Fixes#321. Due to the extremely large quantity of comments on a
typical Motte post, 'hot' sorting logic underflowed an intermediate
value. Roughly:
|(-1 000 000) * (103 [votes] + 1 + 2723 [comments] / 1)| > 2^31
We resolve this by reducing the coefficient from 1e6 to 1e5, which
reduces precision of intermediate calculations somewhat, and by
dividing #comments by 10 rather than 1, which better matches Motte
user behavior regardless: Users comment much more often than vote.
This buys us two orders of magnitude more headroom before out-of-
bounds. Shouldn't be an issue until the CW thread reaches ~200k
comments.
Moves behavior in api_comment that updates stateful counters and
generates notifications into a function which can also be called
if a filtered comment is approved. Fixes#272.
Incidentally, also fixes#278 by adding another filter to the post
subscribers query during general clean-up/refactoring.
Originally was going to move this function into the Comments model,
since assurances about state (even with side effects) should probably
be made there, but I couldn't find a sane way to untangle the imports.
Resolves root problem of non-admin users seeing comments they shouldn't
by JOINing on the appropriate fields and including them in the WHERE
clause of the query.
In the process, was also able to remove some unperformant queries
that used (potentially extremely long) lists passed to WHERE clauses in
lieu of proper JOINs.
