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

#include "Editor.h"
#include "Factories/Factory.h"
#include "HAL/PlatformFilemanager.h"
#include "HAL/FileManager.h"
#include "Modules/ModuleManager.h"
#include "Containers/ArrayView.h"
#include "EditorReimportHandler.h"
#include "ISourceControlOperation.h"
#include "SourceControlOperations.h"
#include "ISourceControlProvider.h"
#include "ISourceControlModule.h"
#include "Factories/ReimportFbxSkeletalMeshFactory.h"
#include "Factories/ReimportFbxStaticMeshFactory.h"
#include "Factories/ReimportFbxSceneFactory.h"
#include "Factories/ReimportSoundFactory.h"
#include "Factories/ReimportTextureFactory.h"
#include "Factories/PhysicalMaterialMaskFactory.h"
#include "Engine/BlueprintGeneratedClass.h"
#include "Misc/ScopedSlowTask.h"
#include "UObject/UObjectIterator.h"
#include "EngineUtils.h"
#include "Misc/MessageDialog.h"
#include "UnrealEngine.h"

// needed for the RemotePropagator

#include "Engine/SimpleConstructionScript.h"
#include "Kismet2/BlueprintEditorUtils.h"
#include "Engine/InheritableComponentHandler.h"

#include "Interfaces/IMainFrameModule.h"

#if PLATFORM_WINDOWS
#include "Windows/WindowsHWrapper.h"
// For WAVEFORMATEXTENSIBLE
#include "Windows/AllowWindowsPlatformTypes.h"
#include <mmreg.h>
#include "Windows/HideWindowsPlatformTypes.h"
#endif

#include "DesktopPlatformModule.h"
#include "ObjectTools.h"

#include "AnalyticsEventAttribute.h"
#include "Interfaces/IAnalyticsProvider.h"
#include "EngineAnalytics.h"

// AIMdule

#include "Framework/Notifications/NotificationManager.h"
#include "Widgets/Notifications/SNotificationList.h"
#include "K2Node_AddComponent.h"

#include "AutoReimport/AutoReimportUtilities.h"
#include "AssetToolsModule.h"

#define LOCTEXT_NAMESPACE "UnrealEd.Editor"

PRAGMA_DISABLE_DEPRECATION_WARNINGS

FSimpleMulticastDelegate FEditorDelegates::NewCurrentLevel;
FEditorDelegates::FOnMapChanged FEditorDelegates::MapChange;
FSimpleMulticastDelegate FEditorDelegates::LayerChange;
FEditorDelegates::FOnModeChanged FEditorDelegates::ChangeEditorMode;
FSimpleMulticastDelegate FEditorDelegates::SurfProps;
FSimpleMulticastDelegate FEditorDelegates::SelectedProps;
FEditorDelegates::FOnFitTextureToSurface FEditorDelegates::FitTextureToSurface;
FSimpleMulticastDelegate FEditorDelegates::ActorPropertiesChange;
FSimpleMulticastDelegate FEditorDelegates::RefreshEditor;
FSimpleMulticastDelegate FEditorDelegates::RefreshAllBrowsers;
FSimpleMulticastDelegate FEditorDelegates::RefreshLayerBrowser;
FSimpleMulticastDelegate FEditorDelegates::RefreshLevelBrowser;
FSimpleMulticastDelegate FEditorDelegates::RefreshPrimitiveStatsBrowser;
FSimpleMulticastDelegate FEditorDelegates::LoadSelectedAssetsIfNeeded;
FSimpleMulticastDelegate FEditorDelegates::DisplayLoadErrors;
FEditorDelegates::FOnEditorModeTransitioned FEditorDelegates::EditorModeEnter;
FEditorDelegates::FOnEditorModeTransitioned FEditorDelegates::EditorModeExit;
FEditorDelegates::FOnEditorModeIDTransitioned FEditorDelegates::EditorModeIDEnter;
FEditorDelegates::FOnEditorModeIDTransitioned FEditorDelegates::EditorModeIDExit;
FEditorDelegates::FOnPIEEvent FEditorDelegates::PreBeginPIE;
FEditorDelegates::FOnPIEEvent FEditorDelegates::BeginPIE;
FEditorDelegates::FOnPIEEvent FEditorDelegates::PrePIEEnded;
FEditorDelegates::FOnPIEEvent FEditorDelegates::PostPIEStarted;
FEditorDelegates::FOnPIEEvent FEditorDelegates::EndPIE;
FEditorDelegates::FOnPIEEvent FEditorDelegates::PausePIE;
FEditorDelegates::FOnPIEEvent FEditorDelegates::ResumePIE;
FEditorDelegates::FOnPIEEvent FEditorDelegates::SingleStepPIE;
FEditorDelegates::FOnPIEEvent FEditorDelegates::OnPreSwitchBeginPIEAndSIE;
FEditorDelegates::FOnPIEEvent FEditorDelegates::OnSwitchBeginPIEAndSIE;
FEditorDelegates::FOnStandaloneLocalPlayEvent FEditorDelegates::BeginStandaloneLocalPlay;
FSimpleMulticastDelegate FEditorDelegates::PropertySelectionChange;
FSimpleMulticastDelegate FEditorDelegates::PostLandscapeLayerUpdated;
FEditorDelegates::FOnPreSaveWorld FEditorDelegates::PreSaveWorld;
FEditorDelegates::FOnPostSaveWorld FEditorDelegates::PostSaveWorld;
FEditorDelegates::FOnFinishPickingBlueprintClass FEditorDelegates::OnFinishPickingBlueprintClass;
FEditorDelegates::FOnNewAssetCreation FEditorDelegates::OnConfigureNewAssetProperties;
FEditorDelegates::FOnNewAssetCreation FEditorDelegates::OnNewAssetCreated;
FEditorDelegates::FOnAssetPreImport FEditorDelegates::OnAssetPreImport;
FEditorDelegates::FOnAssetPostImport FEditorDelegates::OnAssetPostImport;
FEditorDelegates::FOnAssetReimport FEditorDelegates::OnAssetReimport;
FEditorDelegates::FOnNewActorsDropped FEditorDelegates::OnNewActorsDropped;
FEditorDelegates::FOnGridSnappingChanged FEditorDelegates::OnGridSnappingChanged;
FSimpleMulticastDelegate FEditorDelegates::OnLightingBuildStarted;
FSimpleMulticastDelegate FEditorDelegates::OnLightingBuildKept;
FSimpleMulticastDelegate FEditorDelegates::OnLightingBuildFailed;
FSimpleMulticastDelegate FEditorDelegates::OnLightingBuildSucceeded;
FEditorDelegates::FOnApplyObjectToActor FEditorDelegates::OnApplyObjectToActor;
FEditorDelegates::FOnFocusViewportOnActors FEditorDelegates::OnFocusViewportOnActors;
FEditorDelegates::FOnMapOpened FEditorDelegates::OnMapOpened;
FEditorDelegates::FOnEditorCameraMoved FEditorDelegates::OnEditorCameraMoved;
FEditorDelegates::FOnDollyPerspectiveCamera FEditorDelegates::OnDollyPerspectiveCamera;
FSimpleMulticastDelegate FEditorDelegates::OnShutdownPostPackagesSaved;
FEditorDelegates::FOnAssetsCanDelete FEditorDelegates::OnAssetsCanDelete;
FEditorDelegates::FOnAssetsAddExtraObjectsToDelete FEditorDelegates::OnAssetsAddExtraObjectsToDelete;
FEditorDelegates::FOnAssetsPreDelete FEditorDelegates::OnAssetsPreDelete;
FEditorDelegates::FOnAssetsDeleted FEditorDelegates::OnAssetsDeleted;
FEditorDelegates::FOnAssetDragStarted FEditorDelegates::OnAssetDragStarted;
FSimpleMulticastDelegate FEditorDelegates::OnActionAxisMappingsChanged;
FEditorDelegates::FOnAddLevelToWorld FEditorDelegates::OnAddLevelToWorld;
FEditorDelegates::FOnEditCutActorsBegin FEditorDelegates::OnEditCutActorsBegin;
FEditorDelegates::FOnEditCutActorsEnd FEditorDelegates::OnEditCutActorsEnd;
FEditorDelegates::FOnEditCopyActorsBegin FEditorDelegates::OnEditCopyActorsBegin;
FEditorDelegates::FOnEditCopyActorsEnd FEditorDelegates::OnEditCopyActorsEnd;
FEditorDelegates::FOnEditPasteActorsBegin FEditorDelegates::OnEditPasteActorsBegin;
FEditorDelegates::FOnEditPasteActorsEnd FEditorDelegates::OnEditPasteActorsEnd;
FEditorDelegates::FOnDuplicateActorsBegin FEditorDelegates::OnDuplicateActorsBegin;
FEditorDelegates::FOnDuplicateActorsEnd FEditorDelegates::OnDuplicateActorsEnd;
FEditorDelegates::FOnDeleteActorsBegin FEditorDelegates::OnDeleteActorsBegin;
FEditorDelegates::FOnDeleteActorsEnd FEditorDelegates::OnDeleteActorsEnd;
FEditorDelegates::FOnOpenReferenceViewer FEditorDelegates::OnOpenReferenceViewer;
FEditorDelegates::FOnViewAssetIdentifiers FEditorDelegates::OnOpenSizeMap;
FEditorDelegates::FOnViewAssetIdentifiers FEditorDelegates::OnOpenAssetAudit;
FEditorDelegates::FOnViewAssetIdentifiers FEditorDelegates::OnEditAssetIdentifiers;

