code.delx.au - gnu-emacs/blob - lisp/gnus/gnus-cite.el

   1 ;;; gnus-cite.el --- parse citations in articles for Gnus
   2 ;; Copyright (C) 1995,96,97 Free Software Foundation, Inc.
   3
   4 ;; Author: Per Abrahamsen <abraham@iesd.auc.dk>
   5 ;; Keywords: news, mail
   6
   7 ;; This file is part of GNU Emacs.
   8
   9 ;; GNU Emacs is free software; you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation; either version 2, or (at your option)
  12 ;; any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  21 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  22 ;; Boston, MA 02111-1307, USA.
  23
  24 ;;; Commentary:
  25
  26 ;;; Code:
  27
  28 (eval-when-compile (require 'cl))
  29
  30 (require 'gnus)
  31 (require 'gnus-art)
  32 (require 'gnus-range)
  33
  34 ;;; Customization:
  35
  36 (defgroup gnus-cite nil
  37   "Citation."
  38   :prefix "gnus-cite-"
  39   :link '(custom-manual "(gnus)Article Highlighting")
  40   :group 'gnus-article)
  41
  42 (defcustom gnus-cite-reply-regexp
  43   "^\\(Subject: Re\\|In-Reply-To\\|References\\):"
  44   "If headers match this regexp it is reasonable to believe that
  45 article has citations."
  46   :group 'gnus-cite
  47   :type 'string)
  48
  49 (defcustom gnus-cite-always-check nil
  50   "Check article always for citations. Set it t to check all articles."
  51   :group 'gnus-cite
  52   :type '(choice (const :tag "no" nil)
  53                   (const :tag "yes" t)))
  54
  55 (defcustom gnus-cited-text-button-line-format "%(%{[...]%}%)\n"
  56   "Format of cited text buttons."
  57   :group 'gnus-cite
  58   :type 'string)
  59
  60 (defcustom gnus-cited-lines-visible nil
  61   "The number of lines of hidden cited text to remain visible."
  62   :group 'gnus-cite
  63   :type '(choice (const :tag "none" nil)
  64                  integer))
  65
  66 (defcustom gnus-cite-parse-max-size 25000
  67   "Maximum article size (in bytes) where parsing citations is allowed.
  68 Set it to nil to parse all articles."
  69   :group 'gnus-cite
  70   :type '(choice (const :tag "all" nil)
  71                  integer))
  72
  73 (defcustom gnus-cite-prefix-regexp
  74     "^[]>|:}+ ]*[]>|:}+]\\(.*>\\)?\\|^.*>"
  75   "Regexp matching the longest possible citation prefix on a line."
  76   :group 'gnus-cite
  77   :type 'regexp)
  78
  79 (defcustom gnus-cite-max-prefix 20
  80   "Maximum possible length for a citation prefix."
  81   :group 'gnus-cite
  82   :type 'integer)
  83
  84 (defcustom gnus-supercite-regexp
  85   (concat "^\\(" gnus-cite-prefix-regexp "\\)? *"
  86           ">>>>> +\"\\([^\"\n]+\\)\" +==")
  87   "Regexp matching normal Supercite attribution lines.
  88 The first grouping must match prefixes added by other packages."
  89   :group 'gnus-cite
  90   :type 'regexp)
  91
  92 (defcustom gnus-supercite-secondary-regexp "^.*\"\\([^\"\n]+\\)\" +=="
  93   "Regexp matching mangled Supercite attribution lines.
  94 The first regexp group should match the Supercite attribution."
  95   :group 'gnus-cite
  96   :type 'regexp)
  97
  98 (defcustom gnus-cite-minimum-match-count 2
  99   "Minimum number of identical prefixes before we believe it's a citation."
 100   :group 'gnus-cite
 101   :type 'integer)
 102
 103 (defcustom gnus-cite-attribution-prefix "in article\\|in <"
 104   "Regexp matching the beginning of an attribution line."
