private static Task <IEnumerable <Measurement> > GetFittedMeasurements(
DataConnection Connection, int SensorId, DateTime StartTime, DateTime EndTime,
int MaxMeasurementCount)
{
if (EndTime < StartTime)
{
throw new ArgumentException($"{nameof(StartTime)} was greater than {nameof(EndTime)}");
}
var timeSpan = EndTime - StartTime;
if (timeSpan.TotalMinutes <= MaxMeasurementCount)
{
// Assume that one measurement was made per minute.
// This assumption may not _always_ prove to be correct,
// but we'd like to keep database chatter to a minimum.
return(Connection.GetMeasurementsAsync(SensorId, StartTime, EndTime));
}
else if (timeSpan.TotalHours <= MaxMeasurementCount)
{
return(Connection.GetHourAveragesAsync(
SensorId, MeasurementAggregation.Quantize(StartTime, TimeSpan.FromHours(1)),
(int)Math.Round(timeSpan.TotalHours)));
}
else if (timeSpan.TotalDays <= MaxMeasurementCount)
{
return(Connection.GetDayAveragesAsync(
SensorId, MeasurementAggregation.Quantize(StartTime, TimeSpan.FromDays(1)),
(int)Math.Round(timeSpan.TotalDays)));
}
else
{
int yearCount = EndTime.Year - StartTime.Year;
int monthCount = 12 * yearCount + EndTime.Month - StartTime.Month;
if (monthCount <= MaxMeasurementCount)
{
return(Connection.GetMonthAveragesAsync(
SensorId, MeasurementAggregation.QuantizeMonth(StartTime), monthCount));
}
else
{
return(Connection.GetYearAveragesAsync(
SensorId, MeasurementAggregation.QuantizeYear(StartTime), yearCount));
}
}
}
/// <summary>
/// Quantizes the given date-time.
/// </summary>
public override DateTime Quantize(DateTime Time)
{
return(MeasurementAggregation.QuantizeYear(Time));
}