1;;; nnkiboze.el --- select virtual news access for Gnus
2
3;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
4;;   2005, 2006, 2007 Free Software Foundation, Inc.
5
6;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
7;; Keywords: news
8
9;; This file is part of GNU Emacs.
10
11;; GNU Emacs is free software; you can redistribute it and/or modify
12;; it under the terms of the GNU General Public License as published by
13;; the Free Software Foundation; either version 2, or (at your option)
14;; any later version.
15
16;; GNU Emacs is distributed in the hope that it will be useful,
17;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19;; GNU General Public License for more details.
20
21;; You should have received a copy of the GNU General Public License
22;; along with GNU Emacs; see the file COPYING.  If not, write to the
23;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
24;; Boston, MA 02110-1301, USA.
25
26;;; Commentary:
27
28;; The other access methods (nntp, nnspool, etc) are general news
29;; access methods.  This module relies on Gnus and can't be used
30;; separately.
31
32;;; Code:
33
34(require 'nntp)
35(require 'nnheader)
36(require 'gnus)
37(require 'gnus-score)
38(require 'nnoo)
39(require 'mm-util)
40(eval-when-compile (require 'cl))
41
42(nnoo-declare nnkiboze)
43(defvoo nnkiboze-directory (nnheader-concat gnus-directory "kiboze/")
44  "nnkiboze will put its files in this directory.")
45
46(defvoo nnkiboze-level 9
47  "The maximum level to be searched for articles.")
48
49(defvoo nnkiboze-remove-read-articles t
50  "If non-nil, nnkiboze will remove read articles from the kiboze group.")
51
52(defvoo nnkiboze-ephemeral nil
53  "If non-nil, don't store any data anywhere.")
54
55(defvoo nnkiboze-scores nil
56  "Score rules for generating the nnkiboze group.")
57
58(defvoo nnkiboze-regexp nil
59  "Regexp for matching component groups.")
60
61(defvoo nnkiboze-file-coding-system mm-text-coding-system
62  "Coding system for nnkiboze files.")
63
64
65
66(defconst nnkiboze-version "nnkiboze 1.0")
67
68(defvoo nnkiboze-current-group nil)
69(defvoo nnkiboze-status-string "")
70
71(defvoo nnkiboze-headers nil)
72
73
74
75;;; Interface functions.
76
77(nnoo-define-basics nnkiboze)
78
79(deffoo nnkiboze-retrieve-headers (articles &optional group server fetch-old)
80  (nnkiboze-possibly-change-group group)
81  (unless gnus-nov-is-evil
82    (if (stringp (car articles))
83	'headers
84      (let ((nov (nnkiboze-nov-file-name)))
85	(when (file-exists-p nov)
86	  (save-excursion
87	    (set-buffer nntp-server-buffer)
88	    (erase-buffer)
89	    (let ((nnheader-file-coding-system nnkiboze-file-coding-system))
90	      (nnheader-insert-file-contents nov))
91	    (nnheader-nov-delete-outside-range
92	     (car articles) (car (last articles)))
93	    'nov))))))
94
95(deffoo nnkiboze-request-article (article &optional newsgroup server buffer)
96  (nnkiboze-possibly-change-group newsgroup)
97  (if (not (numberp article))
98      ;; This is a real kludge.  It might not work at times, but it
99      ;; does no harm I think.  The only alternative is to offer no
100      ;; article fetching by message-id at all.
101      (nntp-request-article article newsgroup gnus-nntp-server buffer)
102    (let* ((header (gnus-summary-article-header article))
103	   (xref (mail-header-xref header))
104	   num group)
105      (unless xref
106	(error "nnkiboze: No xref"))
107      (unless (string-match " \\([^ ]+\\):\\([0-9]+\\)" xref)
108	(error "nnkiboze: Malformed xref"))
109      (setq num (string-to-number (match-string 2 xref))
110	    group (match-string 1 xref))
111      (or (with-current-buffer buffer
112	    (or (and gnus-use-cache (gnus-cache-request-article num group))
113		(gnus-agent-request-article num group)))
114	  (gnus-request-article num group buffer)))))
115
116(deffoo nnkiboze-request-scan (&optional group server)
117  (nnkiboze-possibly-change-group group)
118  (nnkiboze-generate-group (concat "nnkiboze:" group)))
119
120(deffoo nnkiboze-request-group (group &optional server dont-check)
121  "Make GROUP the current newsgroup."
