/// <summary>
/// Perform actions based on current status and prediction.
/// </summary>
/// <param name="prediction"></param>
private void DispatchPrediction(PredictionArgs prediction)
{
if (prediction == null)
{
Debug.WriteLine("DISPATCH: null prediction");
// do nothing
return;
}
lock (_lockStatus)
{
if (ServiceState == ServiceStateCode.Idle || ServiceState == ServiceStateCode.Training)
{
Debug.WriteLine("DISPATCH: skip state " + ServiceState.ToString());
// do nothing
return;
}
// update prediction counter
var previousCounter = ConsecutiveCorrectPredictions;
var currentCounter = (prediction.Success ? previousCounter + 1 : 0);
ConsecutiveCorrectPredictions = currentCounter;
if (
(previousCounter >= NotificationThreshold && currentCounter == 0) ||
(previousCounter < NotificationThreshold && currentCounter == NotificationThreshold))
{
Debug.WriteLine("DISPATCH: prediction threshold passed");
// notify all subscribers about prediction
var contextId =
prediction.PredictedScenario == null
? null : prediction.PredictedScenario.ContextId.ToString();
DoReportPrediction(contextId);
}
if (ServiceState == ServiceStateCode.Tracking)
{
if (prediction.Success)
{
Debug.WriteLine("DISPATCH: success in tracking state.");
// no need to track
_tracker.Enabled = false;
}
else
{
Debug.WriteLine("DISPATCH: failure in tracking state.");
// training needed
_tracker.ScenarioId =
prediction.PredictedScenario == null
? null : prediction.PredictedScenario.Id.ToString();
_tracker.Enabled = true;
}
}
}
}
/// <summary>
/// Try to find a scenario for the target context. On failure, a new
/// scenario is created if the creation is allowed, otherwise the
/// predicted scenario is returned.
/// </summary>
/// <returns>A prediction, or null in case of error.</returns>
public PredictionArgs Prediction()
{
Context context = null;
PredictionArgs prediction = null;
lock (_localizerLock)
{
if (ContextId != null)
{
try
{
context = _contextService.GetById(ContextId);
if (context == null)
{
// notify error
if (LocalizerErrorNotification != null)
{
var args = new LocalizerErrorNotificationEventArgs(
LocalizerErrorNotificationCode.UnknownContext);
ThreadPool.QueueUserWorkItem(new WaitCallback(DoNotification), args);
}
}
}
catch (Exception ex)
{
if (LocalizerErrorNotification != null)
{
// notify error
var args = new LocalizerErrorNotificationEventArgs(
LocalizerErrorNotificationCode.DatabaseError, ex);
ThreadPool.QueueUserWorkItem(new WaitCallback(DoNotification), args);
}
}
}
if (context != null)
{
// context found in the database
prediction = new PredictionArgs
{
Success = false
};
IEnumerable <ContextPreference> pref = null;
for (var attempts = this.Retries + 1; attempts > 0; attempts--)
{
prediction.PredictedScenario = GetScenarioForCurrentPosition(out pref);
if (prediction.PredictedScenario == null)
{
// retry, eventually..
continue;
}
if (ContextId.Equals(prediction.PredictedScenario.ContextId.ToString()))
{
// correct prediction
_scenarioService.IncreaseAccuracy(prediction.PredictedScenario);
prediction.Success = true;
break;
}
// wrong prediction
_scenarioService.DecreaseAccuracy(prediction.PredictedScenario);
}
if (!prediction.Success && CreationAllowed)
{
// create a new scenario for the requested context
prediction.PredictedScenario = new Scenario
{
ContextId = new ObjectId(ContextId),
CreationTime = DateTime.Now
};
try
{
_scenarioService.Create(prediction.PredictedScenario);
}
catch (Exception ex)
{
if (LocalizerErrorNotification != null)
{
// notify error
var args = new LocalizerErrorNotificationEventArgs(
LocalizerErrorNotificationCode.DatabaseError, ex);
ThreadPool.QueueUserWorkItem(new WaitCallback(DoNotification), args);
}
prediction = null;
}
}
} // end if(context != null)
} // unlock
return(prediction);
}