view mod_muc_dicebot/mod_muc_dicebot.lua @ 5401:c8d04ac200fc

mod_http_oauth2: Reject loopback URIs as client_uri This really should be a proper website with info, https://localhost is not good enough. Ideally we'd validate that it's got proper DNS and is actually reachable, but triggering HTTP or even DNS lookups seems like it would carry abuse potential that would best to avoid.
author Kim Alvefur <zash@zash.se>
date Tue, 02 May 2023 16:20:55 +0200
parents 785389a2d2b3
children
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local muc = module:depends("muc");
local rand = require"util.random";

local s_match = string.match;
local s_gmatch = string.gmatch;
local t_insert = table.insert;
local t_concat = table.concat;

local rooms = module:get_option_set("muc_dicebot_rooms", nil);
local xmlns_nick = "http://jabber.org/protocol/nick";

local function is_room_affected(roomjid)
	return not rooms or rooms:contains(roomjid)
end

local function roll(sides)
	if sides > 256 then
		return nil, "too many sides"
	end
	local factor = math.floor(256 / sides);
	local cutoff = sides * factor;
	module:log("error", "%d -> %d %d %d", sides, max, factor, cutoff);
	for i=1,10 do
		local randomness = string.byte(rand.bytes(1), 1);
		module:log("error", "%d", randomness);
		if randomness < cutoff then
			return (randomness % sides) + 1
		end
	end
	return nil, "failed to find valid number"
end

local function muc_broadcast_message(event)
	if not is_room_affected(event.room.jid) then
		return
	end

	local stanza = event.stanza;
	local body = stanza:get_child("body");
	if not body then
		return
	end

	local text = body:get_text();
	module:log("error", "%q %q %q", stanza, body, text);
	local dice = s_match(text, "^[%.!]r%s(.+)$");
	if not dice or dice == "" then
		return
	end

	local results = {};
	local count = 0;
	local sum = 0;
	for ndice, sep, sides in s_gmatch(dice, "(%d*)([wd]?)(%d+)") do
		if not sep or sep == "" then
			sides = ndice .. sides
			ndice = "1"
		end
		local ndice = tonumber(ndice);
		count = count + ndice;
		if count > 100 then
			return true
		end
		local sides = tonumber(sides);
		for i=1,ndice do
			local value = roll(sides);
			t_insert(results, tostring(value));
			sum = sum + value;
		end
	end
	body:text("\n⇒ "..t_concat(results, " ").." (sum: "..sum..")");
end

module:hook("muc-broadcast-message", muc_broadcast_message);