protected override IEnumerable <Datum> Poll(CancellationToken cancellationToken)
{
List <Datum> data = new List <Datum>();
Position currentPosition = GpsReceiver.Get().GetReading(cancellationToken);
if (currentPosition != null)
{
foreach (PointOfInterest pointOfInterest in SensusServiceHelper.Get().PointsOfInterest.Union(Protocol.PointsOfInterest)) // POIs are stored on the service helper (e.g., home locations) and the Protocol (e.g., bars), since the former are user-specific and the latter are universal.
{
double distanceToPointOfInterestMeters = pointOfInterest.KmDistanceTo(currentPosition) * 1000;
foreach (PointOfInterestProximityTrigger trigger in _triggers)
{
if (pointOfInterest.Triggers(trigger, distanceToPointOfInterestMeters))
{
data.Add(new PointOfInterestProximityDatum(currentPosition.Timestamp, pointOfInterest, distanceToPointOfInterestMeters, trigger));
}
}
}
}
if (data.Count == 0)
{
data.Add(null);
}
return(data);
}
protected override void Initialize()
{
base.Initialize();
if (!GpsReceiver.Get().Locator.IsGeolocationEnabled)
{
string error = "Geolocation is not enabled on this device. Cannot start location probe.";
SensusServiceHelper.Get().FlashNotificationAsync(error);
throw new Exception(error);
}
}
protected override void Initialize()
{
base.Initialize();
if (!GpsReceiver.Get().Locator.IsGeolocationEnabled)
{
// throw standard exception instead of NotSupportedException, since the user might decide to enable GPS in the future
// and we'd like the probe to be restarted at that time.
string error = "Geolocation is not enabled on this device. Cannot start location probe.";
SensusServiceHelper.Get().FlashNotificationAsync(error);
throw new Exception(error);
}
}
protected sealed override IEnumerable <Datum> Poll(CancellationToken cancellationToken)
{
Position reading = GpsReceiver.Get().GetReading(cancellationToken);
if (reading == null)
{
return new Datum[] { }
}
;
else
{
return new Datum[] { new LocationDatum(reading.Timestamp, reading.Accuracy, reading.Latitude, reading.Longitude) }
};
}
}
public PointOfInterestProximityTrigger(string pointOfInterestName, string pointOfInterestType, double distanceThresholdMeters, ProximityThresholdDirection distanceThresholdDirection)
: this()
{
if (string.IsNullOrWhiteSpace(pointOfInterestName) && string.IsNullOrWhiteSpace(pointOfInterestType))
{
throw new Exception("No POI was supplied.");
}
else if (distanceThresholdMeters <= 0)
{
throw new Exception("Invalid distance threshold. Must be greater than zero.");
}
else if (distanceThresholdMeters < GpsReceiver.Get().MinimumDistanceThreshold)
{
throw new Exception("Distance threshold must be at least " + GpsReceiver.Get().MinimumDistanceThreshold + ".");
}
_pointOfInterestName = pointOfInterestName;
_pointOfInterestType = pointOfInterestType;
_distanceThresholdMeters = distanceThresholdMeters;
_distanceThresholdDirection = distanceThresholdDirection;
}
protected sealed override void StopListening()
{
GpsReceiver.Get().RemoveListener(_positionChangedHandler);
}
protected sealed override void StartListening()
{
GpsReceiver.Get().AddListener(_positionChangedHandler);
}