local new_sasl = require "util.sasl".new;

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

local ldap_server = module:get_option_string("ldap_server", "localhost");

local ldap_rootdn = module:get_option_string("ldap_rootdn", "");

local ldap_password = module:get_option_string("ldap_password", "");

local ldap_tls = module:get_option_boolean("ldap_tls");

local ldap_scope = module:get_option_string("ldap_scope", "onelevel");

local ldap_filter = module:get_option_string("ldap_filter", "(uid=%s)");

local ldap_base = assert(module:get_option_string("ldap_base"), "ldap_base is a required option for ldap");

local lualdap = require "lualdap";

local ld = assert(lualdap.open_simple(ldap_server, ldap_rootdn, ldap_password, ldap_tls));

module.unload = function() ld:close(); end

local function ldap_filter_escape(s) return (s:gsub("[\\*\\(\\)\\\\%z]", function(c) return ("\\%02x"):format(c:byte()) end)); end

local function get_user(username)

	module:log("debug", "get_user(%q)", username);

	return ld:search({

		base = ldap_base;

		scope = ldap_scope;

		filter = ldap_filter:format(ldap_filter_escape(username));

	})();

end

local provider = {};

function provider.get_password(username)

	local dn, attr = get_user(username);

	if dn and attr then

		return attr.userPassword;

	end

end

function provider.test_password(username, password)

	return provider.get_password(username) == password;

end

function provider.user_exists(username)

	return not not get_user(username);

end

function provider.get_sasl_handler()

	return new_sasl(module.host, {

		plain = function(sasl, username)

			local password = provider.get_password(username);

			if not password then return "", nil; end

			return password, true;

		end

	});

end

module:provides("auth", provider);