122  (nnkiboze-possibly-change-group group)
123  (if dont-check
124      t
125    (let ((nov-file (nnkiboze-nov-file-name))
126	  beg end total)
127      (save-excursion
128	(set-buffer nntp-server-buffer)
129	(erase-buffer)
130	(unless (file-exists-p nov-file)
131	  (nnkiboze-request-scan group))
132	(if (not (file-exists-p nov-file))
133	    (nnheader-report 'nnkiboze "Can't select group %s" group)
134	  (let ((nnheader-file-coding-system nnkiboze-file-coding-system))
135	    (nnheader-insert-file-contents nov-file))
136	  (if (zerop (buffer-size))
137	      (nnheader-insert "211 0 0 0 %s\n" group)
138	    (goto-char (point-min))
139	    (when (looking-at "[0-9]+")
140	      (setq beg (read (current-buffer))))
141	    (goto-char (point-max))
142	    (when (re-search-backward "^[0-9]" nil t)
143	      (setq end (read (current-buffer))))
144	    (setq total (count-lines (point-min) (point-max)))
145	    (nnheader-insert "211 %d %d %d %s\n" total beg end group)))))))
146
147(deffoo nnkiboze-close-group (group &optional server)
148  (nnkiboze-possibly-change-group group)
149  ;; Remove NOV lines of articles that are marked as read.
150  (when (and (file-exists-p (nnkiboze-nov-file-name))
151	     nnkiboze-remove-read-articles)
152    (let ((coding-system-for-write nnkiboze-file-coding-system))
153      (with-temp-file (nnkiboze-nov-file-name)
154	(let ((cur (current-buffer))
155	      (nnheader-file-coding-system nnkiboze-file-coding-system))
156	  (nnheader-insert-file-contents (nnkiboze-nov-file-name))
157	  (goto-char (point-min))
158	  (while (not (eobp))
159	    (if (not (gnus-article-read-p (read cur)))
160		(forward-line 1)
161	      (gnus-delete-line))))))
162    (setq nnkiboze-current-group nil)))
163
164(deffoo nnkiboze-open-server (server &optional defs)
165  (unless (assq 'nnkiboze-regexp defs)
166    (push `(nnkiboze-regexp ,server)
167	  defs))
168  (nnoo-change-server 'nnkiboze server defs))
169
170(deffoo nnkiboze-request-delete-group (group &optional force server)
171  (nnkiboze-possibly-change-group group)
172  (when force
173    (let ((files (nconc
174		  (nnkiboze-score-file group)
175		  (list (nnkiboze-nov-file-name)
176			(nnkiboze-nov-file-name ".newsrc")))))
177      (while files
178	(and (file-exists-p (car files))
179	     (file-writable-p (car files))
180	     (delete-file (car files)))
181	(setq files (cdr files)))))
182  (setq nnkiboze-current-group nil)
183  t)
184
185(nnoo-define-skeleton nnkiboze)
186
187
188;;; Internal functions.
189
190(defun nnkiboze-possibly-change-group (group)
191  (setq nnkiboze-current-group group))
192
193(defun nnkiboze-prefixed-name (group)
194  (gnus-group-prefixed-name group '(nnkiboze "")))
195
196;;;###autoload
197(defun nnkiboze-generate-groups ()
198  "\"Usage: emacs -batch -l nnkiboze -f nnkiboze-generate-groups\".
199Finds out what articles are to be part of the nnkiboze groups."
200  (interactive)
201  (let ((nnmail-spool-file nil)
202	(mail-sources nil)
203	(gnus-use-dribble-file nil)
204	(gnus-read-active-file t)
205	(gnus-expert-user t))
206    (gnus))
207  (let* ((gnus-newsrc-alist (gnus-copy-sequence gnus-newsrc-alist))
208	 (newsrc (cdr gnus-newsrc-alist))
209	 gnus-newsrc-hashtb info)
210    (gnus-make-hashtable-from-newsrc-alist)
211    ;; We have copied all the newsrc alist info over to local copies
212    ;; so that we can mess all we want with these lists.
213    (while (setq info (pop newsrc))
214      (when (string-match "nnkiboze" (gnus-info-group info))
215	;; For each kiboze group, we call this function to generate
216	;; it.
