1;;; erc-netsplit.el --- Reduce JOIN/QUIT messages on netsplits
2
3;; Copyright (C) 2002, 2003, 2004, 2006, 2007 Free Software Foundation, Inc.
4
5;; Author: Mario Lang <mlang@delysid.org>
6;; Keywords: comm
7
8;; This file is part of GNU Emacs.
9
10;; GNU Emacs is free software; you can redistribute it and/or modify
11;; it under the terms of the GNU General Public License as published by
12;; the Free Software Foundation; either version 2, or (at your option)
13;; any later version.
14
15;; GNU Emacs is distributed in the hope that it will be useful,
16;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18;; GNU General Public License for more details.
19
20;; You should have received a copy of the GNU General Public License
21;; along with GNU Emacs; see the file COPYING.  If not, write to the
22;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
23;; Boston, MA 02110-1301, USA.
24
25;;; Commentary:
26
27;; This module hides quit/join messages if a netsplit occurs.
28;; To enable, add the following to your ~/.emacs:
29;; (require 'erc-netsplit)
30;; (erc-netsplit-mode 1)
31
32;;; Code:
33
34(require 'erc)
35(eval-when-compile (require 'cl))
36
37(defgroup erc-netsplit nil
38  "Netsplit detection tries to automatically figure when a
39netsplit happens, and filters the QUIT messages. It also keeps
40track of netsplits, so that it can filter the JOIN messages on a netjoin too."
41  :group 'erc)
42
43;;;###autoload (autoload 'erc-netsplit-mode "erc-netsplit")
44(define-erc-module netsplit nil
45  "This mode hides quit/join messages if a netsplit occurs."
46  ((erc-netsplit-install-message-catalogs)
47   (add-hook 'erc-server-JOIN-functions 'erc-netsplit-JOIN)
48   (add-hook 'erc-server-MODE-functions 'erc-netsplit-MODE)
49   (add-hook 'erc-server-QUIT-functions 'erc-netsplit-QUIT)
50   (add-hook 'erc-timer-hook 'erc-netsplit-timer))
51  ((remove-hook 'erc-server-JOIN-functions 'erc-netsplit-JOIN)
52   (remove-hook 'erc-server-MODE-functions 'erc-netsplit-MODE)
53   (remove-hook 'erc-server-QUIT-functions 'erc-netsplit-QUIT)
54   (remove-hook 'erc-timer-hook 'erc-netsplit-timer)))
55
56(defcustom erc-netsplit-show-server-mode-changes-flag nil
57  "Set to t to enable display of server mode changes."
58  :group 'erc-netsplit
59  :type 'boolean)
60
61(defcustom erc-netsplit-debug nil
62  "If non-nil, debug messages will be shown in the
63sever buffer."
64  :group 'erc-netsplit
65  :type 'boolean)
66
67(defcustom erc-netsplit-regexp
68  "^[^ @!\"\n]+\\.[^ @!\n]+ [^ @!\n]+\\.[^ @!\"\n]+$"
69  "This regular expression should match quit reasons produced
70by netsplits."
71  :group 'erc-netsplit
72  :type 'regexp)
73
74(defcustom erc-netsplit-hook nil
75  "Run whenever a netsplit is detected the first time.
76Args: PROC is the process the netsplit originated from and
77      SPLIT is the netsplit (e.g. \"server.name.1 server.name.2\")."
78  :group 'erc-hooks
79  :type 'hook)
80
81(defcustom erc-netjoin-hook nil
82  "Run whenever a netjoin is detected the first time.
83Args: PROC is the process the netjoin originated from and
84      SPLIT is the netsplit (e.g. \"server.name.1 server.name.2\")."
85  :group 'erc-hooks
86  :type 'hook)
87
88(defvar erc-netsplit-list nil
89  "This is a list of the form
90\((\"a.b.c.d e.f.g\" TIMESTAMP FIRST-JOIN \"nick1\" ... \"nickn\") ...)
91where FIRST-JOIN is t or nil, depending on whether or not the first
92join from that split has been detected or not.")
93(make-variable-buffer-local 'erc-netsplit-list)
94
95(defun erc-netsplit-install-message-catalogs ()
96  (erc-define-catalog
97   'english
98   '((netsplit	       . "netsplit: %s")
99     (netjoin	       . "netjoin: %s, %N were split")
100     (netjoin-done     . "netjoin: All lost souls are back!")
101     (netsplit-none    . "No netsplits in progress")
102     (netsplit-wholeft . "split: %s missing: %n %t"))))
103
104(defun erc-netsplit-JOIN (proc parsed)
105  "Show/don't show rejoins."
