local config = require "core.configmanager";

local certmanager = require "core.certmanager";

local server = require "net.server";

local socket = require "socket";

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

local multitable = require "util.multitable";

local set = require "util.set";

local table = table;

local setmetatable, rawset, rawget = setmetatable, rawset, rawget;

local type, tonumber, tostring, ipairs = type, tonumber, tostring, ipairs;

local prosody = prosody;

local fire_event = prosody.events.fire_event;

local _ENV = nil;

-- luacheck: std none

--- Config

local default_interfaces = { };

local default_local_interfaces = { };

if config.get("*", "use_ipv4") ~= false then

	table.insert(default_interfaces, "*");

	table.insert(default_local_interfaces, "127.0.0.1");

end

if socket.tcp6 and config.get("*", "use_ipv6") ~= false then

	table.insert(default_interfaces, "::");

	table.insert(default_local_interfaces, "::1");

end

local default_mode = config.get("*", "network_default_read_size") or 4096;

--- Private state

-- service_name -> { service_info, ... }

local services = setmetatable({}, { __index = function (t, k) rawset(t, k, {}); return rawget(t, k); end });

-- service_name, interface (string), port (number)

local active_services = multitable.new();

--- Private helpers

local function error_to_friendly_message(service_name, port, err) --luacheck: ignore 212/service_name

	local friendly_message = err;

	if err:match(" in use") then

		-- FIXME: Use service_name here

		if port == 5222 or port == 5223 or port == 5269 then

			friendly_message = "check that Prosody or another XMPP server is "

				.."not already running and using this port";

		elseif port == 80 or port == 81 then

			friendly_message = "check that a HTTP server is not already using "

				.."this port";

		elseif port == 5280 then

			friendly_message = "check that Prosody or a BOSH connection manager "

				.."is not already running";

		else

			friendly_message = "this port is in use by another application";

		end

	elseif err:match("permission") then

		friendly_message = "Prosody does not have sufficient privileges to use this port";

	end

	return friendly_message;

end

--- Public API

local function activate(service_name)

	local service_info = services[service_name][1];

	if not service_info then

		return nil, "Unknown service: "..service_name;

	end

	local listener = service_info.listener;

	local config_prefix = (service_info.config_prefix or service_name).."_";

	if config_prefix == "_" then

		config_prefix = "";

	end

	local bind_interfaces = config.get("*", config_prefix.."interfaces")

		or config.get("*", config_prefix.."interface") -- COMPAT w/pre-0.9

		or (service_info.private and (config.get("*", "local_interfaces") or default_local_interfaces))

		or config.get("*", "interfaces")

		or config.get("*", "interface") -- COMPAT w/pre-0.9

		or listener.default_interface -- COMPAT w/pre0.9

		or default_interfaces

	bind_interfaces = set.new(type(bind_interfaces)~="table" and {bind_interfaces} or bind_interfaces);

	local bind_ports = config.get("*", config_prefix.."ports")

		or service_info.default_ports

		or {service_info.default_port

		    or listener.default_port -- COMPAT w/pre-0.9

		   }

	bind_ports = set.new(type(bind_ports) ~= "table" and { bind_ports } or bind_ports );

	local mode, ssl = listener.default_mode or default_mode;

	local hooked_ports = {};

	for interface in bind_interfaces do

		for port in bind_ports do

			local port_number = tonumber(port);

			if not port_number then

				log("error", "Invalid port number specified for service '%s': %s", service_info.name, tostring(port));

			elseif #active_services:search(nil, interface, port_number) > 0 then

				log("error", "Multiple services configured to listen on the same port ([%s]:%d): %s, %s", interface, port,

					active_services:search(nil, interface, port)[1][1].service.name or "<unnamed>", service_name or "<unnamed>");

			else

				local err;

