EM_Task/CoreUObject/Private/UObject/PropertyByte.cpp

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

#include "CoreMinimal.h"
#include "UObject/ObjectMacros.h"
#include "UObject/Class.h"
#include "UObject/PropertyPortFlags.h"
#include "UObject/UnrealType.h"
#include "UObject/UnrealTypePrivate.h"
#include "UObject/UObjectThreadContext.h"
#include "Serialization/ArchiveUObjectFromStructuredArchive.h"
#include "Algo/Find.h"
#include "UObject/LinkerLoad.h"
#include "Misc/NetworkVersion.h"

// WARNING: This should always be the last include in any file that needs it (except .generated.h)
#include "UObject/UndefineUPropertyMacros.h"

/*-----------------------------------------------------------------------------
        FByteProperty.
-----------------------------------------------------------------------------*/

IMPLEMENT_FIELD(FByteProperty)

#if WITH_EDITORONLY_DATA
FByteProperty::FByteProperty(UField* InField)
    : TProperty_Numeric(InField)
{
    UByteProperty* SourceProperty = CastChecked<UByteProperty>(InField);
    Enum                          = SourceProperty->Enum;
}
#endif  // WITH_EDITORONLY_DATA

void FByteProperty::GetPreloadDependencies(TArray<UObject*>& OutDeps)
{
    Super::GetPreloadDependencies(OutDeps);
    OutDeps.Add(Enum);
}

void FByteProperty::SerializeItem(FStructuredArchive::FSlot Slot, void* Value, void const* Defaults) const
{
    FArchive& UnderlyingArchive = Slot.GetUnderlyingArchive();

    if (Enum && UnderlyingArchive.UseToResolveEnumerators())
    {
        Slot.EnterStream();
        const int64 ResolvedIndex = Enum->ResolveEnumerator(UnderlyingArchive, *(uint8*)Value);
        *(uint8*)Value            = static_cast<uint8>(ResolvedIndex);
        return;
    }

    // Serialize enum values by name unless we're not saving or loading OR for backwards compatibility
    const bool bUseBinarySerialization = (Enum == NULL) || (!UnderlyingArchive.IsLoading() && !UnderlyingArchive.IsSaving());
    if (bUseBinarySerialization)
    {
        Super::SerializeItem(Slot, Value, Defaults);
    }
    // Loading
    else if (UnderlyingArchive.IsLoading())
    {
        FName EnumValueName;
        Slot << EnumValueName;
        // Make sure enum is properly populated
        if (Enum->HasAnyFlags(RF_NeedLoad))
        {
            UnderlyingArchive.Preload(Enum);
        }

        // There's no guarantee EnumValueName is still present in Enum, in which case Value will be set to the enum's max value.
        // On save, it will then be serialized as NAME_None.
        int32 EnumIndex = Enum->GetIndexByName(EnumValueName, EGetByNameFlags::ErrorIfNotFound);
        if (EnumIndex == INDEX_NONE)
        {
            *(uint8*)Value = Enum->GetMaxEnumValue();
        }
        else
        {
            *(uint8*)Value = Enum->GetValueByIndex(EnumIndex);
        }
    }
    // Saving
    else
    {
        FName EnumValueName;
        uint8 ByteValue = *(uint8*)Value;

        // subtract 1 because the last entry in the enum's Names array
        // is the _MAX entry
        if (Enum->IsValidEnumValue(ByteValue))
        {
            EnumValueName = Enum->GetNameByValue(ByteValue);
        }
        else
        {
            EnumValueName = NAME_None;
        }
        Slot << EnumValueName;
    }
}
bool FByteProperty::NetSerializeItem(FArchive& Ar, UPackageMap* Map, void* Data, TArray<uint8>* MetaData) const
{
    if (Ar.EngineNetVer() < HISTORY_ENUM_SERIALIZATION_COMPAT)
    {
        Ar.SerializeBits(Data, Enum ? FMath::CeilLogTwo(Enum->GetMaxEnumValue()) : 8);
    }
    else
    {
        Ar.SerializeBits(Data, GetMaxNetSerializeBits());
    }

    return true;
}
void FByteProperty::Serialize(FArchive& Ar)
{
    Super::Serialize(Ar);
    Ar << Enum;
    if (Enum != nullptr)
    {
        Ar.Preload(Enum);
    }
}

