lisp/gnus-topic.el

   1 ;;; gnus-topic.el --- a folding minor mode for Gnus group buffers
   2 ;; Copyright (C) 1995,96 Free Software Foundation, Inc.
   3
   4 ;; Author: Ilja Weis <kult@uni-paderborn.de>
   5 ;;      Lars Magne Ingebrigtsen <larsi@ifi.uio.no>
   6 ;; Keywords: news
   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., 59 Temple Place - Suite 330,
  23 ;; Boston, MA 02111-1307, USA.
  24
  25 ;;; Commentary:
  26
  27 ;;; Code:
  28
  29 (require 'gnus)
  30 (eval-when-compile (require 'cl))
  31
  32 (defvar gnus-topic-mode nil
  33   "Minor mode for Gnus group buffers.")
  34
  35 (defvar gnus-topic-mode-hook nil
  36   "Hook run in topic mode buffers.")
  37
  38 (defvar gnus-topic-line-format "%i[ %(%{%n%}%) -- %A ]%v\n"
  39   "Format of topic lines.
  40 It works along the same lines as a normal formatting string,
  41 with some simple extensions.
  42
  43 %i  Indentation based on topic level.
  44 %n  Topic name.
  45 %v  Nothing if the topic is visible, \"...\" otherwise.
  46 %g  Number of groups in the topic.
  47 %a  Number of unread articles in the groups in the topic.
  48 %A  Number of unread articles in the groups in the topic and its subtopics.
  49 ")
  50
  51 (defvar gnus-topic-indent-level 2
  52   "*How much each subtopic should be indented.")
  53
  54 ;; Internal variables.
  55
  56 (defvar gnus-topic-active-topology nil)
  57 (defvar gnus-topic-active-alist nil)
  58
  59 (defvar gnus-topology-checked-p nil
  60   "Whether the topology has been checked in this session.")
  61
  62 (defvar gnus-topic-killed-topics nil)
  63 (defvar gnus-topic-inhibit-change-level nil)
  64 (defvar gnus-topic-tallied-groups nil)
  65
  66 (defconst gnus-topic-line-format-alist
  67   `((?n name ?s)
  68     (?v visible ?s)
  69     (?i indentation ?s)
  70     (?g number-of-groups ?d)
  71     (?a (gnus-topic-articles-in-topic entries) ?d)
  72     (?A total-number-of-articles ?d)
  73     (?l level ?d)))
  74
  75 (defvar gnus-topic-line-format-spec nil)
  76
  77 ;; Functions.
  78
  79 (defun gnus-group-topic-name ()
  80   "The name of the topic on the current line."
  81   (let ((topic (get-text-property (gnus-point-at-bol) 'gnus-topic)))
  82     (and topic (symbol-name topic))))
  83
  84 (defun gnus-group-topic-level ()
  85   "The level of the topic on the current line."
  86   (get-text-property (gnus-point-at-bol) 'gnus-topic-level))
  87
  88 (defun gnus-group-topic-unread ()
  89   "The number of unread articles in topic on the current line."
  90   (get-text-property (gnus-point-at-bol) 'gnus-topic-unread))
  91
  92 (defun gnus-topic-unread (topic)
  93   "Return the number of unread articles in TOPIC."
  94   (or (save-excursion
  95         (and (gnus-topic-goto-topic topic)
  96              (gnus-group-topic-unread)))
  97       0))
  98
  99 (defun gnus-topic-init-alist ()
 100   "Initialize the topic structures."
 101   (setq gnus-topic-topology
 102         (cons (list "Gnus" 'visible)
 103               (mapcar (lambda (topic)
 104                         (list (list (car topic) 'visible)))
 105                       '(("misc")))))
 106   (setq gnus-topic-alist
 107         (list (cons "misc"
 108                     (mapcar (lambda (info) (gnus-info-group info))
 109                             (cdr gnus-newsrc-alist)))
 110               (list "Gnus")))
 111   (gnus-topic-enter-dribble))
 112
 113 (defun gnus-group-prepare-topics (level &optional all lowest regexp list-topic topic-level)
 114   "List all newsgroups with unread articles of level LEVEL or lower, and
 115 use the `gnus-group-topics' to sort the groups.
 116 If ALL is non-nil, list groups that have no unread articles.
 117 If LOWEST is non-nil, list all newsgroups of level LOWEST or higher."
 118   (set-buffer gnus-group-buffer)
 119   (let ((buffer-read-only nil)
 120         (lowest (or lowest 1)))
 121
 122     (setq gnus-topic-tallied-groups nil)
 123
 124     (when (or (not gnus-topic-alist)
 125               (not gnus-topology-checked-p))
 126       (gnus-topic-check-topology))
 127
 128     (unless list-topic
 129       (erase-buffer))
 130
 131     ;; List dead groups?
 132     (when (and (>= level gnus-level-zombie) (<= lowest gnus-level-zombie))
 133       (gnus-group-prepare-flat-list-dead
 134        (setq gnus-zombie-list (sort gnus-zombie-list 'string<))
 135        gnus-level-zombie ?Z
 136        regexp))
 137
 138     (when (and (>= level gnus-level-killed) (<= lowest gnus-level-killed))
 139       (gnus-group-prepare-flat-list-dead
 140        (setq gnus-killed-list (sort gnus-killed-list 'string<))
 141        gnus-level-killed ?K
 142        regexp))
 143
 144     ;; Use topics.
