// Lot STM1 (COMMUN-28 S6). Voir LPDumpMaterialCommandlet.h.

#include "LPDumpMaterialCommandlet.h"

#include "Materials/Material.h"
#include "Materials/MaterialExpression.h"
#include "Misc/FileHelper.h"
#include "UObject/UnrealType.h"

DEFINE_LOG_CATEGORY_STATIC(LogLPDumpMaterial, Log, All);

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

int32 ULPDumpMaterialCommandlet::Main(const FString& Params)
{
	TArray<FString> Tokens, Switches;
	TMap<FString, FString> ParamsMap;
	ParseCommandLine(*Params, Tokens, Switches, ParamsMap);
	const FString ReportPath = ParamsMap.FindRef(TEXT("Report"));
	TArray<FString> Paths;
	ParamsMap.FindRef(TEXT("Material")).ParseIntoArray(Paths, TEXT(";"));

	TArray<FString> Report;
	auto Line = [&Report](const FString& Text)
	{
		UE_LOG(LogLPDumpMaterial, 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 (Paths.IsEmpty())
	{
		Line(TEXT("usage : -Material=<objet>[;<objet>...] [-Report=<f.md>]"));
		return Finish(2);
	}

	for (const FString& Path : Paths)
	{
		UMaterial* Material = LoadObject<UMaterial>(nullptr, *Path);
		Line(FString::Printf(TEXT("# %s"), *Path));
		if (!Material)
		{
			Line(TEXT("ECHEC : UMaterial introuvable"));
			return Finish(1);
		}
		const TConstArrayView<TObjectPtr<UMaterialExpression>> Expressions = Material->GetExpressions();
		auto IndexOf = [&Expressions](const UMaterialExpression* E)
		{
			for (int32 I = 0; I < Expressions.Num(); ++I) if (Expressions[I] == E) return I;
			return int32(INDEX_NONE);
		};
		Line(FString::Printf(TEXT("domaine %s ; melange %s ; ombrage %s ; deux faces %d ; noeuds %d"),
			*StaticEnum<EMaterialDomain>()->GetNameStringByValue(int64(Material->MaterialDomain)),
			*StaticEnum<EBlendMode>()->GetNameStringByValue(int64(Material->BlendMode)),
			*StaticEnum<EMaterialShadingModel>()->GetNameStringByValue(int64(Material->GetShadingModels().GetFirstShadingModel())),
			Material->IsTwoSided() ? 1 : 0, Expressions.Num()));
		if (const UMaterialEditorOnlyData* Data = Material->GetEditorOnlyData())
		{
			const TPair<const TCHAR*, const FExpressionInput*> Inputs[] = {
				{ TEXT("BaseColor"), &Data->BaseColor }, { TEXT("EmissiveColor"), &Data->EmissiveColor }, { TEXT("Normal"), &Data->Normal },
				{ TEXT("Metallic"), &Data->Metallic }, { TEXT("Roughness"), &Data->Roughness }, { TEXT("Specular"), &Data->Specular },
				{ TEXT("Opacity"), &Data->Opacity }, { TEXT("OpacityMask"), &Data->OpacityMask }, { TEXT("WorldPositionOffset"), &Data->WorldPositionOffset } };
			for (const TPair<const TCHAR*, const FExpressionInput*>& Input : Inputs)
			{
				if (Input.Value->Expression)
				{
					Line(FString::Printf(TEXT("entree %s <- noeud %d (%s), sortie %d"), Input.Key, IndexOf(Input.Value->Expression),
						*Input.Value->Expression->GetClass()->GetName(), Input.Value->OutputIndex));
				}
			}
		}
		for (int32 I = 0; I < Expressions.Num(); ++I)
		{
			UMaterialExpression* E = Expressions[I];
			if (!E) continue;
			TArray<FString> Props;
			for (TFieldIterator<FProperty> It(E->GetClass(), EFieldIteratorFlags::ExcludeSuper); It; ++It)
			{
				if (CastField<FStructProperty>(*It) && CastField<FStructProperty>(*It)->Struct->GetName().Contains(TEXT("ExpressionInput"))) continue;
				FString Value;
				It->ExportTextItem_InContainer(Value, E, nullptr, nullptr, PPF_None);
				if (Value.Len() > 120) Value = Value.Left(120) + TEXT("...");
				Props.Add(FString::Printf(TEXT("%s=%s"), *It->GetName(), *Value));
			}
			TArray<FString> Links;
			for (FExpressionInputIterator It{ E }; It; ++It)
			{
				if (It->Expression)
				{
					Links.Add(FString::Printf(TEXT("%s<-%d"), *E->GetInputName(It.Index).ToString(), IndexOf(It->Expression)));
				}
			}
			Line(FString::Printf(TEXT("  [%d] %s \"%s\" | %s | entrees : %s"), I, *E->GetClass()->GetName(), *E->GetDescription(),
				*FString::Join(Props, TEXT(" ; ")), Links.IsEmpty() ? TEXT("-") : *FString::Join(Links, TEXT(", "))));
		}
	}
	return Finish(0);
}