rule-based tagging in lieu of protocol icons

[Aleks Bromfield]

One of the argument that people have raised in favor of
protocol icons is that sometimes you care about the
properties of the network you're using. For example, you'd
prefer to talk to someone over a secure or internal
connection, and if that's not possible, then you'd like to
know so that you can avoid sharing any private information.

I think that this, and all other objections, can be solved
by adding tag support and a rule-based tagging scheme.
Basically, the user could define rules, like email filtering
rules, which attached tags to certain buddies based on any
category they want, and they could apply those rules at any
time. This system could replace traditional buddy groups, as
well; a contact now just has a set of tags.

Think of this as the difference between Gmail-style labels
and traditional mail folders. With the old protocol-based
system, we assumed that protocol was the only category that
people want to sort on. With this system, we recognize that
people want to put their buddies into multiple categories,
or sort them according to arbitrary rules.

To actually make this meaningful, you'd probably also want
to set a list of "important" tags, which get displayed
alongside the name of any contact with that tag (or,
optionally, a picture could be used), as well as a list of
"buddy list" tags, which would look like groups in the
current system.

I'll be glad to look into writing this code; I think it
would mostly be a matter of refactoring how groups are
implemented, and adding a dialog for the rule creator. That
said, I'd have to learn how pidgin's codebase works first...
so if someone else agrees this is a good idea and wants to
help me out, that would be awesome.

Thoughts?

~ Aleks