 145     (when (< lowest gnus-level-zombie)
 146       (if list-topic
 147           (let ((top (gnus-topic-find-topology list-topic)))
 148             (gnus-topic-prepare-topic (cdr top) (car top)
 149                                       (or topic-level level) all))
 150         (gnus-topic-prepare-topic gnus-topic-topology 0
 151                                   (or topic-level level) all))))
 152
 153   (gnus-group-set-mode-line)
 154   (setq gnus-group-list-mode (cons level all))
 155   (run-hooks 'gnus-group-prepare-hook))
 156
 157 (defun gnus-topic-prepare-topic (topicl level &optional list-level all silent)
 158   "Insert TOPIC into the group buffer.
 159 If SILENT, don't insert anything.  Return the number of unread
 160 articles in the topic and its subtopics."
 161   (let* ((type (pop topicl))
 162          (entries (gnus-topic-find-groups (car type) list-level all))
 163          (visiblep (and (eq (nth 1 type) 'visible) (not silent)))
 164          (gnus-group-indentation
 165           (make-string (* gnus-topic-indent-level level) ? ))
 166          (beg (progn (beginning-of-line) (point)))
 167          (topicl (reverse topicl))
 168          (all-entries entries)
 169          (unread 0)
 170          (topic (car type))
 171          info entry end active)
 172     ;; Insert any sub-topics.
 173     (while topicl
 174       (incf unread
 175             (gnus-topic-prepare-topic
 176              (pop topicl) (1+ level) list-level all
 177              (not visiblep))))
 178     (setq end (point))
 179     (goto-char beg)
 180     ;; Insert all the groups that belong in this topic.
 181     (while (setq entry (pop entries))
 182       (when visiblep
 183         (if (stringp entry)
 184             ;; Dead groups.
 185             (gnus-group-insert-group-line
 186              entry (if (member entry gnus-zombie-list) 8 9)
 187              nil (- (1+ (cdr (setq active (gnus-active entry))))
 188                     (car active)) nil)
 189           ;; Living groups.
 190           (when (setq info (nth 2 entry))
 191             (gnus-group-insert-group-line
 192              (gnus-info-group info)
 193              (gnus-info-level info) (gnus-info-marks info)
 194              (car entry) (gnus-info-method info)))))
 195       (when (and (listp entry)
 196                  (numberp (car entry))
 197                  (not (member (gnus-info-group (setq info (nth 2 entry)))
 198                               gnus-topic-tallied-groups)))
 199         (push (gnus-info-group info) gnus-topic-tallied-groups)
 200         (incf unread (car entry))))
 201     (goto-char beg)
 202     ;; Insert the topic line.
 203     (unless silent
 204       (gnus-extent-start-open (point))
 205       (gnus-topic-insert-topic-line
 206        (car type) visiblep
 207        (not (eq (nth 2 type) 'hidden))
 208        level all-entries unread))
 209     (goto-char end)
 210     unread))
 211
 212 (defun gnus-topic-find-groups (topic &optional level all)
 213   "Return entries for all visible groups in TOPIC."
 214   (let ((groups (cdr (assoc topic gnus-topic-alist)))
 215         info clevel unread group lowest params visible-groups entry active)
 216     (setq lowest (or lowest 1))
 217     (setq level (or level 7))
 218     ;; We go through the newsrc to look for matches.
 219     (while groups
 220       (setq entry (gnus-gethash (setq group (pop groups)) gnus-newsrc-hashtb)
 221             info (nth 2 entry)
 222             params (gnus-info-params info)
 223             active (gnus-active group)
 224             unread (or (car entry)
 225                        (and (not (equal group "dummy.group"))
 226                             active
 227                             (- (1+ (cdr active)) (car active))))
 228             clevel (or (gnus-info-level info)
 229                        (if (member group gnus-zombie-list) 8 9)))
 230       (and
 231        unread                           ; nil means that the group is dead.
 232        (<= clevel level)
 233        (>= clevel lowest)               ; Is inside the level we want.
 234        (or all
 235            (if (eq unread t)
 236                gnus-group-list-inactive-groups
 237              (> unread 0))
 238            (and gnus-list-groups-with-ticked-articles
 239                 (cdr (assq 'tick (gnus-info-marks info))))
 240                                         ; Has right readedness.
 241            ;; Check for permanent visibility.
 242            (and gnus-permanently-visible-groups
 243                 (string-match gnus-permanently-visible-groups group))
 244            (memq 'visible params)
 245            (cdr (assq 'visible params)))
 246        ;; Add this group to the list of visible groups.
 247        (push (or entry group) visible-groups)))
 248     (nreverse visible-groups)))
 249
 250 (defun gnus-topic-remove-topic (&optional insert total-remove hide in-level)
 251   "Remove the current topic."
 252   (let ((topic (gnus-group-topic-name))
 253         (level (gnus-group-topic-level))
 254         (beg (progn (beginning-of-line) (point)))
 255         buffer-read-only)
 256     (when topic
 257       (while (and (zerop (forward-line 1))
 258                   (> (or (gnus-group-topic-level) (1+ level)) level)))
 259       (delete-region beg (point))
 260       (setcar (cdadr (gnus-topic-find-topology topic))
 261               (if insert 'visible 'invisible))
 262       (when hide
 263         (setcdr (cdadr (gnus-topic-find-topology topic))
 264                 (list hide)))
 265       (unless total-remove
 266         (gnus-topic-insert-topic topic in-level)))))
 267
 268 (defun gnus-topic-insert-topic (topic &optional level)
 269   "Insert TOPIC."
 270   (gnus-group-prepare-topics
 271    (car gnus-group-list-mode) (cdr gnus-group-list-mode)
 272    nil nil topic level))
 273
 274 (defun gnus-topic-fold (&optional insert)
 275   "Remove/insert the current topic."
