// Portage UE 5.5 - lot debug. Voir LPDebugSubsystem.h.

#include "LPDebugSubsystem.h"

#include "LifePlay.h"

#if !UE_BUILD_SHIPPING

#include "Chaos/TriangleMeshImplicitObject.h"
#include "Components/PrimitiveComponent.h"
#include "Components/StaticMeshComponent.h"
#include "Engine/Engine.h"
#include "Engine/World.h"
#include "EngineUtils.h"
#include "HAL/FileManager.h"
#include "HAL/IConsoleManager.h"
#include "HAL/PlatformMemory.h"
#include "Misc/CommandLine.h"
#include "Misc/CoreDelegates.h"
#include "Misc/FileHelper.h"
#include "Misc/Parse.h"
#include "Misc/Paths.h"
#include "PhysicsEngine/BodySetup.h"
#include "ProfilingDebugging/MiscTrace.h"

namespace
{
	FAutoConsoleCommand* MemSnapshotCommand = nullptr;
	FAutoConsoleCommand* CollisionDumpCommand = nullptr;
	FAutoConsoleCommand* BookmarkCommand = nullptr;
	FAutoConsoleCommand* HitchSummaryCommand = nullptr;
	ULPDebugSubsystem* CommandOwner = nullptr;

	ULPDebugSubsystem* FindDebugSubsystem()
	{
		return CommandOwner;
	}

	UWorld* FindPlayWorld()
	{
		if (!GEngine)
		{
			return nullptr;
		}
		if (UWorld* Play = GEngine->GetCurrentPlayWorld())
		{
			return Play;
		}
		for (const FWorldContext& Context : GEngine->GetWorldContexts())
		{
			UWorld* World = Context.World();
			if (World && (World->WorldType == EWorldType::Game || World->WorldType == EWorldType::PIE))
			{
				return World;
			}
		}
		return nullptr;
	}

	FString DebugDir()
	{
		const FString Dir = FPaths::ProjectSavedDir() / TEXT("Profiling/LPDebug");
		IFileManager::Get().MakeDirectory(*Dir, true);
		return Dir;
	}

	void WriteMemSnapshot()
	{
		const FString Stamp = FDateTime::Now().ToString(TEXT("%Y%m%d_%H%M%S"));
		const FString Path = DebugDir() / FString::Printf(TEXT("MemSnapshot_%s.txt"), *Stamp);
		const FPlatformMemoryStats Stats = FPlatformMemory::GetStats();
		TArray<FString> Lines;
		Lines.Add(FString::Printf(TEXT("When=%s"), *FDateTime::Now().ToString()));
		Lines.Add(FString::Printf(TEXT("UsedPhysicalMB=%.1f"), Stats.UsedPhysical / (1024.0 * 1024.0)));
		Lines.Add(FString::Printf(TEXT("PeakUsedPhysicalMB=%.1f"), Stats.PeakUsedPhysical / (1024.0 * 1024.0)));
		Lines.Add(FString::Printf(TEXT("AvailablePhysicalMB=%.1f"), Stats.AvailablePhysical / (1024.0 * 1024.0)));
		Lines.Add(FString::Printf(TEXT("UsedVirtualMB=%.1f"), Stats.UsedVirtual / (1024.0 * 1024.0)));

		UWorld* World = FindPlayWorld();
		if (GEngine)
		{
			const bool bReport = GEngine->Exec(World, TEXT("memreport"));
			Lines.Add(FString::Printf(TEXT("memreport=%s"), bReport ? TEXT("ok") : TEXT("echec")));
		}
		const FString ReportDir = FPaths::ProjectSavedDir() / TEXT("Profiling/MemReports");
		TArray<FString> Reports;
		IFileManager::Get().FindFilesRecursive(Reports, *ReportDir, TEXT("*.memreport"), true, false);
		if (Reports.Num() > 0)
		{
			Reports.Sort();
			Lines.Add(FString::Printf(TEXT("NewestMemReport=%s"), *Reports.Last()));
		}
		Lines.Add(TEXT("PhysicsMB=voir LLM (colonne Physics) ou le MemReport ; ce fichier ne remplace pas la session B"));
		FFileHelper::SaveStringArrayToFile(Lines, *Path);
		UE_LOG(LogLifePlay, Display, TEXT("LPDebug MemSnapshot : %s"), *Path);
	}

