libsaria: Move rand_next() to playlist's next.py

This keeps code for picking the next song in one place.  I also cleaned
up rand_next() while I was at it.

libsaria/sources/playlist/__init__.py

@@ -17,6 +17,7 @@ cur_index  = None
 add_ids = playlist.add_ids
 rm_ids  = playlist.rm_ids
 reset   = playlist.reset
+to_list = list
 
 playlist.load()
 
@@ -50,37 +51,6 @@ def num_visible():
 def get_cur_id():
 	return playlist.song_list[cur_index]
 
-def rand_candidate(list, max):
-	index = random.randint(0, max-1)
-	return list[index]
-
-def rand_next():
-	global cur_index
-	n = num_visible()
-	if n == 0:
-		return
-	get_attrs = library.get_attrs
-
-	if filtered == False:
-		selection = playlist.song_list
-	else:
-		selection = list(visible)
-
-	for i in xrange(15):
-		id = rand_candidate(selection, n)
-		(artist, title, like) = get_attrs(id, "artist", "title", "like")
-		if (artist, title) in recent:
-			print recent_msg % (artist, title)
-			continue
-		if like == False:
-			print skip_msg % (artist, title)
-			continue
-		if i > 0:
-			print "Picking a song took %s iterations" % i
-		cur_index = playlist.song_list.index(id)
-		return id
-	return id
-
 def load_id(id):
 	global cur_index
 	cur_index = playlist.song_list.index(id)
@@ -97,16 +67,18 @@ def play_id(id):
 
 def get_next(cur_id):
 	id = None
-	if len(playlist.song_list) == 0:
-		return
 	if libsaria.prefs.get("libsaria.random") == True:
-		id = rand_next()
+		if filtered == False:
+			index = next.rand_next(playlist.song_list)
+		else:
+			index = next.rand_next(to_list(visible))
 	else:
 		index = next.seq_next(cur_id)
+	if index != None:
 		id = playlist.get(index)
 	if id != None:
 		artist, title, file = library.get_attrs(id, "artist", "title", "filepath")
-		recent.append((artist, title))
+		next.recent.append((artist, title))
 		if len(recent) > 50:
 			recent.pop(0)
 		return id

libsaria/sources/playlist/next.py

@@ -1,6 +1,10 @@
 # Bryan Schumaker (5 / 14 / 2011)
 
+import random
 import playlist
+from libsaria.sources import library
+
+recent = []
 
 def incr_index(cur_index, max_index):
 	cur_index += 1
@@ -12,9 +16,31 @@ def seq_next(cur_id):
 	from libsaria import sources
 	is_visible = sources.playlist.is_visible
 
-	index = playlist.index(cur_id)
 	max   = playlist.size()
+	if max == 0: # List is empty
+		return
+
+	index = playlist.index(cur_id)
 	index = incr_index(index, max)
 	while not is_visible(playlist.get(index)):
 		index = incr_index(index, max)
 	return index
+
+def check_candidate(id):
+	(artist, title, like) = library.get_attrs(id, "artist", "title", "like")
+	if (artist, title) in recent:
+		return False
+	if like == False:
+		return False
+	return True
+
+def rand_next(list):
+	max = len(list) - 1
+	if max == -1: # List is empty
+		return
+	for i in xrange(15):
+		index = random.randint(0, max)
+		id    = list[index]
+		if check_candidate(id) == True:
+			break
+	return playlist.index(id)