#include "ZMMOAttributeNetworkHandler.h"

#include "Engine/GameInstance.h"
#include "Engine/World.h"
#include "EngineUtils.h"  // TActorIterator
#include "GameFramework/Actor.h"
#include "ZMMOAttributeComponent.h"
#include "ZMMOAttributeTypes.h"
#include "ZeusNetworkSubsystem.h"

namespace
{
	// Helper privado — converte o payload binario do plugin pra USTRUCT
	// Blueprint que o componente exibe.
	FZMMOAttributesSnapshot ToSnapshot(const FZeusAttributesPayload& P)
	{
		FZMMOAttributesSnapshot S;
		S.EntityId    = P.EntityId;
		S.ClassId     = P.ClassId;
		S.BaseLevel   = P.BaseLevel;
		S.BaseExp     = P.BaseExp;
		S.JobLevel    = P.JobLevel;
		S.JobExp      = P.JobExp;
		S.Str         = P.Str;
		S.Agi         = P.Agi;
		S.Vit         = P.Vit;
		S.Int         = P.Int;
		S.Dex         = P.Dex;
		S.Luk         = P.Luk;
		S.StatusPoint = P.StatusPoint;
		S.SkillPoint  = P.SkillPoint;
		S.Hp          = P.Hp;
		S.MaxHp       = P.MaxHp;
		S.Sp          = P.Sp;
		S.MaxSp       = P.MaxSp;
		S.Money       = P.Money;
		S.Atk         = P.Atk;
		S.Matk        = P.Matk;
		S.Def         = P.Def;
		S.Mdef        = P.Mdef;
		S.Hit         = P.Hit;
		S.Flee        = P.Flee;
		S.CritX10     = P.CritX10;
		S.Aspd        = P.Aspd;
		return S;
	}

	// V1 — resolve por EntityId varrendo atores do mundo procurando um que
	// tenha `UZMMOAttributeComponent`. Funciona para PIE com 1-2 players +
	// proxies. Otimizacao futura: usar `UZMMOWorldSubsystem::GetActorByEntityId`
	// (precisa expor) ou cache local de `EntityId -> UAttributeComponent*`.
	//
	// Convencao: `IZMMOEntityInterface::GetZMMOEntityId()` retorna o EntityId
	// autoritativo do servidor. Nao depender da interface aqui para manter
	// ZMMOAttributes sem `#include` do modulo ZMMO core — varremos `Tags`
	// alternativamente, mas o caminho mais simples e' a propria component
	// keys de `EntityId` no proprio componente (TODO Fase 2: armazenar
	// EntityId no componente quando snapshot chega).
	UZMMOAttributeComponent* FindComponentForEntity(UWorld* World, int32 EntityId)
	{
		if (!World || EntityId == 0) { return nullptr; }
		for (TActorIterator<AActor> It(World); It; ++It)
		{
			AActor* Actor = *It;
			if (!Actor) { continue; }
			UZMMOAttributeComponent* Comp = Actor->FindComponentByClass<UZMMOAttributeComponent>();
			if (!Comp) { continue; }
			if (Comp->GetSnapshot().EntityId == EntityId)
			{
				return Comp;
			}
		}
		return nullptr;
	}
}

bool UZMMOAttributeNetworkHandler::ShouldCreateSubsystem(UObject* Outer) const
{
	// Cria apenas para mundos de gameplay (PIE/Game), nao para editor preview.
	UWorld* World = Cast<UWorld>(Outer);
	if (!World) { return false; }
	return World->WorldType == EWorldType::Game || World->WorldType == EWorldType::PIE;
}

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

	if (UZeusNetworkSubsystem* Net = GetZeusNetSubsystem())
	{
		SnapshotFullHandle = Net->OnAttributeSnapshotFull.AddUObject(
			this, &UZMMOAttributeNetworkHandler::HandleAttributeSnapshotFull);
		HpSpUpdateHandle = Net->OnHpSpUpdate.AddUObject(
			this, &UZMMOAttributeNetworkHandler::HandleHpSpUpdate);
		LevelUpHandle = Net->OnLevelUp.AddUObject(
			this, &UZMMOAttributeNetworkHandler::HandleLevelUp);
	}
}

void UZMMOAttributeNetworkHandler::Deinitialize()
{
	if (UZeusNetworkSubsystem* Net = GetZeusNetSubsystem())
	{
		if (SnapshotFullHandle.IsValid())
		{
			Net->OnAttributeSnapshotFull.Remove(SnapshotFullHandle);
			SnapshotFullHandle.Reset();
		}
		if (HpSpUpdateHandle.IsValid())
		{
			Net->OnHpSpUpdate.Remove(HpSpUpdateHandle);
			HpSpUpdateHandle.Reset();
		}
		if (LevelUpHandle.IsValid())
		{
			Net->OnLevelUp.Remove(LevelUpHandle);
			LevelUpHandle.Reset();
		}
	}
	Super::Deinitialize();
}

UZeusNetworkSubsystem* UZMMOAttributeNetworkHandler::GetZeusNetSubsystem() const
{
	const UWorld* World = GetWorld();
	if (!World) { return nullptr; }
	UGameInstance* GI = World->GetGameInstance();
	if (!GI) { return nullptr; }
	return GI->GetSubsystem<UZeusNetworkSubsystem>();
}

void UZMMOAttributeNetworkHandler::HandleAttributeSnapshotFull(const FZeusAttributesPayload& Payload)
{
	UWorld* World = GetWorld();
	if (!World) { return; }
	UZMMOAttributeComponent* Comp = FindComponentForEntity(World, Payload.EntityId);
	if (!Comp)
	{
		// V1 fallback: aplica ao primeiro UZMMOAttributeComponent encontrado
		// (player local). Isso resolve o caso do primeiro snapshot chegar
		// antes do `EntityId` estar registrado no componente (que so' acontece
		// apos o primeiro snapshot — chicken-and-egg). Apos o primeiro apply,
		// `Current.EntityId` ja' bate e o caminho normal funciona.
		for (TActorIterator<AActor> It(World); It; ++It)
		{
			AActor* Actor = *It;
			if (!Actor) { continue; }
			Comp = Actor->FindComponentByClass<UZMMOAttributeComponent>();
			if (Comp && Comp->GetSnapshot().EntityId == 0)
			{
				break;
			}
			Comp = nullptr;
		}
	}
	if (Comp)
	{
		Comp->ApplySnapshot(ToSnapshot(Payload));
	}
}

void UZMMOAttributeNetworkHandler::HandleHpSpUpdate(int32 EntityId, int32 Hp, int32 Sp)
{
	UWorld* World = GetWorld();
	if (!World) { return; }
	UZMMOAttributeComponent* Comp = FindComponentForEntity(World, EntityId);
	if (Comp)
	{
		Comp->ApplyHpSpUpdate(Hp, Sp);
	}
}

void UZMMOAttributeNetworkHandler::HandleLevelUp(int32 EntityId, int32 NewBaseLevel, int32 StatusPointDelta)
{
	UWorld* World = GetWorld();
	if (!World) { return; }
	UZMMOAttributeComponent* Comp = FindComponentForEntity(World, EntityId);
	if (Comp)
	{
		Comp->NotifyLevelUp(NewBaseLevel, StatusPointDelta);
	}
}