module:depends("muc"); local jid_resource = require "util.jid".resource; local st = require "util.stanza"; local prefixes = module:get_option("muc_inject_mentions_prefixes", nil) local suffixes = module:get_option("muc_inject_mentions_suffixes", nil) local enabled_rooms = module:get_option("muc_inject_mentions_enabled_rooms", nil) local disabled_rooms = module:get_option("muc_inject_mentions_disabled_rooms", nil) local mention_delimiters = module:get_option_set("muc_inject_mentions_mention_delimiters", {" ", "", "\n"}) local append_mentions = module:get_option("muc_inject_mentions_append_mentions", false) local strip_out_prefixes = module:get_option("muc_inject_mentions_strip_out_prefixes", false) local reserved_nicks = module:get_option("muc_inject_mentions_reserved_nicks", false) local reference_xmlns = "urn:xmpp:reference:0" local function get_participants(room) if not reserved_nicks then local occupants = room._occupants local key, occupant = next(occupants) return function () while occupant do -- luacheck: ignore local nick = jid_resource(occupant.nick); local bare_jid = occupant.bare_jid key, occupant = next(occupants, key) return bare_jid, nick end end else local generator = room:each_affiliation() local jid, _, affiliation_data = generator(nil, nil) return function () while jid do local bare_jid, nick = jid, (affiliation_data or {})["reserved_nickname"] jid, _, affiliation_data = generator(nil, bare_jid) if nick then return bare_jid, nick end end end end end local function add_mention(mentions, bare_jid, first, last, prefix_indices, has_prefix) if strip_out_prefixes then if has_prefix then table.insert(prefix_indices, first-1) end first = first - #prefix_indices last = last - #prefix_indices end mentions[first] = {bare_jid=bare_jid, first=first, last=last} end local function get_client_mentions(stanza) local has_mentions = false local client_mentions = {} for element in stanza:childtags("reference", reference_xmlns) do if element.attr.type == "mention" then local key = tonumber(element.attr.begin) + 1 -- count starts at 0 client_mentions[key] = {bare_jid=element.attr.uri, first=element.attr.begin, last=element.attr["end"]} has_mentions = true end end return has_mentions, client_mentions end local function is_room_eligible(jid) if not enabled_rooms and not disabled_rooms then return true; end if enabled_rooms and not disabled_rooms then for _, _jid in ipairs(enabled_rooms) do if _jid == jid then return true end end return false end if disabled_rooms and not enabled_rooms then for _, _jid in ipairs(disabled_rooms) do if _jid == jid then return false end end return true end return true end local function has_nick_prefix(body, first) -- There are no configured prefixes if not prefixes or #prefixes < 1 then return false end -- Prefix must have a space before it, -- be the first character of the body -- or be the first character after a new line if not mention_delimiters:contains(body:sub(first - 2, first - 2)) then return false end local prefix = body:sub(first - 1, first - 1) for _, _prefix in ipairs(prefixes) do if prefix == _prefix then return true end end return false end local function has_nick_suffix(body, last) -- There are no configured suffixes if not suffixes or #suffixes < 1 then return false end -- Suffix must have a space after it, -- be the last character of the body -- or be the last character before a new line if not mention_delimiters:contains(body:sub(last + 2, last + 2)) then return false end local suffix = body:sub(last+1, last+1) for _, _suffix in ipairs(suffixes) do if suffix == _suffix then return true end end return false end local function search_mentions(room, body, client_mentions) local mentions, prefix_indices = {}, {} for bare_jid, nick in get_participants(room) do -- Check for multiple mentions to the same nickname in a message -- Hey @nick remember to... Ah, also @nick please let me know if... local matches = {} local _first local _last = 0 while true do -- Use plain search as nick could contain -- characters used in Lua patterns _first, _last = body:find(nick, _last + 1, true) if _first == nil then break end table.insert(matches, {first=_first, last=_last}) end -- Filter out intentional mentions from unintentional ones for _, match in ipairs(matches) do local first, last = match.first, match.last -- Only append new mentions in case the client already sent some if not client_mentions[first] then -- Body only contains nickname or is between spaces, new lines or at the end/start of the body if mention_delimiters:contains(body:sub(first - 1, first - 1)) and mention_delimiters:contains(body:sub(last + 1, last + 1)) then add_mention(mentions, bare_jid, first, last, prefix_indices, false) else -- Check if occupant is mentioned using affixes local has_prefix = has_nick_prefix(body, first) local has_suffix = has_nick_suffix(body, last) -- @nickname: ... if has_prefix and has_suffix then add_mention(mentions, bare_jid, first, last, prefix_indices, has_prefix) -- @nickname ... elseif has_prefix and not has_suffix then if mention_delimiters:contains(body:sub(last + 1, last + 1)) then add_mention(mentions, bare_jid, first, last, prefix_indices, has_prefix) end -- nickname: ... elseif not has_prefix and has_suffix then if mention_delimiters:contains(body:sub(first - 1, first - 1)) then add_mention(mentions, bare_jid, first, last, prefix_indices, has_prefix) end end end end end end return mentions, prefix_indices end local function muc_inject_mentions(event) local room, stanza = event.room, event.stanza; local body = stanza:get_child("body") if not body then return; end -- Inject mentions only if the room is configured for them if not is_room_eligible(room.jid) then return; end -- Only act on messages that do not include mentions -- unless configuration states otherwise. local has_mentions, client_mentions = get_client_mentions(stanza) if has_mentions and not append_mentions then return; end local body_text = body:get_text() local mentions, prefix_indices = search_mentions(room, body_text, client_mentions) for _, mention in pairs(mentions) do -- https://xmpp.org/extensions/xep-0372.html#usecase_mention stanza:tag( "reference", { xmlns=reference_xmlns, begin=tostring(mention.first - 1), -- count starts at 0 ["end"]=tostring(mention.last - 1), type="mention", uri="xmpp:" .. mention.bare_jid, } ):up() end if strip_out_prefixes then local body_without_prefixes = "" local from = 0 if #prefix_indices > 0 then for _, prefix_index in ipairs(prefix_indices) do body_without_prefixes = body_without_prefixes .. body_text:sub(from, prefix_index-1) from = prefix_index + 1 end body_without_prefixes = body_without_prefixes .. body_text:sub(from, #body_text) -- Replace original body containing prefixes stanza:maptags( function(tag) if tag.name ~= "body" then return tag end return st.stanza("body"):text(body_without_prefixes) end ) end end end module:hook("muc-occupant-groupchat", muc_inject_mentions)