 276   (let ((topic (gnus-group-topic-name)))
 277     (when topic
 278       (save-excursion
 279         (if (not (gnus-group-active-topic-p))
 280             (gnus-topic-remove-topic
 281              (or insert (not (gnus-topic-visible-p))))
 282           (let ((gnus-topic-topology gnus-topic-active-topology)
 283                 (gnus-topic-alist gnus-topic-active-alist)
 284                 (gnus-group-list-mode (cons 5 t)))
 285             (gnus-topic-remove-topic
 286              (or insert (not (gnus-topic-visible-p))) nil nil 9)))))))
 287
 288 (defun gnus-group-topic-p ()
 289   "Return non-nil if the current line is a topic."
 290   (gnus-group-topic-name))
 291
 292 (defun gnus-topic-visible-p ()
 293   "Return non-nil if the current topic is visible."
 294   (get-text-property (gnus-point-at-bol) 'gnus-topic-visible))
 295
 296 (defun gnus-topic-insert-topic-line (name visiblep shownp level entries
 297                                           &optional unread)
 298   (let* ((visible (if visiblep "" "..."))
 299          (indentation (make-string (* gnus-topic-indent-level level) ? ))
 300          (total-number-of-articles unread)
 301          (number-of-groups (length entries))
 302          (active-topic (eq gnus-topic-alist gnus-topic-active-alist)))
 303     (beginning-of-line)
 304     ;; Insert the text.
 305     (gnus-add-text-properties
 306      (point)
 307      (prog1 (1+ (point))
 308        (eval gnus-topic-line-format-spec)
 309        (gnus-topic-remove-excess-properties)1)
 310      (list 'gnus-topic (intern name)
 311            'gnus-topic-level level
 312            'gnus-topic-unread unread
 313            'gnus-active active-topic
 314            'gnus-topic-visible visiblep))))
 315
 316 (defun gnus-topic-previous-topic (topic)
 317   "Return the previous topic on the same level as TOPIC."
 318   (let ((top (cddr (gnus-topic-find-topology
 319                     (gnus-topic-parent-topic topic)))))
 320     (unless (equal topic (caaar top))
 321       (while (and top (not (equal (caaadr top) topic)))
 322         (setq top (cdr top)))
 323       (caaar top))))
 324
 325 (defun gnus-topic-parent-topic (topic &optional topology)
 326   "Return the parent of TOPIC."
 327   (unless topology
 328     (setq topology gnus-topic-topology))
 329   (let ((parent (car (pop topology)))
 330         result found)
 331     (while (and topology
 332                 (not (setq found (equal (caaar topology) topic)))
 333                 (not (setq result (gnus-topic-parent-topic topic
 334                                                            (car topology)))))
 335       (setq topology (cdr topology)))
 336     (or result (and found parent))))
 337
 338 (defun gnus-topic-next-topic (topic &optional previous)
 339   "Return the next sibling of TOPIC."
 340   (let ((topology gnus-topic-topology)
 341         (parentt (cddr (gnus-topic-find-topology
 342                         (gnus-topic-parent-topic topic))))
 343         prev)
 344     (while (and parentt
 345                 (not (equal (caaar parentt) topic)))
 346       (setq prev (caaar parentt)
 347             parentt (cdr parentt)))
 348     (if previous
 349         prev
 350       (caaadr parentt))))
 351
 352 (defun gnus-topic-find-topology (topic &optional topology level remove)
 353   "Return the topology of TOPIC."
 354   (unless topology
 355     (setq topology gnus-topic-topology)
 356     (setq level 0))
 357   (let ((top topology)
 358         result)
 359     (if (equal (caar topology) topic)
 360         (progn
 361           (when remove
 362             (delq topology remove))
 363           (cons level topology))
 364       (setq topology (cdr topology))
 365       (while (and topology
 366                   (not (setq result (gnus-topic-find-topology
 367                                      topic (car topology) (1+ level)
 368                                      (and remove top)))))
 369         (setq topology (cdr topology)))
 370       result)))
 371
 372 (gnus-add-shutdown 'gnus-topic-close 'gnus)
 373
 374 (defun gnus-topic-close ()
 375   (setq gnus-topic-active-topology nil
 376         gnus-topic-active-alist nil
 377         gnus-topic-killed-topics nil
 378         gnus-topic-tallied-groups nil
 379         gnus-topology-checked-p nil))
 380
 381 (defun gnus-topic-check-topology ()
 382   ;; The first time we set the topology to whatever we have
 383   ;; gotten here, which can be rather random.
 384   (unless gnus-topic-alist
 385     (gnus-topic-init-alist))
 386
 387   (setq gnus-topology-checked-p t)
 388   (let ((topics (gnus-topic-list))
 389         (alist gnus-topic-alist)
 390         changed)
 391     (while alist
 392       (unless (member (caar alist) topics)
 393         (nconc gnus-topic-topology
 394                (list (list (list (caar alist) 'visible))))
 395         (setq changed t))
 396       (setq alist (cdr alist)))
 397     (when changed
 398       (gnus-topic-enter-dribble)))
 399   (let* ((tgroups (apply 'append (mapcar (lambda (entry) (cdr entry))
 400                                          gnus-topic-alist)))
 401          (entry (assoc (caar gnus-topic-topology) gnus-topic-alist))
 402          (newsrc gnus-newsrc-alist)
 403          group)
 404     (while newsrc
 405       (unless (member (setq group (gnus-info-group (pop newsrc))) tgroups)
 406         (setcdr entry (cons group (cdr entry)))))))
 407
 408 (defvar gnus-tmp-topics nil)
 409 (defun gnus-topic-list (&optional topology)
 410   (unless topology
 411     (setq topology gnus-topic-topology
 412           gnus-tmp-topics nil))
 413   (push (caar topology) gnus-tmp-topics)
 414   (mapcar 'gnus-topic-list (cdr topology))
 415   gnus-tmp-topics)
 416
 417 (defun gnus-topic-enter-dribble ()
 418   (gnus-dribble-enter
 419    (format "(setq gnus-topic-topology '%S)" gnus-topic-topology)))
 420
 421 (defun gnus-topic-articles-in-topic (entries)
 422   (let ((total 0)
 423         number)
 424     (while entries
 425       (when (numberp (setq number (car (pop entries))))
 426         (incf total number)))
 427     total))
 428
 429 (defun gnus-group-topic (group)
 430   "Return the topic GROUP is a member of."
