UnrealEngineUWP/Engine/Source/Runtime/Serialization/Public/Backends/JsonStructSerializerBackend.h

// Copyright 1998-2016 Epic Games, Inc. All Rights Reserved.

#pragma once

#include "IStructSerializerBackend.h"
#include "Json.h"


// forward declarations
class UProperty;
class UStruct;


/**
 * Implements a writer for UStruct serialization using Json.
 *
 * Note: The underlying Json serializer is currently hard-coded to use UCS2CHAR and pretty-print.
 * This is because the current JsonWriter API does not allow writers to be substituted since it's
 * all based on templates. At some point we will refactor the low-level Json API to provide more
 * flexibility for serialization.
 */
class SERIALIZATION_API FJsonStructSerializerBackend
	: public IStructSerializerBackend
{
public:

	/**
	 * Creates and initializes a new instance.
	 *
	 * @param Archive The archive to serialize into.
	 */
	FJsonStructSerializerBackend( FArchive& Archive )
		: JsonWriter(TJsonWriter<UCS2CHAR>::Create(&Archive))
	{ }

public:

	// IStructSerializerBackend interface

	virtual void BeginArray(const FStructSerializerState& State) override;
	virtual void BeginStructure(const FStructSerializerState& State) override;
	virtual void EndArray(const FStructSerializerState& State) override;
	virtual void EndStructure(const FStructSerializerState& State) override;
	virtual void WriteComment(const FString& Comment) override;
	virtual void WriteProperty(const FStructSerializerState& State, int32 ArrayIndex = 0) override;

protected:

	// Allow access to the internal JsonWriter to subclasses
	TSharedRef<TJsonWriter<UCS2CHAR>>& GetWriter()
	{
		return JsonWriter;
	}

private:

	/** Holds the Json writer used for the actual serialization. */
	TSharedRef<TJsonWriter<UCS2CHAR>> JsonWriter;
};