-- Extension description

-- Quellen:
-- http://scientificswede.blogspot.com/2012/05/extending-vlc-with-lua.html
-- http://macokratie.blogspot.de/2013/07/vlc-wiedergabe-fortsetzen-per-extension.html

-- Diesen Text in eine Textdatei speichern. Die Datei muss als "mempos.lua" benannt werden.

-- Installationspfad unter ubuntu:
-- Install by copy/pasting the below code to the file ~/.local/share/vlc/extensions/mempos.lua
-- Restart VLC and check the menu item View->Remember position

-- Installationspfad unter OS X:
-- Install the mempos.lua script in your home folder ~/Library/Application Support/org.videolan.vlc/lua/extensions/

-- Installationspfad unter Windows 7:
-- Unter dem VLC-Installationsordner, bei 64er-Version "C:\Program Files\VideoLAN\VLC" für den Unterordner "\lua" einen Unterordner "\extensions" anlegen und "mempos.lua" in diesen Ordner kopieren.


function descriptor()
 return { title = "Fortsetzungsposition" ;
	version = "1.1" ;
	author = "August (and Kantorde)" ;
	--url = 'http://www.opensubtitles.org/';
	shortdesc = "Remember file pos";
	description = "Remember file position.\n"
	.. "Maintains a database of current play position for all files played." ;
	capabilities = { "input-listener" }
 }
end

function serialize (o)
	if type(o) == "number" then
		io.write(string.gsub(o,",","."))
	elseif type(o) == "string" then
		io.write(string.format("%q", o))
	elseif type(o) == "table" then
		io.write("{\n")
		for k,v in pairs(o) do
			io.write("  [\"", k, "\"] = ")
			serialize(v)
			io.write(",\n")
		end
		io.write("}\n")
	else
		error("cannot serialize a " .. type(o))
	end
end
 
lastsavepos=0

function activate()
   vlc.msg.dbg("[remember pos] Welcome")

   local input = vlc.object.input()
   if input then
      vlc.var.add_callback(input, "intf-event", input_event_handler, "Hello world!")
   end
   datafile=vlc.misc.userdatadir().."/pos.txt"
   pcall(dofile,datafile)
   if input then input_changed() end 
end

function meta_changed()
end

function deactivate()
	vlc.msg.dbg("[remember pos] deact")
	local input = vlc.object.input()
	if input then
		vlc.var.del_callback(input, "intf-event", input_event_handler, "Hello world!")
	end
end

input=0
filelist={}
currentitem=""

function savedb()
-- save position database
	io.output(datafile)
	io.write("filelist=")
	serialize(filelist)
	io.close()
end

function input_changed()
	if not input== 0 then
-- Delete old callback
		vlc.var.del_callback(input, "intf-event", input_event_handler, "Hello world!")
	end
	savedb()
	vlc.msg.dbg("[remember pos] input changed..!")
	item=vlc.item or vlc.input.item()
	currentitem=item:name()
	input = vlc.object.input()
	vlc.var.add_callback(input, "intf-event", input_event_handler, "Hello world!")
	local elapsed_time=filelist[currentitem]
	if (elapsed_time) then 
		vlc.var.set(input, "time",elapsed_time)
		vlc.msg.dbg("[remember pos] Found item in db")
	end
		lastsavepos=elapsed_time
	return false
end

function input_event_handler(var, old, new, data)
	local elapsed_time = vlc.var.get(input, "time")
-- print(input)
	filelist[currentitem]=elapsed_time
-- catch if lastsavepos is nil
	if not tonumber(lastsavepos) then
		lastsavepos = 0
	end
--save file every 10 seconds
	if elapsed_time>lastsavepos+10 or elapsed_time<lastsavepos then
		savedb();
		lastsavepos=elapsed_time;
	end
end