 431   (let ((alist gnus-topic-alist)
 432         out)
 433     (while alist
 434       (when (member group (cdar alist))
 435         (setq out (caar alist)
 436               alist nil))
 437       (setq alist (cdr alist)))
 438     out))
 439
 440 (defun gnus-topic-goto-topic (topic)
 441   "Go to TOPIC."
 442   (when topic
 443     (gnus-goto-char (text-property-any (point-min) (point-max)
 444                                        'gnus-topic (intern topic)))))
 445
 446 (defun gnus-group-parent-topic ()
 447   "Return the name of the current topic."
 448   (let ((result
 449          (or (get-text-property (point) 'gnus-topic)
 450              (save-excursion
 451                (and (gnus-goto-char (previous-single-property-change
 452                                      (point) 'gnus-topic))
 453                     (get-text-property (max (1- (point)) (point-min))
 454                                        'gnus-topic))))))
 455     (when result
 456       (symbol-name result))))
 457
 458 (defun gnus-topic-update-topic ()
 459   "Update all parent topics to the current group."
 460   (when (and (eq major-mode 'gnus-group-mode)
 461              gnus-topic-mode)
 462     (let ((group (gnus-group-group-name))
 463           (buffer-read-only nil))
 464       (when (and group (gnus-get-info group)
 465                  (gnus-topic-goto-topic (gnus-group-parent-topic)))
 466         (gnus-topic-update-topic-line (gnus-group-topic-name))
 467         (gnus-group-goto-group group)
 468         (gnus-group-position-point)))))
 469
 470 (defun gnus-topic-goto-missing-group (group)
 471   "Place point where GROUP is supposed to be inserted."
 472   (let* ((topic (gnus-group-topic group))
 473          (groups (cdr (assoc topic gnus-topic-alist)))
 474          (g (cdr (member group groups)))
 475          (unfound t))
 476     (while (and g unfound)
 477       (when (gnus-group-goto-group (pop g))
 478         (beginning-of-line)
 479         (setq unfound nil)))
 480     (when unfound
 481       (setq g (cdr (member group (reverse groups))))
 482       (while (and g unfound)
 483         (when (gnus-group-goto-group (pop g))
 484           (forward-line 1)
 485           (setq unfound nil)))
 486       (when unfound
 487         (gnus-topic-goto-topic topic)
 488         (forward-line 1)))))
 489
 490 (defun gnus-topic-update-topic-line (topic-name &optional reads)
 491   (let* ((top (gnus-topic-find-topology topic-name))
 492          (type (cadr top))
 493          (children (cddr top))
 494          (entries (gnus-topic-find-groups
 495                    (car type) (car gnus-group-list-mode)
 496                    (cdr gnus-group-list-mode)))
 497          (parent (gnus-topic-parent-topic topic-name))
 498          (all-entries entries)
 499          (unread 0)
 500          old-unread entry)
 501     (when (gnus-topic-goto-topic (car type))
 502       ;; Tally all the groups that belong in this topic.
 503       (if reads
 504           (setq unread (- (gnus-group-topic-unread) reads))
 505         (while children
 506           (incf unread (gnus-topic-unread (caar (pop children)))))
 507         (while (setq entry (pop entries))
 508           (when (numberp (car entry))
 509             (incf unread (car entry)))))
 510       (setq old-unread (gnus-group-topic-unread))
 511       ;; Insert the topic line.
 512       (gnus-topic-insert-topic-line
 513        (car type) (gnus-topic-visible-p)
 514        (not (eq (nth 2 type) 'hidden))
 515        (gnus-group-topic-level) all-entries unread)
 516       (gnus-delete-line))
 517     (when parent
 518       (forward-line -1)
 519       (gnus-topic-update-topic-line
 520        parent (- old-unread (gnus-group-topic-unread))))
 521     unread))
 522
 523 (defun gnus-topic-grok-active (&optional force)
 524   "Parse all active groups and create topic structures for them."
 525   ;; First we make sure that we have really read the active file.
 526   (when (or force
 527             (not gnus-topic-active-alist))
 528     (let (groups)
 529       ;; Get a list of all groups available.
 530       (mapatoms (lambda (g) (when (symbol-value g)
 531                               (push (symbol-name g) groups)))
 532                 gnus-active-hashtb)
 533       (setq groups (sort groups 'string<))
 534       ;; Init the variables.
 535       (setq gnus-topic-active-topology (list (list "" 'visible)))
 536       (setq gnus-topic-active-alist nil)
 537       ;; Descend the top-level hierarchy.
 538       (gnus-topic-grok-active-1 gnus-topic-active-topology groups)
 539       ;; Set the top-level topic names to something nice.
 540       (setcar (car gnus-topic-active-topology) "Gnus active")
 541       (setcar (car gnus-topic-active-alist) "Gnus active"))))
 542
 543 (defun gnus-topic-grok-active-1 (topology groups)
 544   (let* ((name (caar topology))
 545          (prefix (concat "^" (regexp-quote name)))
 546          tgroups ntopology group)
 547     (while (and groups
 548                 (string-match prefix (setq group (car groups))))
 549       (if (not (string-match "\\." group (match-end 0)))
 550           ;; There are no further hierarchies here, so we just
 551           ;; enter this group into the list belonging to this
 552           ;; topic.
