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

#pragma once

#include "Containers/Array.h"
#include "Containers/Set.h"
#include "Containers/Map.h"
#include "UObject/NameTypes.h"
#include "Serialization/FileRegions.h"
#include "Misc/DateTime.h"
#include "ObjectMacros.h"

#if !defined(UE_WITH_SAVEPACKAGE)
#define UE_WITH_SAVEPACKAGE 1
#endif

class FArchive;
class FIoBuffer;
class FPackageStoreBulkDataManifest;
class FSavePackageContext;
class FArchiveDiffMap;
class FOutputDevice;

/**
 * Struct to encapsulate arguments specific to saving one package
 */
struct FPackageSaveInfo
{
    class UPackage* Package = nullptr;
    class UObject* Asset    = nullptr;
    FString Filename;
};

/**
 * Struct to encapsulate UPackage::Save arguments.
 * These arguments are shared between packages when saving multiple packages concurrently.
 */
struct FSavePackageArgs
{
    class ITargetPlatform* TargetPlatform = nullptr;
    EObjectFlags TopLevelFlags            = RF_NoFlags;
    uint32 SaveFlags                      = 0;
    bool bForceByteSwapping               = false;  // for FLinkerSave
    bool bWarnOfLongFilename              = false;
    bool bSlowTask                        = true;
    FDateTime FinalTimeStamp;
    FOutputDevice* Error                    = nullptr;
    FArchiveDiffMap* DiffMap                = nullptr;
    FSavePackageContext* SavePackageContext = nullptr;
};

class FPackageStoreWriter
{
public:
    COREUOBJECT_API FPackageStoreWriter();
    COREUOBJECT_API virtual ~FPackageStoreWriter();

    struct HeaderInfo
    {
        FName PackageName;
        FString LooseFilePath;
    };

    /** Write 'uasset' data
     */
    virtual void WriteHeader(const HeaderInfo& Info, const FIoBuffer& HeaderData) = 0;

    struct ExportsInfo
    {
        FName PackageName;
        FString LooseFilePath;
        uint64 RegionsOffset;

        TArray<FIoBuffer> Exports;
    };

    /** Write 'uexp' data
     */
    virtual void WriteExports(const ExportsInfo& Info, const FIoBuffer& ExportsData, const TArray<FFileRegion>& FileRegions) = 0;

    struct FBulkDataInfo
    {
        enum EType
        {
            Standard,
            Mmap,
            Optional
        };

        FName PackageName;
        EType BulkdataType = Standard;
        FString LooseFilePath;
    };

    /** Write 'ubulk' data
     */
    virtual void WriteBulkdata(const FBulkDataInfo& Info, const FIoBuffer& BulkData, const TArray<FFileRegion>& FileRegions) = 0;
};

class FLooseFileWriter: public FPackageStoreWriter
{
public:
    COREUOBJECT_API FLooseFileWriter();
    COREUOBJECT_API ~FLooseFileWriter();

    COREUOBJECT_API virtual void WriteHeader(const HeaderInfo& Info, const FIoBuffer& HeaderData) override;
    COREUOBJECT_API virtual void WriteExports(const ExportsInfo& Info, const FIoBuffer& ExportsData, const TArray<FFileRegion>& FileRegions) override;
    COREUOBJECT_API virtual void WriteBulkdata(const FBulkDataInfo& Info, const FIoBuffer& BulkData, const TArray<FFileRegion>& FileRegions) override;

private:
};

class FSavePackageContext
{
public:
    FSavePackageContext(FPackageStoreWriter* InPackageStoreWriter, FPackageStoreBulkDataManifest* InBulkDataManifest, bool InbForceLegacyOffsets)
        : PackageStoreWriter(InPackageStoreWriter), BulkDataManifest(InBulkDataManifest), bForceLegacyOffsets(InbForceLegacyOffsets)
    {
    }

    COREUOBJECT_API ~FSavePackageContext();

    FPackageStoreWriter* PackageStoreWriter;
    FPackageStoreBulkDataManifest* BulkDataManifest;
    bool bForceLegacyOffsets;
};