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

#include "Factories/Texture2DArrayFactory.h"
#include "Styling/SlateBrush.h"
#include "Brushes/SlateDynamicImageBrush.h"
#include "Engine/Texture2DArray.h"

#define LOCTEXT_NAMESPACE "Texture2DArrayFactory"

UTexture2DArrayFactory::UTexture2DArrayFactory(const FObjectInitializer& ObjectInitializer)
    : Super(ObjectInitializer)
{
    bCreateNew     = true;
    bEditAfterNew  = true;
    SupportedClass = UTexture2DArray::StaticClass();
}

FText UTexture2DArrayFactory::GetDisplayName() const
{
    return LOCTEXT("Texture2DArrayFactoryDescription", "Texture 2D Array");
}

bool UTexture2DArrayFactory::ConfigureProperties()
{
    return true;
}

bool UTexture2DArrayFactory::CanCreateNew() const
{
    static const auto AllowTextureArrayAssetCreationVar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.AllowTexture2DArrayCreation"));
    return (AllowTextureArrayAssetCreationVar->GetValueOnGameThread() == 1);
}

UObject* UTexture2DArrayFactory::FactoryCreateNew(UClass* Class, UObject* InParent, FName Name, EObjectFlags Flags, UObject* Context, FFeedbackContext* Warn)
{
    static const auto AllowTextureArrayAssetCreationVar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.AllowTexture2DArrayCreation"));

    if (AllowTextureArrayAssetCreationVar->GetValueOnGameThread() == 0)
    {
        UE_LOG(LogTexture, Warning, TEXT("Texture2DArray creation failed. Enable by using console command r.AllowTexture2DArrayCreation\n"));
        return nullptr;
    }

    // Make sure the size of all textures is the same.
    if (!CheckArrayTexturesCompatibility())
    {
        return nullptr;
    }

    UTexture2DArray* NewTexture2DArray = CastChecked<UTexture2DArray>(CreateOrOverwriteAsset(UTexture2DArray::StaticClass(), InParent, Name, Flags));

    if (NewTexture2DArray == 0)
    {
        UE_LOG(LogTexture, Warning, TEXT("Texture2DArray creation failed.\n"));
    }
    else if (InitialTextures.Num() > 0)
    {
        // Upload the compatible textures to the texture array.
        for (int32 TextureIndex = 0; TextureIndex < InitialTextures.Num(); ++TextureIndex)
        {
            NewTexture2DArray->SourceTextures.Add(InitialTextures[TextureIndex]);
        }

        // Create the texture array resource and corresponding rhi resource.
        NewTexture2DArray->UpdateSourceFromSourceTextures();
    }

    return NewTexture2DArray;
}

bool UTexture2DArrayFactory::CheckArrayTexturesCompatibility()
{
    bool bError = false;
    for (int32 TextureIndex = 0; TextureIndex < InitialTextures.Num(); ++TextureIndex)
    {
        FTextureSource& TextureSource = InitialTextures[TextureIndex]->Source;
        const int32 FormatDataSize    = TextureSource.GetBytesPerPixel();
        const int32 SizeX             = TextureSource.GetSizeX();
        const int32 SizeY             = TextureSource.GetSizeY();

        for (int32 TextureCmpIndex = TextureIndex + 1; TextureCmpIndex < InitialTextures.Num(); ++TextureCmpIndex)
        {
            FTextureSource& TextureSourceCmp = InitialTextures[TextureCmpIndex]->Source;
            if (TextureSourceCmp.GetSizeX() != SizeX || TextureSourceCmp.GetSizeY() != SizeY)
            {
                UE_LOG(LogTexture, Warning, TEXT("Texture2DArray creation failed. Textures have different sizes."));
                bError = true;
            }

            if (TextureSourceCmp.GetBytesPerPixel() != FormatDataSize)
            {
                UE_LOG(LogTexture, Warning, TEXT("Texture2DArray creation failed. Textures have different pixel formats."));
                bError = true;
            }
        }
    }

    return (!bError);
}

#undef LOCTEXT_NAMESPACE