#
#   Information fetching interfaces
#

lyric_fetching(artist, title) -> Lyrics

cover_fetching(artist, album) -> ??


#
#   Ui interfaces
#

button_construst() -> Gtk.Button

tab_construct() -> (tab content, icon name, tab name, the widget to focus on tab switch)

#
#   Other
#

# Called when one of the following items are changed:
#  1. Current playlist (song added, removed, etc)
#  2. Repeat/random/xfade/volume
#  3. Currently selected song in playlist
#  4. Status (playing/paused/stopped)

handle_change_status(state, prevstate, prevsonginfo, songinfo, mpd_time_now)

# Called when song changes:

playing_song_observers(songinfo)

# This gets called when the plugin is loaded, enabled, or disabled:

on_enable(state):