106  (let ((nick (erc-response.sender parsed))
107	(no-next-hook nil))
108    (dolist (elt erc-netsplit-list)
109      (if (member nick (nthcdr 3 elt))
110	  (progn
111	    (if (not (caddr elt))
112		(progn
113		  (erc-display-message
114		   parsed 'notice (process-buffer proc)
115		   'netjoin ?s (car elt) ?N (length (nthcdr 3 elt)))
116		  (setcar (nthcdr 2 elt) t)
117		  (run-hook-with-args 'erc-netjoin-hook proc (car elt))))
118	    ;; need to remove this nick, perhaps the whole entry here.
119	    ;; Note that by removing the nick now, we can't tell if further
120	    ;; join messages (for other channels) should also be
121	    ;; suppressed.
122	    (if (null (nthcdr 4 elt))
123		(progn
124		  (erc-display-message
125		   parsed 'notice (process-buffer proc)
126		   'netjoin-done ?s (car elt))
127		  (setq erc-netsplit-list (delq elt erc-netsplit-list)))
128	      (delete nick elt))
129	    (setq no-next-hook t))))
130    no-next-hook))
131
132(defun erc-netsplit-MODE (proc parsed)
133  "Hide mode changes from servers."
134  ;; regexp matches things with a . in them, and no ! or @ in them.
135  (when (string-match "^[^@!\n]+\\.[^@!\n]+$" (erc-response.sender parsed))
136    (and erc-netsplit-debug
137	 (erc-display-message
138	  parsed 'notice (process-buffer proc)
139	  "[debug] server mode change."))
140    (not erc-netsplit-show-server-mode-changes-flag)))
141
142(defun erc-netsplit-QUIT (proc parsed)
143  "Detect netsplits."
144  (let ((split (erc-response.contents parsed))
145	(nick (erc-response.sender parsed))
146	ass)
147    (when (string-match erc-netsplit-regexp split)
148      (setq ass (assoc split erc-netsplit-list))
149      (if ass
150	  ;; element for this netsplit exists already
151	  (progn
152	    (setcdr (nthcdr 2 ass) (cons nick (nthcdr 3 ass)))
153	    (when (caddr ass)
154	      ;; There was already a netjoin for this netsplit, it
155	      ;; seems like the old one didn't get finished...
156	      (erc-display-message
157	       parsed 'notice (process-buffer proc)
158	       'netsplit ?s split)
159	      (setcar (nthcdr 2 ass) t)
160	      (run-hook-with-args 'erc-netsplit-hook proc split)))
161	;; element for this netsplit does not yet exist
162	(setq erc-netsplit-list
163	      (cons (list split
164			  (erc-current-time)
165			  nil
166			  nick)
167		    erc-netsplit-list))
168	(erc-display-message
169	 parsed 'notice (process-buffer proc)
170	 'netsplit ?s split)
171	(run-hook-with-args 'erc-netsplit-hook proc split))
172      t)))
173
174(defun erc-netsplit-timer (now)
175  "Clean cruft from `erc-netsplit-list' older than 10 minutes."
176  (dolist (elt erc-netsplit-list)
177    (when (> (erc-time-diff (cadr elt) now) 600)
178      (when erc-netsplit-debug
179	(erc-display-message
180	 nil 'notice (current-buffer)
181	 (concat "Netsplit: Removing " (car elt))))
182      (setq erc-netsplit-list (delq elt erc-netsplit-list)))))
183
184;;;###autoload
185(defun erc-cmd-WHOLEFT ()
186  "Show who's gone."
187  (erc-with-server-buffer
188    (if (null erc-netsplit-list)
189	(erc-display-message
190	 nil 'notice 'active
191	 'netsplit-none)
192      (dolist (elt erc-netsplit-list)
193	(erc-display-message
194	 nil 'notice 'active
195	 'netsplit-wholeft ?s (car elt)
196	 ?n (mapconcat 'erc-extract-nick (nthcdr 3 elt) " ")
197	 ?t (if (caddr elt)
198		"(joining)"
199	      "")))))
200  t)
201
202(defalias 'erc-cmd-WL 'erc-cmd-WHOLEFT)
203
204(provide 'erc-netsplit)
205
206;;; erc-netsplit.el ends here
207;;
208;; Local Variables:
209;; indent-tabs-mode: t
210;; tab-width: 8
211;; End:
212
213;; arch-tag: 61a85cb0-7e7b-4312-a4f6-313c7a25a6e8
214