aboutsummaryrefslogtreecommitdiffstats
path: root/plugins/muc/history.lib.lua
blob: 0fc0dfa3dfd5332716461a7e974c50fb060f1b46 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
-- Copyright (C) 2014 Daurnimator
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

local gettime = os.time;
local datetime = require "util.datetime";
local st = require "util.stanza";

local default_history_length = 20;
local max_history_length = module:get_option_number("max_history_messages", math.huge);

local function set_max_history_length(_max_history_length)
	max_history_length = _max_history_length or math.huge;
end

local function get_historylength(room)
	return math.min(room._data.history_length or default_history_length, max_history_length);
end

local function set_historylength(room, length)
	if length then
		length = assert(tonumber(length), "Length not a valid number");
	end
	if length == default_history_length then length = nil; end
	room._data.history_length = length;
	return true;
end

module:hook("muc-config-form", function(event)
	table.insert(event.form, {
		name = "muc#roomconfig_historylength";
		type = "text-single";
		label = "Maximum Number of History Messages Returned by Room";
		value = tostring(get_historylength(event.room));
	});
end);

module:hook("muc-config-submitted/muc#roomconfig_historylength", function(event)
	if set_historylength(event.room, event.value) then
		event.status_codes["104"] = true;
	end
end);

local function parse_history(stanza)
	local x_tag = stanza:get_child("x", "http://jabber.org/protocol/muc");
	local history_tag = x_tag and x_tag:get_child("history", "http://jabber.org/protocol/muc");
	if not history_tag then
		return nil, default_history_length, nil;
	end

	local maxchars = tonumber(history_tag.attr.maxchars);

	local maxstanzas = tonumber(history_tag.attr.maxstanzas);

	-- messages received since the UTC datetime specified
	local since = history_tag.attr.since;
	if since then
		since = datetime.parse(since);
	end

	-- messages received in the last "X" seconds.
	local seconds = tonumber(history_tag.attr.seconds);
	if seconds then
		seconds = gettime() - seconds;
		if since then
			since = math.max(since, seconds);
		else
			since = seconds;
		end
	end

	return maxchars, maxstanzas, since;
end

module:hook("muc-get-history", function(event)
	local room = event.room;
	local history = room._history; -- send discussion history
	if not history then return nil end
	local history_len = #history;

	local to = event.to;
	local maxchars = event.maxchars;
	local maxstanzas = event.maxstanzas or history_len;
	local since = event.since;
	local n = 0;
	local charcount = 0;
	for i=history_len,1,-1 do
		local entry = history[i];
		if maxchars then
			if not entry.chars then
				entry.stanza.attr.to = "";
				entry.chars = #tostring(entry.stanza);
			end
			charcount = charcount + entry.chars + #to;
			if charcount > maxchars then break; end
		end
		if since and since > entry.timestamp then break; end
		if n + 1 > maxstanzas then break; end
		n = n + 1;
	end

	local i = history_len-n+1
	function event.next_stanza()
		if i > history_len then return nil end
		local entry = history[i];
		local msg = entry.stanza;
		msg.attr.to = to;
		i = i + 1;
		return msg;
	end
	return true;
end);

local function send_history(room, stanza)
	local maxchars, maxstanzas, since = parse_history(stanza);
	local event = {
		room = room;
		to = stanza.attr.from; -- `to` is required to calculate the character count for `maxchars`
		maxchars = maxchars, maxstanzas = maxstanzas, since = since;
		next_stanza = function() end; -- events should define this iterator
	};
	module:fire_event("muc-get-history", event);
	for msg in event.next_stanza, event do
		room:route_stanza(msg);
	end
end

-- Send history on join
module:hook("muc-occupant-session-new", function(event)
	send_history(event.room, event.stanza);
end, 50); -- Before subject(20)

-- add to history
module:hook("muc-add-history", function(event)
	local historic = event.stanza:get_child("body");
	if historic then
		local room = event.room
		local history = room._history;
		if not history then history = {}; room._history = history; end
		local stanza = st.clone(event.stanza);
		stanza.attr.to = "";
		local ts = gettime();
		local stamp = datetime.datetime(ts);
		stanza:tag("delay", {xmlns = "urn:xmpp:delay", from = module.host, stamp = stamp}):up(); -- XEP-0203
		stanza:tag("x", {xmlns = "jabber:x:delay", from = module.host, stamp = datetime.legacy()}):up(); -- XEP-0091 (deprecated)
		local entry = { stanza = stanza, timestamp = ts };
		table.insert(history, entry);
		while #history > get_historylength(room) do table.remove(history, 1) end
	end
	return true;
end, -1);

-- Have a single muc-add-history event, so that plugins can mark it
-- as handled without stopping other muc-broadcast-message handlers
module:hook("muc-broadcast-message", function(event)
	module:fire_event("muc-add-history", event);
end);

return {
	set_max_length = set_max_history_length;
	parse_history = parse_history;
	send = send_history;
	get_length = get_historylength;
	set_length = set_historylength;
};