 105   :group 'gnus-cite
 106   :type 'regexp)
 107
 108 (defcustom gnus-cite-attribution-suffix
 109   "\\(wrote\\|writes\\|said\\|says\\):[ \t]*$"
 110   "Regexp matching the end of an attribution line.
 111 The text matching the first grouping will be used as a button."
 112   :group 'gnus-cite
 113   :type 'regexp)
 114
 115 (defface gnus-cite-attribution-face '((t
 116                                        (:underline t)))
 117   "Face used for attribution lines.")
 118
 119 (defcustom gnus-cite-attribution-face 'gnus-cite-attribution-face
 120   "Face used for attribution lines.
 121 It is merged with the face for the cited text belonging to the attribution."
 122   :group 'gnus-cite
 123   :type 'face)
 124
 125 (defface gnus-cite-face-1 '((((class color)
 126                               (background dark))
 127                              (:foreground "light blue"))
 128                             (((class color)
 129                               (background light))
 130                              (:foreground "MidnightBlue"))
 131                             (t
 132                              (:italic t)))
 133   "Citation face.")
 134
 135 (defface gnus-cite-face-2 '((((class color)
 136                               (background dark))
 137                              (:foreground "light cyan"))
 138                             (((class color)
 139                               (background light))
 140                              (:foreground "firebrick"))
 141                             (t
 142                              (:italic t)))
 143   "Citation face.")
 144
 145 (defface gnus-cite-face-3 '((((class color)
 146                               (background dark))
 147                              (:foreground "light yellow"))
 148                             (((class color)
 149                               (background light))
 150                              (:foreground "dark green"))
 151                             (t
 152                              (:italic t)))
 153   "Citation face.")
 154
 155 (defface gnus-cite-face-4 '((((class color)
 156                               (background dark))
 157                              (:foreground "light pink"))
 158                             (((class color)
 159                               (background light))
 160                              (:foreground "OrangeRed"))
 161                             (t
 162                              (:italic t)))
 163   "Citation face.")
 164
 165 (defface gnus-cite-face-5 '((((class color)
 166                               (background dark))
 167                              (:foreground "pale green"))
 168                             (((class color)
 169                               (background light))
 170                              (:foreground "dark khaki"))
 171                             (t
 172                              (:italic t)))
 173   "Citation face.")
 174
 175 (defface gnus-cite-face-6 '((((class color)
 176                               (background dark))
 177                              (:foreground "beige"))
 178                             (((class color)
 179                               (background light))
 180                              (:foreground "dark violet"))
 181                             (t
 182                              (:italic t)))
 183   "Citation face.")
 184
 185 (defface gnus-cite-face-7 '((((class color)
 186                               (background dark))
 187                              (:foreground "orange"))
 188                             (((class color)
 189                               (background light))
 190                              (:foreground "SteelBlue4"))
 191                             (t
 192                              (:italic t)))
 193   "Citation face.")
 194
 195 (defface gnus-cite-face-8 '((((class color)
 196                               (background dark))
 197                              (:foreground "magenta"))
 198                             (((class color)
 199                               (background light))
 200                              (:foreground "magenta"))
 201                             (t
 202                              (:italic t)))
 203   "Citation face.")
 204
 205 (defface gnus-cite-face-9 '((((class color)
 206                               (background dark))
 207                              (:foreground "violet"))
 208                             (((class color)
 209                               (background light))
 210                              (:foreground "violet"))
 211                             (t
 212                              (:italic t)))
 213   "Citation face.")
 214
 215 (defface gnus-cite-face-10 '((((class color)
 216                                (background dark))
 217                               (:foreground "medium purple"))
 218                              (((class color)
 219                                (background light))
 220                               (:foreground "medium purple"))
 221                              (t
 222                               (:italic t)))
 223   "Citation face.")
 224
 225 (defface gnus-cite-face-11 '((((class color)
 226                                (background dark))
 227                               (:foreground "turquoise"))
 228                              (((class color)
 229                                (background light))
 230                               (:foreground "turquoise"))
 231                              (t
 232                               (:italic t)))
 233   "Citation face.")
