curds: Begin implementing a playlist manager

This will give us a single place for the UI to look up and control
playlists.

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

curds/playlist/__init__.py

@@ -1 +1,12 @@
 # Copyright 2019 (c) Anna Schumaker.
+from . import library
+import os
+
+plist_map = {"Library" : dict()}
+
+def lookup_library(path):
+    path  = os.path.abspath(path)
+    plist = plist_map["Library"].get(path, None)
+    if plist != None:
+        return plist
+    return plist_map["Library"].setdefault(path, library.LibraryPlaylist(path))

curds/test_playlist.py

@@ -0,0 +1,34 @@
+# Copyright 2019 (c) Anna Schumaker.
+from . import playlist
+from . import threadqueue
+import os
+import unittest
+
+test_album   = os.path.abspath("./trier/Test Album")
+test_library = os.path.abspath("./trier/Test Library")
+
+class TestPlaylistManager(unittest.TestCase):
+    def setUpClass():
+        if not playlist.library.library_thread.is_alive():
+            playlist.library.library_thread = threadqueue.ThreadQueue()
+
+    def tearDownClass():
+        playlist.library.library_thread.stop()
+
+    def test_playman_init(self):
+        self.assertIsInstance(playlist.plist_map, dict)
+        self.assertEqual(playlist.plist_map["Library"], {})
+        self.assertTrue(playlist.library.library_thread.is_alive())
+
+    def test_playman_lookup_library(self):
+        plist = playlist.lookup_library(test_library + "/")
+        self.assertIsInstance(plist, playlist.library.LibraryPlaylist)
+        self.assertEqual(plist.name, test_library)
+        self.assertEqual(plist, playlist.plist_map["Library"][test_library])
+        self.assertEqual(playlist.lookup_library(test_library), plist)
+        self.assertEqual(len(playlist.plist_map["Library"].values()), 1)
+
+        alist = playlist.lookup_library(test_album)
+        self.assertIsInstance(alist, playlist.library.LibraryPlaylist)
+        self.assertIn(alist, playlist.plist_map["Library"].values())
+        self.assertIn(plist, playlist.plist_map["Library"].values())