// Lot STM1 (1.2.2). Voir LPSetMaterialUsageCommandlet.h.

#include "LPSetMaterialUsageCommandlet.h"

#include "AssetRegistry/AssetRegistryModule.h"
#include "HAL/FileManager.h"
#include "Materials/Material.h"
#include "Misc/FileHelper.h"
#include "Misc/PackageName.h"
#include "UObject/Package.h"
#include "UObject/SavePackage.h"

DEFINE_LOG_CATEGORY_STATIC(LogLPSetMaterialUsage, Log, All);

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

int32 ULPSetMaterialUsageCommandlet::Main(const FString& Params)
{
	TArray<FString> Tokens, Switches;
	TMap<FString, FString> ParamsMap;
	ParseCommandLine(*Params, Tokens, Switches, ParamsMap);
	const FString Folder = ParamsMap.FindRef(TEXT("Folder"));
	const FString ReportPath = ParamsMap.FindRef(TEXT("Report"));
	const bool bDryRun = Switches.Contains(TEXT("DryRun"));

	TArray<FString> Report;
	auto Line = [&Report](const FString& Text)
	{
		UE_LOG(LogLPSetMaterialUsage, Display, TEXT("%s"), *Text);
		Report.Add(Text);
	};
	auto Finish = [&](int32 Code)
	{
		Line(FString::Printf(TEXT("CODE %d"), Code));
		if (!ReportPath.IsEmpty())
		{
			FFileHelper::SaveStringArrayToFile(Report, *ReportPath, FFileHelper::EEncodingOptions::ForceUTF8WithoutBOM);
		}
		return Code;
	};

	if (Folder.IsEmpty())
	{
		Line(TEXT("usage : -Folder=</lpm_city_<v>/Houses> [-DryRun] [-Report=<f.md>]"));
		return Finish(2);
	}
	Line(FString::Printf(TEXT("# LPSetMaterialUsage %s (%s) : bUsedWithInstancedStaticMeshes"), *Folder, bDryRun ? TEXT("DryRun") : TEXT("ecriture")));
	TArray<FString> Parts;
	Folder.ParseIntoArray(Parts, TEXT("/"));
	if (!(Folder.StartsWith(TEXT("/Game/Heavy/StreetMap/")) || (Parts.Num() >= 1 && Parts[0].StartsWith(TEXT("lpm_city_")))))
	{
		Line(TEXT("ECHEC : dossier hors de /lpm_city_*/ et de /Game/Heavy/StreetMap/ ; rien modifie"));
		return Finish(1);
	}

	IAssetRegistry& Registry = FModuleManager::LoadModuleChecked<FAssetRegistryModule>(TEXT("AssetRegistry")).Get();
	Registry.ScanPathsSynchronous({ Folder }, /*bForceRescan=*/true);
	TArray<FAssetData> Assets;
	Registry.GetAssetsByPath(FName(*Folder), Assets, /*bRecursive=*/true);
	Assets.RemoveAll([](const FAssetData& A) { return A.AssetClassPath != UMaterial::StaticClass()->GetClassPathName(); });
	Assets.Sort([](const FAssetData& A, const FAssetData& B) { return A.PackageName.LexicalLess(B.PackageName); });

	int32 Already = 0, Set = 0, Saved = 0;
	for (const FAssetData& Data : Assets)
	{
		UMaterial* Material = Cast<UMaterial>(Data.GetAsset());
		if (!Material)
		{
			Line(FString::Printf(TEXT("ECHEC : %s illisible ; arret"), *Data.GetObjectPathString()));
			return Finish(1);
		}
		if (Material->GetUsageByFlag(MATUSAGE_InstancedStaticMeshes))
		{
			++Already;
			Line(FString::Printf(TEXT("%s : deja coche"), *Data.GetObjectPathString()));
			continue;
		}
		++Set;
		if (bDryRun)
		{
			Line(FString::Printf(TEXT("%s : a cocher (DryRun)"), *Data.GetObjectPathString()));
			continue;
		}
		Material->Modify();
		Material->SetUsageByFlag(MATUSAGE_InstancedStaticMeshes, true);
		Material->PostEditChange();
		UPackage* Package = Material->GetPackage();
		FSavePackageArgs SaveArgs;
		SaveArgs.TopLevelFlags = RF_Public | RF_Standalone;
		const FString File = FPackageName::LongPackageNameToFilename(Package->GetName(), FPackageName::GetAssetPackageExtension());
		if (!UPackage::SavePackage(Package, Material, *File, SaveArgs))
		{
			Line(FString::Printf(TEXT("ECHEC : sauvegarde de %s"), *Package->GetName()));
			return Finish(1);
		}
		++Saved;
		Line(FString::Printf(TEXT("%s : coche, ecrit (%lld octets)"), *Data.GetObjectPathString(), IFileManager::Get().FileSize(*File)));
	}
	Line(FString::Printf(TEXT("materiaux %d ; deja coches %d ; coches %d ; paquets ecrits %d"), Assets.Num(), Already, Set, Saved));
	return Finish(0);
}