 234
 235 (defcustom gnus-cite-face-list
 236   '(gnus-cite-face-1 gnus-cite-face-2 gnus-cite-face-3 gnus-cite-face-4
 237     gnus-cite-face-5 gnus-cite-face-6 gnus-cite-face-7 gnus-cite-face-8
 238     gnus-cite-face-9 gnus-cite-face-10 gnus-cite-face-11)
 239   "List of faces used for highlighting citations.
 240
 241 When there are citations from multiple articles in the same message,
 242 Gnus will try to give each citation from each article its own face.
 243 This should make it easier to see who wrote what."
 244   :group 'gnus-cite
 245   :type '(repeat face))
 246
 247 (defcustom gnus-cite-hide-percentage 50
 248   "Only hide excess citation if above this percentage of the body."
 249   :group 'gnus-cite
 250   :type 'number)
 251
 252 (defcustom gnus-cite-hide-absolute 10
 253   "Only hide excess citation if above this number of lines in the body."
 254   :group 'gnus-cite
 255   :type 'integer)
 256
 257 ;;; Internal Variables:
 258
 259 (defvar gnus-cite-article nil)
 260
 261 (defvar gnus-cite-prefix-alist nil)
 262 ;; Alist of citation prefixes.
 263 ;; The cdr is a list of lines with that prefix.
 264
 265 (defvar gnus-cite-attribution-alist nil)
 266 ;; Alist of attribution lines.
 267 ;; The car is a line number.
 268 ;; The cdr is the prefix for the citation started by that line.
 269
 270 (defvar gnus-cite-loose-prefix-alist nil)
 271 ;; Alist of citation prefixes that have no matching attribution.
 272 ;; The cdr is a list of lines with that prefix.
 273
 274 (defvar gnus-cite-loose-attribution-alist nil)
 275 ;; Alist of attribution lines that have no matching citation.
 276 ;; Each member has the form (WROTE IN PREFIX TAG), where
 277 ;; WROTE: is the attribution line number
 278 ;; IN: is the line number of the previous line if part of the same attribution,
 279 ;; PREFIX: Is the citation prefix of the attribution line(s), and
 280 ;; TAG: Is a Supercite tag, if any.
 281
 282 (defvar gnus-cited-text-button-line-format-alist
 283   `((?b (marker-position beg) ?d)
 284     (?e (marker-position end) ?d)
 285     (?l (- end beg) ?d)))
 286 (defvar gnus-cited-text-button-line-format-spec nil)
 287
 288 ;;; Commands:
 289
 290 (defun gnus-article-highlight-citation (&optional force)
 291   "Highlight cited text.
 292 Each citation in the article will be highlighted with a different face.
 293 The faces are taken from `gnus-cite-face-list'.
 294 Attribution lines are highlighted with the same face as the
 295 corresponding citation merged with `gnus-cite-attribution-face'.
 296
 297 Text is considered cited if at least `gnus-cite-minimum-match-count'
 298 lines matches `gnus-cite-prefix-regexp' with the same prefix.
 299
 300 Lines matching `gnus-cite-attribution-suffix' and perhaps
 301 `gnus-cite-attribution-prefix' are considered attribution lines."
 302   (interactive (list 'force))
 303   (save-excursion
 304     (set-buffer gnus-article-buffer)
 305     (gnus-cite-parse-maybe force)
 306     (let ((buffer-read-only nil)
 307           (alist gnus-cite-prefix-alist)
 308           (faces gnus-cite-face-list)
 309           (inhibit-point-motion-hooks t)
 310           face entry prefix skip numbers number face-alist)
 311       ;; Loop through citation prefixes.
 312       (while alist
 313         (setq entry (car alist)
 314               alist (cdr alist)
 315               prefix (car entry)
 316               numbers (cdr entry)
 317               face (car faces)
 318               faces (or (cdr faces) gnus-cite-face-list)
 319               face-alist (cons (cons prefix face) face-alist))
 320         (while numbers
 321           (setq number (car numbers)
 322                 numbers (cdr numbers))
 323           (and (not (assq number gnus-cite-attribution-alist))
 324                (not (assq number gnus-cite-loose-attribution-alist))
 325                (gnus-cite-add-face number prefix face))))
 326       ;; Loop through attribution lines.
