-- 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 st = require "util.stanza";
local t_concat = table.concat;

local secure_auth_only = module:get_option("c2s_require_encryption") or module:get_option("require_encryption");

local sessionmanager = require "core.sessionmanager";
local usermanager = require "core.usermanager";
local nodeprep = require "util.encodings".stringprep.nodeprep;
local resourceprep = require "util.encodings".stringprep.resourceprep;

module:add_feature("jabber:iq:auth");
module:add_event_hook("stream-features", function (session, features)
	if secure_auth_only and not session.secure then
		-- Sorry, not offering to insecure streams!
		return;
	elseif not session.username then
		features:tag("auth", {xmlns='http://jabber.org/features/iq-auth'}):up();
	end
end);

module:add_iq_handler("c2s_unauthed", "jabber:iq:auth", 
		function (session, stanza)
			if secure_auth_only and not session.secure then
				session.send(st.error_reply(stanza, "modify", "not-acceptable", "Encryption (SSL or TLS) is required to connect to this server"));
				return true;
			end
			
			local username = stanza.tags[1]:child_with_name("username");
			local password = stanza.tags[1]:child_with_name("password");
			local resource = stanza.tags[1]:child_with_name("resource");
			if not (username and password and resource) then
				local reply = st.reply(stanza);
				session.send(reply:query("jabber:iq:auth")
					:tag("username"):up()
					:tag("password"):up()
					:tag("resource"):up());
			else
				username, password, resource = t_concat(username), t_concat(password), t_concat(resource);
				username = nodeprep(username);
				resource = resourceprep(resource)
				local reply = st.reply(stanza);
				if usermanager.validate_credentials(session.host, username, password) then
					-- Authentication successful!
					local success, err = sessionmanager.make_authenticated(session, username);
					if success then
						local err_type, err_msg;
						success, err_type, err, err_msg = sessionmanager.bind_resource(session, resource);
						if not success then
							session.send(st.error_reply(stanza, err_type, err, err_msg));
							session.username, session.type = nil, "c2s_unauthed"; -- FIXME should this be placed in sessionmanager?
							return true;
						elseif resource ~= session.resource then -- server changed resource, not supported by legacy auth
							session.send(st.error_reply(stanza, "cancel", "conflict", "The requested resource could not be assigned to this session."));
							session:close(); -- FIXME undo resource bind and auth instead of closing the session?
							return true;
						end
					end
					session.send(st.reply(stanza));
				else
					session.send(st.error_reply(stanza, "auth", "not-authorized"));
				end
			end
			return true;
		end);