This is significant now because it will allow accurate recording of
multiple simultaneous connections.
This is important for the future because it establishes the
necessary infrastructure for recording downloaded sessions into their
own files so that they can be saved as backups.
Calling openConnection will return an open connection or nullptr.
Deleting the connection will close it.
SerialPort now uses this under the hood, while still presenting
the QSerialPort-compatible interface.
DreamStation ramp time and mask resistance "off" settings are now also imported.
Ventilator alarms are not yet parsed reliably enough to import at this time.
Previously it was reporting spurious information when the humidifier was
disconnected. Now it only reports settings details when the humidifier is
connected (the only time they're valid.)
It also now reports the humidification mode (fixed, adaptive, or heated
tube), and the heated tube temperature when appropriate.
The last statistics events in each slice are now correctly imported.
Previously, in the surprising edge case where two statistic periods are
reported with the same end-of-slice timestamp, they were both being duplicated
when marking the end of the slice.
Also, there were scattered instances where the final statistics in a slice
weren't being imported at all or were being imported incorrectly. These are
now fixed as well.
If there are no mask-on slices of nonzero duration, then there's not any
meaningful event or waveform data for the session. There is occasionally some
fragmentary data, but it's always less than 1 second.
When such fragmentary waveform data is present, it only contains 1-3 nonzero
samples, corresponding to 0.2s - 0.6s of data, which suggests that the
mask-on slice was really that long rather than precisely 0. As a result,
it appears that the timestamps of the mask-on/mask-off slices are just the
current value of the machine's internal clock, which only has 1-second
resolution.
But rather than embark on herculean efforts to derive a sub-second slice
duration from (only occasionally present) event or waveform data, we just
treat the session as having no detailed data.
Because summaries used to be parsed incorrectly, there was a bunch of ugly
logic that was designed to infer the session start & end times from other data.
Now that the summary parsers work, that can all go away. The only change to
imported data is that sessions ending with the mask off are now longer, to
reflect that extra time before the machine was turned off.
Also clean up unused PRS1 channels and fix a regression from
9a25647c that broke unintentional leak calculation for CPAP/APAP.
Also add PRS1PressureAverageEvent to F0V4 list of supported events.
Right now this results in slightly confusing graphs, since sometimes
the IPAP/EPAP data for a machine is primarily reported by its settings
events, and for other machines by its statistics events. Also, the
"average" pressure on F0 looks like it might be effectivley EPAP in
single-pressure mode rather than the true average in bi-level mode.
Once we decide on the best presentation, we can either update the importer
or the display to show the most helpful channels for a given session.
Also warn when waveform files are being skipped on import due to this
kind of splitting.
The chunks YAML now emits all unique chunks found in files with the
same session ID.
Note that a single file can contain multiple chunks covering multiple
sessions. These will all be saved in the YAML file corresponding to the
original file's name, rather than the session ID encoded in any chunk.
This slight discrepancy is intentional, since the chunk YAML is meant
to test the parsers, to verify that they correctly decode a specific
input file. When importing data into a session, we use the actual
session ID specified by each chunk. Thus the session YAML files will
be derived from the proper chunks, regardless of their original
containing file. (Well, except for waveforms, but they don't appear
to have more than one session ID per file.)
F3V3 is unusual. Its events are recorded at fixed intervals like a waveform.
Its summary is recorded with absolute timestamps. Slices are each given their
own chunks in the event file.
This last oddity isn't yet handled.
While examining this, a few other importing issues have been cleaned up:
PRS1DataChunk::ParseEvents no longer needs the mode passed in as an argument,
F5V012 importers should quietly eat the newly parsed pressure
adjustment events until we can import both those and average pressure
statistics, and F5V012 importers should handle real VS events and treat
VS statistics like the other importers do.
