// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include "CoreMinimal.h"
#include "Serialization/ArchiveUObject.h"
#include "UObject/UObjectAnnotation.h"
#include "Serialization/DuplicatedObject.h"
#include "Serialization/LargeMemoryData.h"
#include "Templates/RefCounting.h"
#include "UObject/UObjectThreadContext.h"

/*----------------------------------------------------------------------------
        FDuplicateDataReader.
----------------------------------------------------------------------------*/

/**
 * Reads duplicated objects from a memory buffer, replacing object references to duplicated objects.
 */
class FDuplicateDataReader: public FArchiveUObject
{
private:
    class FUObjectAnnotationSparse<FDuplicatedObject, false>& DuplicatedObjectAnnotation;
    const FLargeMemoryData& ObjectData;
    int64 Offset;

    /** Context for duplication */
    TRefCountPtr<FUObjectSerializeContext> DuplicateContext;

    //~ Begin FArchive Interface.

    virtual FArchive& operator<<(FName& N);
    virtual FArchive& operator<<(UObject*& Object);
    virtual FArchive& operator<<(FLazyObjectPtr& LazyObjectPtr);
    virtual FArchive& operator<<(FSoftObjectPath& SoftObjectPath);

    void SerializeFail();

    virtual void Serialize(void* Data, int64 Num)
    {
        if (ObjectData.Read(Data, Offset, Num))
        {
            Offset += Num;
        }
        else
        {
            SerializeFail();
        }
    }

    virtual void Seek(int64 InPos)
    {
        Offset = InPos;
    }

public:
    /**
     * Returns the name of the Archive.  Useful for getting the name of the package a struct or object
     * is in when a loading error occurs.
     *
     * This is overridden for the specific Archive Types
     **/
    virtual FString GetArchiveName() const { return TEXT("FDuplicateDataReader"); }

    virtual int64 Tell()
    {
        return Offset;
    }
    virtual int64 TotalSize()
    {
        return ObjectData.GetSize();
    }

    virtual void SetSerializeContext(FUObjectSerializeContext* InLoadContext) override
    {
        DuplicateContext = InLoadContext;
    }

    virtual FUObjectSerializeContext* GetSerializeContext() override
    {
        return DuplicateContext;
    }

    /**
     * Constructor
     *
     * @param	InDuplicatedObjectAnnotation		Annotation for storing a mapping from source to duplicated object
     * @param	InObjectData					Object data to read from
     */
    FDuplicateDataReader(FUObjectAnnotationSparse<FDuplicatedObject, false>& InDuplicatedObjectAnnotation, const FLargeMemoryData& InObjectData, uint32 InPortFlags, UObject* InDestOuter);
};