				-- Create SSL context for this service/port

				if service_info.encryption == "ssl" then

					local global_ssl_config = config.get("*", "ssl") or {};

					local prefix_ssl_config = config.get("*", config_prefix.."ssl") or global_ssl_config;

					log("debug", "Creating context for direct TLS service %s on port %d", service_info.name, port);

					ssl, err = certmanager.create_context(service_info.name.." port "..port, "server",

						prefix_ssl_config[interface],

						prefix_ssl_config[port],

						prefix_ssl_config,

						service_info.ssl_config or {},

						global_ssl_config[interface],

						global_ssl_config[port]);

					if not ssl then

						log("error", "Error binding encrypted port for %s: %s", service_info.name,

							error_to_friendly_message(service_name, port_number, err) or "unknown error");

					end

				end

				if not err then

					-- Start listening on interface+port

					local handler, err = server.addserver(interface, port_number, listener, mode, ssl);

					if not handler then

						log("error", "Failed to open server port %d on %s, %s", port_number, interface,

							error_to_friendly_message(service_name, port_number, err));

					else

						table.insert(hooked_ports, "["..interface.."]:"..port_number);

						log("debug", "Added listening service %s to [%s]:%d", service_name, interface, port_number);

						active_services:add(service_name, interface, port_number, {

							server = handler;

							service = service_info;

						});

					end

				end

			end

		end

	end

	log("info", "Activated service '%s' on %s", service_name,

		#hooked_ports == 0 and "no ports" or table.concat(hooked_ports, ", "));

	return true;

end

local close; -- forward declaration

local function deactivate(service_name, service_info)

	for name, interface, port, n, active_service --luacheck: ignore 213/name 213/n

		in active_services:iter(service_name or service_info and service_info.name, nil, nil, nil) do

		if service_info == nil or active_service.service == service_info then

			close(interface, port);

		end

	end

	log("info", "Deactivated service '%s'", service_name or service_info.name);

end

local function register_service(service_name, service_info)

	table.insert(services[service_name], service_info);

	if not active_services:get(service_name) then

		log("debug", "No active service for %s, activating...", service_name);

		local ok, err = activate(service_name);

		if not ok then

			log("error", "Failed to activate service '%s': %s", service_name, err or "unknown error");

		end

	end

	fire_event("service-added", { name = service_name, service = service_info });

	return true;

end

local function unregister_service(service_name, service_info)

	log("debug", "Unregistering service: %s", service_name);

	local service_info_list = services[service_name];

	for i, service in ipairs(service_info_list) do

		if service == service_info then

			table.remove(service_info_list, i);

		end

	end

	deactivate(nil, service_info);

	if #service_info_list > 0 then -- Other services registered with this name

		activate(service_name); -- Re-activate with the next available one

	end

	fire_event("service-removed", { name = service_name, service = service_info });

end

local get_service_at -- forward declaration

function close(interface, port)

	local service, service_server = get_service_at(interface, port);

	if not service then

		return false, "port-not-open";

	end

	service_server:close();

	active_services:remove(service.name, interface, port);

	log("debug", "Removed listening service %s from [%s]:%d", service.name, interface, port);

	return true;

end

function get_service_at(interface, port)

	local data = active_services:search(nil, interface, port)[1][1];

	return data.service, data.server;

end

local function get_service(service_name)

	return (services[service_name] or {})[1];

end

local function get_active_services()

	return active_services;

end

local function get_registered_services()

	return services;

end

-- Event handlers

prosody.events.add_handler("item-added/net-provider", function (event)

	local item = event.item;

	register_service(item.name, item);

end);

prosody.events.add_handler("item-removed/net-provider", function (event)

	local item = event.item;

	unregister_service(item.name, item);

end);

return {

	activate = activate;

	deactivate = deactivate;

	register_service = register_service;

	unregister_service = unregister_service;

	close = close;

	get_service_at = get_service_at;

	get_service = get_service;

	get_active_services = get_active_services;

	get_registered_services = get_registered_services;

};