Name();
+    if (_registeredItemCreators.count(name) == 0)
+    {
+      _registeredItemCreators[name] = std::move(creator);
+      _categories.insert(category);
+      _registeredModelsCategory[name] = category;
+    }
+  }
+
+  template<typename ModelType>
+  typename std::enable_if< !HasStaticMethodName<ModelType>::value>::type
+  registerModelImpl(RegistryItemCreator creator, QString const &category )
+  {
+    const QString name = creator()->name();
+    if (_registeredItemCreators.count(name) == 0)
+    {
+      _registeredItemCreators[name] = std::move(creator);
+      _categories.insert(category);
+      _registeredModelsCategory[name] = category;
+    }
+  }
+
 };
+
+
+
 }
diff --git a/include/nodes/internal/NodeDataModel.hpp b/include/nodes/internal/NodeDataModel.hpp
@@ -57,10 +57,6 @@ class NODE_EDITOR_PUBLIC NodeDataModel
   virtual QString
   name() const = 0;
 
-  /// Function creates instances of a model stored in DataModelRegistry
-  virtual std::unique_ptr<NodeDataModel>
-  clone() const = 0;
-
 public:
 
   QJsonObject
diff --git a/src/DataModelRegistry.cpp b/src/DataModelRegistry.cpp
@@ -12,22 +12,22 @@ std::unique_ptr<NodeDataModel>
 DataModelRegistry::
 create(QString const &modelName)
 {
-  auto it = _registeredModels.find(modelName);
+  auto it = _registeredItemCreators.find(modelName);
 
-  if (it != _registeredModels.end())
+  if (it != _registeredItemCreators.end())
   {
-    return it->second->clone();
+    return it->second();
   }
 
   return nullptr;
 }
 
 
-DataModelRegistry::RegisteredModelsMap const &
+DataModelRegistry::RegisteredModelCreatorsMap const &
 DataModelRegistry::
-registeredModels() const
+registeredModelCreators() const
 {
-  return _registeredModels;
+  return _registeredItemCreators;
 }
 
 