 327       (setq alist gnus-cite-attribution-alist)
 328       (while alist
 329         (setq entry (car alist)
 330               alist (cdr alist)
 331               number (car entry)
 332               prefix (cdr entry)
 333               skip (gnus-cite-find-prefix number)
 334               face (cdr (assoc prefix face-alist)))
 335         ;; Add attribution button.
 336         (goto-line number)
 337         (when (re-search-forward gnus-cite-attribution-suffix
 338                                  (save-excursion (end-of-line 1) (point))
 339                                  t)
 340           (gnus-article-add-button (match-beginning 1) (match-end 1)
 341                                    'gnus-cite-toggle prefix))
 342         ;; Highlight attribution line.
 343         (gnus-cite-add-face number skip face)
 344         (gnus-cite-add-face number skip gnus-cite-attribution-face))
 345       ;; Loop through attribution lines.
 346       (setq alist gnus-cite-loose-attribution-alist)
 347       (while alist
 348         (setq entry (car alist)
 349               alist (cdr alist)
 350               number (car entry)
 351               skip (gnus-cite-find-prefix number))
 352         (gnus-cite-add-face number skip gnus-cite-attribution-face)))))
 353
 354 (defun gnus-dissect-cited-text ()
 355   "Dissect the article buffer looking for cited text."
 356   (save-excursion
 357     (set-buffer gnus-article-buffer)
 358     (gnus-cite-parse-maybe)
 359     (let ((alist gnus-cite-prefix-alist)
 360           prefix numbers number marks m)
 361       ;; Loop through citation prefixes.
 362       (while alist
 363         (setq numbers (pop alist)
 364               prefix (pop numbers))
 365         (while numbers
 366           (setq number (pop numbers))
 367           (goto-char (point-min))
 368           (forward-line number)
 369           (push (cons (point-marker) "") marks)
 370           (while (and numbers
 371                       (= (1- number) (car numbers)))
 372             (setq number (pop numbers)))
 373           (goto-char (point-min))
 374           (forward-line (1- number))
 375           (push (cons (point-marker) prefix) marks)))
 376       ;; Skip to the beginning of the body.
 377       (goto-char (point-min))
 378       (search-forward "\n\n" nil t)
 379       (push (cons (point-marker) "") marks)
 380       ;; Find the end of the body.
 381       (goto-char (point-max))
 382       (gnus-article-search-signature)
 383       (push (cons (point-marker) "") marks)
 384       ;; Sort the marks.
 385       (setq marks (sort marks (lambda (m1 m2) (< (car m1) (car m2)))))
 386       (let ((omarks marks))
 387         (setq marks nil)
 388         (while (cdr omarks)
 389           (if (= (caar omarks) (caadr omarks))
 390               (progn
 391                 (unless (equal (cdar omarks) "")
 392                   (push (car omarks) marks))
 393                 (unless (equal (cdadr omarks) "")
 394                   (push (cadr omarks) marks))
 395                 (unless (and (equal (cdar omarks) "")
 396                              (equal (cdadr omarks) "")
 397                              (not (cddr omarks)))
 398                   (setq omarks (cdr omarks))))
 399             (push (car omarks) marks))
 400           (setq omarks (cdr omarks)))
 401         (when (car omarks)
 402           (push (car omarks) marks))
 403         (setq marks (setq m (nreverse marks)))
 404         (while (cddr m)
 405           (if (and (equal (cdadr m) "")
 406                    (equal (cdar m) (cdaddr m))
 407                    (goto-char (caadr m))
 408                    (forward-line 1)
 409                    (= (point) (caaddr m)))
 410               (setcdr m (cdddr m))
 411             (setq m (cdr m))))
 412         marks))))
 413
 414 (defun gnus-article-fill-cited-article (&optional force width)
 415   "Do word wrapping in the current article.
