local class   = require('class')
local itemDB  = require('core.itemDB')
local Util    = require('util')

local device = _G.device

local Adapter = class()

function Adapter:init(args)
	if args.side then
		local inventory = device[args.side]
		if inventory then
			Util.merge(self, inventory)
		end
	end
end

function Adapter:listItems(throttle)
	local cache = { }
	throttle = throttle or Util.throttle()

	for k,v in pairs(self.list()) do
		if v.count > 0 then
			local key = table.concat({ v.name, v.damage, v.nbtHash }, ':')

			local entry = cache[key]
			if entry then
				entry.count = entry.count + v.count
			else
				cache[key] = itemDB:get(v, function() return self.getItemMeta(k) end)
			end
			throttle()
		end
	end

	-- TODO: cache number of slots, free slots, used slots
	-- useful for when inserting into chests
	-- ie. insert only if chest does not have item and has free slots

	self.cache = cache
end

return Adapter