PRAGMA_ENABLE_DEPRECATION_WARNINGS

/*-----------------------------------------------------------------------------
        Globals.
-----------------------------------------------------------------------------*/

IMPLEMENT_STRUCT(SlatePlayInEditorInfo);

//////////////////////////////////////////////////////////////////////////
// FReimportManager

FReimportManager* FReimportManager::Instance()
{
    static FReimportManager Inst;
    return &Inst;
}

void FReimportManager::RegisterHandler(FReimportHandler& InHandler)
{
    Handlers.AddUnique(&InHandler);
    bHandlersNeedSorting = true;
}

void FReimportManager::UnregisterHandler(FReimportHandler& InHandler)
{
    Handlers.Remove(&InHandler);
}

bool FReimportManager::CanReimport(UObject* Obj, TArray<FString>* ReimportSourceFilenames) const
{
    if (Obj)
    {
        TArray<FString> SourceFilenames;
        for (int32 HandlerIndex = 0; HandlerIndex < Handlers.Num(); ++HandlerIndex)
        {
            SourceFilenames.Empty();
            if (Handlers[HandlerIndex]->CanReimport(Obj, SourceFilenames))
            {
                if (ReimportSourceFilenames != nullptr)
                {
                    (*ReimportSourceFilenames) = SourceFilenames;
                }

                return true;
            }
        }
    }

    if (ReimportSourceFilenames != nullptr)
    {
        ReimportSourceFilenames->Empty();
    }

    return false;
}

void FReimportManager::UpdateReimportPaths(UObject* Obj, const TArray<FString>& InFilenames)
{
    if (Obj)
    {
        SortHandlersIfNeeded();

        TArray<FString> UnusedExistingFilenames;
        auto* Handler = Handlers.FindByPredicate([&](FReimportHandler* InHandler)
                                                 {
                                                     return InHandler->CanReimport(Obj, UnusedExistingFilenames);
                                                 });
        if (Handler)
        {
            (*Handler)->SetReimportPaths(Obj, InFilenames);
            Obj->MarkPackageDirty();
        }
    }
}

void FReimportManager::UpdateReimportPath(UObject* Obj, const FString& Filename, int32 SourceFileIndex)
{
    if (Obj)
    {
        SortHandlersIfNeeded();

        TArray<FString> UnusedExistingFilenames;
        auto* Handler = Handlers.FindByPredicate([&](FReimportHandler* InHandler)
                                                 {
                                                     return InHandler->CanReimport(Obj, UnusedExistingFilenames);
                                                 });
        if (Handler)
        {
            if (SourceFileIndex == INDEX_NONE)
            {
                TArray<FString> Filenames;
                Filenames.Add(Filename);
                (*Handler)->SetReimportPaths(Obj, Filenames);
            }
            else
            {
                (*Handler)->SetReimportPaths(Obj, Filename, SourceFileIndex);
            }
            Obj->MarkPackageDirty();
        }
    }
}

bool FReimportManager::Reimport(UObject* Obj, bool bAskForNewFileIfMissing, bool bShowNotification, FString PreferredReimportFile, FReimportHandler* SpecifiedReimportHandler, int32 SourceFileIndex, bool bForceNewFile /*= false*/, bool bAutomated /*= false*/)
{
    // Warn that were about to reimport, so prep for it
    PreReimport.Broadcast(Obj);

    bool bSuccess = false;
    if (Obj)
    {
        SortHandlersIfNeeded();

        bool bValidSourceFilename = false;
        TArray<FString> SourceFilenames;

        FReimportHandler* CanReimportHandler = SpecifiedReimportHandler;
        if (CanReimportHandler)
        {
            CanReimportHandler->SetPreferredReimportPath(PreferredReimportFile);
        }
        if (CanReimportHandler == nullptr || !CanReimportHandler->CanReimport(Obj, SourceFilenames))
        {
            for (int32 HandlerIndex = 0; HandlerIndex < Handlers.Num(); ++HandlerIndex)
            {
                SourceFilenames.Empty();
                Handlers[HandlerIndex]->SetPreferredReimportPath(PreferredReimportFile);
                if (Handlers[HandlerIndex]->CanReimport(Obj, SourceFilenames))
                {
                    CanReimportHandler = Handlers[HandlerIndex];
                    break;
                }
            }
        }

        if (CanReimportHandler != nullptr)
        {
            TArray<int32> MissingFileIndex;

            // Check all filenames for missing files
            bool bMissingFiles = false;
            if (!bForceNewFile && SourceFilenames.Num() > 0)
            {
                for (int32 FileIndex = 0; FileIndex < SourceFilenames.Num(); ++FileIndex)
                {
                    if (SourceFilenames[FileIndex].IsEmpty() || IFileManager::Get().FileSize(*SourceFilenames[FileIndex]) == INDEX_NONE || (bForceNewFile && SourceFileIndex == FileIndex))
                    {
                        if (SourceFileIndex == INDEX_NONE || SourceFileIndex == FileIndex)
                        {
                            MissingFileIndex.AddUnique(FileIndex);
                            bMissingFiles = true;
                        }
                    }
                }
            }
            else
            {
                int32 RealSourceFileIndex = SourceFileIndex == INDEX_NONE ? 0 : SourceFileIndex;
                if (bForceNewFile)
                {
                    if (SourceFilenames.IsValidIndex(RealSourceFileIndex))
                    {
                        SourceFilenames[RealSourceFileIndex].Empty();
                    }
                    else
                    {
                        // Add the missing entries
                        SourceFilenames.AddDefaulted(RealSourceFileIndex - (SourceFilenames.Num() - 1));
                    }
                    bAskForNewFileIfMissing = true;
                }

                MissingFileIndex.AddUnique(RealSourceFileIndex);
                bMissingFiles = true;
            }

            bValidSourceFilename = true;
            if ((bAskForNewFileIfMissing || !PreferredReimportFile.IsEmpty()) && bMissingFiles)
            {
                if (!bAskForNewFileIfMissing && !PreferredReimportFile.IsEmpty())
                {
                    SourceFilenames.Empty();
                    SourceFilenames.Add(PreferredReimportFile);
                }
                else
                {
                    for (int32 FileIndex: MissingFileIndex)
                    {
                        GetNewReimportPath(Obj, SourceFilenames, FileIndex);
                    }
                }
                bool bAllSourceFileEmpty = true;
                for (int32 SourceIndex = 0; SourceIndex < SourceFilenames.Num(); ++SourceIndex)
                {
                    if (!SourceFilenames[SourceIndex].IsEmpty())
                    {
                        bAllSourceFileEmpty = false;
                        break;
                    }
                }
                if (SourceFilenames.Num() == 0 || bAllSourceFileEmpty)
                {
                    // Failed to specify a new filename. Don't show a notification of the failure since the user exited on his own
                    bValidSourceFilename = false;
                    bShowNotification    = false;
                    SourceFilenames.Empty();
                }
                else
                {
                    // A new filename was supplied, update the path
                    for (int32 SourceIndex = 0; SourceIndex < SourceFilenames.Num(); ++SourceIndex)
                    {
                        if (!SourceFilenames[SourceIndex].IsEmpty())
                        {
                            CanReimportHandler->SetReimportPaths(Obj, SourceFilenames[SourceIndex], SourceIndex);
                        }
                    }
                }
            }
            else if (!PreferredReimportFile.IsEmpty() && !SourceFilenames.Contains(PreferredReimportFile))
            {
                // Reimporting the asset from a new file
                CanReimportHandler->SetReimportPaths(Obj, PreferredReimportFile, SourceFileIndex);
            }

            if (bValidSourceFilename)
            {
                // Do the reimport
                const bool bOriginalAutomated = CanReimportHandler->IsAutomatedReimport();
                CanReimportHandler->SetAutomatedReimport(bAutomated);
                EReimportResult::Type Result = CanReimportHandler->Reimport(Obj, SourceFileIndex);
                CanReimportHandler->SetAutomatedReimport(bOriginalAutomated);
                if (Result == EReimportResult::Succeeded)
                {
                    Obj->PostEditChange();
                    GEditor->BroadcastObjectReimported(Obj);
                    if (FEngineAnalytics::IsAvailable())
                    {
                        TArray<FAnalyticsEventAttribute> Attributes;
                        Attributes.Add(FAnalyticsEventAttribute(TEXT("ObjectType"), Obj->GetClass()->GetName()));
                        FEngineAnalytics::GetProvider().RecordEvent(TEXT("Editor.Usage.AssetReimported"), Attributes);
                    }
                    bSuccess = true;
                }
                else if (Result == EReimportResult::Cancelled)
                {
                    bShowNotification = false;
                }
            }
        }

        if (bShowNotification)
        {
            // Send a notification of the results
            FText NotificationText;
            if (bSuccess)
            {
                if (bValidSourceFilename)
                {
                    const FString FirstLeafFilename = FPaths::GetCleanFilename(SourceFilenames[0]);