 416 If WIDTH (the numerical prefix), use that text width when filling."
 417   (interactive (list t current-prefix-arg))
 418   (save-excursion
 419     (set-buffer gnus-article-buffer)
 420     (let ((buffer-read-only nil)
 421           (inhibit-point-motion-hooks t)
 422           (marks (gnus-dissect-cited-text))
 423           (adaptive-fill-mode nil)
 424           (filladapt-mode nil)
 425           (fill-column (if width (prefix-numeric-value width) fill-column)))
 426       (save-restriction
 427         (while (cdr marks)
 428           (widen)
 429           (narrow-to-region (caar marks) (caadr marks))
 430           (let ((adaptive-fill-regexp
 431                  (concat "^" (regexp-quote (cdar marks)) " *"))
 432                 (fill-prefix (cdar marks)))
 433             (fill-region (point-min) (point-max)))
 434           (set-marker (caar marks) nil)
 435           (setq marks (cdr marks)))
 436         (when marks
 437           (set-marker (caar marks) nil))
 438         ;; All this information is now incorrect.
 439         (setq gnus-cite-prefix-alist nil
 440               gnus-cite-attribution-alist nil
 441               gnus-cite-loose-prefix-alist nil
 442               gnus-cite-loose-attribution-alist nil)))))
 443
 444 (defun gnus-article-hide-citation (&optional arg force)
 445   "Toggle hiding of all cited text except attribution lines.
 446 See the documentation for `gnus-article-highlight-citation'.
 447 If given a negative prefix, always show; if given a positive prefix,
 448 always hide."
 449   (interactive (append (gnus-article-hidden-arg) (list 'force)))
 450   (setq gnus-cited-text-button-line-format-spec
 451         (gnus-parse-format gnus-cited-text-button-line-format
 452                            gnus-cited-text-button-line-format-alist t))
 453   (save-excursion
 454     (set-buffer gnus-article-buffer)
 455     (cond
 456      ((gnus-article-check-hidden-text 'cite arg)
 457       t)
 458      ((gnus-article-text-type-exists-p 'cite)
 459       (let ((buffer-read-only nil))
 460         (gnus-article-hide-text-of-type 'cite)))
 461      (t
 462       (let ((buffer-read-only nil)
 463             (marks (gnus-dissect-cited-text))
 464             (inhibit-point-motion-hooks t)
 465             (props (nconc (list 'article-type 'cite)
 466                           gnus-hidden-properties))
 467             beg end)
 468         (while marks
 469           (setq beg nil
 470                 end nil)
 471           (while (and marks (string= (cdar marks) ""))
 472             (setq marks (cdr marks)))
 473           (when marks
 474             (setq beg (caar marks)))
 475           (while (and marks (not (string= (cdar marks) "")))
 476             (setq marks (cdr marks)))
 477           (when marks
 478             (setq end (caar marks)))
 479           ;; Skip past lines we want to leave visible.
 480           (when (and beg end gnus-cited-lines-visible)
 481             (goto-char beg)
 482             (forward-line gnus-cited-lines-visible)
 483             (if (>= (point) end)
 484                 (setq beg nil)
 485               (setq beg (point-marker))))
 486           (when (and beg end)
 487             (gnus-add-text-properties beg end props)
 488             (goto-char beg)
 489             (unless (save-excursion (search-backward "\n\n" nil t))
 490               (insert "\n"))
 491             (put-text-property
 492              (point)
 493              (progn
 494                (gnus-article-add-button
 495                 (point)
 496                 (progn (eval gnus-cited-text-button-line-format-spec) (point))
 497                 `gnus-article-toggle-cited-text (cons beg end))
 498                (point))
 499              'article-type 'annotation)
 500             (set-marker beg (point)))))))))
 501
 502 (defun gnus-article-toggle-cited-text (region)
 503   "Toggle hiding the text in REGION."
