local st = require "util.stanza";

local jid = require "util.jid";

local id = require "util.id";

local pubsub = module:depends "pubsub".service;

local name = module:get_option_string("name", "PubSub Service on "..module.host);

local help = name..[[

Commands:

- `help` - this help message

- `list` - list available nodes

- `subscribe node` - subscribe to a node

- `unsubscribe node` - unsubscribe from a node

]];

module:hook("message/host", function (event)

	local origin, stanza = event.origin, event.stanza;

	local body = stanza:get_child_text("body");

	if not body then return end -- bail out

	local from = stanza.attr.from;

	local reply = st.reply(stanza);

	reply.attr.id = id.medium();

	local command, node_arg = body:match("^(%a+)%s+(.*)");

	command = (command or body):lower();

	if command == "help" then

		reply:body(help);

	elseif command == "list" then

		local ok, nodes = pubsub:get_nodes(from);

		if ok then

			local list = {};

			for node, node_obj in pairs(nodes) do

				table.insert(list, ("- `%s` %s"):format(node, node_obj.config.title or ""));

			end

			reply:body(table.concat(list, "\n"));

		else

			reply:body(nodes);

		end

	elseif command == "subscribe" then

		local ok, err = pubsub:add_subscription(node_arg, from, jid.bare(from), { ["pubsub#include_body"] = true });

		reply:body(ok and "OK" or err);

	elseif command == "unsubscribe" then

		local ok, err = pubsub:remove_subscription(node_arg, from, jid.bare(from));

		reply:body(ok and "OK" or err);

	else

		reply:body("Unknown command. `help` to list commands.");

	end

	origin.send(reply);

	return true;

end);