                    if (SourceFilenames.Num() == 1)
                    {
                        FFormatNamedArguments Args;
                        Args.Add(TEXT("ObjectName"), FText::FromString(Obj->GetName()));
                        Args.Add(TEXT("ObjectType"), FText::FromString(Obj->GetClass()->GetName()));
                        Args.Add(TEXT("SourceFile"), FText::FromString(FirstLeafFilename));
                        NotificationText = FText::Format(LOCTEXT("ReimportSuccessfulFrom", "Successfully Reimported: {ObjectName} ({ObjectType}) from file ({SourceFile})"), Args);
                    }
                    else
                    {
                        FFormatNamedArguments Args;
                        Args.Add(TEXT("ObjectName"), FText::FromString(Obj->GetName()));
                        Args.Add(TEXT("ObjectType"), FText::FromString(Obj->GetClass()->GetName()));
                        Args.Add(TEXT("SourceFile"), FText::FromString(FirstLeafFilename));
                        Args.Add(TEXT("Number"), SourceFilenames.Num() - 1);
                        NotificationText = FText::Format(LOCTEXT("ReimportSuccessfulMultiple", "Successfuly Reimported: {ObjectName} ({ObjectType}) from file ({SourceFile}) and {Number} more"), Args);
                    }
                }
                else
                {
                    FFormatNamedArguments Args;
                    Args.Add(TEXT("ObjectName"), FText::FromString(Obj->GetName()));
                    Args.Add(TEXT("ObjectType"), FText::FromString(Obj->GetClass()->GetName()));
                    NotificationText = FText::Format(LOCTEXT("ReimportSuccessful", "Successfully Reimported: {ObjectName} ({ObjectType})"), Args);
                }
            }
            else
            {
                FFormatNamedArguments Args;
                Args.Add(TEXT("ObjectName"), FText::FromString(Obj->GetName()));
                Args.Add(TEXT("ObjectType"), FText::FromString(Obj->GetClass()->GetName()));
                NotificationText = FText::Format(LOCTEXT("ReimportFailed", "Failed to Reimport: {ObjectName} ({ObjectType})"), Args);
            }

            FNotificationInfo Info(NotificationText);
            Info.ExpireDuration                        = 3.0f;
            Info.bUseLargeFont                         = false;
            TSharedPtr<SNotificationItem> Notification = FSlateNotificationManager::Get().AddNotification(Info);
            if (Notification.IsValid())
            {
                Notification->SetCompletionState(bSuccess ? SNotificationItem::CS_Success : SNotificationItem::CS_Fail);
            }
        }
    }

    // Let listeners know whether the reimport was successful or not
    PostReimport.Broadcast(Obj, bSuccess);

    GEditor->RedrawAllViewports();

    return bSuccess;
}

void FReimportManager::ValidateAllSourceFileAndReimport(TArray<UObject*>& ToImportObjects, bool bShowNotification, int32 SourceFileIndex, bool bForceNewFile /*= false*/, bool bAutomated /*= false*/)
{
    // Copy the array to prevent iteration assert if a reimport factory change the selection
    TArray<UObject*> CopyOfSelectedAssets;
    TMap<UObject*, TArray<int32>> MissingFileSelectedAssets;
    for (UObject* Asset: ToImportObjects)
    {
        TArray<FString> SourceFilenames;
        if (this->CanReimport(Asset, &SourceFilenames))
        {
            if (SourceFilenames.Num() == 0)
            {
                TArray<int32>& SourceIndexArray = MissingFileSelectedAssets.FindOrAdd(Asset);
                if (SourceIndexArray.Num() == 0)
                {
                    // Insert an invalid index to indicate no file
                    SourceIndexArray.Add(INDEX_NONE);
                }
            }
            else
            {
                bool bMissingFile = false;

                for (int32 FileIndex = 0; FileIndex < SourceFilenames.Num(); ++FileIndex)
                {
                    FString SourceFilename = SourceFilenames[FileIndex];
                    if (SourceFilename.IsEmpty() || IFileManager::Get().FileSize(*SourceFilename) == INDEX_NONE || (bForceNewFile && (FileIndex == SourceFileIndex || SourceFileIndex == INDEX_NONE)))
                    {
                        TArray<int32>& SourceIndexArray = MissingFileSelectedAssets.FindOrAdd(Asset);
                        SourceIndexArray.Add(FileIndex);
                        bMissingFile = true;
                    }
                }

                if (!bMissingFile)
                {
                    CopyOfSelectedAssets.Add(Asset);
                }
            }
        }
    }

    if (MissingFileSelectedAssets.Num() > 0)
    {
        // Ask the user how to handle missing files before doing the re-import when there is more then one missing file and the "force new file" parameter is false
        // 1. Ask for missing file location for every missing file
        // 2. Ignore missing file asset when doing the re-import
        // 3. Cancel the whole reimport
        EAppReturnType::Type UserChoice = EAppReturnType::Type::Yes;
        if (!bForceNewFile && MissingFileSelectedAssets.Num() > 1)
        {
            // Pop the dialog box asking the question
            FFormatNamedArguments Arguments;
            Arguments.Add(TEXT("MissingNumber"), FText::FromString(FString::FromInt(MissingFileSelectedAssets.Num())));
            int MaxListFile = 100;
            FString AssetToFileListString;
            for (auto Kvp: MissingFileSelectedAssets)
            {
                UObject* Asset                        = Kvp.Key;
                const TArray<int32>& SourceIndexArray = Kvp.Value;
                AssetToFileListString += TEXT("\n");
                if (MaxListFile == 0)
                {
                    AssetToFileListString += TEXT("...");
                    break;
                }
                TArray<FString> SourceFilenames;
                if (this->CanReimport(Asset, &SourceFilenames))
                {
                    MaxListFile--;
                    for (int32 FileIndex: SourceIndexArray)
                    {
                        if (SourceFilenames.IsValidIndex(FileIndex))
                        {
                            AssetToFileListString += FString::Printf(TEXT("Asset %s -> Missing file %s"), *(Asset->GetName()), *(SourceFilenames[FileIndex]));
                        }
                    }
                }
            }
            Arguments.Add(TEXT("AssetToFileList"), FText::FromString(AssetToFileListString));
            FText DialogText  = FText::Format(LOCTEXT("ReimportMissingFileChoiceDialogMessage", "There is {MissingNumber} assets with missing source file path. Do you want to specify a new source file path for each asset?\n \"No\" will skip the reimport of all asset with a missing source file path.\n \"Cancel\" will cancel the whole reimport.\n{AssetToFileList}"), Arguments);
            const FText Title = LOCTEXT("ReimportMissingFileChoiceDialogMessageTitle", "Reimport missing files");

            UserChoice        = FMessageDialog::Open(EAppMsgType::YesNoCancel, DialogText, &Title);
        }

        // Ask missing file locations
        if (UserChoice == EAppReturnType::Type::Yes)
        {
            bool bCancelAll = true;
            // Ask the user for a new source reimport path for each asset
            for (auto Kvp: MissingFileSelectedAssets)
            {
                UObject* Asset                        = Kvp.Key;
                const TArray<int32>& SourceIndexArray = Kvp.Value;
                for (int32 FileIndex: SourceIndexArray)
                {
                    TArray<FString> SourceFilenames;
                    this->GetNewReimportPath(Asset, SourceFilenames, FileIndex);
                    if (!SourceFilenames.IsValidIndex(FileIndex) || SourceFilenames[FileIndex].IsEmpty())
                    {
                        continue;
                    }
                    bCancelAll = false;
                    this->UpdateReimportPath(Asset, SourceFilenames[FileIndex], FileIndex);
                    // We do not want to ask again the user for a file
                    bForceNewFile = false;
                }
                // return if the operation is cancel and we have nothing to re-import
                if (bCancelAll)
                {
                    return;
                }

                CopyOfSelectedAssets.Add(Asset);
            }
        }
        else if (UserChoice == EAppReturnType::Type::Cancel)
        {
            return;
        }
        // If user ignore those asset just not add them to CopyOfSelectedAssets
    }

    FReimportManager::Instance()->ReimportMultiple(CopyOfSelectedAssets, /*bAskForNewFileIfMissing=*/false, bShowNotification, TEXT(""), nullptr, SourceFileIndex, /*bForceNewFile=*/false, bAutomated);
}

void FReimportManager::AddReferencedObjects(FReferenceCollector& Collector)
{
    for (FReimportHandler* Handler: Handlers)
    {
        const UObject* Obj = Handler->GetFactoryObject();
        if (Obj)
        {
            Collector.AddReferencedObject(Obj);
        }
    }
}

void FReimportManager::SortHandlersIfNeeded()
{
    if (bHandlersNeedSorting)
    {
        // Use > operator because we want higher priorities earlier in the list
        Handlers.Sort([](const FReimportHandler& A, const FReimportHandler& B)
                      {
                          return A.GetPriority() > B.GetPriority();
                      });
        bHandlersNeedSorting = false;
    }
}

bool FReimportManager::ReimportMultiple(TArrayView<UObject*> Objects, bool bAskForNewFileIfMissing /*= false*/, bool bShowNotification /*= true*/, FString PreferredReimportFile /*= TEXT("")*/, FReimportHandler* SpecifiedReimportHandler /*= nullptr */, int32 SourceFileIndex /*= INDEX_NONE*/, bool bForceNewFile /*= false*/, bool bAutomated /*= false*/)
{
    bool bBulkSuccess = true;

