-- Prosody IM

-- Copyright (C) 2008-2010 Matthew Wild

-- Copyright (C) 2008-2010 Waqas Hussain

--

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

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

--

local function softreq(...) local ok, lib =  pcall(require, ...); if ok then return lib; else return nil, lib; end end

-- Required to be able to find packages installed with luarocks

if not softreq "luarocks.loader" then -- LuaRocks 2.x

	softreq "luarocks.require"; -- LuaRocks <1.x

end

local function missingdep(name, sources, msg, err) -- luacheck: ignore err

	-- TODO print something about the underlying error, useful for debugging

	print("");

	print("**************************");

	print("Prosody was unable to find "..tostring(name));

	print("This package can be obtained in the following ways:");

	print("");

	for _, row in ipairs(sources) do

		print(string.format("%15s | %s", table.unpack(row)));

	end

	print("");

	print(msg or (name.." is required for Prosody to run, so we will now exit."));

	print("More help can be found on our website, at https://prosody.im/doc/depends");

	print("**************************");

	print("");

end

local function check_dependencies()

	if _VERSION < "Lua 5.2" then

		print "***********************************"

		print("Unsupported Lua version: ".._VERSION);

		print("At least Lua 5.2 is required.");

		print "***********************************"

		return false;

	end

	local fatal;

	local lxp, err = softreq "lxp"

	if not lxp then

		missingdep("luaexpat", {

				{ "Debian/Ubuntu", "sudo apt install lua-expat" };

				{ "luarocks", "luarocks install luaexpat" };

				{ "Source", "http://matthewwild.co.uk/projects/luaexpat/" };

			}, nil, err);

		fatal = true;

	end

	local socket, err = softreq "socket"

	if not socket then

		missingdep("luasocket", {

				{ "Debian/Ubuntu", "sudo apt install lua-socket" };

				{ "luarocks", "luarocks install luasocket" };

				{ "Source", "http://www.tecgraf.puc-rio.br/~diego/professional/luasocket/" };

			}, nil, err);

		fatal = true;

	elseif not socket.tcp4 then

		-- COMPAT LuaSocket before being IP-version agnostic

		socket.tcp4 = socket.tcp;

		socket.udp4 = socket.udp;

	end

	local lfs, err = softreq "lfs"

	if not lfs then

		missingdep("luafilesystem", {

			{ "luarocks", "luarocks install luafilesystem" };

			{ "Debian/Ubuntu", "sudo apt install lua-filesystem" };

			{ "Source", "http://www.keplerproject.org/luafilesystem/" };

		}, nil, err);

		fatal = true;

	end

	local ssl, err = softreq "ssl"

	if not ssl then

		missingdep("LuaSec", {

				{ "Debian/Ubuntu", "sudo apt install lua-sec" };

				{ "luarocks", "luarocks install luasec" };

				{ "Source", "https://github.com/brunoos/luasec" };

			}, nil, err);

	end

	local bit, err = softreq"prosody.util.bitcompat";

	if not bit then

		missingdep("lua-bitops", {

			{ "Debian/Ubuntu", "sudo apt install lua-bitop" };

			{ "luarocks", "luarocks install luabitop" };

			{ "Source", "http://bitop.luajit.org/" };

		}, "WebSocket support will not be available", err);

	end

	local unbound, err = softreq"lunbound"; -- luacheck: ignore 211/err

	if not unbound then

		missingdep("lua-unbound", {

				{ "Debian/Ubuntu", "sudo apt install lua-unbound" };

				{ "luarocks", "luarocks install luaunbound" };

				{ "Source", "https://www.zash.se/luaunbound.html" };

			}, "Old DNS resolver library will be used", err);

	else

		package.preload["prosody.net.adns"] = function ()

			local ub = require "prosody.net.unbound";

			return ub;

		end

	end

	local encodings, err = softreq "prosody.util.encodings"

	if not encodings then

		if err:match("module '[^']*' not found") then

			missingdep("prosody.util.encodings", {

				{ "Windows", "Make sure you have encodings.dll from the Prosody distribution in util/" };

				{ "GNU/Linux", "Run './configure' and 'make' in the Prosody source directory to build util/encodings.so" };

			});

		else

			print "***********************************"

			print("util/encodings couldn't be loaded. Check that you have a recent version of libidn");

			print ""

			print("The full error was:");

			print(err)

			print "***********************************"

		end

		fatal = true;

	end

	local hashes, err = softreq "prosody.util.hashes"

	if not hashes then

		if err:match("module '[^']*' not found") then

			missingdep("prosody.util.hashes", {

				{ "Windows", "Make sure you have hashes.dll from the Prosody distribution in util/" };

				{ "GNU/Linux", "Run './configure' and 'make' in the Prosody source directory to build util/hashes.so" };

			});

		else

			print "***********************************"

			print("util/hashes couldn't be loaded. Check that you have a recent version of OpenSSL (libcrypto in particular)");

			print ""

			print("The full error was:");

			print(err)

			print "***********************************"

		end

		fatal = true;

	end

	return not fatal;

end

local function log_warnings()

	if _VERSION > "Lua 5.4" then

		prosody.log("warn", "Support for %s is experimental, please report any issues", _VERSION);

	elseif _VERSION < "Lua 5.2" then

		prosody.log("warn", "%s support is deprecated, upgrade as soon as possible", _VERSION);

	end

	local ssl = softreq"ssl";

	if ssl then

		local major, minor, veryminor, patched = ssl._VERSION:match("(%d+)%.(%d+)%.?(%d*)(M?)");

		if not major or ((tonumber(major) == 0 and (tonumber(minor) or 0) <= 3 and (tonumber(veryminor) or 0) <= 2) and patched ~= "M") then

			prosody.log("error", "This version of LuaSec contains a known bug that causes disconnects, see https://prosody.im/doc/depends");

		end

	end

	local lxp = softreq"lxp";

	if lxp then

		if not pcall(lxp.new, { StartDoctypeDecl = false }) then

			prosody.log("error", "The version of LuaExpat on your system leaves Prosody "

				.."vulnerable to denial-of-service attacks. You should upgrade to "

				.."LuaExpat 1.3.0 or higher as soon as possible. See "

				.."https://prosody.im/doc/depends#luaexpat for more information.");

		end

		if not lxp.new({}).getcurrentbytecount then

			prosody.log("error", "The version of LuaExpat on your system does not support "

				.."stanza size limits, which may leave servers on untrusted "

				.."networks (e.g. the internet) vulnerable to denial-of-service "

				.."attacks. You should upgrade to LuaExpat 1.3.0 or higher as "

				.."soon as possible. See "

				.."https://prosody.im/doc/depends#luaexpat for more information.");

		end

	end

end

return {

	softreq = softreq;

	missingdep = missingdep;

	check_dependencies = check_dependencies;

	log_warnings = log_warnings;

};