local st = require "util.stanza";

local jid = require "util.jid";

local id = require "util.id";

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

local xmlns_quick_resp = "urn:xmpp:tmp:quick-response";

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

local help = name..[[

Commands:

- `help` - this help message

- `list` - list available nodes

- `subscriptions` - list nodes you are subscribed to

- `subscribe node` - subscribe to a node

- `unsubscribe node` - unsubscribe from a node]];

if pubsub.get_last_item then -- COMPAT not available in 0.10

	help = help ..  "\n- `last node` - send the last item (again)"

end

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

	local stanza = 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):up();

		reply:tag("response", { xmlns = xmlns_quick_resp, value = "list", }):up();

		reply:tag("response", { xmlns = xmlns_quick_resp, value = "subscriptions", }):up();

	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 == "subscriptions" then

		local ok, subs = pubsub:get_subscriptions(nil, from, from);

		if not ok then

			reply:body(subs);

		elseif #subs == 0 then

			reply:body("You are not subscribed to anything from this pubsub service");

		else

			local response = {};

			for i = 1, #subs do

				response[i] = string.format("- `%s`", subs[i].node);

				reply:tag("response", { xmlns = xmlns_quick_resp, value = "unsubscribe "..subs[i].node, }):up();

				reply:tag("response", { xmlns = xmlns_quick_resp, value = "last "..subs[i].node, }):up();

			end

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

		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);

	elseif command == "last" and pubsub.get_last_item then

		local ok, item_id, item = pubsub:get_last_item(node_arg, from);

		if not ok then

			reply:body(item_id); -- err message

		elseif not item_id then

			reply:body("node is empty");

		else

			pubsub.config.broadcaster("items", node_arg, {

				[from] = { ["pubsub#include_body"] = true }

			}, item, nil, pubsub.nodes[node_arg]);

			reply:body("OK");

		end

	else

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

		reply:tag("response", { xmlns = xmlns_quick_resp, value = "help", }):up();

	end

	reply:reset();

	if stanza:get_child("no-copy", "urn:xmpp:hints") then

		reply:tag("no-copy", { xmlns = "urn:xmpp:hints" }):up();

	end

	if stanza:get_child("no-store", "urn:xmpp:hints") then

		reply:tag("no-store", { xmlns = "urn:xmpp:hints" }):up();

	end

	module:send(reply);

	return true;

end);