playlist: Create a function for changing the current tag

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

playlist/model.py

@@ -4,24 +4,43 @@ from gi.repository import GObject, Gio
 class TagModel(GObject.GObject, Gio.ListModel):
     def __init__(self, tag=None):
         GObject.GObject.__init__(self)
+        self.items = [ ]
+        self.__set_tag__(tag)
+
+    def __set_tag__(self, tag):
         self.tag = tag
+        if self.tag != None:
+            self.items = self.tag.tracks.copy()
+            self.tag.TrackAdded.register(self.track_added)
+            self.tag.TrackRemoved.register(self.track_removed)
+        return len(self.items)
+
+    def __unset_tag__(self):
+        n = len(self.items)
+        if self.tag:
+            self.tag.TrackAdded.unregister(self.track_added)
+            self.tag.TrackRemoved.unregister(self.track_removed)
+            self.items.clear()
+        return n
 
     def do_get_item_type(self):
         return GObject.TYPE_PYOBJECT
 
     def do_get_n_items(self):
-        if self.tag:
-            return len(self.tag)
-        return 0
+        return len(self.items)
 
     def do_get_item(self, n):
-        if self.tag:
-            return self.tag[n]
-
-    def do_get_object(self, n):
-        return self.tag[n]
+        if n < len(self.items):
+            return self.items[n]
 
     def switch_tag(self, tag):
-        prev = len(self.tag) if self.tag else 0
-        self.tag = tag
-        self.items_changed(0, prev, len(self.tag))
+        self.items_changed(0, self.__unset_tag__(),
+                              self.__set_tag__(tag))
+
+    def track_added(self, tag, track, pos):
+        self.items.insert(pos, track)
+        self.items_changed(pos, 0, 1)
+
+    def track_removed(self, tag, track, pos):
+        self.items.remove(track)
+        return self.items_changed(pos, 1, 0)

playlist/test_model.py

@@ -20,17 +20,32 @@ class TestTagModel(unittest.TestCase):
         self.assertIsInstance(m, GObject.Object)
         self.assertIsInstance(m, Gio.ListModel)
 
+        self.assertEqual(m.tag, t)
+        self.assertEqual(m.items, [ ])
+
         self.assertEqual(m.get_item_type(), GObject.TYPE_PYOBJECT)
         self.assertEqual(m.get_n_items(), 0)
         self.assertIsNone(m.get_item(0))
 
-        t.add_track(fake.Track(1))
+    def test_tag_model_add_remove(self):
+        t = tag.Tag("Test")
+        m = model.TagModel(t)
+        track = fake.Track(1)
+
+        t.add_track(track)
+        self.assertEqual(m.items, [ track ])
         self.assertEqual(m.get_n_items(), 1)
         self.assertEqual(m.get_item(0), fake.Track(1))
 
+        t.remove_track(track)
+        self.assertEqual(m.items, [ ])
+        self.assertEqual(m.get_n_items(), 0)
+        self.assertIsNone(m.get_item(0))
+
     def test_tag_model_init_none(self):
         m = model.TagModel()
 
+        self.assertEqual(m.items, [ ])
         self.assertEqual(m.get_n_items(), 0)
         self.assertIsNone(m.get_item(0))
 
@@ -47,6 +62,9 @@ class TestTagModel(unittest.TestCase):
 
         m.switch_tag(t)
         self.assertEqual(self.changed, (0, 0, 2))
+        self.assertIn(m.track_added, t.TrackAdded.subscribers)
 
         m.switch_tag(u)
         self.assertEqual(self.changed, (0, 2, 1))
+        self.assertIn(m.track_added, u.TrackAdded.subscribers)
+        self.assertNotIn(m.track_added, t.TrackAdded.subscribers)

sidebar/tagbox.py

@@ -2,6 +2,7 @@
 from . import tagrow
 from gi.repository import Gtk
 import lib
+import playlist
 import trackdb
 
 class TagBox(Gtk.ScrolledWindow):
@@ -23,6 +24,7 @@ class TagBox(Gtk.ScrolledWindow):
         if header == True:
             self.listbox.set_header_func(self.header_func)
         self.listbox.connect("row-activated", self.row_activated)
+        self.listbox.connect("row-selected", self.row_selected)
 
         tagstore.Added.register(self.tag_added)
         tagstore.Removed.register(self.tag_removed)
@@ -48,6 +50,9 @@ class TagBox(Gtk.ScrolledWindow):
     def row_activated(self, listbox, row):
         trackdb.Stack.push(row.tag)
 
+    def row_selected(self, listbox, row):
+        playlist.Model.switch_tag(row.tag)
+
     def sort_func(self, lhs, rhs):
         if lhs.tag < rhs.tag:
             return -1

test_playlist.py

@@ -1,5 +1,6 @@
 # Copyright 2021 (c) Anna Schumaker.
 from gi.repository import Gtk
+import lib
 import playlist
 import unittest