    FScopedSlowTask BulkReimportTask((float)Objects.Num(), LOCTEXT("BulkReimport_Title", "Reimporting..."));

    for (UObject* CurrentObject: Objects)
    {
        if (CurrentObject)
        {
            FText SingleTaskTest = FText::Format(LOCTEXT("BulkReimport_SingleItem", "Reimporting {0}"), FText::FromString(CurrentObject->GetName()));
            FScopedSlowTask SingleObjectTask(1.0f, SingleTaskTest);
            SingleObjectTask.EnterProgressFrame(1.0f);

            bBulkSuccess = bBulkSuccess && Reimport(CurrentObject, bAskForNewFileIfMissing, bShowNotification, PreferredReimportFile, SpecifiedReimportHandler, SourceFileIndex, bForceNewFile, bAutomated);
        }

        BulkReimportTask.EnterProgressFrame(1.0f);
    }

    // Cleanup the factories after using them
    for (int32 HandlerIndex = 0; HandlerIndex < Handlers.Num(); ++HandlerIndex)
    {
        Handlers[HandlerIndex]->PostImportCleanUp();
    }

    return bBulkSuccess;
}

void FReimportManager::GetNewReimportPath(UObject* Obj, TArray<FString>& InOutFilenames, int32 SourceFileIndex /*= INDEX_NONE*/)
{
    int32 RealSourceFileIndex = SourceFileIndex == INDEX_NONE ? 0 : SourceFileIndex;
    TArray<UObject*> ReturnObjects;
    FString FileTypes;
    FString AllExtensions;
    TArray<UFactory*> Factories;
    TArray<FString> SourceFileLabels;
    FAssetToolsModule& AssetToolsModule = FModuleManager::Get().LoadModuleChecked<FAssetToolsModule>("AssetTools");
    const auto AssetTypeActions         = AssetToolsModule.Get().GetAssetTypeActionsForClass(Obj->GetClass());
    if (AssetTypeActions.IsValid())
    {
        TArray<UObject*> Objects;
        Objects.Add(Obj);
        AssetTypeActions.Pin()->GetSourceFileLabels(Objects, SourceFileLabels);
    }

    // Determine whether we will allow multi select and clear old filenames
    bool bAllowMultiSelect = SourceFileIndex == INDEX_NONE && InOutFilenames.Num() > 1;
    if (bAllowMultiSelect)
    {
        InOutFilenames.Empty();
    }
    else
    {
        if (!InOutFilenames.IsValidIndex(RealSourceFileIndex))
        {
            InOutFilenames.AddZeroed(RealSourceFileIndex - InOutFilenames.Num() + 1);
        }
        InOutFilenames[RealSourceFileIndex].Empty();
    }

    // Get the list of valid factories
    for (TObjectIterator<UClass> It; It; ++It)
    {
        UClass* CurrentClass = (*It);

        if (CurrentClass->IsChildOf(UFactory::StaticClass()) && !(CurrentClass->HasAnyClassFlags(CLASS_Abstract)))
        {
            UFactory* Factory = Cast<UFactory>(CurrentClass->GetDefaultObject());
            if (Factory->bEditorImport && Factory->DoesSupportClass(Obj->GetClass()))
            {
                Factories.Add(Factory);
            }
        }
    }

    if (Factories.Num() <= 0)
    {
        // No matching factories for this asset, fail
        return;
    }

    TMultiMap<uint32, UFactory*> DummyFilterIndexToFactory;

    // Generate the file types and extensions represented by the selected factories
    ObjectTools::GenerateFactoryFileExtensions(Factories, FileTypes, AllExtensions, DummyFilterIndexToFactory);

    FileTypes = FString::Printf(TEXT("All Files (%s)|%s|%s"), *AllExtensions, *AllExtensions, *FileTypes);

    FString DefaultFolder;
    FString DefaultFile;

    TArray<FString> ExistingPaths = Utils::ExtractSourceFilePaths(Obj);
    if (ExistingPaths.Num() > 0)
    {
        DefaultFolder = FPaths::GetPath(ExistingPaths[0]);
        DefaultFile   = FPaths::GetCleanFilename(ExistingPaths[0]);
    }

    // Prompt the user for the filenames
    TArray<FString> OpenFilenames;
    IDesktopPlatform* DesktopPlatform = FDesktopPlatformModule::Get();
    bool bOpened                      = false;
    if (DesktopPlatform)
    {
        void* ParentWindowWindowHandle                   = NULL;

        IMainFrameModule& MainFrameModule                = FModuleManager::LoadModuleChecked<IMainFrameModule>(TEXT("MainFrame"));
        const TSharedPtr<SWindow>& MainFrameParentWindow = MainFrameModule.GetParentWindow();
        if (MainFrameParentWindow.IsValid() && MainFrameParentWindow->GetNativeWindow().IsValid())
        {
            ParentWindowWindowHandle = MainFrameParentWindow->GetNativeWindow()->GetOSWindowHandle();
        }

        FString Title = FString::Printf(TEXT("%s: %s"), *NSLOCTEXT("ReimportManager", "ImportDialogTitle", "Import For").ToString(), *Obj->GetName());
        if (SourceFileIndex != INDEX_NONE)
        {
            if (SourceFileLabels.IsValidIndex(SourceFileIndex))
            {
                Title = FString::Printf(TEXT("%s %s %s: %s"),
                                        *NSLOCTEXT("ReimportManager", "ImportDialogTitleLabelPart1", "Select").ToString(),
                                        *SourceFileLabels[SourceFileIndex],
                                        *NSLOCTEXT("ReimportManager", "ImportDialogTitleLabelPart2", "Source File For").ToString(),
                                        *Obj->GetName());
            }
            else
            {
                FString SourceFileIndexStr = FString::FromInt(SourceFileIndex);
                Title                      = FString::Printf(TEXT("%s %s %s: %s"),
                                                             *NSLOCTEXT("ReimportManager", "ImportDialogTitlePart1", "Select Source File Index").ToString(),
                                                             *SourceFileIndexStr,
                                                             *NSLOCTEXT("ReimportManager", "ImportDialogTitlePart2", "for").ToString(),
                                                             *Obj->GetName());
            }
        }

        bOpened = DesktopPlatform->OpenFileDialog(
            ParentWindowWindowHandle,
            Title,
            *DefaultFolder,
            *DefaultFile,
            FileTypes,
            bAllowMultiSelect ? EFileDialogFlags::Multiple : EFileDialogFlags::None,
            OpenFilenames);
    }

    if (bOpened)
    {
        if (bAllowMultiSelect)
        {
            for (int32 FileIndex = 0; FileIndex < OpenFilenames.Num(); ++FileIndex)
            {
                InOutFilenames.Add(OpenFilenames[FileIndex]);
            }
        }
        else
        {
            // Use the first valid entry
            if (OpenFilenames.Num() > 0)
            {
                InOutFilenames[RealSourceFileIndex] = OpenFilenames[0];
            }
        }
    }
}

FReimportManager::FReimportManager()
{
    // Create reimport handler for textures
    // NOTE: New factories can be created anywhere, inside or outside of editor
    // This is just here for convenience
    UReimportTextureFactory::StaticClass();

    // Create reimport handler for FBX static meshes
    UReimportFbxStaticMeshFactory::StaticClass();

    // Create reimport handler for FBX skeletal meshes
    UReimportFbxSkeletalMeshFactory::StaticClass();

    // Create reimport handler for FBX scene
    UReimportFbxSceneFactory::StaticClass();

    // Create reimport handler for PhysicalMaterialMasks
    UPhysicalMaterialMaskFactory::StaticClass();
}

FReimportManager::~FReimportManager()
{
    Handlers.Empty();
}

int32 FReimportHandler::GetPriority() const
{
    return UFactory::GetDefaultImportPriority();
}

/*-----------------------------------------------------------------------------
        PIE helpers.
-----------------------------------------------------------------------------*/

/**
 * Sets GWorld to the passed in PlayWorld and sets a global flag indicating that we are playing
 * in the Editor.
 *
 * @param	PlayInEditorWorld		PlayWorld
 * @return	the original GWorld
 */
UWorld* SetPlayInEditorWorld(UWorld* PlayInEditorWorld)
{
    check(!GIsPlayInEditorWorld);
    UWorld* SavedWorld   = GWorld;
    GIsPlayInEditorWorld = true;
    GWorld               = PlayInEditorWorld;

    if (FWorldContext* WorldContext = GEngine->GetWorldContextFromWorld(PlayInEditorWorld))
    {
        GPlayInEditorID = WorldContext->PIEInstance;
        UpdatePlayInEditorWorldDebugString(WorldContext);
    }

    return SavedWorld;
}

/**
 * Restores GWorld to the passed in one and reset the global flag indicating whether we are a PIE
 * world or not.
 *
 * @param EditorWorld	original world being edited
 */
void RestoreEditorWorld(UWorld* EditorWorld)
{
    check(GIsPlayInEditorWorld);
    GIsPlayInEditorWorld = false;
    GWorld               = EditorWorld;
    GPlayInEditorID      = INDEX_NONE;
    UpdatePlayInEditorWorldDebugString(nullptr);
}