 553           (push (pop groups) tgroups)
 554         ;; New sub-hierarchy, so we add it to the topology.
 555         (nconc topology (list (setq ntopology
 556                                     (list (list (substring
 557                                                  group 0 (match-end 0))
 558                                                 'invisible)))))
 559         ;; Descend the hierarchy.
 560         (setq groups (gnus-topic-grok-active-1 ntopology groups))))
 561     ;; We remove the trailing "." from the topic name.
 562     (setq name
 563           (if (string-match "\\.$" name)
 564               (substring name 0 (match-beginning 0))
 565             name))
 566     ;; Add this topic and its groups to the topic alist.
 567     (push (cons name (nreverse tgroups)) gnus-topic-active-alist)
 568     (setcar (car topology) name)
 569     ;; We return the rest of the groups that didn't belong
 570     ;; to this topic.
 571     groups))
 572
 573 (defun gnus-group-active-topic-p ()
 574   "Return whether the current active comes from the active topics."
 575   (save-excursion
 576     (beginning-of-line)
 577     (get-text-property (point) 'gnus-active)))
 578
 579 ;;; Topic mode, commands and keymap.
 580
 581 (defvar gnus-topic-mode-map nil)
 582 (defvar gnus-group-topic-map nil)
 583
 584 (unless gnus-topic-mode-map
 585   (setq gnus-topic-mode-map (make-sparse-keymap))
 586
 587   ;; Override certain group mode keys.
 588   (gnus-define-keys
 589    gnus-topic-mode-map
 590    "=" gnus-topic-select-group
 591    "\r" gnus-topic-select-group
 592    " " gnus-topic-read-group
 593    "\C-k" gnus-topic-kill-group
 594    "\C-y" gnus-topic-yank-group
 595    "\M-g" gnus-topic-get-new-news-this-topic
 596    "AT" gnus-topic-list-active
 597    gnus-mouse-2 gnus-mouse-pick-topic)
 598
 599   ;; Define a new submap.
 600   (gnus-define-keys
 601    (gnus-group-topic-map "T" gnus-group-mode-map)
 602    "#" gnus-topic-mark-topic
 603    "\M-#" gnus-topic-unmark-topic
 604    "n" gnus-topic-create-topic
 605    "m" gnus-topic-move-group
 606    "D" gnus-topic-remove-group
 607    "c" gnus-topic-copy-group
 608    "h" gnus-topic-hide-topic
 609    "s" gnus-topic-show-topic
 610    "M" gnus-topic-move-matching
 611    "C" gnus-topic-copy-matching
 612    "\C-i" gnus-topic-indent
 613    [tab] gnus-topic-indent
 614    "r" gnus-topic-rename
 615    "\177" gnus-topic-delete))
 616
 617 (defun gnus-topic-make-menu-bar ()
 618   (unless (boundp 'gnus-topic-menu)
 619     (easy-menu-define
 620      gnus-topic-menu gnus-topic-mode-map ""
 621      '("Topics"
 622        ["Toggle topics" gnus-topic-mode t]
 623        ("Groups"
 624         ["Copy" gnus-topic-copy-group t]
 625         ["Move" gnus-topic-move-group t]
 626         ["Remove" gnus-topic-remove-group t]
 627         ["Copy matching" gnus-topic-copy-matching t]
 628         ["Move matching" gnus-topic-move-matching t])
 629        ("Topics"
 630         ["Show" gnus-topic-show-topic t]
 631         ["Hide" gnus-topic-hide-topic t]
 632         ["Delete" gnus-topic-delete t]
 633         ["Rename" gnus-topic-rename t]
 634         ["Create" gnus-topic-create-topic t]
 635         ["Mark" gnus-topic-mark-topic t]
 636         ["Indent" gnus-topic-indent t])
 637        ["List active" gnus-topic-list-active t]))))
 638
 639 (defun gnus-topic-mode (&optional arg redisplay)
 640   "Minor mode for topicsifying Gnus group buffers."
 641   (interactive (list current-prefix-arg t))
 642   (when (eq major-mode 'gnus-group-mode)
 643     (make-local-variable 'gnus-topic-mode)
 644     (setq gnus-topic-mode
 645           (if (null arg) (not gnus-topic-mode)
 646             (> (prefix-numeric-value arg) 0)))
 647     ;; Infest Gnus with topics.
 648     (when gnus-topic-mode
 649       (when (and menu-bar-mode
 650                  (gnus-visual-p 'topic-menu 'menu))
 651         (gnus-topic-make-menu-bar))
 652       (setq gnus-topic-line-format-spec
 653             (gnus-parse-format gnus-topic-line-format
 654                                gnus-topic-line-format-alist t))
 655       (unless (assq 'gnus-topic-mode minor-mode-alist)
 656         (push '(gnus-topic-mode " Topic") minor-mode-alist))
 657       (unless (assq 'gnus-topic-mode minor-mode-map-alist)
 658         (push (cons 'gnus-topic-mode gnus-topic-mode-map)
 659               minor-mode-map-alist))
 660       (add-hook 'gnus-summary-exit-hook 'gnus-topic-update-topic)
 661       (add-hook 'gnus-group-catchup-group-hook 'gnus-topic-update-topic)
 662       (add-hook 'gnus-group-update-group-hook 'gnus-topic-update-topic)
 663       (make-local-variable 'gnus-group-prepare-function)
 664       (setq gnus-group-prepare-function 'gnus-group-prepare-topics)
 665       (make-local-variable 'gnus-group-goto-next-group-function)
 666       (setq gnus-group-goto-next-group-function
 667             'gnus-topic-goto-next-group)
 668       (setq gnus-group-change-level-function 'gnus-topic-change-level)
 669       (setq gnus-goto-missing-group-function 'gnus-topic-goto-missing-group)
 670       (make-local-variable 'gnus-group-indentation-function)
 671       (setq gnus-group-indentation-function
 672             'gnus-topic-group-indentation)
 673       (setq gnus-topology-checked-p nil)
 674       ;; We check the topology.