	struct FCollisionOwner
	{
		FString Actor;
		FString ClassName;
		FString Component;
		FString Profile;
		int64 Triangles = 0;
		int32 TriMeshes = 0;
		int32 Simple = 0;
		int32 Capsules = 0;
	};

	struct FCollisionTally
	{
		FString WorldName;
		int32 Prim = 0;
		int32 Simulating = 0;
		int32 QueryOnly = 0;
		int32 Persons = 0;
		int32 Players = 0;
		int32 Street = 0;
		int32 UniqueBodies = 0;
		int32 UniqueSimple = 0;
		int32 UniqueTriMeshes = 0;
		int32 UniqueCapsules = 0;
		int64 Triangles = 0;
		TMap<FString, int32> ByClass;
		TMap<FString, int64> TrisByClass;
		TArray<FCollisionOwner> Owners;
	};

	int64 CountTriangles(const UBodySetup* Body)
	{
		int64 Count = 0;
		if (!Body)
		{
			return 0;
		}
		for (const Chaos::FTriangleMeshImplicitObjectPtr& Mesh : Body->TriMeshGeometries)
		{
			if (Mesh)
			{
				Count += Mesh->Elements().GetNumTriangles();
			}
		}
		return Count;
	}

	FString ComponentLabel(const UPrimitiveComponent* Prim)
	{
		if (const UStaticMeshComponent* MeshComp = Cast<UStaticMeshComponent>(Prim))
		{
			if (const UStaticMesh* Mesh = MeshComp->GetStaticMesh())
			{
				return Mesh->GetName();
			}
		}
		return Prim ? Prim->GetName() : FString();
	}

	FCollisionTally GatherCollision()
	{
		FCollisionTally Tally;
		UWorld* World = FindPlayWorld();
		Tally.WorldName = World ? World->GetName() : TEXT("(aucune)");
		if (!World)
		{
			return Tally;
		}

		TSet<const UBodySetup*> Bodies;
		for (TActorIterator<AActor> It(World); It; ++It)
		{
			const FString ClassName = It->GetClass()->GetName();
			TInlineComponentArray<UPrimitiveComponent*> Comps;
			It->GetComponents(Comps);
			for (UPrimitiveComponent* Prim : Comps)
			{
				if (!Prim || !Prim->IsCollisionEnabled())
				{
					continue;
				}
				++Tally.Prim;
				Tally.ByClass.FindOrAdd(ClassName)++;
				if (ClassName.StartsWith(TEXT("Person_C")))
				{
					++Tally.Persons;
				}
				else if (ClassName.StartsWith(TEXT("PC_C")))
				{
					++Tally.Players;
				}
				else if (ClassName.Contains(TEXT("StreetMap")))
				{
					++Tally.Street;
				}
				if (Prim->IsSimulatingPhysics())
				{
					++Tally.Simulating;
				}
				if (Prim->GetCollisionEnabled() == ECollisionEnabled::QueryOnly)
				{
					++Tally.QueryOnly;
				}

				UBodySetup* Body = Prim->GetBodySetup();
				if (!Body || Bodies.Contains(Body))
				{
					continue;
				}
				Bodies.Add(Body);
				const int64 Tris = CountTriangles(Body);
				const int32 Capsules = Body->AggGeom.SphylElems.Num();
				const int32 Simple = Body->AggGeom.GetElementCount();
				Tally.UniqueBodies++;
				Tally.UniqueSimple += Simple;
				Tally.UniqueCapsules += Capsules;
				Tally.UniqueTriMeshes += Body->TriMeshGeometries.Num();
				Tally.Triangles += Tris;
				Tally.TrisByClass.FindOrAdd(ClassName) += Tris;

				if (Tris > 0 || Simple > 0)
				{
					FCollisionOwner& Owner = Tally.Owners.AddDefaulted_GetRef();
					Owner.Actor = It->GetName();
					Owner.ClassName = ClassName;
					Owner.Component = ComponentLabel(Prim);
					Owner.Profile = Prim->GetCollisionProfileName().ToString();
					Owner.Triangles = Tris;
					Owner.TriMeshes = Body->TriMeshGeometries.Num();
					Owner.Simple = Simple;
					Owner.Capsules = Capsules;
				}
			}
		}

		Tally.Owners.Sort([](const FCollisionOwner& A, const FCollisionOwner& B)
		{
			return A.Triangles > B.Triangles;
		});
		return Tally;
	}