/**
 * Takes an FName and checks to see that it is unique among all loaded objects.
 *
 * @param	InName		The name to check
 * @param	Outer		The context for validating this object name. Should be a group/package, but could be ANY_PACKAGE if you want to check across the whole system (not recommended)
 * @param	InReason	If the check fails, this string is filled in with the reason why.
 *
 * @return	1 if the name is valid, 0 if it is not
 */

bool IsUniqueObjectName(const FName& InName, UObject* Outer, FText* InReason)
{
    // See if the name is already in use.
    if (StaticFindObject(UObject::StaticClass(), Outer, *InName.ToString()) != NULL)
    {
        if (InReason != NULL)
        {
            *InReason = NSLOCTEXT("UnrealEd", "NameAlreadyInUse", "Name is already in use by another object.");
        }
        return false;
    }

    return true;
}

/**
 * Takes an FName and checks to see that it is unique among all loaded objects.
 *
 * @param	InName		The name to check
 * @param	Outer		The context for validating this object name. Should be a group/package, but could be ANY_PACKAGE if you want to check across the whole system (not recommended)
 * @param	InReason	If the check fails, this string is filled in with the reason why.
 *
 * @return	1 if the name is valid, 0 if it is not
 */

bool IsUniqueObjectName(const FName& InName, UObject* Outer, FText& InReason)
{
    return IsUniqueObjectName(InName, Outer, &InReason);
}

//////////////////////////////////////////////////////////////////////////
// EditorUtilities

namespace EditorUtilities
{
AActor* GetEditorWorldCounterpartActor(AActor* Actor)
{
    const bool bIsSimActor = Actor->GetOutermost()->HasAnyPackageFlags(PKG_PlayInEditor);
    if (bIsSimActor && GEditor && GEditor->PlayWorld != NULL)
    {
        // Do we have a counterpart in the editor world?
        auto* SimWorldActor = Actor;
        if (GEditor->ObjectsThatExistInEditorWorld.Get(SimWorldActor))
        {
            // Find the counterpart level
            UWorld* EditorWorld = GEditor->EditorWorld;
            for (auto LevelIt(EditorWorld->GetLevelIterator()); LevelIt; ++LevelIt)
            {
                auto* Level = *LevelIt;
                if (Level->GetFName() == SimWorldActor->GetLevel()->GetFName())
                {
                    // Find our counterpart actor
                    const bool bExactClass   = false;  // Don't match class exactly, because we support all classes derived from Actor as well!
                    AActor* EditorWorldActor = FindObject<AActor>(Level, *SimWorldActor->GetFName().ToString(), bExactClass);
                    if (EditorWorldActor)
                    {
                        return EditorWorldActor;
                    }
                }
            }
        }
    }

    return NULL;
}

AActor* GetSimWorldCounterpartActor(AActor* Actor)
{
    const bool bIsSimActor = Actor->GetOutermost()->HasAnyPackageFlags(PKG_PlayInEditor);
    if (!bIsSimActor && GEditor && GEditor->EditorWorld != NULL)
    {
        // Do we have a counterpart in the sim world?
        auto* EditorWorldActor = Actor;

        // Find the counterpart level
        UWorld* PlayWorld = GEditor->PlayWorld;
        if (PlayWorld != nullptr)
        {
            for (auto LevelIt(PlayWorld->GetLevelIterator()); LevelIt; ++LevelIt)
            {
                auto* Level = *LevelIt;
                if (Level->GetFName() == EditorWorldActor->GetLevel()->GetFName())
                {
                    // Find our counterpart actor
                    const bool bExactClass = false;  // Don't match class exactly, because we support all classes derived from Actor as well!
                    AActor* SimWorldActor  = FindObject<AActor>(Level, *EditorWorldActor->GetFName().ToString(), bExactClass);
                    if (SimWorldActor && GEditor->ObjectsThatExistInEditorWorld.Get(SimWorldActor))
                    {
                        return SimWorldActor;
                    }
                }
            }
        }
    }

    return NULL;
}

// Searches through the target components array of the target actor for the source component
// TargetComponents array is passed in populated to avoid repeated refetching and StartIndex
// is updated as an optimization based on the assumption that the standard use case is iterating
// over two component arrays that will be parallel in order
template <class AllocatorType = FDefaultAllocator>
UActorComponent* FindMatchingComponentInstance(UActorComponent* SourceComponent, AActor* TargetActor, const TArray<UActorComponent*, AllocatorType>& TargetComponents, int32& StartIndex)
{
    UActorComponent* TargetComponent = StartIndex < TargetComponents.Num() ? TargetComponents[StartIndex] : nullptr;

    // If the source and target components do not match (e.g. context-specific), attempt to find a match in the target's array elsewhere
    if ((SourceComponent != nullptr) && ((TargetComponent == nullptr) || (SourceComponent->GetClass() != TargetComponent->GetClass()) || (SourceComponent->GetFName() != TargetComponent->GetFName())))
    {
        const bool bSourceIsArchetype = SourceComponent->HasAnyFlags(RF_ArchetypeObject);
        // Reset the target component since it doesn't match the source
        TargetComponent                 = nullptr;

        const int32 NumTargetComponents = TargetComponents.Num();
        if (NumTargetComponents > 0)
        {
            // Attempt to locate a match elsewhere in the target's component list
            const int32 StartingIndex      = (bSourceIsArchetype ? StartIndex : StartIndex + 1);
            int32 FindTargetComponentIndex = (StartingIndex >= NumTargetComponents) ? 0 : StartingIndex;
            do
            {
                UActorComponent* FindTargetComponent = TargetComponents[FindTargetComponentIndex];

                if (FindTargetComponent->GetClass() == SourceComponent->GetClass())
                {
                    // In the case that the SourceComponent is an Archetype there is a better than even chance the name won't match due to the way the SCS
                    // is set up, so we're actually going to reverse search the archetype chain
                    if (bSourceIsArchetype)
                    {
                        UActorComponent* CheckComponent = FindTargetComponent;
                        while (CheckComponent)
                        {
                            if (SourceComponent == CheckComponent->GetArchetype())
                            {
                                TargetComponent = FindTargetComponent;
                                StartIndex      = FindTargetComponentIndex;
                                break;
                            }
                            CheckComponent = Cast<UActorComponent>(CheckComponent->GetArchetype());
                        }
                        if (TargetComponent)
                        {
                            break;
                        }
                    }
                    else
                    {
                        // If we found a match, update the target component and adjust the target index to the matching position
                        if (FindTargetComponent != NULL && SourceComponent->GetFName() == FindTargetComponent->GetFName())
                        {
                            TargetComponent = FindTargetComponent;
                            StartIndex      = FindTargetComponentIndex;
                            break;
                        }
                    }
                }

                // Increment the index counter, and loop back to 0 if necessary
                if (++FindTargetComponentIndex >= NumTargetComponents)
                {
                    FindTargetComponentIndex = 0;
                }

            } while (FindTargetComponentIndex != StartIndex);
        }

        // If we still haven't found a match and we're targeting a class default object what we're really looking
        // for is an Archetype
        if (TargetComponent == nullptr && TargetActor->HasAnyFlags(RF_ClassDefaultObject | RF_ArchetypeObject))
        {
            if (bSourceIsArchetype)
            {
                UBlueprintGeneratedClass* BPGC = Cast<UBlueprintGeneratedClass>(SourceComponent->GetOuter());

                // If the target actor's class is a child of our owner and we're both archetypes, then we're actually looking for an overridden version of ourselves
                if (BPGC && TargetActor->GetClass()->IsChildOf(BPGC))
                {
                    TargetComponent = Cast<UActorComponent>(TargetActor->GetClass()->FindArchetype(SourceComponent->GetClass(), SourceComponent->GetFName()));

                    // If it is us, then we're done, we don't need to find this
                    if (TargetComponent == SourceComponent)
                    {
                        TargetComponent = nullptr;
                    }
                }
            }
            else
            {
                TargetComponent = CastChecked<UActorComponent>(SourceComponent->GetArchetype(), ECastCheckedType::NullAllowed);

                // If the returned target component is not from the direct class of the actor we're targeting, we need to insert an inheritable component
                if (TargetComponent && (TargetComponent->GetOuter() != TargetActor->GetClass()))
                {
                    // This component doesn't exist in the hierarchy anywhere and we're not going to modify the CDO, so we'll drop it
                    if (TargetComponent->HasAnyFlags(RF_ClassDefaultObject))
                    {
                        TargetComponent = nullptr;
                    }
                    else
                    {
                        UBlueprintGeneratedClass* BPGC                            = CastChecked<UBlueprintGeneratedClass>(TargetActor->GetClass());
                        UBlueprint* Blueprint                                     = CastChecked<UBlueprint>(BPGC->ClassGeneratedBy);
                        UInheritableComponentHandler* InheritableComponentHandler = Blueprint->GetInheritableComponentHandler(true);
                        if (InheritableComponentHandler)
                        {
                            FComponentKey Key;
                            FName const SourceComponentName = SourceComponent->GetFName();

