text: /*
   * This source file is part of RmlUi, the HTML/CSS Interface Middleware
   *
   * For the latest information, see http://github.com/mikke89/RmlUi
   *
   * Copyright (c) 2008-2010 CodePoint Ltd, Shift Technology Ltd
   * Copyright (c) 2019 The RmlUi Team, and contributors
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   *
   */
  
  #ifndef RMLUI_CORE_DATATYPEREGISTER_H
  #define RMLUI_CORE_DATATYPEREGISTER_H
  
  #include "Header.h"
  #include "Types.h"
  #include "Traits.h"
  #include "DataTypes.h"
  #include "DataVariable.h"
  
  
  namespace Rml {
  
  template<typename T>
  struct is_builtin_data_scalar {
  	static constexpr bool value = std::is_arithmetic<T>::value
  		|| std::is_same<typename std::remove_const<T>::type, String>::value;
  };
  
  
  class RMLUICORE_API TransformFuncRegister {
  public:
  	void Register(const String& name, DataTransformFunc transform_func);
  	bool Call(const String& name, Variant& inout_result, const VariantList& arguments) const;
  
  private:
  	UnorderedMap<String, DataTransformFunc> transform_functions;
  };
  
  
  class RMLUICORE_API DataTypeRegister final : NonCopyMoveable {
  public:
  	DataTypeRegister();
  	~DataTypeRegister();
  
  	inline bool RegisterDefinition(FamilyId id, UniquePtr<VariableDefinition> definition)
  	{
  		const bool inserted = type_register.emplace(id, std::move(definition)).second;
  		return inserted;
  	}
  
  	template<typename T>
  	VariableDefinition* GetDefinition()
  	{
  		return GetDefinitionDetail<T>();
  	}
  
  	inline TransformFuncRegister* GetTransformFuncRegister() {
  		return &transform_register;
  	}
  
  private:
  	// Get definition for scalar types that can be assigned to and from Rml::Variant.
  	// We automatically register these when needed, so users don't have to register trivial types manually.
  	template<typename T, typename std::enable_if<!PointerTraits<T>::is_pointer::value && is_builtin_data_scalar<T>::value, int>::type = 0>
  	VariableDefinition* GetDefinitionDetail()
  	{
  		static_assert(!std::is_const<T>::value, "Data binding variables cannot point to constant variables.");
  		FamilyId id = Family<T>::Id();
  
  		auto result = type_register.emplace(id, nullptr);
  		bool inserted = result.second;
  		UniquePtr<VariableDefinition>& definition = result.first->second;
  
  		if (inserted)
  			definition = MakeUnique<ScalarDefinition<T>>();
  
  		return definition.get();
  	}
  
  	// Get definition for types that are not a built-in scalar.
  	// These must already have been registered by the user.
  	template<typename T, typename std::enable_if<!PointerTraits<T>::is_pointer::value && !is_builtin_data_scalar<T>::value, int>::type = 0>
  	VariableDefinition* GetDefinitionDetail()
  	{
  		FamilyId id = Family<T>::Id();
  		auto it = type_register.find(id);
  		if (it == type_register.end())
  		{
  			RMLUI_LOG_TYPE_ERROR(T, "Desired data type T not registered with the type register, please use the 'Register...()' functions before binding values, adding members, or registering arrays of non-scalar types.");
  			return nullptr;
  		}
  
  		return it->second.get();
  	}
  
  	// Get definition for pointer types, or create one as needed.
  	// This will create a wrapper definition that forwards the call to the definition of the underlying type.
  	template<typename T, typename std::enable_if<true, int>::type = 0>
  	VariableDefinition* GetDefinitionDetail()
  	{
  		static_assert(PointerTraits<T>::is_pointer::value, "Invalid pointer type provided.");
  
  		using UnderlyingType = typename PointerTraits<T>::element_type;
  		static_assert(!PointerTraits<UnderlyingType>::is_pointer::value, "Recursive pointer types (pointer to pointer) to data variables are disallowed.");
  		static_assert(!std::is_const<UnderlyingType>::value, "Pointer to a const data variable is not supported.");
  
  		// Get the underlying definition.
  		VariableDefinition* underlying_definition = GetDefinitionDetail<UnderlyingType>();
  		if (!underlying_definition)
  		{
  			RMLUI_LOG_TYPE_ERROR(T, "Underlying type of pointer not registered.");
  			return nullptr;
  		}
  
  		// Get or create the pointer wrapper definition.
  		FamilyId id = Family<T>::Id();
  
  		auto result = type_register.emplace(id, nullptr);
  		bool inserted = result.second;
  		UniquePtr<VariableDefinition>& definition = result.first->second;
  
  		if (inserted)
  			definition = MakeUnique<PointerDefinition<T>>(underlying_definition);
  
  		return definition.get();
  	}
  
  	UnorderedMap<FamilyId, UniquePtr<VariableDefinition>> type_register;
  	TransformFuncRegister transform_register;
  };
  
  
  } // namespace Rml
  #endif
  