217	(nnkiboze-generate-group (gnus-info-group info) t))))
218  (save-excursion
219    (set-buffer gnus-group-buffer)
220    (gnus-group-list-groups)))
221
222(defun nnkiboze-score-file (group)
223  (list (expand-file-name
224	 (concat (file-name-as-directory gnus-kill-files-directory)
225		 (nnheader-translate-file-chars
226		  (concat (nnkiboze-prefixed-name nnkiboze-current-group)
227			  "." gnus-score-file-suffix))))))
228
229(defun nnkiboze-generate-group (group &optional inhibit-list-groups)
230  (let* ((info (nth 2 (gnus-gethash group gnus-newsrc-hashtb)))
231	 (newsrc-file (concat nnkiboze-directory
232			      (nnheader-translate-file-chars
233			       (concat group ".newsrc"))))
234	 (nov-file (concat nnkiboze-directory
235			   (nnheader-translate-file-chars
236			    (concat group ".nov"))))
237	 method nnkiboze-newsrc gname newsrc active
238	 ginfo lowest glevel orig-info nov-buffer
239	 ;; Bind various things to nil to make group entry faster.
240	 (gnus-expert-user t)
241	 (gnus-large-newsgroup nil)
242	 (gnus-score-find-score-files-function 'nnkiboze-score-file)
243	 ;; Use only nnkiboze-score-file!
244	 (gnus-score-use-all-scores nil)
245	 (gnus-use-scoring t)
246	 (gnus-verbose (min gnus-verbose 3))
247	 gnus-select-group-hook gnus-summary-prepare-hook
248	 gnus-thread-sort-functions gnus-show-threads
249	 gnus-visual gnus-suppress-duplicates num-unread)
250    (unless info
251      (error "No such group: %s" group))
252    ;; Load the kiboze newsrc file for this group.
253    (mm-with-unibyte
254      (when (file-exists-p newsrc-file)
255	(load newsrc-file))
256      (let ((coding-system-for-write nnkiboze-file-coding-system))
257	(gnus-make-directory (file-name-directory nov-file))
258	(with-temp-file nov-file
259	  (when (file-exists-p nov-file)
260	    (insert-file-contents nov-file))
261	  (setq nov-buffer (current-buffer))
262	  ;; Go through the active hashtb and add new all groups that match the
263	  ;; kiboze regexp.
264	  (mapatoms
265	   (lambda (group)
266	     (and (string-match nnkiboze-regexp
267				(setq gname (symbol-name group))) ; Match
268		  (not (assoc gname nnkiboze-newsrc)) ; It isn't registered
269		  (numberp (car (symbol-value group))) ; It is active
270		  (or (> nnkiboze-level 7)
271		      (and (setq glevel
272				 (nth 1 (nth 2 (gnus-gethash
273						gname gnus-newsrc-hashtb))))
274			   (>= nnkiboze-level glevel)))
275		  (not (string-match "^nnkiboze:" gname)) ; Exclude kibozes
276		  (push (cons gname (1- (car (symbol-value group))))
277			nnkiboze-newsrc)))
278	   gnus-active-hashtb)
279	  ;; `newsrc' is set to the list of groups that possibly are
280	  ;; component groups to this kiboze group.  This list has elements
281	  ;; on the form `(GROUP . NUMBER)', where NUMBER is the highest
282	  ;; number that has been kibozed in GROUP in this kiboze group.
283	  (setq newsrc nnkiboze-newsrc)
284	  (while newsrc
285	    (if (not (setq active (gnus-gethash
286				   (caar newsrc) gnus-active-hashtb)))
287		;; This group isn't active after all, so we remove it from
288		;; the list of component groups.
289		(setq nnkiboze-newsrc (delq (car newsrc) nnkiboze-newsrc))
290	      (setq lowest (cdar newsrc))
291	      ;; Ok, we have a valid component group, so we jump to it.
292	      (switch-to-buffer gnus-group-buffer)
293	      (gnus-group-jump-to-group (caar newsrc))
294	      (gnus-message 3 "nnkiboze: Checking %s..." (caar newsrc))
295	      (setq ginfo (gnus-get-info (gnus-group-group-name))
296		    orig-info (gnus-copy-sequence ginfo)
297		    num-unread (car (gnus-gethash (caar newsrc)
298						  gnus-newsrc-hashtb)))
299	      (unwind-protect
300		  (progn
301		    ;; We set all list of article marks to nil.  Since we operate
302		    ;; on copies of the real lists, we can destroy anything we
303		    ;; want here.
