audio: Give the Player a set_playlist() function

With a callback to notify when the current playlist changes.
Additionally, I make sure to reset playlist.current if the playlist has
previously finished playing.

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

audio/player.py

@@ -1,4 +1,5 @@
 # Copyright 2021 (c) Anna Schumaker.
+import db
 import lib
 import tagdb
 from gi.repository import GObject
@@ -12,8 +13,10 @@ class Player(bass.BassPlayer):
         bass.BassPlayer.__init__(self)
         self.Autopause = scale.AutoPauseScale()
         self.Selector = selector.TagdbSelector()
+        self.playlist = None
         self.track = None
 
+        self.set_playlist(db.find_playlist(lib.settings.get_int("audio.plstateid")))
         self.change_track(tagdb.Tracks[lib.settings.get_int("audio.trackid")])
         if self.track:
             self.track.add_to_playlist("Previous")
@@ -46,9 +49,23 @@ class Player(bass.BassPlayer):
     def next(self): self.play_track(self.Selector.next())
     def previous(self): self.play_track(self.Selector.previous())
 
+    def set_playlist(self, plist):
+        if plist is None:
+            plist = db.user.Table.find("Collection")
+        if plist != self.playlist:
+            self.emit("playlist-changed", self.playlist, plist)
+
     @GObject.Signal(arg_types=(tagdb.track.Track, tagdb.track.Track))
     def track_changed(self, prev, new):
         self.track = new
         if self.track:
             lib.settings.set("audio.trackid", new.trackid)
             self.uri = new.filepath().absolute().as_uri()
+
+    @GObject.Signal(arg_types=(db.playlist.Playlist, db.playlist.Playlist))
+    def playlist_changed(self, prev, new):
+        self.playlist = new
+        if self.playlist:
+            if new.current >= new.get_n_tracks() - 1:
+                new.current = -1
+            lib.settings.set("audio.plstateid", new.plstateid)

audio/test_player.py

@@ -1,4 +1,5 @@
 # Copyright 2021 (c) Anna Schumaker.
+import db
 import lib
 import pathlib
 import tagdb
@@ -52,6 +53,9 @@ class TestPlayer(unittest.TestCase):
     def on_track_changed(self, player, prev, new):
         self.changed = (prev, new)
 
+    def on_playlist_changed(self, player, prev, new):
+        self.changed = (prev, new)
+
     def test_player_init(self):
         play = player.Player()
         self.assertIsInstance(play, bass.BassPlayer)
@@ -60,6 +64,40 @@ class TestPlayer(unittest.TestCase):
         self.assertIsInstance(play.Selector, selector.Selector)
         self.assertIsNone(play.track)
 
+        self.assertEqual(play.playlist, db.user.Table.find("Collection"))
+        self.assertEqual(lib.settings.get_int("audio.plstateid"),
+                         db.user.Table.find("Collection").plstateid)
+
+    def test_set_playlist(self):
+        collection = db.user.Table.find("Collection")
+        plist = db.user.Table.find("Test Playlist")
+        play = player.Player()
+        play.connect("playlist-changed", self.on_playlist_changed)
+
+        play.set_playlist(plist)
+        self.assertEqual(play.playlist, plist)
+        self.assertEqual(self.changed, (collection, plist))
+        self.assertEqual(lib.settings.get_int("audio.plstateid"), plist.plstateid)
+
+        self.changed = None
+        play.set_playlist(plist)
+        self.assertIsNone(self.changed)
+
+        play2 = player.Player()
+        self.assertEqual(play2.playlist, plist)
+
+        play2.set_playlist(None)
+        self.assertEqual(play2.playlist, collection)
+
+    def test_set_playlist_reset(self):
+        plist = db.user.Table.find("Test Playlist")
+        plist.add_track(db.make_fake_track(1, 1, "Test 1", "/a/b/c/1.ogg"))
+        plist.current = 0
+
+        play = player.Player()
+        play.set_playlist(plist)
+        self.assertEqual(plist.current, -1)
+
     def test_change_track(self):
         play = player.Player()
         play.connect("track-changed", self.on_track_changed)