local st, jid, set = require "util.stanza", require "util.jid", require "util.set";

local admins = set.new(config.get(module:get_host(), "core", "admins"));

function handle_announcement(data)

	local origin, stanza = data.origin, data.stanza;

	local host, resource = select(2, jid.split(stanza.attr.to));

	if resource ~= "announce/online" then

		return; -- Not an announcement

	end

		-- Not an admin? Not allowed!

		module:log("warn", "Non-admin %s tried to send server announcement", tostring(jid.bare(origin.full_jid)));

		origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));

		return;

	end

	module:log("info", "Sending server announcement to all online users");

	local host_session = hosts[host];

	local message = st.clone(stanza);

	message.attr.type = "headline";

	message.attr.from = host;

	local c = 0;

	for user in pairs(host_session.sessions) do

		c = c + 1;

		message.attr.to = user.."@"..host;

		core_post_stanza(host_session, message);

	end

	module:log("info", "Announcement sent to %d online users", c);

	return true;

end

module:hook("message/host", handle_announcement);