I've essentially loaded up the string distance function with heuristics that
apply different weights to different kinds of string cruft that one encounters
in music tags. For example, tracks ending with "feat. Somebody" shouldn't be
penalized for all those extra characters. Now the weight of that part of the
string is significantly reduced.
That is, in addition to contributing to the distance function, the plugin can
also influence the initial search into MusicBrainz. This will allow albums to be
tagged even when they're missing metadata entirely. This change required a
significant bit of refactoring to the "mb" module -- it's much nicer now.
This involves yet another new plugin method: album_distance. This leaves as the
last major puzzle piece for lastid the ability to augment the initial search
into MB (i.e., can start a search using fingerprinted metadata).
This required the introduction of a track_distance method on plugins. We'll also
need to add an album_distance method as well as a mechanism for extending the
search routine (so we can search for albums in MusicBrainz even when they have
no tags). This commit also adds the '-v' flag for printing debug logs (something
we should do more of).
(I'm not sure why, but the weight for track index mismatches was set to 0.0.
This way, the tagger will be slightly more reluctant to frivolously reorder.)
When computing track destination paths, we now look for album-level values when
they're available. This has the effect of making albums go into a single
directory even when their tracks have heterogeneous metadata. We will need to
revisit this once we start explicitly supporting non-album tracks.
