IdConv.lua

ItemData = {}
ItemData.mt = {}
ItemData.mt.__tostring = function(data)
	return data.id .. ":" .. data.meta .. "  =>  " .. data.name
end

ItemData.create = function (arg)
	local itemdata = {	name = arg.name,
					    tooltip = arg.tooltip,
					    id = arg.id,
						meta = arg.meta}
	setmetatable(itemdata,ItemData.mt)
	return itemdata
end

ItemData.ErrorItemNotFound = function (id,meta)
	local err = "!!Data Not Found for " .. id .. ":" .. meta .. "!!"
	local itemdata = {	name = err,
					    tooltip = err,
						id = id,
						meta = meta}
	setmetatable(itemdata,ItemData.mt)
	return itemdata
end




IdConv = {}
IdConv.__index = IdConv

function IdConv.create(filename)
	local conv = {}             -- our new object
	setmetatable(conv,IdConv)
	conv.filename=filename

	local loaddata = function (filename)
		 -- Load the File
		local fh = fs.open(filename,"r")
		local datafor = {}
		for line in fh.readLine do
			for idstr, metastr, name, tooltip in string.gmatch(string.lower(line), "(%d-):(%d-) = (.+) = (.+)" ) do
				local id = tonumber(idstr)
				local meta = tonumber(metastr)

				datafor[id] = datafor[id] or {} -- initalise it if it hasn't already been initalised
				datafor[id][meta] = ItemData.create{ id=id,
													meta = meta,
													name = name,
													tooltip = tooltip,
													}
			end
		end
		fh.close()
		return datafor
	end

	conv.datafor = loaddata(filename)

	return conv
end


function IdConv:getDataFor(id, meta)
	local idData = self.datafor[id]
	if (idData) then

		--Got info about this item,
		local exactItemData = idData[meta]
		if exactItemData then
			return exactItemData
		else
			-- Exact meta not matched, pick first on record that has am id
			-- This is the case for a damaged sword etc
			local _, firstValue = next(idData)
			return firstValue
		end
	else
		return ItemData.ErrorItemNotFound(id,meta)
	end
end

 ------------- UUID related -----------------

function IdConv:getUuid(id,meta)
	return id + meta * 32768
end

function IdConv:getFullID(uuid)
	local ret = {}
	if uuid > 32768 then
		ret.id = uuid%32768
		ret.meta = (uuid - ret.id)/32768
	else
		ret.id = uuid
		ret.meta = 0
	end
	return ret
end