                            BPGC                            = Cast<UBlueprintGeneratedClass>(BPGC->GetSuperClass());
                            while (!Key.IsValid() && BPGC)
                            {
                                USCS_Node* SCSNode = BPGC->SimpleConstructionScript->FindSCSNode(SourceComponentName);
                                if (!SCSNode)
                                {
                                    UBlueprint* SuperBlueprint = CastChecked<UBlueprint>(BPGC->ClassGeneratedBy);
                                    for (UActorComponent* ComponentTemplate: BPGC->ComponentTemplates)
                                    {
                                        if (ComponentTemplate->GetFName() == SourceComponentName)
                                        {
                                            if (UEdGraph* UCSGraph = FBlueprintEditorUtils::FindUserConstructionScript(SuperBlueprint))
                                            {
                                                TArray<UK2Node_AddComponent*> ComponentNodes;
                                                UCSGraph->GetNodesOfClass<UK2Node_AddComponent>(ComponentNodes);

                                                for (UK2Node_AddComponent* UCSNode: ComponentNodes)
                                                {
                                                    if (ComponentTemplate == UCSNode->GetTemplateFromNode())
                                                    {
                                                        Key = FComponentKey(SuperBlueprint, FUCSComponentId(UCSNode));
                                                        break;
                                                    }
                                                }
                                            }
                                            break;
                                        }
                                    }
                                }
                                else
                                {
                                    Key = FComponentKey(SCSNode);
                                    break;
                                }
                                BPGC = Cast<UBlueprintGeneratedClass>(BPGC->GetSuperClass());
                            }

                            if (ensure(Key.IsValid()))
                            {
                                check(InheritableComponentHandler->GetOverridenComponentTemplate(Key) == nullptr);
                                TargetComponent = InheritableComponentHandler->CreateOverridenComponentTemplate(Key);
                            }
                            else
                            {
                                TargetComponent = nullptr;
                            }
                        }
                    }
                }
            }
        }
    }

    return TargetComponent;
}

UActorComponent* FindMatchingComponentInstance(UActorComponent* SourceComponent, AActor* TargetActor)
{
    UActorComponent* MatchingComponent = NULL;
    int32 StartIndex                   = 0;

    if (TargetActor)
    {
        TInlineComponentArray<UActorComponent*> TargetComponents;
        TargetActor->GetComponents(TargetComponents);
        MatchingComponent = FindMatchingComponentInstance(SourceComponent, TargetActor, TargetComponents, StartIndex);
    }

    return MatchingComponent;
}

void CopySinglePropertyRecursive(const void* const InSourcePtr, void* const InTargetPtr, UObject* const InTargetObject, FProperty* const InProperty)
{
    // Properties that are *object* properties are tricky
    // Sometimes the object will be a reference to a PIE-world object, and copying that reference back to an actor CDO asset is not a good idea
    // If the property is referencing an actor or actor component in the PIE world, then we can try and fix that reference up to the equivalent
    // from the editor world; otherwise we have to skip it
    bool bNeedsGenericCopy = true;
    if (FObjectPropertyBase* const ObjectProperty = CastField<FObjectPropertyBase>(InProperty))
    {
        const int32 PropertyArrayDim = InProperty->ArrayDim;
        for (int32 ArrayIndex = 0; ArrayIndex < PropertyArrayDim; ArrayIndex++)
        {
            UObject* const SourceObjectPropertyValue = ObjectProperty->GetObjectPropertyValue_InContainer(InSourcePtr, ArrayIndex);
            if (SourceObjectPropertyValue && SourceObjectPropertyValue->GetOutermost()->HasAnyPackageFlags(PKG_PlayInEditor))
            {
                // Not all the code paths below actually copy the object, but even if they don't we need to claim that they
                // did, as copying a reference to an object in a PIE world leads to crashes
                bNeedsGenericCopy = false;

                // REFERENCE an existing actor in the editor world from a REFERENCE in the PIE world
                if (SourceObjectPropertyValue->IsA(AActor::StaticClass()))
                {
                    // We can try and fix-up an actor reference from the PIE world to instead be the version from the persistent world
                    AActor* const EditorWorldActor = GetEditorWorldCounterpartActor(Cast<AActor>(SourceObjectPropertyValue));
                    if (EditorWorldActor)
                    {
                        ObjectProperty->SetObjectPropertyValue_InContainer(InTargetPtr, EditorWorldActor, ArrayIndex);
                    }
                }
                // REFERENCE an existing actor component in the editor world from a REFERENCE in the PIE world
                else if (SourceObjectPropertyValue->IsA(UActorComponent::StaticClass()) && InTargetObject->IsA(AActor::StaticClass()))
                {
                    AActor* const TargetActor = Cast<AActor>(InTargetObject);
                    TInlineComponentArray<UActorComponent*> TargetComponents;
                    TargetActor->GetComponents(TargetComponents);

                    // We can try and fix-up an actor component reference from the PIE world to instead be the version from the persistent world
                    int32 TargetComponentIndex                  = 0;
                    UActorComponent* const EditorWorldComponent = FindMatchingComponentInstance(Cast<UActorComponent>(SourceObjectPropertyValue), TargetActor, TargetComponents, TargetComponentIndex);
                    if (EditorWorldComponent)
                    {
                        ObjectProperty->SetObjectPropertyValue_InContainer(InTargetPtr, EditorWorldComponent, ArrayIndex);
                    }
                }
            }
        }
    }
    else if (FStructProperty* const StructProperty = CastField<FStructProperty>(InProperty))
    {
        // Ensure that the target struct is initialized before copying fields from the source.
        StructProperty->InitializeValue_InContainer(InTargetPtr);

        const int32 PropertyArrayDim = InProperty->ArrayDim;
        for (int32 ArrayIndex = 0; ArrayIndex < PropertyArrayDim; ArrayIndex++)
        {
            const void* const SourcePtr = StructProperty->ContainerPtrToValuePtr<void>(InSourcePtr, ArrayIndex);
            void* const TargetPtr       = StructProperty->ContainerPtrToValuePtr<void>(InTargetPtr, ArrayIndex);

            for (TFieldIterator<FProperty> It(StructProperty->Struct); It; ++It)
            {
                FProperty* const InnerProperty = *It;
                CopySinglePropertyRecursive(SourcePtr, TargetPtr, InTargetObject, InnerProperty);
            }
        }

        bNeedsGenericCopy = false;
    }
    else if (FArrayProperty* const ArrayProperty = CastField<FArrayProperty>(InProperty))
    {
        check(InProperty->ArrayDim == 1);
        FScriptArrayHelper SourceArrayHelper(ArrayProperty, ArrayProperty->ContainerPtrToValuePtr<void>(InSourcePtr));
        FScriptArrayHelper TargetArrayHelper(ArrayProperty, ArrayProperty->ContainerPtrToValuePtr<void>(InTargetPtr));

        FProperty* InnerProperty = ArrayProperty->Inner;
        int32 Num                = SourceArrayHelper.Num();

        // here we emulate FArrayProperty::CopyValuesInternal()
        if (!(InnerProperty->PropertyFlags & CPF_IsPlainOldData))
        {
            TargetArrayHelper.EmptyAndAddValues(Num);
        }
        else
        {
            TargetArrayHelper.EmptyAndAddUninitializedValues(Num);
        }

        for (int32 Index = 0; Index < Num; Index++)
        {
            CopySinglePropertyRecursive(SourceArrayHelper.GetRawPtr(Index), TargetArrayHelper.GetRawPtr(Index), InTargetObject, InnerProperty);
        }

        bNeedsGenericCopy = false;
    }

    // Handle copying properties that either aren't an object, or aren't part of the PIE world
    if (bNeedsGenericCopy)
    {
        InProperty->CopyCompleteValue_InContainer(InTargetPtr, InSourcePtr);
    }
}

void CopySingleProperty(const UObject* const InSourceObject, UObject* const InTargetObject, FProperty* const InProperty)
{
    CopySinglePropertyRecursive(InSourceObject, InTargetObject, InTargetObject, InProperty);
}

int32 CopyActorProperties(AActor* SourceActor, AActor* TargetActor, const FCopyOptions& Options)
{
    check(SourceActor != nullptr && TargetActor != nullptr);

    const bool bIsPreviewing  = (Options.Flags & ECopyOptions::PreviewOnly) != 0;

    int32 CopiedPropertyCount = 0;

    // The actor's classes should be compatible, right?
    UClass* ActorClass = SourceActor->GetClass();
    check(TargetActor->GetClass()->IsChildOf(ActorClass));

    // Get archetype instances for propagation (if requested)
    TArray<AActor*> ArchetypeInstances;
    if (Options.Flags & ECopyOptions::PropagateChangesToArchetypeInstances)
    {
        TArray<UObject*> ObjectArchetypeInstances;
        TargetActor->GetArchetypeInstances(ObjectArchetypeInstances);

        for (UObject* ObjectArchetype: ObjectArchetypeInstances)
        {
            if (AActor* ActorArchetype = Cast<AActor>(ObjectArchetype))
            {
                ArchetypeInstances.Add(ActorArchetype);
            }
        }
    }

    bool bTransformChanged = false;

