MTA encodeString filesize fix

encodeString-filesize-fix.lua

local KEY = "sampletext"

addEventHandler("onResourceStart", resourceRoot, function()
	-- ENCODE
	local file = File.open("test.txt")
	local raw = file:read(file.size)
	file:close()

	local len = #raw
	local lent = {}

	-- file length to 256-digit notation
	local len0 = len
	while len0 > 0 do
		table.insert(lent, 1, len0 % 256)
		len0 = math.floor(len0 / 256)
	end
	table.insert(lent, #lent)		-- #lent < 255

	-- put \0 bytes. Expected length %4 == 0 , where length = file length + length of file length
	local deltafile = (4 - len % 4)
	local deltatable = #lent % 4
	local lendelta = (deltafile < deltatable) and (4 - deltatable + deltafile) or deltafile - deltatable
	for i = 1, lendelta do
		table.insert(lent, 1, 0)
	end

	raw = raw .. string.char(unpack(lent))

	local encoded = encodeString(
		"tea",
		raw,
		{ key = KEY }
	)

	local file = File.new("encoded")
	file:write(encoded)
	file:close()


	-- DECODE
	local decoded = decodeString(
		"tea",
		encoded,
		{ key = KEY }
	)

	local declen = #decoded
	local lentlen = decoded:sub(declen, declen):byte(1)
	local lent = 0
	for i = 1, lentlen do
		lent = lent + decoded:sub(declen - i, declen - i):byte(1) * 256 ^ (i - 1)
	end

	local decodedcut = decoded:sub(1, lent)

	local file = File.new("decoded.txt")
	file:write(decodedcut)
	file:close()

	outputDebugString("Ready!")
end)