 675       (when gnus-newsrc-alist
 676         (gnus-topic-check-topology))
 677       (run-hooks 'gnus-topic-mode-hook))
 678     ;; Remove topic infestation.
 679     (unless gnus-topic-mode
 680       (remove-hook 'gnus-summary-exit-hook 'gnus-topic-update-topic)
 681       (remove-hook 'gnus-group-change-level-function
 682                    'gnus-topic-change-level)
 683       (setq gnus-group-prepare-function 'gnus-group-prepare-flat))
 684     (when redisplay
 685       (gnus-group-list-groups))))
 686
 687 (defun gnus-topic-select-group (&optional all)
 688   "Select this newsgroup.
 689 No article is selected automatically.
 690 If ALL is non-nil, already read articles become readable.
 691 If ALL is a number, fetch this number of articles."
 692   (interactive "P")
 693   (if (gnus-group-topic-p)
 694       (let ((gnus-group-list-mode
 695              (if all (cons (if (numberp all) all 7) t) gnus-group-list-mode)))
 696         (gnus-topic-fold all))
 697     (gnus-group-select-group all)))
 698
 699 (defun gnus-mouse-pick-topic (e)
 700   "Select the group or topic under the mouse pointer."
 701   (interactive "e")
 702   (mouse-set-point e)
 703   (gnus-topic-read-group nil))
 704
 705 (defun gnus-topic-read-group (&optional all no-article group)
 706   "Read news in this newsgroup.
 707 If the prefix argument ALL is non-nil, already read articles become
 708 readable.  IF ALL is a number, fetch this number of articles.  If the
 709 optional argument NO-ARTICLE is non-nil, no article will be
 710 auto-selected upon group entry.  If GROUP is non-nil, fetch that
 711 group."
 712   (interactive "P")
 713   (if (gnus-group-topic-p)
 714       (let ((gnus-group-list-mode
 715              (if all (cons (if (numberp all) all 7) t) gnus-group-list-mode)))
 716         (gnus-topic-fold all))
 717     (gnus-group-read-group all no-article group)))
 718
 719 (defun gnus-topic-create-topic (topic parent &optional previous full-topic)
 720   (interactive
 721    (list
 722     (read-string "New topic: ")
 723     (gnus-group-parent-topic)))
 724   ;; Check whether this topic already exists.
 725   (when (gnus-topic-find-topology topic)
 726     (error "Topic aleady exists"))
 727   (unless parent
 728     (setq parent (caar gnus-topic-topology)))
 729   (let ((top (cdr (gnus-topic-find-topology parent)))
 730         (full-topic (or full-topic `((,topic visible)))))
 731     (unless top
 732       (error "No such parent topic: %s" parent))
 733     (if previous
 734         (progn
 735           (while (and (cdr top)
 736                       (not (equal (caaadr top) previous)))
 737             (setq top (cdr top)))
 738           (setcdr top (cons full-topic (cdr top))))
 739       (nconc top (list full-topic)))
 740     (unless (assoc topic gnus-topic-alist)
 741       (push (list topic) gnus-topic-alist)))
 742   (gnus-topic-enter-dribble)
 743   (gnus-group-list-groups)
 744   (gnus-topic-goto-topic topic))
 745
 746 (defun gnus-topic-move-group (n topic &optional copyp)
 747   "Move the next N groups to TOPIC.
 748 If COPYP, copy the groups instead."
 749   (interactive
 750    (list current-prefix-arg
 751          (completing-read "Move to topic: " gnus-topic-alist nil t)))
 752   (let ((groups (gnus-group-process-prefix n))
 753         (topicl (assoc topic gnus-topic-alist))
 754         entry)
 755     (mapcar (lambda (g)
 756               (gnus-group-remove-mark g)
 757               (when (and
 758                      (setq entry (assoc (gnus-group-parent-topic)
 759                                         gnus-topic-alist))
 760                      (not copyp))
 761                 (setcdr entry (gnus-delete-first g (cdr entry))))
 762               (nconc topicl (list g)))
 763             groups)
 764     (gnus-group-position-point))
 765   (gnus-topic-enter-dribble)
 766   (gnus-group-list-groups))
 767
 768 (defun gnus-topic-remove-group ()
 769   "Remove the current group from the topic."
 770   (interactive)
 771   (let ((topicl (assoc (gnus-group-parent-topic) gnus-topic-alist))
 772         (group (gnus-group-group-name))
 773         (buffer-read-only nil))
 774     (when (and topicl group)
 775       (gnus-delete-line)
 776       (gnus-delete-first group topicl))
 777     (gnus-group-position-point)))
 778
 779 (defun gnus-topic-copy-group (n topic)
 780   "Copy the current group to a topic."
 781   (interactive
 782    (list current-prefix-arg
 783          (completing-read "Copy to topic: " gnus-topic-alist nil t)))
 784   (gnus-topic-move-group n topic t))
 785
 786 (defun gnus-topic-group-indentation ()
 787   (make-string
 788    (* gnus-topic-indent-level
 789       (or (save-excursion
 790             (gnus-topic-goto-topic (gnus-group-parent-topic))
 791             (gnus-group-topic-level)) 0)) ? ))
 792
 793 (defun gnus-topic-change-level (group level oldlevel)
 794   "Run when changing levels to enter/remove groups from topics."
 795   (save-excursion
 796     (set-buffer gnus-group-buffer)
 797     (when (and gnus-topic-mode
 798                gnus-topic-alist
 799                (not gnus-topic-inhibit-change-level))
 800       ;; Remove the group from the topics.
