require "base64"

function sasl:new_plain(onAuth, onSuccess, onFail, onWrite)

	local object = { mechanism = "PLAIN", onAuth = onAuth, onSuccess = onSuccess, onFail = onFail,

	 				onWrite = onWrite}

	local challenge = base64.encode("");

	onWrite(stanza.stanza("challenge", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"}):text(challenge))

	object.feed = 	function(self, stanza)

						if (stanza.name ~= "response") then self.onFail() end

						if (stanza.attr.xmlns ~= "urn:ietf:params:xml:ns:xmpp-sasl") then self.onFail() end

						local response = base64.decode(stanza.tag[1])

						local authorization = string.match(response, [[([^&\0]+)]])

						local authentication = string.match(response, [[\0([^&\0]+)\0]])

						local password = string.match(response, [[\0[^&\0]+\0([^&\0]+)]])

						if self.onAuth(authorization, password) == true then

							self.onWrite(stanza.stanza("success", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"}))

							self.onSuccess()

						else

							self.onWrite(stanza.stanza("failure", {xmlns = "urn:ietf:params:xml:ns:xmpp-sasl"}):tag("temporary-auth-failure"));

						end

					end

	return object

end

function sasl:new(mechanism, onAuth, onSuccess, onFail, onWrite)

	local object

	if mechanism == "PLAIN" then object = new_plain(onAuth, onSuccess, onFail, onWrite)

	else onFail()

	end

	return object

end

module "sasl"