    // Copy non-component properties from the old actor to the new actor
    // @todo sequencer: Most of this block of code was borrowed (pasted) from UEditorEngine::ConvertActors().  If we end up being able to share these code bodies, that would be nice!
    TSet<UObject*> ModifiedObjects;
    for (FProperty* Property = ActorClass->PropertyLink; Property != nullptr; Property = Property->PropertyLinkNext)
    {
        const bool bIsTransient          = !!(Property->PropertyFlags & CPF_Transient);
        const bool bIsComponentContainer = !!(Property->PropertyFlags & CPF_ContainsInstancedReference);
        const bool bIsComponentProp      = !!(Property->PropertyFlags & (CPF_InstancedReference | CPF_ContainsInstancedReference));
        const bool bIsBlueprintReadonly  = !!(Options.Flags & ECopyOptions::FilterBlueprintReadOnly) && !!(Property->PropertyFlags & CPF_BlueprintReadOnly);
        const bool bIsIdentical          = Property->Identical_InContainer(SourceActor, TargetActor);

        if (!bIsTransient && !bIsIdentical && !bIsComponentContainer && !bIsComponentProp && !bIsBlueprintReadonly)
        {
            const bool bIsSafeToCopy = (!(Options.Flags & ECopyOptions::OnlyCopyEditOrInterpProperties) || (Property->HasAnyPropertyFlags(CPF_Edit | CPF_Interp))) && (!(Options.Flags & ECopyOptions::SkipInstanceOnlyProperties) || (!Property->HasAllPropertyFlags(CPF_DisableEditOnTemplate)));
            if (bIsSafeToCopy)
            {
                if (!Options.CanCopyProperty(*Property, *SourceActor))
                {
                    continue;
                }

                if (!bIsPreviewing)
                {
                    if (!ModifiedObjects.Contains(TargetActor))
                    {
                        // Start modifying the target object
                        TargetActor->Modify();
                        ModifiedObjects.Add(TargetActor);
                    }

                    if (Options.Flags & ECopyOptions::CallPostEditChangeProperty)
                    {
                        TargetActor->PreEditChange(Property);
                    }

                    // Determine which archetype instances match the current property value of the target actor (before it gets changed). We only want to propagate the change to those instances.
                    TArray<UObject*> ArchetypeInstancesToChange;
                    if (Options.Flags & ECopyOptions::PropagateChangesToArchetypeInstances)
                    {
                        for (AActor* ArchetypeInstance: ArchetypeInstances)
                        {
                            if (ArchetypeInstance != nullptr && Property->Identical_InContainer(ArchetypeInstance, TargetActor))
                            {
                                ArchetypeInstancesToChange.Add(ArchetypeInstance);
                            }
                        }
                    }

                    CopySingleProperty(SourceActor, TargetActor, Property);

                    if (Options.Flags & ECopyOptions::CallPostEditChangeProperty)
                    {
                        FPropertyChangedEvent PropertyChangedEvent(Property);
                        TargetActor->PostEditChangeProperty(PropertyChangedEvent);
                    }

                    if (Options.Flags & ECopyOptions::PropagateChangesToArchetypeInstances)
                    {
                        for (int32 InstanceIndex = 0; InstanceIndex < ArchetypeInstancesToChange.Num(); ++InstanceIndex)
                        {
                            UObject* ArchetypeInstance = ArchetypeInstancesToChange[InstanceIndex];
                            if (ArchetypeInstance != nullptr)
                            {
                                if (!ModifiedObjects.Contains(ArchetypeInstance))
                                {
                                    ArchetypeInstance->Modify();
                                    ModifiedObjects.Add(ArchetypeInstance);
                                }

                                CopySingleProperty(TargetActor, ArchetypeInstance, Property);
                            }
                        }
                    }
                }

                ++CopiedPropertyCount;
            }
        }
    }

    // Copy component properties from source to target if they match. Note that the component lists may not be 1-1 due to context-specific components (e.g. editor-only sprites, etc.).

    TArray<TPair<UActorComponent*, UActorComponent*>> SourceTargetComponentPairs;

    auto BuildComponentPairs = [&SourceTargetComponentPairs, SourceActor](AActor* PrimaryActor, AActor* SecondaryActor)
    {
        TInlineComponentArray<UActorComponent*> SecondaryComponents(SecondaryActor);

        const bool bPrimaryIsSource   = (PrimaryActor == SourceActor);
        int32 SecondaryComponentIndex = 0;
        for (UActorComponent* PrimaryComponent: PrimaryActor->GetComponents())
        {
            if (PrimaryComponent->CreationMethod == EComponentCreationMethod::UserConstructionScript)
            {
                continue;
            }
            if (UActorComponent* SecondaryComponent = FindMatchingComponentInstance(PrimaryComponent, SecondaryActor, SecondaryComponents, SecondaryComponentIndex))
            {
                if (bPrimaryIsSource)
                {
                    SourceTargetComponentPairs.Emplace(PrimaryComponent, SecondaryComponent);
                }
                else
                {
                    SourceTargetComponentPairs.Emplace(SecondaryComponent, PrimaryComponent);
                }
            }
        }
    };

    const bool bSourceActorIsCDO   = SourceActor->HasAnyFlags(RF_ClassDefaultObject | RF_ArchetypeObject);
    const bool bTargetActorIsCDO   = TargetActor->HasAnyFlags(RF_ClassDefaultObject | RF_ArchetypeObject);
    const bool bSourceActorIsBPCDO = bSourceActorIsCDO && ActorClass->HasAllClassFlags(CLASS_CompiledFromBlueprint);

    // If the source actor is a CDO, then the target actor should drive the collection of components since FindMatchingComponentInstance
    // does work to seek out SCS and ICH components for blueprints
    if (bSourceActorIsCDO)
    {
        BuildComponentPairs(TargetActor, SourceActor);
    }
    else
    {
        BuildComponentPairs(SourceActor, TargetActor);
    }

    for (const TPair<UActorComponent*, UActorComponent*>& ComponentPair: SourceTargetComponentPairs)
    {
        UActorComponent* SourceComponent = ComponentPair.Key;
        UActorComponent* TargetComponent = ComponentPair.Value;

        UClass* ComponentClass           = SourceComponent->GetClass();
        check(ComponentClass == TargetComponent->GetClass());

        // Build a list of matching component archetype instances for propagation (if requested)
        TArray<UActorComponent*> ComponentArchetypeInstances;
        if (Options.Flags & ECopyOptions::PropagateChangesToArchetypeInstances)
        {
            for (AActor* ArchetypeInstance: ArchetypeInstances)
            {
                if (ArchetypeInstance != nullptr)
                {
                    UActorComponent* ComponentArchetypeInstance = FindMatchingComponentInstance(TargetComponent, ArchetypeInstance);
                    if (ComponentArchetypeInstance != nullptr)
                    {
                        ComponentArchetypeInstances.AddUnique(ComponentArchetypeInstance);
                    }
                }
            }
        }

        TSet<const FProperty*> SourceUCSModifiedProperties;
        SourceComponent->GetUCSModifiedProperties(SourceUCSModifiedProperties);

        TArray<UActorComponent*> ComponentInstancesToReregister;

        // Copy component properties
        for (FProperty* Property = ComponentClass->PropertyLink; Property != nullptr; Property = Property->PropertyLinkNext)
        {
            const bool bIsTransient = !!(Property->PropertyFlags & CPF_Transient);
            const bool bIsIdentical = Property->Identical_InContainer(SourceComponent, TargetComponent);
            const bool bIsComponent = !!(Property->PropertyFlags & (CPF_InstancedReference | CPF_ContainsInstancedReference));
            const bool bIsTransform =
                Property->GetFName() == USceneComponent::GetRelativeScale3DPropertyName() ||
                Property->GetFName() == USceneComponent::GetRelativeLocationPropertyName() ||
                Property->GetFName() == USceneComponent::GetRelativeRotationPropertyName();

            auto SourceComponentIsRoot = [&]()
            {
                USceneComponent* RootComponent = SourceActor->GetRootComponent();
                if (SourceComponent == RootComponent)
                {
                    return true;
                }
                else if (RootComponent == nullptr && bSourceActorIsBPCDO)
                {
                    // If we're dealing with a BP CDO as source, then look at the target for whether this is the root component
                    return (TargetComponent == TargetActor->GetRootComponent());
                }
                return false;
            };

            if (!bIsTransient && !bIsIdentical && !bIsComponent && !SourceUCSModifiedProperties.Contains(Property) && (!bIsTransform || (!bSourceActorIsCDO && !bTargetActorIsCDO) || !SourceComponentIsRoot()))
            {
                const bool bIsSafeToCopy = (!(Options.Flags & ECopyOptions::OnlyCopyEditOrInterpProperties) || (Property->HasAnyPropertyFlags(CPF_Edit | CPF_Interp))) && (!(Options.Flags & ECopyOptions::SkipInstanceOnlyProperties) || (!Property->HasAllPropertyFlags(CPF_DisableEditOnTemplate)));
                if (bIsSafeToCopy)
                {
                    if (!Options.CanCopyProperty(*Property, *SourceActor))
                    {
                        continue;
                    }

                    if (!bIsPreviewing)
                    {
                        if (!ModifiedObjects.Contains(TargetComponent))
                        {
                            TargetComponent->UnregisterComponent();
                            TargetComponent->SetFlags(RF_Transactional);
                            TargetComponent->Modify();
                            ModifiedObjects.Add(TargetComponent);
                        }

                        if (Options.Flags & ECopyOptions::CallPostEditChangeProperty)
                        {
                            // @todo simulate: Should we be calling this on the component instead?
                            TargetActor->PreEditChange(Property);
                        }