304		    (when (nth 3 ginfo)
305		      (setcar (nthcdr 3 ginfo) nil))
306		    ;; We set the list of read articles to be what we expect for
307		    ;; this kiboze group -- either nil or `(1 . LOWEST)'.
308		    (when ginfo
309		      (setcar (nthcdr 2 ginfo)
310			      (and (not (= lowest 1)) (cons 1 lowest))))
311		    (when (and (or (not ginfo)
312				   (> (length (gnus-list-of-unread-articles
313					       (car ginfo)))
314				      0))
315			       (progn
316				 (ignore-errors
317				   (gnus-group-select-group nil))
318				 (eq major-mode 'gnus-summary-mode)))
319		      ;; We are now in the group where we want to be.
320		      (setq method (gnus-find-method-for-group
321				    gnus-newsgroup-name))
322		      (when (eq method gnus-select-method)
323			(setq method nil))
324		      ;; We go through the list of scored articles.
325		      (while gnus-newsgroup-scored
326			(when (> (caar gnus-newsgroup-scored) lowest)
327			  ;; If it has a good score, then we enter this article
328			  ;; into the kiboze group.
329			  (nnkiboze-enter-nov
330			   nov-buffer
331			   (gnus-summary-article-header
332			    (caar gnus-newsgroup-scored))
333			   gnus-newsgroup-name))
334			(setq gnus-newsgroup-scored (cdr gnus-newsgroup-scored)))
335		      ;; That's it.  We exit this group.
336		      (when (eq major-mode 'gnus-summary-mode)
337			(kill-buffer (current-buffer)))))
338		;; Restore the proper info.
339		(when ginfo
340		  (setcdr ginfo (cdr orig-info)))
341		(setcar (gnus-gethash (caar newsrc) gnus-newsrc-hashtb)
342			num-unread)))
343	    (setcdr (car newsrc) (cdr active))
344	    (gnus-message 3 "nnkiboze: Checking %s...done" (caar newsrc))
345	    (setq newsrc (cdr newsrc)))))
346      ;; We save the kiboze newsrc for this group.
347      (gnus-make-directory (file-name-directory newsrc-file))
348      (with-temp-file newsrc-file
349	(insert "(setq nnkiboze-newsrc '")
350	(gnus-prin1 nnkiboze-newsrc)
351	(insert ")\n")))
352  (unless inhibit-list-groups
353    (save-excursion
354      (set-buffer gnus-group-buffer)
355      (gnus-group-list-groups)))
356  t))
357
358(defun nnkiboze-enter-nov (buffer header group)
359  (save-excursion
360    (set-buffer buffer)
361    (goto-char (point-max))
362    (let ((prefix (gnus-group-real-prefix group))
363	  (oheader (copy-sequence header))
364	  article)
365      (if (zerop (forward-line -1))
366	  (progn
367	    (setq article (1+ (read (current-buffer))))
368	    (forward-line 1))
369	(setq article 1))
370      (mail-header-set-number oheader article)
371      (with-temp-buffer
372	(insert (or (mail-header-xref oheader) ""))
373	(goto-char (point-min))
374	(if (re-search-forward " [^ ]+:[0-9]+" nil t)
375	    (goto-char (match-beginning 0))
376	  (or (eobp) (forward-char 1)))
377	;; The first Xref has to be the group this article
378	;; really came for - this is the article nnkiboze
379	;; will request when it is asked for the article.
380	(insert " " group ":"
381		(int-to-string (mail-header-number header)) " ")
382	(while (re-search-forward " [^ ]+:[0-9]+" nil t)
383	  (goto-char (1+ (match-beginning 0)))
384	  (insert prefix))
385	(mail-header-set-xref oheader (buffer-string)))
386      (nnheader-insert-nov oheader))))
387
388(defun nnkiboze-nov-file-name (&optional suffix)
389  (concat (file-name-as-directory nnkiboze-directory)
390	  (nnheader-translate-file-chars
391	   (concat (nnkiboze-prefixed-name nnkiboze-current-group)
392		   (or suffix ".nov")))))
393
394(provide 'nnkiboze)
395
396;;; arch-tag: 66068271-bdc9-4801-bcde-779702e73a05
397;;; nnkiboze.el ends here
398