lib: Create a TagStore with add and remove functions

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

lib/tagstore.py

@@ -0,0 +1,19 @@
+# Copyright 2021 (c) Anna Schumaker.
+from . import tag
+
+class TagStore:
+    def __init__(self):
+        self.store = dict()
+
+    def add(self, name, track):
+        name = name.strip()
+        if (t := self.store.get(name)) == None:
+            t = tag.Tag(name)
+            self.store[name] = t
+        t.add_track(track)
+        return t
+
+    def remove(self, t, track):
+        t.remove_track(track)
+        if len(t) == 0 and t in self.store.values():
+            self.store.pop(t.name)

lib/test_tagstore.py

@@ -0,0 +1,24 @@
+# Copyright 2021 (c) Anna Schumaker.
+from . import tagstore
+import unittest
+
+class TestTagStore(unittest.TestCase):
+    def test_tag_store(self):
+        store = tagstore.TagStore()
+        self.assertEqual(store.store, { })
+
+    def test_tag_store_add_remove(self):
+        store = tagstore.TagStore()
+        tag = store.add("test", 1)
+        self.assertEqual(tag.tracks, [ 1 ])
+
+        self.assertEqual(store.add("test  ", 2), tag)
+        self.assertEqual(tag.tracks, [ 1, 2 ])
+
+        store.remove(tag, 1)
+        self.assertEqual(tag.tracks, [ 2 ])
+        self.assertIn("test", store.store.keys())
+
+        store.remove(tag, 2)
+        self.assertEqual(tag.tracks, [ ])
+        self.assertNotIn("test", store.store.keys())