--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_muc_gc10/mod_muc_gc10.lua	Tue Mar 27 10:51:25 2018 +0200
@@ -0,0 +1,58 @@
+local jid_bare = require "util.jid".bare;
+local st = require "util.stanza";
+
+local rooms = module:depends"muc".rooms;
+
+module:hook("presence/full", function (event)
+	local stanza, origin = event.stanza, event.origin;
+	if stanza.attr.type ~= nil then return end
+
+	local muc_x = stanza:get_child("x", "http://jabber.org/protocol/muc");
+
+	local room_jid = jid_bare(stanza.attr.to);
+	local room = rooms[room_jid];
+	if not room then
+		if muc_x then
+			-- Normal MUC creation
+		else
+			module:log("info", "GC 1.0 room creation from %s", stanza.attr.from);
+			module:send(st.iq({type="get",id=module.name,from=module.host,to=stanza.attr.from}):query("jabber:iq:version"));
+		end
+		return;
+	end
+	local current_nick = room._jid_nick[stanza.attr.from];
+
+	if current_nick then
+		-- present
+		if muc_x then
+			module:log("info", "MUC desync with %s", stanza.attr.from);
+			module:send(st.iq({type="get",id=module.name,from=module.host,to=stanza.attr.from}):query("jabber:iq:version"));
+		else
+			-- normal presence update
+		end
+	else
+		-- joining
+		if muc_x then
+			-- normal join
+		else
+			module:log("info", "GC 1.0 join from %s", stanza.attr.from);
+			module:send(st.iq({type="get",id=module.name,from=module.host,to=stanza.attr.from}):query("jabber:iq:version"));
+		end
+	end
+end);
+
+module:hook("iq-result/host/"..module.name, function (event)
+	local stanza, origin = event.stanza, event.origin;
+	local version = stanza:get_child("query", "jabber:iq:version");
+	if not version then
+		module:log("info", "%s replied with an invalid version reply: %s", stanza.attr.from, tostring(stanza));
+		return true;
+	end
+	module:log("info", "%s is running: %s %s", stanza.attr.from, version:get_child_text("name"), version:get_child_text("version"));
+end);
+
+module:hook("iq-error/host/"..module.name, function (event)
+	local stanza, origin = event.stanza, event.origin;
+	module:log("info", "%s replied with an error: %s %s", stanza.attr.from, stanza:get_error());
+	return true;
+end);