 801       (when (and (< oldlevel gnus-level-zombie)
 802                  (>= level gnus-level-zombie))
 803         (let (alist)
 804           (forward-line -1)
 805           (when (setq alist (assoc (gnus-group-parent-topic) gnus-topic-alist))
 806             (setcdr alist (gnus-delete-first group (cdr alist))))))
 807       ;; If the group is subscribed. then we enter it into the topics.
 808       (when (and (< level gnus-level-zombie)
 809                  (>= oldlevel gnus-level-zombie))
 810         (let* ((prev (gnus-group-group-name))
 811                (gnus-topic-inhibit-change-level t)
 812                (gnus-group-indentation
 813                 (make-string
 814                  (* gnus-topic-indent-level
 815                     (or (save-excursion
 816                           (gnus-topic-goto-topic (gnus-group-parent-topic))
 817                           (gnus-group-topic-level)) 0)) ? ))
 818                (yanked (list group))
 819                alist talist end)
 820           ;; Then we enter the yanked groups into the topics they belong
 821           ;; to.
 822           (when (setq alist (assoc (save-excursion
 823                                      (forward-line -1)
 824                                      (or
 825                                       (gnus-group-parent-topic)
 826                                       (caar gnus-topic-topology)))
 827                                    gnus-topic-alist))
 828             (setq talist alist)
 829             (when (stringp yanked)
 830               (setq yanked (list yanked)))
 831             (if (not prev)
 832                 (nconc alist yanked)
 833               (if (not (cdr alist))
 834                   (setcdr alist (nconc yanked (cdr alist)))
 835                 (while (and (not end) (cdr alist))
 836                   (when (equal (cadr alist) prev)
 837                     (setcdr alist (nconc yanked (cdr alist)))
 838                     (setq end t))
 839                   (setq alist (cdr alist)))
 840                 (unless end
 841                   (nconc talist yanked))))))
 842         (gnus-topic-update-topic)))))
 843
 844 (defun gnus-topic-goto-next-group (group props)
 845   "Go to group or the next group after group."
 846   (if (null group)
 847       (gnus-topic-goto-topic (symbol-name (cadr (memq 'gnus-topic props))))
 848     (if (gnus-group-goto-group group)
 849         t
 850       ;; The group is no longer visible.
 851       (let* ((list (assoc (gnus-group-parent-topic) gnus-topic-alist))
 852              (after (cdr (member group (cdr list)))))
 853         ;; First try to put point on a group after the current one.
 854         (while (and after
 855                     (not (gnus-group-goto-group (car after))))
 856           (setq after (cdr after)))
 857         ;; Then try to put point on a group before point.
 858         (unless after
 859           (setq after (cdr (member group (reverse (cdr list)))))
 860           (while (and after
 861                       (not (gnus-group-goto-group (car after))))
 862             (setq after (cdr after))))
 863         ;; Finally, just put point on the topic.
 864         (unless after
 865           (gnus-topic-goto-topic (car list))
 866           (setq after nil))
 867         t))))
 868
 869 (defun gnus-topic-kill-group (&optional n discard)
 870   "Kill the next N groups."
 871   (interactive "P")
 872   (if (gnus-group-topic-p)
 873       (let ((topic (gnus-group-topic-name)))
 874         (gnus-topic-remove-topic nil t)
 875         (push (gnus-topic-find-topology topic nil nil gnus-topic-topology)
 876               gnus-topic-killed-topics))
 877     (gnus-group-kill-group n discard)
 878     (gnus-topic-update-topic)))
 879
 880 (defun gnus-topic-yank-group (&optional arg)
 881   "Yank the last topic."
 882   (interactive "p")
 883   (if gnus-topic-killed-topics
 884       (let ((previous
 885              (or (gnus-group-topic-name)
 886                  (gnus-topic-next-topic (gnus-group-parent-topic))))
 887             (item (cdr (pop gnus-topic-killed-topics))))
 888         (gnus-topic-create-topic
 889          (caar item) (gnus-topic-parent-topic previous) previous
 890          item)
 891         (gnus-topic-goto-topic (caar item)))
 892     (let* ((prev (gnus-group-group-name))
 893            (gnus-topic-inhibit-change-level t)
 894            (gnus-group-indentation
 895             (make-string
 896              (* gnus-topic-indent-level
 897                 (or (save-excursion
 898                       (gnus-topic-goto-topic (gnus-group-parent-topic))
 899                       (gnus-group-topic-level)) 0)) ? ))
 900            yanked alist)
 901       ;; We first yank the groups the normal way...
 902       (setq yanked (gnus-group-yank-group arg))
 903       ;; Then we enter the yanked groups into the topics they belong
 904       ;; to.
 905       (setq alist (assoc (save-excursion
 906                            (forward-line -1)
 907                            (gnus-group-parent-topic))
 908                          gnus-topic-alist))
 909       (when (stringp yanked)
 910         (setq yanked (list yanked)))
 911       (if (not prev)
 912           (nconc alist yanked)
 913         (if (not (cdr alist))
 914             (setcdr alist (nconc yanked (cdr alist)))
 915           (while (cdr alist)
 916             (when (equal (cadr alist) prev)
 917               (setcdr alist (nconc yanked (cdr alist)))
 918               (setq alist nil))
 919             (setq alist (cdr alist))))))
 920     (gnus-topic-update-topic)))
 921
 922 (defun gnus-topic-hide-topic ()
 923   "Hide all subtopics under the current topic."
 924   (interactive)
 925   (when (gnus-group-parent-topic)
 926     (gnus-topic-goto-topic (gnus-group-parent-topic))
 927     (gnus-topic-remove-topic nil nil 'hidden)))
 928
 929 (defun gnus-topic-show-topic ()
 930   "Show the hidden topic."
