The previous approach worked when the user pushes their due date back,
or moves it forward a little bit, but breaks down if they reschedule
shortly after the previous answer - a card that was only just answered
will have had an effective delay of 0, causing the interval to be
reset, which is not great.
I thought about limiting interval reductions, but that means the
behaviour is inconsistent when sending a card forward and moving it
back again.
We could apply a cap to the amount of interval we'll reduce, but that
will either doing something like dividing by 2 (which breaks down when
the action is performed repeatedly), or or looking up the review log
to try and determine the previous interval we should not go below.
One other option we might want to consider in the future is using
the revlog to calculate the actual elapsed time at answer time instead
of reschedule time, falling back to existing behaviour when the revlog
doesn't match or is missing.
The old rescheduling dialog's two options have been split into two
separate menu items, "Forget", and "Set Due Date"
For cards that are not review cards, "Set Due Date" behaves like the
old reschedule option, changing the cards into a review card, and
and setting both the interval and due date to the provided number of
days.
When "Set Due Date" is applied to a review card, it no longer resets
the card's interval. Instead, it looks at how much the provided number
of days will change the original interval, and adjusts the interval by
that amount, so that cards that are answered earlier receive a smaller
next interval, and cards that are answered after a longer delay receive
a bonus.
For example, imagine a card was answered on day 5, and given an interval
of 10 days, so it has a due date of day 15.
- if on day 10 the due date is changed to day 12 (today+2), the card
is being scheduled 3 days earlier than it was supposed to be, so the
interval will be adjusted to 7 days.
- and if on day 10 the due date is changed to day 20, the interval will
be changed from 10 days to 15 days.
There is no separate option to reset the interval of a review card, but
it can be accomplished by forgetting the card(s), and then setting the
desired due date.
Other notes:
- Added the action to the review screen as well.
- Set the shortcut to Ctrl+Shift+D, and changed the existing Delete
Tags shortcut to Ctrl+Alt+Shift+A.
Closes#766
- changes the on-disk representation from % to a multiplier,
eg 250 -> 2.5, as this is consistent with the other options
- resets deck configs at or below 1.3 to 2.5
- for any cards that were using a reset deck config, reset their
current factor if it's at or below 2.0x. The cutoff is arbitrary,
and just intended to make sure we catch cards the user has rated
Easy on multiple times. The existing due dates are left alone.
