on-demand calculation and update of option info

Using metatables to calculate info strings on render, we can avoid
precomputing it for all options when generating the menu, making certain
menus open much faster. This also allows us to update dynamic info, e.g.
the currently programme, while the menu is open.

1 files changed, 6 insertions, 8 deletions

diff --git a/osd.lua b/osd.lua
index 58c6903..7075a73 100644
--- a/osd.lua
+++ b/osd.lua
@@ -235,8 +235,9 @@ function mt:option_text(opt, info)
 		str = col .. '[' .. str .. ']'
 	end
 
-	if opt.info and #opt.info > 0 then
-		str = str .. colour.info .. ' (' .. asscape(opt.info) .. ')'
+	local opt_info = opt.info
+	if opt_info and #opt_info > 0 then
+		str = str .. colour.info .. ' (' .. asscape(opt_info) .. ')'
 	end
 
 	return str
@@ -542,6 +543,8 @@ function mt:render()
 end
 
 function mt:redraw(state)
+	self.redraw_time = os.time()
+
 	local out_titles = {}
 	local out_options = {}
 
@@ -574,15 +577,10 @@ function mt:redraw(state)
 			#menu.options) do
 		local opt = menu.options[i]
 
-		-- use real-time count for favourites
-		if opt.id == 'favourites' then
-			opt.info = tostring(#state.favourites)
-		end
-
 		local selected = i == menu.cursor and not menu.search_active
 		local info = {
 			selected = selected,
-			empty = (opt.type == 'group' and not opt.lazy and
+			empty = (opt.type == 'group' and opt.children and
 				#opt.children == 0),
 			playing = not not (
 				opt.id and opt.id == state.playing_id),