local format = string.format;

local send_s2s = require "core.s2smanager".send_to_host;

local s2s_make_authenticated = require "core.s2smanager".make_authenticated;

local s2s_verify_dialback = require "core.s2smanager".verify_dialback;

local log = require "util.logger".init("mod_dialback");

local xmlns_dialback = "jabber:server:dialback";

add_handler({"s2sin_unauthed", "s2sin"}, "verify", xmlns_dialback,

		function (origin, stanza)

			-- We are being asked to verify the key, to ensure it was generated by us

			log("debug", "verifying dialback key...");

			local attr = stanza.attr;

			-- FIXME: Grr, ejabberd breaks this one too?? it is black and white in XEP-220 example 34

			--if attr.from ~= origin.to_host then error("invalid-from"); end

			local type;

			if s2s_verify_dialback(attr.id, attr.from, attr.to, stanza[1]) then

				type = "valid"

			else

				type = "invalid"

				log("warn", "Asked to verify a dialback key that was incorrect. An imposter is claiming to be %s?", attr.to);

			end

			origin.sends2s(format("<db:verify from='%s' to='%s' id='%s' type='%s'>%s</db:verify>", attr.to, attr.from, attr.id, type, stanza[1]));		

		end);

add_handler("s2sin_unauthed", "result", xmlns_dialback,

		function (origin, stanza)

			-- he wants to be identified through dialback

			-- We need to check the key with the Authoritative server

			local attr = stanza.attr;

			local attr = stanza.attr;

			origin.from_host = attr.from;

			origin.to_host = attr.to;

			origin.dialback_key = stanza[1];

			log("debug", "asking %s if key %s belongs to them", origin.from_host, origin.dialback_key);

			send_s2s(origin.to_host, origin.from_host, format("<db:verify from='%s' to='%s' id='%s'>%s</db:verify>", origin.to_host, origin.from_host, origin.streamid, origin.dialback_key));

			hosts[origin.from_host].dialback_verifying = origin;

		end);

add_handler({ "s2sout_unauthed", "s2sout" }, "verify", xmlns_dialback,

		function (origin, stanza)

			if origin.dialback_verifying then

				local valid;

				local attr = stanza.attr;

				if attr.type == "valid" then

					s2s_make_authenticated(origin.dialback_verifying);

					valid = "valid";

				else

					-- Warn the original connection that is was not verified successfully

					log("warn", "dialback for "..(origin.dialback_verifying.from_host or "(unknown)").." failed");

					valid = "invalid";

				end

				origin.dialback_verifying.sends2s(format("<db:result from='%s' to='%s' id='%s' type='%s'>%s</db:result>", attr.from, attr.to, attr.id, valid, origin.dialback_verifying.dialback_key));

			end

		end);

add_handler({ "s2sout_unauthed", "s2sout" }, "result", xmlns_dialback,

		function (origin, stanza)

			if stanza.attr.type == "valid" then

				s2s_make_authenticated(origin);

			else

				-- FIXME

				error("dialback failed!");

			end

		end);