--

--	tek.class.cgi - tek cgi class

--	Written by Timm S. Mueller <tmueller at neoscientists.org>

--	See copyright notice in COPYRIGHT

--

local type, tonumber = type, tonumber

local insert, concat, char = table.insert, table.concat, string.char

module "tek.class.cgi"

_VERSION = "CGI 1.3"

-------------------------------------------------------------------------------

--	encodeurl: encode string to url; optionally specify a string with a

--	set of characters that should be left unmodified, from: $&+,/:;=?@

-------------------------------------------------------------------------------

local function encodefunc(c)

	return ("%%%02x"):format(c:byte())

end

function encodeurl(s, excl)

	-- reserved chars with special meaning:

	local matchset = "$&+,/:;=?@"

	if excl == true then

		matchset = ""

	elseif excl and type(excl) == "string" then

		matchset = matchset:gsub("[" .. excl:gsub(".", "%%%1") .. "]", "")

	end

	-- unsafe chars are always substituted:

	matchset = matchset .. '"<>#%{}|\\^~[]`]'

	matchset = "[%z\001-\032\127-\255" .. matchset:gsub(".", "%%%1") .. "]"

	return s:gsub(matchset, encodefunc)

end

-------------------------------------------------------------------------------

--	decodeurl

-------------------------------------------------------------------------------

local function decodefunc(h)

	return char(tonumber(h, 16))

end

function decodeurl(s)

	return (s:gsub("+", " ")):gsub("%%(%x%x)", decodefunc)

end