libsaria: Add dynamic attributes

Dynamic attributes are attributes of a track that can change during run
time (like status, playcount, etc).  I only initialize these when they
are first set, and I save after each change.

This patch adds in the dattr framework and the "like" dattr.

libsaria/sources/__init__.py

@@ -8,7 +8,9 @@ expand  = libsaria.path.expand
 import library
 import playlist
 import queue
+import attrs
 
+attrs.load_dattrs()
 cur_id = None
 
 def inc_count():
@@ -21,11 +23,14 @@ def find_attrs(file, *attrs):
 	track = library.track.Track(file)
 	if track == None:
 		return
+	id    = library.update.song_id(file)
 	get   = track.__dict__.get
 	res   = []
 	for attr in attrs:
 		if attr == "id":
-			res.append(library.update.song_id(file))
+			res.append(id)
+		elif attr == "like":
+			res.append(attrs.get_dattr(id, "like"))
 		else:
 			res.append(get(attr))
 	return res
@@ -55,9 +60,9 @@ def is_visible(id):
 	return library.is_visible(id)
 
 def set_attr(attr, value):
-	if cur_source:
-		cur_source.set_attr(cur_id, attr, value)
-		cur_source.save()
+	id = get_attrs("id")[0]
+	if id:
+		attrs.set_dattr(id, attr, value)
 
 def make_library(path):
 	path = expand(path)

libsaria/sources/library/library.py

@@ -2,10 +2,12 @@
 
 import threading
 from libsaria import storage
+from libsaria.sources import attrs
 
 library_lock   = threading.Lock()
 lock_library   = library_lock.acquire
 unlock_library = library_lock.release
+get_dattr      = attrs.get_dattr
 
 # Map directory -> dict()
 lib_dict = None
@@ -62,6 +64,8 @@ def get_attrs(id, *attrs):
 	for attr in attrs:
 		if attr == "id":
 			res.append(id)
+		elif attr == "like":
+			res.append(get_dattr(id, attr))
 		else:
 			res.append(get(attr))
 	unlock_library()