	FString WriteCollisionDump(const TCHAR* Reason, const FCollisionTally* Existing = nullptr)
	{
		const FCollisionTally Tally = Existing ? *Existing : GatherCollision();
		const FString Stamp = FDateTime::Now().ToString(TEXT("%Y%m%d_%H%M%S"));
		const FString Path = DebugDir() / FString::Printf(TEXT("CollisionDump_%s.txt"), *Stamp);

		TArray<FString> Lines;
		Lines.Add(FString::Printf(TEXT("When=%s"), *FDateTime::Now().ToString()));
		Lines.Add(FString::Printf(TEXT("Reason=%s"), Reason));
		Lines.Add(FString::Printf(TEXT("World=%s"), *Tally.WorldName));
		Lines.Add(FString::Printf(TEXT("CollisionPrimitives=%d"), Tally.Prim));
		Lines.Add(FString::Printf(TEXT("PersonPrimitives=%d"), Tally.Persons));
		Lines.Add(FString::Printf(TEXT("PlayerPrimitives=%d"), Tally.Players));
		Lines.Add(FString::Printf(TEXT("StreetMapPrimitives=%d"), Tally.Street));
		Lines.Add(FString::Printf(TEXT("Simulating=%d"), Tally.Simulating));
		Lines.Add(FString::Printf(TEXT("QueryOnly=%d"), Tally.QueryOnly));
		Lines.Add(FString::Printf(TEXT("UniqueBodySetups=%d"), Tally.UniqueBodies));
		Lines.Add(FString::Printf(TEXT("UniqueSimpleShapes=%d"), Tally.UniqueSimple));
		Lines.Add(FString::Printf(TEXT("UniqueCapsules=%d"), Tally.UniqueCapsules));
		Lines.Add(FString::Printf(TEXT("UniqueTriMeshes=%d"), Tally.UniqueTriMeshes));
		Lines.Add(FString::Printf(TEXT("Triangles=%lld"), Tally.Triangles));
		Lines.Add(TEXT("TopClasses:"));
		TArray<TPair<FString, int32>> Classes;
		for (const TPair<FString, int32>& Pair : Tally.ByClass)
		{
			Classes.Add(Pair);
		}
		Classes.Sort([](const TPair<FString, int32>& A, const TPair<FString, int32>& B) { return A.Value > B.Value; });
		for (int32 i = 0; i < Classes.Num() && i < 15; ++i)
		{
			const int64 Tris = Tally.TrisByClass.FindRef(Classes[i].Key);
			Lines.Add(FString::Printf(TEXT("  %d %s triangles=%lld"), Classes[i].Value, *Classes[i].Key, Tris));
		}
		Lines.Add(TEXT("OwnersByTriangles:"));
		for (int32 i = 0; i < Tally.Owners.Num() && i < 12; ++i)
		{
			const FCollisionOwner& Owner = Tally.Owners[i];
			Lines.Add(FString::Printf(
				TEXT("  triangles=%lld trimesh=%d simple=%d capsules=%d profile=%s %s %s %s"),
				Owner.Triangles, Owner.TriMeshes, Owner.Simple, Owner.Capsules,
				*Owner.Profile, *Owner.ClassName, *Owner.Actor, *Owner.Component));
		}
		if (Tally.WorldName == TEXT("(aucune)"))
		{
			Lines.Add(TEXT("Note=monde de jeu absent (appeler la commande une fois la partie chargee)"));
		}
		Lines.Add(TEXT("Switch=-LPCollisionLog pour echantillonner apres le chargement, pas au ExecCmds de demarrage"));
		FFileHelper::SaveStringArrayToFile(Lines, *Path);
		UE_LOG(LogLifePlay, Display, TEXT("LPDebug collision : %d primitives, %d trimesh, %lld triangles (%s) -> %s"),
			Tally.Prim, Tally.UniqueTriMeshes, Tally.Triangles, Reason, *Path);
		TRACE_BOOKMARK(TEXT("LP Collision %lld tris"), Tally.Triangles);
		return Path;
	}

	void WriteBookmark(const TArray<FString>& Args)
	{
		const FString Text = Args.Num() > 0 ? FString::Join(Args, TEXT(" ")) : TEXT("manuel");
		UE_LOG(LogLifePlay, Display, TEXT("LPDebug bookmark : %s"), *Text);
		TRACE_BOOKMARK(TEXT("LP %s"), *Text);
	}
}

