module:set_global();

local array = require "util.array";

local max_buffer_len = module:get_option_number("multiplex_buffer_size", 1024);

local portmanager = require "core.portmanager";

local available_services = {};

local service_by_protocol = {};

local available_protocols = array();

local function add_service(service)

	local multiplex_pattern = service.multiplex and service.multiplex.pattern;

	local protocol_name = service.multiplex and service.multiplex.protocol;

	if protocol_name then

		module:log("debug", "Adding multiplex service %q with protocol %q", service.name, protocol_name);

		service_by_protocol[protocol_name] = service;

		available_protocols:push(protocol_name);

	end

	if multiplex_pattern then

		module:log("debug", "Adding multiplex service %q with pattern %q", service.name, multiplex_pattern);

		available_services[service] = multiplex_pattern;

	elseif not protocol_name then

		module:log("debug", "Service %q is not multiplex-capable", service.name);

	end

	module:log("info", "available_protocols = %q", available_protocols);

end

module:hook("service-added", function (event) add_service(event.service); end);

module:hook("service-removed", function (event)

	available_services[event.service] = nil;

	if event.service.multiplex and event.service.multiplex.protocol then

		available_protocols:filter(function (p) return p ~= event.service.multiplex.protocol end);

		service_by_protocol[event.service.multiplex.protocol] = nil;

	end

end);

for _, services in pairs(portmanager.get_registered_services()) do

	for _, service in ipairs(services) do

		add_service(service);

	end

end

local buffers = {};

local listener = { default_mode = "*a" };

function listener.onconnect(conn)

	local sock = conn:socket();

	if sock.getalpn then

		local selected_proto = sock:getalpn();

		local service = service_by_protocol[selected_proto];

		if service then

			local next_listener = service.listener;

			conn:setlistener(next_listener);

			local onconnect = next_listener.onconnect;

			if onconnect then return onconnect(conn) end

		end

	end

end

function listener.onincoming(conn, data)

	if not data then return; end

	local buf = buffers[conn];

	buf = buf and buf..data or data;

	for service, multiplex_pattern in pairs(available_services) do

		if buf:match(multiplex_pattern) then

			module:log("debug", "Routing incoming connection to %s", service.name);

			local next_listener = service.listener;

			conn:setlistener(next_listener);

			local onconnect = next_listener.onconnect;

			if onconnect then onconnect(conn) end

			return next_listener.onincoming(conn, buf);

		end

	end

	if #buf > max_buffer_len then -- Give up

		conn:close();

	else

		buffers[conn] = buf;

	end

end

function listener.ondisconnect(conn)

	buffers[conn] = nil; -- warn if no buffer?

end

listener.ondetach = listener.ondisconnect;

module:provides("net", {

	name = "multiplex";

	config_prefix = "";

	listener = listener;

});

module:provides("net", {

	name = "multiplex_ssl";

	config_prefix = "ssl";

	encryption = "ssl";

	ssl_config = {

		alpn = function ()

			return available_protocols;

		end;

	};

	listener = listener;

});