 931   (interactive)
 932   (when (gnus-group-topic-p)
 933     (gnus-topic-remove-topic t nil 'shown)))
 934
 935 (defun gnus-topic-mark-topic (topic &optional unmark)
 936   "Mark all groups in the topic with the process mark."
 937   (interactive (list (gnus-group-parent-topic)))
 938   (save-excursion
 939     (let ((groups (gnus-topic-find-groups topic 9 t)))
 940       (while groups
 941         (funcall (if unmark 'gnus-group-remove-mark 'gnus-group-set-mark)
 942                  (gnus-info-group (nth 2 (pop groups))))))))
 943
 944 (defun gnus-topic-unmark-topic (topic &optional unmark)
 945   "Remove the process mark from all groups in the topic."
 946   (interactive (list (gnus-group-parent-topic)))
 947   (gnus-topic-mark-topic topic t))
 948
 949 (defun gnus-topic-get-new-news-this-topic (&optional n)
 950   "Check for new news in the current topic."
 951   (interactive "P")
 952   (if (not (gnus-group-topic-p))
 953       (gnus-group-get-new-news-this-group n)
 954     (gnus-topic-mark-topic (gnus-group-topic-name))
 955     (gnus-group-get-new-news-this-group)))
 956
 957 (defun gnus-topic-move-matching (regexp topic &optional copyp)
 958   "Move all groups that match REGEXP to some topic."
 959   (interactive
 960    (let (topic)
 961      (nreverse
 962       (list
 963        (setq topic (completing-read "Move to topic: " gnus-topic-alist nil t))
 964        (read-string (format "Move to %s (regexp): " topic))))))
 965   (gnus-group-mark-regexp regexp)
 966   (gnus-topic-move-group nil topic copyp))
 967
 968 (defun gnus-topic-copy-matching (regexp topic &optional copyp)
 969   "Copy all groups that match REGEXP to some topic."
 970   (interactive
 971    (let (topic)
 972      (nreverse
 973       (list
 974        (setq topic (completing-read "Copy to topic: " gnus-topic-alist nil t))
 975        (read-string (format "Copy to %s (regexp): " topic))))))
 976   (gnus-topic-move-matching regexp topic t))
 977
 978 (defun gnus-topic-delete (topic)
 979   "Delete a topic."
 980   (interactive (list (gnus-group-topic-name)))
 981   (unless topic
 982     (error "No topic to be deleted"))
 983   (let ((entry (assoc topic gnus-topic-alist))
 984         (buffer-read-only nil))
 985     (when (cdr entry)
 986       (error "Topic not empty"))
 987     ;; Delete if visible.
 988     (when (gnus-topic-goto-topic topic)
 989       (gnus-delete-line))
 990     ;; Remove from alist.
 991     (setq gnus-topic-alist (delq entry gnus-topic-alist))
 992     ;; Remove from topology.
 993     (gnus-topic-find-topology topic nil nil 'delete)))
 994
 995 (defun gnus-topic-rename (old-name new-name)
 996   "Rename a topic."
 997   (interactive
 998    (let ((topic (gnus-group-parent-topic)))
 999      (list topic
1000            (read-string (format "Rename %s to: " topic)))))
1001   (let ((top (gnus-topic-find-topology old-name))
1002         (entry (assoc old-name gnus-topic-alist)))
1003     (when top
1004       (setcar (cadr top) new-name))
1005     (when entry
1006       (setcar entry new-name))
1007     (gnus-group-list-groups)))
1008
1009 (defun gnus-topic-indent (&optional unindent)
1010   "Indent a topic -- make it a sub-topic of the previous topic.
1011 If UNINDENT, remove an indentation."
1012   (interactive "P")
1013   (if unindent
1014       (gnus-topic-unindent)
1015     (let* ((topic (gnus-group-parent-topic))
1016            (parent (gnus-topic-previous-topic topic)))
1017       (unless parent
1018         (error "Nothing to indent %s into" topic))
1019       (when topic
1020         (gnus-topic-goto-topic topic)
1021         (gnus-topic-kill-group)
1022         (gnus-topic-create-topic
1023          topic parent nil (cdr (pop gnus-topic-killed-topics)))
1024         (or (gnus-topic-goto-topic topic)
1025             (gnus-topic-goto-topic parent))))))
1026
1027 (defun gnus-topic-unindent ()
1028   "Unindent a topic."
1029   (interactive)
1030   (let* ((topic (gnus-group-parent-topic))
1031          (parent (gnus-topic-parent-topic topic))
1032          (grandparent (gnus-topic-parent-topic parent)))
1033     (unless grandparent
1034       (error "Nothing to indent %s into" topic))
1035     (when topic
1036       (gnus-topic-goto-topic topic)
1037       (gnus-topic-kill-group)
1038       (gnus-topic-create-topic
1039        topic grandparent (gnus-topic-next-topic parent)
1040        (cdr (pop gnus-topic-killed-topics)))
1041       (gnus-topic-goto-topic topic))))
1042
1043 (defun gnus-topic-list-active (&optional force)
1044   "List all groups that Gnus knows about in a topicsified fashion.
1045 If FORCE, always re-read the active file."
1046   (interactive "P")
1047   (when force
1048     (gnus-get-killed-groups))
1049   (gnus-topic-grok-active force)
1050   (let ((gnus-topic-topology gnus-topic-active-topology)
1051         (gnus-topic-alist gnus-topic-active-alist)
1052         gnus-killed-list gnus-zombie-list)
1053     (gnus-group-list-groups 9 nil 1)))
1054
1055 (provide 'gnus-topic)
1056
1057 ;;; gnus-topic.el ends here