libsaria: New sequential next function for playlist

The new function exists in its own file to keep things simpler.  Based
on the current song id, it finds the index in the playlist and returns
the next visible song.

libsaria/sources/__init__.py

@@ -63,9 +63,10 @@ def play_id(id):
 
 def next():
 	global cur_id
-	cur_id = queue.next()
-	if cur_id == None:
-		cur_id = playlist.get_next(cur_id)
+	id = queue.next()
+	if id == None:
+		id = playlist.get_next(cur_id)
+	cur_id = id
 	return library.get_attrs(cur_id, "filepath")
 
 def list_source(source, *attrs):

libsaria/sources/playlist/__init__.py

@@ -3,6 +3,7 @@
 import libsaria
 from libsaria.sources import library
 import playlist
+import next
 import random
 
 filtered   = False
@@ -49,18 +50,6 @@ def num_visible():
 def get_cur_id():
 	return playlist.song_list[cur_index]
 
-def seq_next():
-	global cur_index
-	cur_index += 1
-	max_index  = len(playlist.song_list)
-	if cur_index == max_index:
-		cur_index = 0
-	while is_visible(playlist.song_list[cur_index]) == False:
-		cur_index += 1
-		if cur_index == max_index:
-			cur_index = 0
-	return playlist.song_list[cur_index]
-
 def rand_candidate(list, max):
 	index = random.randint(0, max-1)
 	return list[index]
@@ -113,7 +102,8 @@ def get_next(cur_id):
 	if libsaria.prefs.get("libsaria.random") == True:
 		id = rand_next()
 	else:
-		id = seq_next()
+		index = next.seq_next(cur_id)
+		id = playlist.get(index)
 	if id != None:
 		artist, title, file = library.get_attrs(id, "artist", "title", "filepath")
 		recent.append((artist, title))

libsaria/sources/playlist/next.py

@@ -0,0 +1,20 @@
+# Bryan Schumaker (5 / 14 / 2011)
+
+import playlist
+
+def incr_index(cur_index, max_index):
+	cur_index += 1
+	if cur_index == max_index:
+		cur_index = 0
+	return cur_index
+
+def seq_next(cur_id):
+	from libsaria import sources
+	is_visible = sources.playlist.is_visible
+
+	index = playlist.index(cur_id)
+	max   = playlist.size()
+	index = incr_index(index, max)
+	while not is_visible(playlist.get(index)):
+		index = incr_index(index, max)
+	return index

libsaria/sources/playlist/playlist.py

@@ -49,3 +49,27 @@ def as_set():
 	song_set = set(song_list)
 	unlock_plist()
 	return song_set
+
+def size():
+	lock_plist()
+	sz = len(song_list)
+	unlock_plist()
+	return sz
+
+def index(item):
+	lock_plist()
+	try:
+		idx = song_list.index(item)
+	except:
+		idx = -1
+	unlock_plist()
+	return idx
+
+def get(index):
+	lock_plist()
+	try:
+		item = song_list[index]
+	except:
+		item = None
+	unlock_plist()
+	return item