private ICollection <LandmarkDto> TryGetLandmarksWithinZone(double latitude, double longitude, double distance)
{
ICollection <Landmark> retrieved = landmarks.GetWithinZone(latitude, longitude, distance);
ICollection <LandmarkDto> dtos = GetLandmarkDtos(retrieved);
return(dtos);
}
public async Task <bool> NotifyIfCloseToLandmark(string token, double lat, double lng)
{
DateTime time;
if (!tokenCache.TryGetValue(token, out time))
{
//500 m distance, get first landmark.
ICollection <Landmark> closeLandmarks = landmarks.GetWithinZone(lat, lng, proximityDistance, 0, 1);
if (closeLandmarks.Any())
{
Landmark toSend = closeLandmarks.First();
SendPushNotification(token, toSend, ComputeDistanceMeters(lat, lng, toSend.Latitude, toSend.Longitude));
tokenCache.Set(token, DateTime.Now, DateTimeOffset.UtcNow.AddHours(intervalBetweenNotifications));
return(true);
}
}
return(false);
}