void FByteProperty::PostDuplicate(const FField& InField)
{
    const FByteProperty& Source = static_cast<const FByteProperty&>(InField);
    Enum                        = Source.Enum;
    Super::PostDuplicate(InField);
}

void FByteProperty::AddReferencedObjects(FReferenceCollector& Collector)
{
    Collector.AddReferencedObject(Enum, nullptr);
    Super::AddReferencedObjects(Collector);
}
FString FByteProperty::GetCPPType(FString* ExtendedTypeText /*=NULL*/, uint32 CPPExportFlags /*=0*/) const
{
    if (Enum)
    {
        const bool bEnumClassForm = Enum->GetCppForm() == UEnum::ECppForm::EnumClass;
        const bool bNonNativeEnum = Enum->GetClass() != UEnum::StaticClass();  // cannot use RF_Native flag, because in UHT the flag is not set
        const bool bRawParam      = (CPPExportFlags & CPPF_ArgumentOrReturnValue) && (((PropertyFlags & CPF_ReturnParm) || !(PropertyFlags & CPF_OutParm)) || bNonNativeEnum);
        const bool bConvertedCode = (CPPExportFlags & CPPF_BlueprintCppBackend) && bNonNativeEnum;

        FString FullyQualifiedEnumName;
        if (!Enum->CppType.IsEmpty())
        {
            FullyQualifiedEnumName = Enum->CppType;
        }
        else
        {
            // This would give the wrong result if it's a namespaced type and the CppType hasn't
            // been set, but we do this here in case existing code relies on it... somehow.
            if ((CPPExportFlags & CPPF_BlueprintCppBackend) && bNonNativeEnum)
            {
                ensure(Enum->CppType.IsEmpty());
                FullyQualifiedEnumName = ::UnicodeToCPPIdentifier(Enum->GetName(), false, TEXT("E__"));
            }
            else
            {
                FullyQualifiedEnumName = Enum->GetName();
            }
        }

        if (bEnumClassForm || bRawParam || bConvertedCode)
        {
            return FullyQualifiedEnumName;
        }
        else
        {
            return FString::Printf(TEXT("TEnumAsByte<%s>"), *FullyQualifiedEnumName);
        }
    }
    return Super::GetCPPType(ExtendedTypeText, CPPExportFlags);
}

template <typename OldIntType>
struct TConvertIntToEnumProperty
{
    static void Convert(FStructuredArchive::FSlot Slot, FByteProperty* Property, UEnum* Enum, void* Obj, const FPropertyTag& Tag)
    {
        OldIntType OldValue;
        Slot << OldValue;

        uint8 NewValue = OldValue;
        if (OldValue > (OldIntType)TNumericLimits<uint8>::Max() || !Enum->IsValidEnumValue(NewValue))
        {
            UE_LOG(
                LogClass,
                Warning,
                TEXT("Failed to find valid enum value '%d' for enum type '%s' when converting property '%s' during property loading - setting to '%s'"),
                OldValue,
                *Enum->GetName(),
                *Property->GetName(),
                *Enum->GetNameByValue(Enum->GetMaxEnumValue()).ToString());

            NewValue = Enum->GetMaxEnumValue();
        }

        Property->SetPropertyValue_InContainer(Obj, NewValue, Tag.ArrayIndex);
    }
};

EConvertFromTypeResult FByteProperty::ConvertFromType(const FPropertyTag& Tag, FStructuredArchive::FSlot Slot, uint8* Data, UStruct* DefaultsStruct)
{
    if (Tag.Type == NAME_ByteProperty && ((Tag.EnumName == NAME_None) != (Enum == nullptr)))
    {
        // a byte property gained or lost an enum
        // attempt to convert it
        uint8 PreviousValue = 0;
        if (Tag.EnumName == NAME_None)
        {
            // If we're a nested property the EnumName tag got lost. Fail to read in this case
            FProperty* const PropertyOwner = GetOwner<FProperty>();
            if (PropertyOwner)
            {
                return EConvertFromTypeResult::UseSerializeItem;
            }

            // simply pretend the property still doesn't have an enum and serialize the single byte
            Slot << PreviousValue;
        }
        else
        {
            // attempt to find the old enum and get the byte value from the serialized enum name
            PreviousValue = (uint8)ReadEnumAsInt64(Slot, DefaultsStruct, Tag);
        }

