We want to store the calculated dtstart and dtend in the database so we can
use SQL to fetch records. However, we also need what the user sent us so we
can allow prop-filters to be used as well.
So we store what the user sends us in dtstart_orig and dtend_orig and only
use for relevant prop-filter reports.
If we force setting DTSTART, then you can't use prop-filter to find VTODOs
with a DUE set and DTSTART unset. And, well, why should DTSTART be set to DUE?
This was introduced in 18150d702d91fa1a687801baa582d967e79fff8d .
As specified in RFC5545 the CLASS field is optional, and if it isn't present
is treated as PUBLIC. To allow a is-not-defined prop-filter to find
resources without CLASS set, we need to not store in the database. This
turns out to be okay, because to enforce privacy we always check to see if
it is PRIVATE or CONFIDENTIAL. We never check to see if it is PUBLIC.
Closes#284.
Gosh, this was completely broken previously. A number of different scenarios now work.
I have used some of the state I've seen in a largish production database with the
presence of NULL and empty strings. I've assumed that empty string should be treated
as is-not-defined. Happy to be talked out of that.
Closes#281.
