public FitDecoder(Stream stream, Dynastream.Fit.File fileType)
{
inputStream = stream;
this.fileType = fileType;
Messages = new FitMessages();
}
public static void MergeHeartRates(FitMessages messages)
{
float? hr_anchor_event_timestamp = 0.0f;
DateTime hr_anchor_timestamp = new DateTime(0);
bool hr_anchor_set = false;
byte? last_valid_hr = 0;
DateTime last_valid_hr_time = new DateTime(0);
DateTime record_range_start_time = new DateTime(messages.Records[0].GetTimestamp());
int hr_start_index = 0;
int hr_start_sub_index = 0;
//
// Update this foreach() to loop through just the Record messages
//
foreach (RecordMesg recordMesg in messages.Records)
{
long hrSum = 0;
long hrSumCount = 0;
// Obtain the time for which the record message is valid
DateTime record_range_end_time = new DateTime(recordMesg.GetTimestamp());
// Need to determine timestamp range which applies to this record
bool findingInRangeHrMesgs = true;
// Start searching HR mesgs where we left off
int hr_mesg_counter = hr_start_index;
int hr_sub_mesg_counter = hr_start_sub_index;
//
// Update this while() to loop through just the HR messages
//
while (findingInRangeHrMesgs && (hr_mesg_counter < messages.HeartRates.Count))
{
HrMesg hrMesg = new HrMesg(messages.HeartRates[hr_mesg_counter]);
// Update HR timestamp anchor, if present
if (hrMesg.GetTimestamp() != null && hrMesg.GetTimestamp().GetTimeStamp() != 0)
{
hr_anchor_timestamp = new DateTime(hrMesg.GetTimestamp());
hr_anchor_set = true;
if (hrMesg.GetFractionalTimestamp() != null)
{
hr_anchor_timestamp.Add((double)hrMesg.GetFractionalTimestamp());
}
if (hrMesg.GetNumEventTimestamp() == 1)
{
hr_anchor_event_timestamp = hrMesg.GetEventTimestamp(0);
}
else
{
throw new FitException("FIT HrToRecordMesgBroadcastPlugin Error: Anchor HR mesg must have 1 event_timestamp");
}
}
if (hr_anchor_set == false)
{
// We cannot process any HR messages if we have not received a timestamp anchor
throw new FitException("FIT HrToRecordMesgBroadcastPlugin Error: No anchor timestamp received in a HR mesg before diff HR mesgs");
}
else if (hrMesg.GetNumEventTimestamp() != hrMesg.GetNumFilteredBpm())
{
throw new FitException("FIT HrToRecordMesgBroadcastPlugin Error: HR mesg with mismatching event timestamp and filtered bpm");
}
for (int j = hr_sub_mesg_counter; j < hrMesg.GetNumEventTimestamp(); j++)
{
// Build up timestamp for each message using the anchor and event_timestamp
DateTime hrMesgTime = new DateTime(hr_anchor_timestamp);
float? event_timestamp = hrMesg.GetEventTimestamp(j);
// Deal with roll over case
if (event_timestamp < hr_anchor_event_timestamp)
{
if ((hr_anchor_event_timestamp - event_timestamp) > (1 << 21))
{
event_timestamp += (1 << 22);
}
else
{
throw new FitException("FIT HrToRecordMesgBroadcastPlugin Error: Anchor event_timestamp is greater than subsequent event_timestamp. This does not allow for correct delta calculation.");
}
}
hrMesgTime.Add((double)(event_timestamp - hr_anchor_event_timestamp));
// Check if hrMesgTime is gt record start time
// and if hrMesgTime is lte to record end time
if ((hrMesgTime.CompareTo(record_range_start_time) > 0) &&
(hrMesgTime.CompareTo(record_range_end_time) <= 0))
{
hrSum += (long)hrMesg.GetFilteredBpm(j);
hrSumCount++;
last_valid_hr_time = new DateTime(hrMesgTime);
}
// check if hrMesgTime exceeds the record time
else if (hrMesgTime.CompareTo(record_range_end_time) > 0)
{
// Remember where we left off
hr_start_index = hr_mesg_counter;
hr_start_sub_index = j;
findingInRangeHrMesgs = false;
if (hrSumCount > 0)
{
// Update record heart rate
last_valid_hr = (byte?)System.Math.Round((((float)hrSum) / hrSumCount), System.MidpointRounding.AwayFromZero);
recordMesg.SetHeartRate(last_valid_hr);
messages.RecordFieldNames.Add("HeartRate");
}
// If no stored HR is available, fill in record messages with the
// last valid filtered hr for a maximum of 5 seconds
else if ((record_range_start_time.CompareTo(last_valid_hr_time) > 0) &&
((record_range_start_time.GetTimeStamp() - last_valid_hr_time.GetTimeStamp()) < 5))
{
recordMesg.SetHeartRate(last_valid_hr);
messages.RecordFieldNames.Add("HeartRate");
}
// Reset HR average
hrSum = 0;
hrSumCount = 0;
record_range_start_time = new DateTime(record_range_end_time);
// Breaks out of looping within the event_timestamp array
break;
}
}
hr_mesg_counter++;
hr_sub_mesg_counter = 0;
}
}
}
public ActivityParser(FitMessages messages)
{
_messages = messages;
}
