local now = os.time;

local s2smanager = require "core.s2smanager";

local timer = require "util.timer";

local s2s_sessions = setmetatable({}, { __mode = "kv" });

local idle_timeout = module:get_option("s2s_idle_timeout") or 300;

local check_interval = math.ceil(idle_timeout * 0.75);

local function install_checks(session)

	if not session.last_received_time then

		session.last_received_time = now();

		if session.direction == "incoming" then

			local _data = session.data;

			function session.data(conn, data)

				session.last_received_time = now();

				return _data(conn, data);

			end

		else

			local _sends2s = session.sends2s;

			function session.sends2s(data)

				session.last_received_time = now();

				return _sends2s(data);

			end

		end

		s2s_sessions[session] = true;

	end

end

module:hook("s2s-authenticated", function (event)

	install_checks(event.session);

end);

function check_idle_sessions(time)

	time = time or now();

	for session in pairs(s2s_sessions) do

		local last_received_time = session.last_received_time;

		if last_received_time and time - last_received_time > idle_timeout then

			module:log("debug", "Closing idle connection %s->%s",

				session.from_host or "(unknown)", session.to_host or "(unknown)");

			session:close(); -- Close-on-idle isn't an error

			s2s_sessions[session] = nil;

		end

	end

	return check_interval;

end

timer.add_task(check_interval, check_idle_sessions);

function module.save()

	return { s2s_sessions = s2s_sessions };

end

function module.restore(data)

	s2s_sessions = setmetatable(data.s2s_sessions or {}, { __mode = "kv" });

end