-(void)startNextRouteTask {
    if(nil == self.currentBuilding){
        NSLog(@"ERROR: building not loaded!");
        return;
    }

    static BOOL isBusy = NO;
    static dispatch_queue_t backgroundQueue = nil;
    if(nil == backgroundQueue){
        backgroundQueue = dispatch_queue_create("com.messe.abindooradkmanager.route", 0);
    }

    NSArray *waitObservers = [self.routingQueue allKeys];
    if(NO == isBusy && waitObservers.count > 0){
        isBusy = YES;

        NSValue *observerValue = waitObservers.firstObject;
        NSMutableArray *tasks = [self.routingQueue objectForKey:observerValue];
        ABPair *routeTask = tasks.firstObject;

        self.currentRouteTaskObserver = observerValue.nonretainedObjectValue;
        NSValue* start = routeTask.a;
        NSValue* end = routeTask.b;

        IDSFloor *floor = [self.currentBuilding floorAtLevel:0];

        static CGPoint startP;
        static CGPoint endP;
        startP = start.CGPointValue;
        endP = end.CGPointValue;
        //convert to indor coords
        startP = [self indoorCoordsForGeoLocation:CLLocationCoordinate2DMake(startP.x, startP.y)  inBuilding:self.currentBuilding andFloor:floor];
        endP = [self indoorCoordsForGeoLocation:CLLocationCoordinate2DMake(endP.x, endP.y) inBuilding:self.currentBuilding andFloor:floor];

        [tasks removeObject:routeTask];
        if(0 == tasks.count){
            [self.routingQueue removeObjectForKey:observerValue];
        }

        dispatch_async(backgroundQueue, ^{
            NSLog(@"%@",NSStringFromCGPoint(startP));
            NSLog(@"%@",NSStringFromCGPoint(endP));
            IDSCoordinate* startC = [[IDSCoordinate alloc] initWithX:startP.x andY:startP.y andFloorLevel:0] ;
            IDSCoordinate* endC = [[IDSCoordinate alloc] initWithX:endP.x andY:endP.y andFloorLevel:0] ;

            @try {
                NSLog(@"-START-");
                [[Indoors instance] routeFromLocation:startC toLocation:endC delegate:self];
                NSLog(@"-END-");
            }
            @catch (NSException *exception) {
                NSLog(@"-ERROR- %@", exception);
            }
            @finally {

            }

            [startC release];
            [endC release];

            dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
                isBusy = NO;
                [self performSelectorOnMainThread:@selector(startNextRouteTask) withObject:nil waitUntilDone:NO];
            });
        });
    }
}