                        // Determine which component archetype instances match the current property value of the target component (before it gets changed). We only want to propagate the change to those instances.
                        TArray<UActorComponent*> ComponentArchetypeInstancesToChange;
                        if (Options.Flags & ECopyOptions::PropagateChangesToArchetypeInstances)
                        {
                            for (UActorComponent* ComponentArchetypeInstance: ComponentArchetypeInstances)
                            {
                                if (ComponentArchetypeInstance != nullptr && Property->Identical_InContainer(ComponentArchetypeInstance, TargetComponent))
                                {
                                    bool bAdd = true;
                                    // We also need to double check that either the direct archetype of the target is also identical
                                    if (ComponentArchetypeInstance->GetArchetype() != TargetComponent)
                                    {
                                        UClass* TargetCompClass         = TargetComponent->GetClass();
                                        UActorComponent* CheckComponent = CastChecked<UActorComponent>(ComponentArchetypeInstance->GetArchetype());
                                        while (CheckComponent != ComponentArchetypeInstance && CheckComponent->GetClass() == TargetCompClass)
                                        {
                                            if (!Property->Identical_InContainer(CheckComponent, TargetComponent))
                                            {
                                                bAdd = false;
                                                break;
                                            }
                                            CheckComponent = CastChecked<UActorComponent>(CheckComponent->GetArchetype());
                                        }
                                    }

                                    if (bAdd)
                                    {
                                        ComponentArchetypeInstancesToChange.Add(ComponentArchetypeInstance);
                                    }
                                }
                            }
                        }

                        CopySingleProperty(SourceComponent, TargetComponent, Property);

                        if (Options.Flags & ECopyOptions::CallPostEditChangeProperty)
                        {
                            FPropertyChangedEvent PropertyChangedEvent(Property);
                            TargetActor->PostEditChangeProperty(PropertyChangedEvent);
                        }

                        if (Options.Flags & ECopyOptions::PropagateChangesToArchetypeInstances)
                        {
                            for (int32 InstanceIndex = 0; InstanceIndex < ComponentArchetypeInstancesToChange.Num(); ++InstanceIndex)
                            {
                                UActorComponent* ComponentArchetypeInstance = ComponentArchetypeInstancesToChange[InstanceIndex];
                                if (ComponentArchetypeInstance != nullptr)
                                {
                                    if (!ModifiedObjects.Contains(ComponentArchetypeInstance))
                                    {
                                        // Ensure that this instance will be included in any undo/redo operations, and record it into the transaction buffer.
                                        // Note: We don't do this for components that originate from script, because they will be re-instanced from the template after an undo, so there is no need to record them.
                                        if (!ComponentArchetypeInstance->IsCreatedByConstructionScript())
                                        {
                                            ComponentArchetypeInstance->SetFlags(RF_Transactional);
                                            ComponentArchetypeInstance->Modify();
                                            ModifiedObjects.Add(ComponentArchetypeInstance);
                                        }

                                        // We must also modify the owner, because we'll need script components to be reconstructed as part of an undo operation.
                                        AActor* Owner = ComponentArchetypeInstance->GetOwner();
                                        if (Owner != nullptr && !ModifiedObjects.Contains(Owner))
                                        {
                                            Owner->Modify();
                                            ModifiedObjects.Add(Owner);
                                        }
                                    }

                                    if (ComponentArchetypeInstance->IsRegistered())
                                    {
                                        ComponentArchetypeInstance->UnregisterComponent();
                                        ComponentInstancesToReregister.Add(ComponentArchetypeInstance);
                                    }

                                    CopySingleProperty(TargetComponent, ComponentArchetypeInstance, Property);
                                }
                            }
                        }
                    }

                    ++CopiedPropertyCount;

                    if (bIsTransform)
                    {
                        bTransformChanged = true;
                    }
                }
            }
        }

        for (UActorComponent* ModifiedComponentInstance: ComponentInstancesToReregister)
        {
            ModifiedComponentInstance->RegisterComponent();
        }
    }

    if (!bIsPreviewing && CopiedPropertyCount > 0 && TargetActor->GetClass()->HasAllClassFlags(CLASS_CompiledFromBlueprint))
    {
        if (bTargetActorIsCDO)
        {
            FBlueprintEditorUtils::PostEditChangeBlueprintActors(CastChecked<UBlueprint>(TargetActor->GetClass()->ClassGeneratedBy));
        }
        else
        {
            TargetActor->RerunConstructionScripts();
        }
    }

    // If one of the changed properties was part of the actor's transformation, then we'll call PostEditMove too.
    if (!bIsPreviewing && bTransformChanged)
    {
        if (Options.Flags & ECopyOptions::CallPostEditMove)
        {
            const bool bFinishedMove = true;
            TargetActor->PostEditMove(bFinishedMove);
        }
    }

    return CopiedPropertyCount;
}
}  // namespace EditorUtilities

//////////////////////////////////////////////////////////////////////////
// FCachedActorLabels

FCachedActorLabels::FCachedActorLabels()
{
}

FCachedActorLabels::FCachedActorLabels(UWorld* World, const TSet<AActor*>& IgnoredActors)
{
    Populate(World, IgnoredActors);
}

void FCachedActorLabels::Populate(UWorld* World, const TSet<AActor*>& IgnoredActors)
{
    ActorLabels.Empty();

    for (FActorIterator It(World); It; ++It)
    {
        if (!IgnoredActors.Contains(*It))
        {
            ActorLabels.Add(It->GetActorLabel());
        }
    }
    ActorLabels.Shrink();
}

//////////////////////////////////////////////////////////////////////////

void ExecuteInvalidateCachedShaders(const TArray<FString>& Args)
{
    if (Args.Num() == 0)
    {
        // todo: log error, at least one command is needed
        UE_LOG(LogConsoleResponse, Display, TEXT("r.InvalidateCachedShaders failed\nAs this command should not be executed accidentally it requires you to specify an extra parameter."));
        return;
    }

    FString FileName                              = FPaths::EngineDir() + TEXT("Shaders/Public/ShaderVersion.ush");

    FileName                                      = IFileManager::Get().ConvertToAbsolutePathForExternalAppForRead(*FileName);

    ISourceControlProvider& SourceControlProvider = ISourceControlModule::Get().GetProvider();
    SourceControlProvider.Init();

    FSourceControlStatePtr SourceControlState = SourceControlProvider.GetState(FileName, EStateCacheUsage::ForceUpdate);
    if (SourceControlState.IsValid())
    {
        if (SourceControlState->CanCheckout() || SourceControlState->IsCheckedOutOther())
        {
            if (SourceControlProvider.Execute(ISourceControlOperation::Create<FCheckOut>(), FileName) == ECommandResult::Failed)
            {
                UE_LOG(LogConsoleResponse, Display, TEXT("r.InvalidateCachedShaders failed\nCouldn't check out \"ShaderVersion.ush\""));
                return;
            }
        }
        else if (!SourceControlState->IsSourceControlled())
        {
            UE_LOG(LogConsoleResponse, Display, TEXT("r.InvalidateCachedShaders failed\n\"ShaderVersion.ush\" is not under source control."));
        }
        else if (SourceControlState->IsCheckedOutOther())
        {
            UE_LOG(LogConsoleResponse, Display, TEXT("r.InvalidateCachedShaders failed\n\"ShaderVersion.ush\" is already checked out by someone else\n(UE4 SourceControl needs to be fixed to allow multiple checkout.)"));
            return;
        }
        else if (SourceControlState->IsDeleted())
        {
            UE_LOG(LogConsoleResponse, Display, TEXT("r.InvalidateCachedShaders failed\n\"ShaderVersion.ush\" is marked for delete"));
            return;
        }
    }

    IPlatformFile& PlatformFile = FPlatformFileManager::Get().GetPlatformFile();

    IFileHandle* FileHandle     = PlatformFile.OpenWrite(*FileName);
    if (FileHandle)
    {
        FString Guid = FString(
                           TEXT("// This file is automatically generated by the console command r.InvalidateCachedShaders\n")
                               TEXT("// Each time the console command is executed it generates a new GUID. As this file is included\n")
                                   TEXT("// in Platform.ush (which should be included in any shader) it allows to invalidate the shader DDC.\n")
                                       TEXT("// \n")
                                           TEXT("// GUID = ")) +
                       FGuid::NewGuid().ToString();

        FileHandle->Write((const uint8*)TCHAR_TO_ANSI(*Guid), Guid.Len());
        delete FileHandle;

        UE_LOG(LogConsoleResponse, Display, TEXT("r.InvalidateCachedShaders succeeded\n\"ShaderVersion.ush\" was updated.\n"));
    }
    else
    {
        UE_LOG(LogConsoleResponse, Display, TEXT("r.InvalidateCachedShaders failed\nCouldn't open \"ShaderVersion.ush\".\n"));
    }
}

FAutoConsoleCommand InvalidateCachedShaders(
    TEXT("r.InvalidateCachedShaders"),
    TEXT("Invalidate shader cache by making a unique change to ShaderVersion.ush which is included in common.usf.")
        TEXT("To initiate actual the recompile of all shaders use \"recompileshaders changed\" or press \"Ctrl Shift .\".\n")
            TEXT("The ShaderVersion.ush file should be automatically checked out but  it needs to be checked in to have effect on other machines."),
    FConsoleCommandWithArgsDelegate::CreateStatic(ExecuteInvalidateCachedShaders));

//////////////////////////////////////////////////////////////////////////

#undef LOCTEXT_NAMESPACE