        // now copy the value into the object's address space
        SetPropertyValue_InContainer(Data, PreviousValue, Tag.ArrayIndex);
    }
    else if (Tag.Type == NAME_EnumProperty && (Enum == nullptr || Tag.EnumName == Enum->GetFName()))
    {
        // an enum property became a byte
        // attempt to find the old enum and get the byte value from the serialized enum name
        uint8 PreviousValue = (uint8)ReadEnumAsInt64(Slot, DefaultsStruct, Tag);

        // now copy the value into the object's address space
        SetPropertyValue_InContainer(Data, PreviousValue, Tag.ArrayIndex);
    }
    else if (Tag.Type == NAME_Int8Property)
    {
        if (Enum)
        {
            TConvertIntToEnumProperty<int8>::Convert(Slot, this, Enum, Data, Tag);
        }
        else
        {
            ConvertFromArithmeticValue<int8>(Slot, Data, Tag);
        }
    }
    else if (Tag.Type == NAME_Int16Property)
    {
        if (Enum)
        {
            TConvertIntToEnumProperty<int16>::Convert(Slot, this, Enum, Data, Tag);
        }
        else
        {
            ConvertFromArithmeticValue<int16>(Slot, Data, Tag);
        }
    }
    else if (Tag.Type == NAME_IntProperty)
    {
        if (Enum)
        {
            TConvertIntToEnumProperty<int32>::Convert(Slot, this, Enum, Data, Tag);
        }
        else
        {
            ConvertFromArithmeticValue<int32>(Slot, Data, Tag);
        }
    }
    else if (Tag.Type == NAME_Int64Property)
    {
        if (Enum)
        {
            TConvertIntToEnumProperty<int64>::Convert(Slot, this, Enum, Data, Tag);
        }
        else
        {
            ConvertFromArithmeticValue<int64>(Slot, Data, Tag);
        }
    }
    else if (Tag.Type == NAME_UInt16Property)
    {
        if (Enum)
        {
            TConvertIntToEnumProperty<uint16>::Convert(Slot, this, Enum, Data, Tag);
        }
        else
        {
            ConvertFromArithmeticValue<uint16>(Slot, Data, Tag);
        }
    }
    else if (Tag.Type == NAME_UInt32Property)
    {
        if (Enum)
        {
            TConvertIntToEnumProperty<uint32>::Convert(Slot, this, Enum, Data, Tag);
        }
        else
        {
            ConvertFromArithmeticValue<uint32>(Slot, Data, Tag);
        }
    }
    else if (Tag.Type == NAME_UInt64Property)
    {
        if (Enum)
        {
            TConvertIntToEnumProperty<uint64>::Convert(Slot, this, Enum, Data, Tag);
        }
        else
        {
            ConvertFromArithmeticValue<uint64>(Slot, Data, Tag);
        }
    }
    else
    {
        return EConvertFromTypeResult::UseSerializeItem;
    }

    return EConvertFromTypeResult::Converted;
}

void FByteProperty::ExportTextItem(FString& ValueStr, const void* PropertyValue, const void* DefaultValue, UObject* Parent, int32 PortFlags, UObject* ExportRootScope) const
{
    if (0 != (PortFlags & PPF_ExportCpp))
    {
        if (Enum)
        {
            const int32 ActualValue   = *(const uint8*)PropertyValue;
            const int32 MaxValue      = Enum->GetMaxEnumValue();
            const int32 GoodValue     = Enum->IsValidEnumValue(ActualValue) ? ActualValue : MaxValue;
            const bool bNonNativeEnum = Enum->GetClass() != UEnum::StaticClass();
            ensure(!bNonNativeEnum || Enum->CppType.IsEmpty());
            const FString FullyQualifiedEnumName = bNonNativeEnum ? ::UnicodeToCPPIdentifier(Enum->GetName(), false, TEXT("E__")) : (Enum->CppType.IsEmpty() ? Enum->GetName() : Enum->CppType);
            if (GoodValue == MaxValue)
            {
                // not all native enums have Max value declared
                ValueStr += FString::Printf(TEXT("(%s)(%d)"), *FullyQualifiedEnumName, ActualValue);
            }
            else
            {
                ValueStr += FString::Printf(TEXT("%s::%s"), *FullyQualifiedEnumName,
                                            *Enum->GetNameStringByValue(GoodValue));
            }
        }
        else
        {
            Super::ExportTextItem(ValueStr, PropertyValue, DefaultValue, Parent, PortFlags, ExportRootScope);
        }
        return;
    }

