UPROPERTY(VisibleAnywhere,Category = "Input")
TObjectPtr<USplineComponent> Spline;
//是否在自動尋路
bool bAutoRunning = false;
//鼠標已按住時間
float FollowTime = 0.f;
//鼠標按住時間
UPROPERTY(EditAnywhere)
float HoldTimeToMove = 0.5f;
//到目的地距離
UPROPERTY(EditAnywhere)
float AutoRunningAcceptRadius = 50.f;
//目的地
FVector CachedDestination = FVector::Zero();

void ADiabloPlayerController::AbilityInputTagPressed()
{
    bAutoRunning = false;
}

void ADiabloPlayerController::AbilityInputTagReleased()
{
        APawn* ControlledPawn = GetPawn();
        if (FollowTime < HoldTimeToMove && ControlledPawn)
        {
            //尋蹤玩家到目的地的路徑
            if (UNavigationPath* Path = UNavigationSystemV1::FindPathToLocationSynchronously(this,ControlledPawn->GetActorLocation(),CachedDestination))
            {
                Spline->ClearSplinePoints();
                //路徑上的點
                TArray<FVector> Points = Path->PathPoints;
                if (!Points.IsEmpty())
                {
                    for (FVector PathPoint : Points)
                    {
                        //在樣條線上加點
                        Spline->AddSplinePoint(PathPoint,ESplineCoordinateSpace::World);
                        DrawDebugSphere(GetWorld(),PathPoint,8.f,8,FColor::Green,false,5.f);
                    }
                    //最后點算做目的地
                    CachedDestination = Points.Last();
                    bAutoRunning = true;
                }
            }
        }
        FollowTime = 0;
}

void ADiabloPlayerController::AbilityInputTagHeld()
{
        //按住時間累積
        FollowTime += GetWorld()->GetDeltaSeconds();
        //得到點擊的目的地
        FHitResult HitResult;
        if (GetHitResultUnderCursor(ECC_Visibility,false,HitResult))
        {
            CachedDestination = HitResult.ImpactPoint;
        }
        APawn* ControlledPawn = GetPawn();
        if (ControlledPawn)
        {
            //移動到目的地
            FVector Direction = CachedDestination - ControlledPawn->GetActorLocation();
            ControlledPawn->AddMovementInput(Direction);
        }
}

void ADiabloPlayerController::AutoRun()
{
    if (!bAutoRunning)
    {
        return;
    }
     APawn* CharacterPawn = GetPawn();
    if (CharacterPawn)
    {
        //找到玩家到樣條線最近的點
        FVector LocationOnSpline = Spline->FindLocationClosestToWorldLocation(CharacterPawn->GetActorLocation(),ESplineCoordinateSpace::World);
        //獲得樣條線上該點的朝向
        FVector Direction = Spline->FindDirectionClosestToWorldLocation(LocationOnSpline,ESplineCoordinateSpace::World);
        CharacterPawn->AddMovementInput(Direction);
        //計算到目的地距離
        float Distance = (LocationOnSpline - CachedDestination).Length();
        //到達目的地則停止尋路
        if (Distance<= AutoRunningAcceptRadius)
        {
            bAutoRunning = false;
        }
    }
}