 504   (let (buffer-read-only)
 505     (funcall
 506      (if (text-property-any
 507           (car region) (1- (cdr region))
 508           (car gnus-hidden-properties) (cadr gnus-hidden-properties))
 509          'remove-text-properties 'gnus-add-text-properties)
 510      (car region) (cdr region) gnus-hidden-properties)))
 511
 512 (defun gnus-article-hide-citation-maybe (&optional arg force)
 513   "Toggle hiding of cited text that has an attribution line.
 514 If given a negative prefix, always show; if given a positive prefix,
 515 always hide.
 516 This will do nothing unless at least `gnus-cite-hide-percentage'
 517 percent and at least `gnus-cite-hide-absolute' lines of the body is
 518 cited text with attributions.  When called interactively, these two
 519 variables are ignored.
 520 See also the documentation for `gnus-article-highlight-citation'."
 521   (interactive (append (gnus-article-hidden-arg) (list 'force)))
 522   (unless (gnus-article-check-hidden-text 'cite arg)
 523     (save-excursion
 524       (set-buffer gnus-article-buffer)
 525       (gnus-cite-parse-maybe force)
 526       (goto-char (point-min))
 527       (search-forward "\n\n" nil t)
 528       (let ((start (point))
 529             (atts gnus-cite-attribution-alist)
 530             (buffer-read-only nil)
 531             (inhibit-point-motion-hooks t)
 532             (hiden 0)
 533             total)
 534         (goto-char (point-max))
 535         (gnus-article-search-signature)
 536         (setq total (count-lines start (point)))
 537         (while atts
 538           (setq hiden (+ hiden (length (cdr (assoc (cdar atts)
 539                                                    gnus-cite-prefix-alist))))
 540                 atts (cdr atts)))
 541         (when (or force
 542                   (and (> (* 100 hiden) (* gnus-cite-hide-percentage total))
 543                        (> hiden gnus-cite-hide-absolute)))
 544           (setq atts gnus-cite-attribution-alist)
 545           (while atts
 546             (setq total (cdr (assoc (cdar atts) gnus-cite-prefix-alist))
 547                   atts (cdr atts))
 548             (while total
 549               (setq hiden (car total)
 550                     total (cdr total))
 551               (goto-line hiden)
 552               (unless (assq hiden gnus-cite-attribution-alist)
 553                 (gnus-add-text-properties
 554                  (point) (progn (forward-line 1) (point))
 555                  (nconc (list 'article-type 'cite)
 556                         gnus-hidden-properties))))))))))
 557
 558 (defun gnus-article-hide-citation-in-followups ()
 559   "Hide cited text in non-root articles."
 560   (interactive)
 561   (save-excursion
 562     (set-buffer gnus-article-buffer)
 563     (let ((article (cdr gnus-article-current)))
 564       (unless (save-excursion
 565                 (set-buffer gnus-summary-buffer)
 566                 (gnus-article-displayed-root-p article))
 567         (gnus-article-hide-citation)))))
 568
 569 ;;; Internal functions:
 570
 571 (defun gnus-cite-parse-maybe (&optional force)
 572   ;; Parse if the buffer has changes since last time.
 573   (if (equal gnus-cite-article gnus-article-current)
 574       ()
 575     ;;Reset parser information.
 576     (setq gnus-cite-prefix-alist nil
 577           gnus-cite-attribution-alist nil
 578           gnus-cite-loose-prefix-alist nil
 579           gnus-cite-loose-attribution-alist nil)
 580     ;; Parse if not too large.