void ULPDebugSubsystem::Initialize(FSubsystemCollectionBase& Collection)
{
	Super::Initialize(Collection);

	if (!MemSnapshotCommand)
	{
		MemSnapshotCommand = new FAutoConsoleCommand(
			TEXT("LifePlay.MemSnapshot"),
			TEXT("Ecrit Saved/Profiling/LPDebug/MemSnapshot_*.txt et lance memreport."),
			FConsoleCommandDelegate::CreateLambda([]() { WriteMemSnapshot(); }));
		CollisionDumpCommand = new FAutoConsoleCommand(
			TEXT("LifePlay.CollisionDump"),
			TEXT("Ecrit un releve des primitives de collision du monde courant."),
			FConsoleCommandDelegate::CreateLambda([]() { WriteCollisionDump(TEXT("console")); }));
		BookmarkCommand = new FAutoConsoleCommand(
			TEXT("LifePlay.Bookmark"),
			TEXT("Signet Insights (TRACE_BOOKMARK) et ligne LogLifePlay. Argument : texte du signet."),
			FConsoleCommandWithArgsDelegate::CreateStatic(&WriteBookmark));
		HitchSummaryCommand = new FAutoConsoleCommand(
			TEXT("LifePlay.HitchSummary"),
			TEXT("Ecrit le bilan courant des a-coups (-LPHitchLog)."),
			FConsoleCommandDelegate::CreateLambda([]()
			{
				if (ULPDebugSubsystem* Sub = FindDebugSubsystem())
				{
					Sub->LogHitchSummary(TEXT("console"));
				}
				else
				{
					UE_LOG(LogLifePlay, Display, TEXT("LPDebug hitch : sous-systeme absent"));
				}
			}));
		CommandOwner = this;
	}

	bHitchLog = FParse::Param(FCommandLine::Get(), TEXT("LPHitchLog"));
	HitchMs = 50.f;
	FParse::Value(FCommandLine::Get(), TEXT("LPHitchMs="), HitchMs);
	bCollisionLog = FParse::Param(FCommandLine::Get(), TEXT("LPCollisionLog"));
	if (bHitchLog || bCollisionLog)
	{
		StartSeconds = FPlatformTime::Seconds();
		LastFrameSeconds = StartSeconds;
	}
	if (bHitchLog)
	{
		UE_LOG(LogLifePlay, Display, TEXT("LPDebug hitch : actif, seuil %.1f ms"), HitchMs);
	}
	else
	{
		UE_LOG(LogLifePlay, Display, TEXT("LPDebug hitch : inactif"));
	}
	if (bCollisionLog)
	{
		const FString Stamp = FDateTime::Now().ToString(TEXT("%Y%m%d_%H%M%S"));
		CollisionTrackPath = DebugDir() / FString::Printf(TEXT("CollisionTrack_%s.txt"), *Stamp);
		FFileHelper::SaveStringToFile(
			TEXT("t\tworld\tprim\tpersons\tplayers\tstreet\ttrimesh\ttriangles\n"),
			*CollisionTrackPath);
		NextCollisionSeconds = FPlatformTime::Seconds() + 2.0;
		UE_LOG(LogLifePlay, Display, TEXT("LPDebug collision : actif, premier echantillon dans 2 s -> %s"), *CollisionTrackPath);
	}
	else
	{
		UE_LOG(LogLifePlay, Display, TEXT("LPDebug collision : inactif"));
	}
	if (bHitchLog || bCollisionLog)
	{
		FCoreDelegates::OnEndFrame.AddUObject(this, &ULPDebugSubsystem::OnEndFrame);
	}
}

void ULPDebugSubsystem::Deinitialize()
{
	if (bHitchLog)
	{
		LogHitchSummary(TEXT("fin"));
	}
	if (bCollisionLog)
	{
		LogCollisionSummary(TEXT("fin"));
	}
	if (bHitchLog || bCollisionLog)
	{
		FCoreDelegates::OnEndFrame.RemoveAll(this);
	}
	if (CommandOwner == this)
	{
		CommandOwner = nullptr;
	}
	Super::Deinitialize();
}

