The directory to store the session key, scrobble cache and log in.

The number of songs needed in the queue before an attempt to scrobble is
made.

This is a lambda or named function intended to take no arguments and return
a list where the first element is the track name, the second is the artist and
the third is the track length in seconds.

This is a lambda or named function intended to take no arguments and return
the current position in the track in seconds.

Get a copy of the contents of the *SCROBBLE-CACHE*.

When valid (as determined by VALID-SCROBBLE-P), add a song to the queue to be
scrobbled. If there is a network failure, the track will be stored for later
scrobbling when a connection is reestablished.

Ensure needed variables are set, restore the cache and settings if present
and, if scrobbling is enabled, restore or acquire a session key.

Loop indefinitely. If there are at least *SCROBBLE-COUNT* songs queued,
scrobble until the queue is empty or errors occur. Sleep 2 minutes and repeat.

Update the now playing status when *NOW-PLAYING-P* is non-NIL.

Toggle whether or not the Now Playing status is updated with each song.

Toggle whether or not new songs are added to the queue.

Set *LAST-SEEK* to the current track position via *SONG-TIME-FN*.

Set *SKIPPED* to the current track position via *SONG-TIME-FN*.

Set *SONG-INFO* to a list of (track artist duration timestamp) via
*SONG-INFO-FN* and UNIX-TIMESTAMP.