-- Prosody IM

-- Copyright (C) 2008-2009 Matthew Wild

-- Copyright (C) 2008-2009 Waqas Hussain

-- 

-- This project is MIT/X11 licensed. Please see the

-- COPYING file in the source package for more information.

--

local server = require "net.server";

local dns = require "net.dns";

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

local coroutine, tostring, pcall = coroutine, tostring, pcall;

module "adns"

function lookup(handler, qname, qtype, qclass)

	return coroutine.wrap(function (peek)

				if peek then

					log("debug", "Records for %s already cached, using those...", qname);

					handler(peek);

					return;

				end

				log("debug", "Records for %s not in cache, sending query (%s)...", qname, tostring(coroutine.running()));

				dns.query(qname, qtype, qclass);

				coroutine.yield({ qclass or "IN", qtype or "A", qname, coroutine.running()}); -- Wait for reply

				log("debug", "Reply for %s (%s)", qname, tostring(coroutine.running()));

				local ok, err = pcall(handler, dns.peek(qname, qtype, qclass));

				if not ok then

					log("debug", "Error in DNS response handler: %s", tostring(err));

				end

			end)(dns.peek(qname, qtype, qclass));

end

function cancel(handle, call_handler)

	log("warn", "Cancelling DNS lookup for %s", tostring(handle[3]));

	dns.cancel(handle);

	if call_handler then

		coroutine.resume(handle[4]);

	end

end

function new_async_socket(sock)

	local newconn = {};

	local listener = {};

	function listener.incoming(conn, data)

		dns.feed(sock, data);

	end

	function listener.disconnect()

	end

	newconn.handler, newconn._socket = server.wrapclient(sock, "dns", 53, listener);

	newconn.handler.settimeout = function () end

	newconn.handler.setsockname = function (_, ...) return sock:setsockname(...); end

	newconn.handler.setpeername = function (_, ...) local ret = sock:setpeername(...); _.setsend(sock.send); return ret; end

	newconn.handler.connect = function (_, ...) return sock:connect(...) end	

	newconn.handler.send = function (_, data) _.write(data); return _.sendbuffer(); end	

	return newconn.handler;

end

dns:socket_wrapper_set(new_async_socket);

return _M;