void ULPDebugSubsystem::OnEndFrame()
{
	const double Now = FPlatformTime::Seconds();
	if (bCollisionLog && Now >= NextCollisionSeconds)
	{
		NextCollisionSeconds = Now + 2.0;
		SampleCollision();
	}
	if (!bHitchLog)
	{
		return;
	}
	const double DeltaMs = (Now - LastFrameSeconds) * 1000.0;
	LastFrameSeconds = Now;
	if (DeltaMs >= HitchMs)
	{
		++HitchCount;
		MaxHitchMs = FMath::Max(MaxHitchMs, DeltaMs);
		if (HitchLines < 100 || (HitchCount % 25) == 0)
		{
			++HitchLines;
			UE_LOG(LogLifePlay, Warning, TEXT("LPDebug hitch : %.1f ms (seuil %.1f) #%d"), DeltaMs, HitchMs, HitchCount);
			TRACE_BOOKMARK(TEXT("LP Hitch %.1f ms"), DeltaMs);
		}
	}

	if (!bLoggedTwoMinuteSummary && (Now - StartSeconds) >= 120.0)
	{
		bLoggedTwoMinuteSummary = true;
		LogHitchSummary(TEXT("2 min"));
	}
}

void ULPDebugSubsystem::LogHitchSummary(const TCHAR* When) const
{
	const double Elapsed = StartSeconds > 0.0 ? FPlatformTime::Seconds() - StartSeconds : 0.0;
	UE_LOG(LogLifePlay, Display, TEXT("LPDebug hitch : %d hitch(s) en %.1f s (seuil %.1f ms), max %.1f ms, %s"),
		HitchCount, Elapsed, HitchMs, MaxHitchMs, When);
}

void ULPDebugSubsystem::SampleCollision()
{
	const FCollisionTally Tally = GatherCollision();
	++CollisionSamples;
	PeakPrim = FMath::Max(PeakPrim, Tally.Prim);
	PeakTriangles = FMath::Max(PeakTriangles, Tally.Triangles);
	const double Elapsed = StartSeconds > 0.0 ? FPlatformTime::Seconds() - StartSeconds : FPlatformTime::Seconds();
	const FString Line = FString::Printf(
		TEXT("%.1f\t%s\t%d\t%d\t%d\t%d\t%d\t%lld\n"),
		Elapsed, *Tally.WorldName, Tally.Prim, Tally.Persons, Tally.Players, Tally.Street,
		Tally.UniqueTriMeshes, Tally.Triangles);
	FFileHelper::SaveStringToFile(Line, *CollisionTrackPath, FFileHelper::EEncodingOptions::AutoDetect, &IFileManager::Get(), FILEWRITE_Append);
	UE_LOG(LogLifePlay, Display, TEXT("LPDebug collision : %.0f s %s prim=%d pnj=%d trimesh=%d triangles=%lld"),
		Elapsed, *Tally.WorldName, Tally.Prim, Tally.Persons, Tally.UniqueTriMeshes, Tally.Triangles);

	const bool bGrew = Tally.Triangles >= LastDumpedTriangles + 1000 || Tally.UniqueTriMeshes > LastDumpedTriMeshes;
	if (CollisionDumps < 4 && Tally.Triangles > 0 && bGrew)
	{
		WriteCollisionDump(TEXT("suivi"), &Tally);
		++CollisionDumps;
		LastDumpedTriangles = Tally.Triangles;
		LastDumpedTriMeshes = Tally.UniqueTriMeshes;
	}
}

void ULPDebugSubsystem::LogCollisionSummary(const TCHAR* When) const
{
	if (CollisionDumps == 0 && PeakPrim > 0)
	{
		WriteCollisionDump(TEXT("fin"));
	}
	UE_LOG(LogLifePlay, Display, TEXT("LPDebug collision : %d echantillon(s), %d dump(s), max %d primitives, %lld triangles, %s"),
		CollisionSamples, CollisionDumps, PeakPrim, PeakTriangles, When);
}

#else

void ULPDebugSubsystem::Initialize(FSubsystemCollectionBase& Collection)
{
	Super::Initialize(Collection);
}

void ULPDebugSubsystem::Deinitialize()
{
	Super::Deinitialize();
}

void ULPDebugSubsystem::OnEndFrame()
{
}

void ULPDebugSubsystem::LogHitchSummary(const TCHAR* When) const
{
	(void)When;
}

void ULPDebugSubsystem::SampleCollision()
{
}

void ULPDebugSubsystem::LogCollisionSummary(const TCHAR* When) const
{
	(void)When;
}

#endif