// Portage UE 5.5 - voir LPFixZeroScaleActorsCommandlet.h

#include "LPFixZeroScaleActorsCommandlet.h"

#include "AssetRegistry/AssetRegistryModule.h"
#include "Components/SceneComponent.h"
#include "Components/PrimitiveComponent.h"
#include "Components/StaticMeshComponent.h"
#include "Engine/StaticMesh.h"
#include "Engine/World.h"
#include "GameFramework/Actor.h"
#include "Misc/PackageName.h"
#include "UObject/Package.h"
#include "UObject/SavePackage.h"
#include "UObject/UObjectGlobals.h"

DEFINE_LOG_CATEGORY_STATIC(LogLPFixZeroScale, Log, All);

namespace
{
	/** Seuil du moteur : FMath::IsNearlyZero sur chaque composante avant creation du body. */
	constexpr double ZeroScaleTolerance = UE_KINDA_SMALL_NUMBER;

	/** Decrit le maillage porte par un composant, pour pouvoir juger de la valeur a remettre. */
	FString DescribeMesh(const USceneComponent* Component)
	{
		const UStaticMeshComponent* MeshComponent = Cast<UStaticMeshComponent>(Component);
		if (!MeshComponent || !MeshComponent->GetStaticMesh())
		{
			return TEXT("(pas de maillage statique)");
		}

		const UStaticMesh* Mesh = MeshComponent->GetStaticMesh();
		const FBoxSphereBounds Bounds = Mesh->GetBounds();
		return FString::Printf(TEXT("%s  demi-dimensions locales (X=%.2f Y=%.2f Z=%.2f)"),
			*Mesh->GetPathName(),
			Bounds.BoxExtent.X, Bounds.BoxExtent.Y, Bounds.BoxExtent.Z);
	}

	/**
	 * Visibilite et collision : ce sont elles qui dictent la valeur de remplacement.
	 * Un bloqueur invisible tolere une epaisseur quelconque ; un mur visible non.
	 */
	FString DescribeRendering(const USceneComponent* Component)
	{
		const UPrimitiveComponent* Primitive = Cast<UPrimitiveComponent>(Component);
		if (!Primitive)
		{
			return TEXT("(pas un composant primitif)");
		}

		const UEnum* CollisionEnum = StaticEnum<ECollisionEnabled::Type>();
		const ECollisionEnabled::Type Collision = Primitive->GetCollisionEnabled();

		return FString::Printf(TEXT("visible=%s  cacheEnJeu=%s  collision=%s  profil=%s"),
			Primitive->IsVisible() ? TEXT("oui") : TEXT("NON"),
			Primitive->bHiddenInGame ? TEXT("oui") : TEXT("non"),
			CollisionEnum ? *CollisionEnum->GetNameStringByValue(static_cast<int64>(Collision)) : TEXT("?"),
			*Primitive->GetCollisionProfileName().ToString());
	}
}

ULPFixZeroScaleActorsCommandlet::ULPFixZeroScaleActorsCommandlet()
{
	IsClient = false;
	IsServer = false;
	IsEditor = true;
	LogToConsole = true;
}

int32 ULPFixZeroScaleActorsCommandlet::Main(const FString& Params)
{
	TArray<FString> Tokens;
	TArray<FString> Switches;
	TMap<FString, FString> ParamsMap;
	ParseCommandLine(*Params, Tokens, Switches, ParamsMap);

	const bool bFix = Switches.Contains(TEXT("Fix"));
	double Replacement = 1.0;
	if (const FString* ScaleText = ParamsMap.Find(TEXT("Scale")))
	{
		Replacement = FCString::Atod(**ScaleText);
	}
	// Garde-fou volontaire : PowerShell coupe « -Scale=0.1 » en deux arguments si on ne le
	// guillemette pas, et la commandlet recevrait alors 0 sans rien dire. Voir l'en-tete.
	if (bFix && FMath::IsNearlyZero(Replacement, ZeroScaleTolerance))
	{
		UE_LOG(LogLPFixZeroScale, Error,
			TEXT("-Scale lu a %f : valeur nulle ou argument coupe par le shell. Guillemettez \"-Scale=0.1\"."),
			Replacement);
		return 1;
	}

	UE_LOG(LogLPFixZeroScale, Warning, TEXT("=== Composantes d'echelle nulles (R-06)%s ==="),
		bFix ? *FString::Printf(TEXT(" [CORRECTION -> %.4f]"), Replacement) : TEXT(" [RAPPORT SEUL]"));

	FAssetRegistryModule& AssetRegistryModule =
		FModuleManager::LoadModuleChecked<FAssetRegistryModule>(TEXT("AssetRegistry"));
	AssetRegistryModule.Get().SearchAllAssets(true);