    if (Enum && (PortFlags & PPF_ConsoleVariable) == 0)
    {
        // if the value is the max value (the autogenerated *_MAX value), export as "INVALID", unless we're exporting text for copy/paste (for copy/paste,
        // the property text value must actually match an entry in the enum's names array)
        bool bIsValid = Enum->IsValidEnumValue(*(const uint8*)PropertyValue);
        bool bIsMax   = *(const uint8*)PropertyValue == Enum->GetMaxEnumValue();
        if (bIsValid && (!bIsMax || (PortFlags & PPF_Copy)))
        {
            // We do not want to export the enum text for non-display uses, localization text is very dynamic and would cause issues on import
            if (PortFlags & PPF_PropertyWindow)
            {
                ValueStr += Enum->GetDisplayNameTextByValue(*(const uint8*)PropertyValue).ToString();
            }
            else if (PortFlags & PPF_ExternalEditor)
            {
                ValueStr += Enum->GetAuthoredNameStringByValue(*(const uint8*)PropertyValue);
            }
            else
            {
                ValueStr += Enum->GetNameStringByValue(*(const uint8*)PropertyValue);
            }
        }
        else
        {
            ValueStr += TEXT("(INVALID)");
        }
    }
    else
    {
        Super::ExportTextItem(ValueStr, PropertyValue, DefaultValue, Parent, PortFlags, ExportRootScope);
    }
}
const TCHAR* FByteProperty::ImportText_Internal(const TCHAR* InBuffer, void* Data, int32 PortFlags, UObject* Parent, FOutputDevice* ErrorText) const
{
    if (Enum && (PortFlags & PPF_ConsoleVariable) == 0)
    {
        FString Temp;
        if (const TCHAR* Buffer = FPropertyHelpers::ReadToken(InBuffer, Temp, true))
        {
            int32 EnumIndex = Enum->GetIndexByName(*Temp, EGetByNameFlags::CheckAuthoredName);
            if (EnumIndex == INDEX_NONE && (Temp.IsNumeric() && !Algo::Find(Temp, TEXT('.'))))
            {
                int64 EnumValue = INDEX_NONE;
                LexFromString(EnumValue, *Temp);
                EnumIndex = Enum->GetIndexByValue(EnumValue);
            }
            if (EnumIndex != INDEX_NONE)
            {
                *(uint8*)Data = Enum->GetValueByIndex(EnumIndex);
                return Buffer;
            }

            // Enum could not be created from value. This indicates a bad value so
            // return null so that the caller of ImportText can generate a more meaningful
            // warning/error
            UObject* SerializedObject = nullptr;
            if (FLinkerLoad* Linker = GetLinker())
            {
                if (FUObjectSerializeContext* LoadContext = Linker->GetSerializeContext())
                {
                    SerializedObject = LoadContext->SerializedObject;
                }
            }
            UE_LOG(LogClass, Warning, TEXT("In asset '%s', there is an enum property of type '%s' with an invalid value of '%s'"), *GetPathNameSafe(SerializedObject ? SerializedObject : FUObjectThreadContext::Get().ConstructedObject), *Enum->GetName(), *Temp);
            return nullptr;
        }
    }

    // Interpret "True" and "False" as 1 and 0. This is mostly for importing a property that was exported as a bool and is imported as a non-enum byte.
    if (!Enum)
    {
        FString Temp;
        if (const TCHAR* Buffer = FPropertyHelpers::ReadToken(InBuffer, Temp))
        {
            const FCoreTexts& CoreTexts = FCoreTexts::Get();

            if (Temp == TEXT("True") || Temp == *(CoreTexts.True.ToString()))
            {
                SetIntPropertyValue(Data, 1ull);
                return Buffer;
            }
            else if (Temp == TEXT("False") || Temp == *(CoreTexts.False.ToString()))
            {
                SetIntPropertyValue(Data, 0ull);
                return Buffer;
            }
        }
    }

    return Super::ImportText_Internal(InBuffer, Data, PortFlags, Parent, ErrorText);
}

UEnum* FByteProperty::GetIntPropertyEnum() const
{
    return Enum;
}

uint64 FByteProperty::GetMaxNetSerializeBits() const
{
    const uint64 MaxBits     = 8;
    const uint64 DesiredBits = Enum ? FMath::CeilLogTwo64(Enum->GetMaxEnumValue() + 1) : MaxBits;

    return FMath::Min(DesiredBits, MaxBits);
}

#include "UObject/DefineUPropertyMacros.h"