JsonStringifyStructuredArchive.h

Go to the documentation of this file.

// Copyright Epic Games, Inc. All Rights Reserved.
 
#pragma once
 
#include "Serialization/StructuredArchiveFormatter.h"
#include "Serialization/CustomVersion.h"
#include "Serialization/MemoryWriter.h"
 
#if WITH_TEXT_ARCHIVE_SUPPORT
 
namespace UE::Private
{
 
struct FJsonStringifyImpl;
 
/*
    FJsonStringifyStructuredArchive is an implementation detail of JsonObjectGraph. It provides support
    for saving the relatively rare data that provides a native Serialize(FStructuredArchive::FRecord) 
    but explicitly disables serialization of reflected properties and versioning data, which are handled
    by the root implementation
*/
struct FJsonStringifyStructuredArchive : private FStructuredArchiveFormatter
{
    FJsonStringifyStructuredArchive(
        const UObject* InObject, 
        int32 InitialIndentLevel, 
        FJsonStringifyImpl* InRootImpl,
        TArray<FCustomVersion>& InVersionsToHarvest,
        bool bFilterEditorOnly);
    
    // FMemoryWriter wants a byte array, so that's what we're working with at this level:
    TArray<uint8> ToJson();
 
    // Unsure if we want to use the structured archive for FText or the string encoding
    // long term, this provides us the option:
    static void WriteTextValueInline(FText Value, int32 IndentLevel, FArchive& ToWriter);
    // FCustomVersion is best encoded via operator<<(FStructuredArchive::FSlot Slot, FCustomVersion& Version):
    static void WriteCustomVersionValueInline(const TArray<FCustomVersion>& Version, int32 IndentLevel, FArchive& ToWriter);
private:
    FJsonStringifyStructuredArchive(FArchive& ToWriter, int32 InitialIndentLevel);
 
    virtual FArchive& GetUnderlyingArchive() override;
 
    virtual bool HasDocumentTree() const override;
 
    virtual void EnterRecord() override;
    virtual void LeaveRecord() override;
    virtual void EnterField(FArchiveFieldName Name) override;
    virtual void LeaveField() override;
    virtual bool TryEnterField(FArchiveFieldName Name, bool bEnterWhenSaving) override;
 
    virtual void EnterArray(int32& NumElements) override;
    virtual void LeaveArray() override;
    virtual void EnterArrayElement() override;
    virtual void LeaveArrayElement() override;
 
    virtual void EnterStream() override;
    virtual void LeaveStream() override;
    virtual void EnterStreamElement() override;
    virtual void LeaveStreamElement() override;
 
    virtual void EnterMap(int32& NumElements) override;
    virtual void LeaveMap() override;
    virtual void EnterMapElement(FString& Name) override;
    virtual void LeaveMapElement() override;
 
    virtual void EnterAttributedValue() override;
    virtual void EnterAttribute(FArchiveFieldName AttributeName) override;
    virtual void EnterAttributedValueValue() override;
    virtual void LeaveAttribute() override;
    virtual void LeaveAttributedValue() override;
    virtual bool TryEnterAttribute(FArchiveFieldName AttributeName, bool bEnterWhenSaving) override;
 
    virtual bool TryEnterAttributedValueValue() override;
 
    virtual void Serialize(uint8& Value) override;
    virtual void Serialize(uint16& Value) override;
    virtual void Serialize(uint32& Value) override;
    virtual void Serialize(uint64& Value) override;
    virtual void Serialize(int8& Value) override;
    virtual void Serialize(int16& Value) override;
    virtual void Serialize(int32& Value) override;
    virtual void Serialize(int64& Value) override;
    virtual void Serialize(float& Value) override;
    virtual void Serialize(double& Value) override;
    virtual void Serialize(bool& Value) override;
    virtual void Serialize(UTF32CHAR& Value) override;
    virtual void Serialize(FString& Value) override;
    virtual void Serialize(FName& Value) override;
    virtual void Serialize(UObject*& Value) override;
#if WITH_VERSE_VM || defined(__INTELLISENSE__)
    virtual void Serialize(Verse::VCell*& Value) override;
#endif
    virtual void Serialize(FText& Value) override;
    virtual void Serialize(FWeakObjectPtr& Value) override;
    virtual void Serialize(FSoftObjectPtr& Value) override;
    virtual void Serialize(FSoftObjectPath& Value) override;
    virtual void Serialize(FLazyObjectPtr& Value) override;
    virtual void Serialize(FObjectPtr& Value) override;
    virtual void Serialize(TArray<uint8>& Value) override;
    virtual void Serialize(void* Data, uint64 DataSize) override;
 
    void Write(ANSICHAR Character);
 
    void Write(const ANSICHAR* Text);
    void Write(const FString& Text);
 
    void WriteFieldName(const TCHAR* Name);
    void WriteValue(const FString& Value);
 
    void WriteOptionalComma();
    void WriteOptionalNewline();
    void WriteOptionalAttributedBlockOpening();
    void WriteOptionalAttributedBlockValue();
    void WriteOptionalAttributedBlockClosing();
 
    void SerializeStringInternal(const FString& String);
 
    TArray<FCustomVersion>* VersionsToHarvest;
    TArray<ANSICHAR> Newline;
 
    TArray<int32> NumAttributesStack;
    TArray<int64> TextStartPosStack;
 
    const UObject* const Object;
    FJsonStringifyImpl* RootImpl;
 
    TArray<uint8> ResultBuff;
    FMemoryWriter Inner;
    FArchive* Override = nullptr;
 
    int64_t ScopeSkipCount = 0;
    int32_t IndentLevel = 0;
    bool bNeedsComma = false;
    bool bNeedsNewline = false;
};
 
}
 
#endif