blaster/Source/Blaster/Components/LagCompensationComponent.h

// Fill out your copyright notice in the Description page of Project Settings.

#pragma once

#include "CoreMinimal.h"
#include "Blaster/Character/BlasterCharacter.h"
#include "Components/ActorComponent.h"
#include "LagCompensationComponent.generated.h"

USTRUCT(BlueprintType)
struct FBoxInformation
{
	GENERATED_BODY()

	UPROPERTY()
	FVector Location;

	UPROPERTY()
	FRotator Rotation;

	UPROPERTY()
	FVector BoxExtent;
};

USTRUCT(BlueprintType)
struct FFramePackage
{
	GENERATED_BODY()

	UPROPERTY()
	float Time;

	UPROPERTY()
	TMap<FName, FBoxInformation> HitBoxInfo;

	UPROPERTY()
	ABlasterCharacter* Character;
};

USTRUCT(BlueprintType)
struct FServerSideRewindResult
{
	GENERATED_BODY()

	UPROPERTY()
	bool bHitConfirmed;

	UPROPERTY()
	bool bHeadShot;
};

USTRUCT(BlueprintType)
struct FShotgunServerSideRewindResult
{
	GENERATED_BODY()

	UPROPERTY()
	TMap<ABlasterCharacter*, uint32> Headshots;

	UPROPERTY()
	TMap<ABlasterCharacter*, uint32> BodyShots;
};

UCLASS(ClassGroup=(Custom), meta=(BlueprintSpawnableComponent))
class BLASTER_API ULagCompensationComponent : public UActorComponent
{
	GENERATED_BODY()

public:
	ULagCompensationComponent();
	friend ABlasterCharacter;
	virtual void TickComponent(float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction) override;
	void ShowFramePackage(const FFramePackage& Package, const FColor Color);

	// Hitscan
	FServerSideRewindResult ServerSideRewind(
		ABlasterCharacter* HitCharacter,
		const FVector_NetQuantize& TraceStart,
		const FVector_NetQuantize& HitLocation,
		float HitTime
	);

	// Projectiles
	FServerSideRewindResult ProjectileServerSideRewind(
		ABlasterCharacter* HitCharacter,
		const FVector_NetQuantize& TraceStart,
		const FVector_NetQuantize100& InitialVelocity,
		float HitTime
	);

	// Shotgun
	UFUNCTION(Server, Reliable)
	void ShotgunServerScoreRequest(
		const TArray<ABlasterCharacter*>& HitCharacters,
		const FVector_NetQuantize& TraceStart,
		const TArray<FVector_NetQuantize>& HitLocations,
		float HitTime
	);

	UFUNCTION(Server, Reliable)
	void ServerScoreRequest(
		ABlasterCharacter* HitCharacter,
		const FVector_NetQuantize& TraceStart,
		const FVector_NetQuantize& HitLocation,
		float HitTime,
		AWeapon* DamageCauser
	);

	UFUNCTION(Server, Reliable)
	void ProjectileServerScoreRequest(
		ABlasterCharacter* HitCharacter,
		const FVector_NetQuantize& TraceStart,
		const FVector_NetQuantize100& InitialVelocity,
		float HitTime
	);

	FShotgunServerSideRewindResult ShotgunServerSideRewind(
		const TArray<ABlasterCharacter*>& HitCharacters,
		const FVector_NetQuantize& TraceStart,
		const TArray<FVector_NetQuantize>& HitLocations,
		float HitTime
	);

protected:
	void SaveFramePackage();
	void SaveFramePackage(FFramePackage& Package);
	FFramePackage InterpBetweenFrames(const FFramePackage& OlderFrame, const FFramePackage& YoungerFrame, float HitTime);

	void CacheBoxPositions(ABlasterCharacter* HitCharacter, FFramePackage& OutFramePackage);
	void MoveBoxes(ABlasterCharacter* HitCharacter, const FFramePackage& Package);
	void ResetHitBoxes(ABlasterCharacter* HitCharacter, const FFramePackage& Package);
	void EnableCharacterMeshCollision(ABlasterCharacter* HitCharacter, ECollisionEnabled::Type CollisionEnabled);
	FFramePackage GetFrameToCheck(ABlasterCharacter* HitCharacter, float HitTime);

	// Hitscan
	FServerSideRewindResult ConfirmHit(
		const FFramePackage& Package,
		ABlasterCharacter* HitCharacter,
		const FVector_NetQuantize& TraceStart,
		const FVector_NetQuantize HitLocation
	);

	// Projectile
	FServerSideRewindResult ProjectileConfirmHit(
		const FFramePackage& Package,
		ABlasterCharacter* HitCharacter,
		const FVector_NetQuantize& TraceStart,
		const FVector_NetQuantize100& InitialVelocity,
		float HitTime
	);

	// Shotgun
	FShotgunServerSideRewindResult ShotgunConfirmHit(
		const TArray<FFramePackage>& FramePackages,
		const FVector_NetQuantize& TraceStart,
		const TArray<FVector_NetQuantize>& HitLocations
	);

private:
	UPROPERTY()
	ABlasterCharacter* Character;

	UPROPERTY()
	ABlasterPlayerController* Controller;

	TDoubleLinkedList<FFramePackage> FrameHistory;

	UPROPERTY(EditAnywhere)
	float MaxRecordTime = 4.f;
};