FloorDatetimeToDayPrecision.cs

private DateTime? FloorDatetimeToDayPrecision(DateTime? inDatetime)
{
    if (inDatetime.HasValue && inDatetime.Value.TimeOfDay > TimeSpan.MinValue)
    {
        var oldDatetime = inDatetime.Value;
        return new DateTime(oldDatetime.Year, oldDatetime.Month, oldDatetime.Day, 0, 0, 0);
    }
    else
    {
        return inDatetime;
    }
}