local chest
for _,name in ipairs(peripheral.getNames()) do
	if name:match("chest") then chest = peripheral.wrap(name) break end
end
assert(chest,"couldn't find chest")
-- might not work if there are multiple modems but why would you do that
local localname = peripheral.find("modem").getNameLocal()

local function take_stock()
	-- if you do this in parallel, you avoid having to wait 1 tick for each
	-- slot of the chest. which is probably good.
	local out = {}
	local fns = {}
	for i=1,chest.size() do
		fns[i] = function() out[i] = chest.getItemDetail(i) end
	end
	parallel.waitForAll(unpack(fns))
	return out
end

local function item_desc_matches(idesc,itemdetail)
	-- idesc is an entry from ITEMS
	-- itemdetail is something returned from getItemDetail on the chest
	-- if you were wondering
	return idesc.itname == itemdetail.name
end

local function stock_amt(stockinfo,idesc)
	local total = 0
	for ix,itm in pairs(stockinfo) do
		if item_desc_matches(idesc,itm) then
			total = total + itm.count
		end
	end
	return total
end