Re: [HC Evolution] Calendar to-do list

[Dan Winship <danw helixcode com>]

> I also don't think its that difficult to code actually. As long as the user
> can sync the Gregorian/time_t with the Real World Islamic date - then
> everything should be fine? Actually - all other software that does Islamic
> calendar doesn't even provide this feature - so its not really essential
> (i.e. it can be hardcoded in and changed each year or something)

Hard-coded? Ick. Here's how I imagine it could work:

The special Islamic->Gregorian mapping info would be stored in a
config file. You suggested earlier that someone could run a server
that tells what moon phase pronouncements have been made. Someone (you
maybe? :) writes a program (probably a perl or python script) that
connects to that server, and checks if the real calendar has slipped
relative to the predicted calendar. If it has, the script edits the
mapping file (not sure if it does this by itself or via a CORBA call
into the calendar) and then connects to the PCS, queries for any
events scheduled on Islamic dates, and reschedules them for the
correct new Gregorian dates. If this causes scheduling conflicts, it
warns you about them.

This way, the calendar itself is simpler; it never needs to deal with
changes in the Islamic->Gregorian mapping, because the changes always
occur behind its back.

Evolution is supposed to be heavily scriptable, so it should
(theoretically) be easy to set it up to run this calendar checking
script whenever necessary. (You just schedule it to be run on any date
when a calendar shift could be announced.)

Extremely anal people could do the same thing to query the
International Earth Rotation Service every six months to find out if
there's going to be a leap second, and insert it into their calendar
if so. :-)


On a side note: In Miguel's developerWORKS talk, he mentioned that
since GNOME is free-like-free-beer, it has the potential to beat out
MS in third-world countries where companies (and people) can't as
easily afford to buy expensive software. These are also some of the
markets that would be using non-Gregorian calendars, so having solid
support for "weird" calendars may turn out to be a really good thing.

-- Dan