	TArray<FAssetData> MapAssets;
	AssetRegistryModule.Get().GetAssetsByClass(UWorld::StaticClass()->GetClassPathName(), MapAssets, true);

	int32 ComponentsFound = 0;
	int32 ComponentsFixed = 0;
	int32 MapsModified = 0;
	int32 SaveFailures = 0;

	for (const FAssetData& AssetData : MapAssets)
	{
		const FString PackageName = AssetData.PackageName.ToString();
		if (!PackageName.StartsWith(TEXT("/Game/")))
		{
			continue;
		}

		UPackage* Package = LoadPackage(nullptr, *PackageName, LOAD_None);
		UWorld* World = Package ? UWorld::FindWorldInPackage(Package) : nullptr;
		if (!World || !World->PersistentLevel)
		{
			UE_LOG(LogLPFixZeroScale, Warning, TEXT("  %s : monde illisible, ignore."), *PackageName);
			continue;
		}

		int32 FixedHere = 0;

		for (AActor* Actor : World->PersistentLevel->Actors)
		{
			if (!Actor)
			{
				continue;
			}

			TArray<USceneComponent*> Components;
			Actor->GetComponents<USceneComponent>(Components);

			for (USceneComponent* Component : Components)
			{
				if (!Component)
				{
					continue;
				}

				FVector Scale = Component->GetRelativeScale3D();
				const bool bZeroX = FMath::IsNearlyZero(Scale.X, ZeroScaleTolerance);
				const bool bZeroY = FMath::IsNearlyZero(Scale.Y, ZeroScaleTolerance);
				const bool bZeroZ = FMath::IsNearlyZero(Scale.Z, ZeroScaleTolerance);
				if (!bZeroX && !bZeroY && !bZeroZ)
				{
					continue;
				}

				++ComponentsFound;
				UE_LOG(LogLPFixZeroScale, Warning, TEXT("  %s : %s.%s"),
					*PackageName, *Actor->GetName(), *Component->GetName());
				UE_LOG(LogLPFixZeroScale, Warning, TEXT("      echelle  : X=%.4f Y=%.4f Z=%.4f"),
					Scale.X, Scale.Y, Scale.Z);
				UE_LOG(LogLPFixZeroScale, Warning, TEXT("      maillage : %s"), *DescribeMesh(Component));
				UE_LOG(LogLPFixZeroScale, Warning, TEXT("      rendu    : %s"), *DescribeRendering(Component));

				if (!bFix)
				{
					continue;
				}

				if (bZeroX) { Scale.X = Replacement; }
				if (bZeroY) { Scale.Y = Replacement; }
				if (bZeroZ) { Scale.Z = Replacement; }

				Actor->Modify();
				Component->Modify();
				Component->SetRelativeScale3D(Scale);
				Component->MarkRenderStateDirty();
				// Recalcule le corps physique avec la nouvelle echelle.
				Component->RecreatePhysicsState();

				UE_LOG(LogLPFixZeroScale, Warning, TEXT("      -> X=%.4f Y=%.4f Z=%.4f"),
					Scale.X, Scale.Y, Scale.Z);

				++ComponentsFixed;
				++FixedHere;
			}
		}

		if (FixedHere > 0)
		{
			++MapsModified;

			FString Filename;
			if (!FPackageName::TryConvertLongPackageNameToFilename(
					PackageName, Filename, FPackageName::GetMapPackageExtension()))
			{
				++SaveFailures;
				UE_LOG(LogLPFixZeroScale, Error, TEXT("  chemin introuvable pour %s"), *PackageName);
				continue;
			}

			Package->MarkPackageDirty();

			FSavePackageArgs SaveArgs;
			SaveArgs.TopLevelFlags = RF_Public | RF_Standalone;
			SaveArgs.SaveFlags = SAVE_None;
			SaveArgs.bWarnOfLongFilename = true;
			SaveArgs.Error = GWarn;

			if (UPackage::SavePackage(Package, World, *Filename, SaveArgs))
			{
				UE_LOG(LogLPFixZeroScale, Warning, TEXT("  -> %s sauvegarde (%d composant(s))."), *PackageName, FixedHere);
			}
			else
			{
				++SaveFailures;
				UE_LOG(LogLPFixZeroScale, Error, TEXT("  -> ECHEC de sauvegarde de %s"), *PackageName);
			}
		}
	}

	UE_LOG(LogLPFixZeroScale, Warning,
		TEXT("=== Termine : %d composant(s) a echelle nulle, %d corrige(s) dans %d carte(s), %d echec(s) de sauvegarde. ==="),
		ComponentsFound, ComponentsFixed, MapsModified, SaveFailures);

	return SaveFailures > 0 ? 1 : 0;
}