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

#pragma once

#include "CoreMinimal.h"
#include "Templates/Casts.h"
#include "UObject/Package.h"
#include "Serialization/ArchiveReplaceObjectRef.h"

/*----------------------------------------------------------------------------
FArchiveReplaceOrClearExternalReferences.
----------------------------------------------------------------------------*/
/**
 * Identical to FArchiveReplaceObjectRef, but for references to private objects
 * in other packages we clear the reference instead of preserving it (unless it
 * makes it into the replacement map)
 */
template <class T>
class FArchiveReplaceOrClearExternalReferences: public FArchiveReplaceObjectRef<T>
{
    typedef FArchiveReplaceObjectRef<T> TSuper;

public:
    FArchiveReplaceOrClearExternalReferences(UObject* InSearchObject, const TMap<T*, T*>& InReplacementMap, UPackage* InDestPackage, bool bDelayStart = false)
        : TSuper(InSearchObject, InReplacementMap, false, false, false, true), DestPackage(InDestPackage)
    {
        if (!bDelayStart)
        {
            this->SerializeSearchObject();
        }
    }

    FArchive& operator<<(UObject*& Obj)
    {
        UObject* Resolved = Obj;
        TSuper::operator<<(Resolved);
        // if Resolved is a private object in another package just clear the reference:
        if (Resolved)
        {
            UObject* Outermost = Resolved->GetOutermost();
            if (Outermost)
            {
                UPackage* ObjPackage = dynamic_cast<UPackage*>(Outermost);
                if (ObjPackage)
                {
                    CA_SUPPRESS(6011);
                    if (ObjPackage != Obj &&
                        DestPackage != ObjPackage &&
                        !Obj->HasAnyFlags(RF_Public))
                    {
                        Resolved = nullptr;
                    }
                }
            }
        }
        Obj = Resolved;
        return *this;
    }

protected:
    /** Package that we are loading into, references to private objects in other packages will be cleared */
    UPackage* DestPackage;
};