LTrackSearch usage

final class AGMHumpRoute
{
    // Either TrackNumber
    public int TrackNumber = -1;
    public int MarkerId;

    // Or Junction LEFT RIGHT
    public int JnId = -1;
    public AGMHumpRoute LEFT;
    public AGMHumpRoute RIGHT;
};

    define int StateScan = 0;
    define int StateJnLeft = 1;
    define int StateJnRight = 2;
    define int StateBack = 3;
    define int StateDone = 4;

    final AGMHumpRouteScanResult Scan()
    {
        AGMHumpRoute node;
        LTrackSearch it = new LTrackSearch().DistanceLimit(400000.0f)
                                            .SleepAfter(1000)
                                            .DepthLimit(20)
                                            .DetectCycles(true, true)
                                            .FromTrackside(Owner, LTrackSearch.FORWARD, StateScan);
        while (true) {
            Log("S: "+it.State());
            switch (it.State()) {
                case StateScan: {
                    if (it.MoveNextTrackside()) {
                        Log("obj: "+it.CurrentTrackside().GetLocalisedName());
                        AGMHumpTrackMarker marker = cast <AGMHumpTrackMarker> it.CurrentTrackside();
                        if (marker and marker.HumpTrack >= 0) {
                            Log("mrk: "+marker.GetLocalisedName());
                            if (marker.HumpTrack > 0) {
                                node = new AGMHumpRoute();
                                node.TrackNumber = marker.HumpTrack;
                                node.MarkerId = marker.GetId();
                            }
                            it.SetState(StateBack);
                        }
                        else if (it.CurrentJunction()) {
                            int dir = it.GetArrivedDirection();
                            Log("jn: '"+it.CurrentJunction().GetLocalisedName()+"', dir " + dir);
                            if  (dir == LTrackSearch.BACKWARD) {
                                node = new AGMHumpRoute();
                                node.JnId = it.CurrentJunction().GetId();
                                it.SetState(StateJnLeft, (object)node);
                                node = null;
                                it.PushState(StateScan);
                                it.SetDirection(LTrackSearch.LEFT);
                            }
                        }
                    }
                    else
                        it.SetState(StateBack);
                    continue;
                }
                case StateJnLeft: {
                    AGMHumpRoute parent = cast <AGMHumpRoute> it.StateData();
                    parent.LEFT = node;
                    node = null;
                    it.SetState(StateJnRight);
                    it.PushState(StateScan);
                    it.SetDirection(LTrackSearch.RIGHT);
                    continue;
                }
                case StateJnRight: {
                    AGMHumpRoute parent = cast <AGMHumpRoute> it.StateData();
                    parent.RIGHT = node;
                    node = parent;
                    it.SetState(StateBack);
                    continue;
                }
                case StateBack: {
                    if (it.IsEmpty())
                        break;
                    it.PopState();
                    continue;
                }
                default: break;
            }
            break;
        }

        AGMHumpRouteScanResult ret = new AGMHumpRouteScanResult();
        LTrackSearchStatus status = it.Status();
        ret.Root = node;
        ret.Overflow = status.Overflow;
        ret.BadJunctionIds = status.BadJunctionIds;
        ret.CyclicJunctionIds = status.CyclicJunctionIds;
        return ret;
    }