list

dir = "+Y"
n = 0

local directions = { [0]=0,[1]=1,[2]=2,[3]=3,[4]=4,[5]=5,["down"] = 0, ["up"] = 1, ["-Z"] = 2, ["+Z"] = 3, ["-X"] = 4, ["+X"] = 5, ["+Y"] = 1, ["-Y"] = 0}
sorter = peripheral.wrap("back")

function getitem(dir,invdir)
	itemcount = 0
	for id,count in pairs(sorter.list(directions[invdir])) do
		itemid = id
		itemcount = itemcount + count
	end
end

function update()
	getitem("back",dir)
	n = n + 1
	print("Sent update #"..n)
	if itemcount > 0 then
		item = { [1]="item", [2]=itemname, [3]=itemcount }
		text = textutils.serialize(item)
		rednet.broadcast(text)
	else
		item = { [1]="item", [2]=itemname, [3]=0 }
		text = textutils.serialize(item)
		rednet.broadcast(text)
	end
end

if fs.exists("i") then
	local file = io.open("i","r")
	itemname = file.read()
	print("Item name: "..itemname)
	rednet.open("bottom")
	update()
	active = true
else
	print("No itemname!")
	active = false
end

while active do
	event,id,message = os.pullEvent()
	if event == "rednet_message" then
		order = textutils.unserialize(message)
		if message == "updatestock" then
			update()
		end
		if string.sub(message,1,1) == "{" then
			if order[1] == "order"..itemname then
				extracted = order[2]
				while extracted > 0 do
					if extracted >= 64 then
						sorter.extract(directions[dir],itemid,directions["-Y"],64)
						extracted = extracted - 64
					else
						sorter.extract(directions[dir],itemid,directions["-Y"],extracted)
						extracted = 0
					end
					os.sleep(0.2)
				end
				update()
			end
		end
	end
end