 581     (if (and (not force)
 582              gnus-cite-parse-max-size
 583              (> (buffer-size) gnus-cite-parse-max-size))
 584         ()
 585       (setq gnus-cite-article (cons (car gnus-article-current)
 586                                     (cdr gnus-article-current)))
 587       (gnus-cite-parse-wrapper))))
 588
 589 (defun gnus-cite-parse-wrapper ()
 590   ;; Wrap chopped gnus-cite-parse
 591   (goto-char (point-min))
 592   (unless (search-forward "\n\n" nil t)
 593     (goto-char (point-max)))
 594   (save-excursion
 595     (gnus-cite-parse-attributions))
 596   ;; Try to avoid check citation if there is no reason to believe
 597   ;; that article has citations
 598   (if (or gnus-cite-always-check
 599           (save-excursion
 600             (re-search-backward gnus-cite-reply-regexp nil t))
 601           gnus-cite-loose-attribution-alist)
 602       (progn (save-excursion
 603                (gnus-cite-parse))
 604              (save-excursion
 605                (gnus-cite-connect-attributions)))))
 606
 607 (defun gnus-cite-parse ()
 608   ;; Parse and connect citation prefixes and attribution lines.
 609
 610   ;; Parse current buffer searching for citation prefixes.
 611   (let ((line (1+ (count-lines (point-min) (point))))
 612         (case-fold-search t)
 613         (max (save-excursion
 614                (goto-char (point-max))
 615                (gnus-article-search-signature)
 616                (point)))
 617         alist entry start begin end numbers prefix)
 618     ;; Get all potential prefixes in `alist'.
 619     (while (< (point) max)
 620       ;; Each line.
 621       (setq begin (point)
 622             end (progn (beginning-of-line 2) (point))
 623             start end)
 624       (goto-char begin)
 625       ;; Ignore standard Supercite attribution prefix.
 626       (when (looking-at gnus-supercite-regexp)
 627         (if (match-end 1)
 628             (setq end (1+ (match-end 1)))
 629           (setq end (1+ begin))))
 630       ;; Ignore very long prefixes.
 631       (when (> end (+ (point) gnus-cite-max-prefix))
 632         (setq end (+ (point) gnus-cite-max-prefix)))
 633       (while (re-search-forward gnus-cite-prefix-regexp (1- end) t)
 634         ;; Each prefix.
 635         (setq end (match-end 0)
 636               prefix (buffer-substring begin end))
 637         (gnus-set-text-properties 0 (length prefix) nil prefix)
 638         (setq entry (assoc prefix alist))
 639         (if entry
 640             (setcdr entry (cons line (cdr entry)))
 641           (push (list prefix line) alist))
 642         (goto-char begin))
 643       (goto-char start)
 644       (setq line (1+ line)))
 645     ;; We got all the potential prefixes.  Now create
 646     ;; `gnus-cite-prefix-alist' containing the oldest prefix for each
 647     ;; line that appears at least gnus-cite-minimum-match-count
 648     ;; times.  First sort them by length.  Longer is older.
 649     (setq alist (sort alist (lambda (a b)
 650                               (> (length (car a)) (length (car b))))))
 651     (while alist
 652       (setq entry (car alist)
 653             prefix (car entry)
 654             numbers (cdr entry)
 655             alist (cdr alist))
 656       (cond ((null numbers)
 657              ;; No lines with this prefix that wasn't also part of
 658              ;; a longer prefix.
 659              )
 660             ((< (length numbers) gnus-cite-minimum-match-count)
 661              ;; Too few lines with this prefix.  We keep it a bit
 662              ;; longer in case it is an exact match for an attribution
 663              ;; line, but we don't remove the line from other
 664              ;; prefixes.
 665              (push entry gnus-cite-prefix-alist))
 666             (t
 667              (push entry
 668                    gnus-cite-prefix-alist)
 669              ;; Remove articles from other prefixes.
 670              (let ((loop alist)
 671                    current)
 672                (while loop
 673                  (setq current (car loop)
 674                        loop (cdr loop))
 675                  (setcdr current
 676                          (gnus-set-difference (cdr current) numbers)))))))))
 677
 678 (defun gnus-cite-parse-attributions ()
 679   (let (al-alist)
 680     ;; Parse attributions
 681     (while (re-search-forward gnus-cite-attribution-suffix (point-max) t)
 682       (let* ((start (match-beginning 0))
 683              (end (match-end 0))
 684              (wrote (count-lines (point-min) end))
 685              (prefix (gnus-cite-find-prefix wrote))
 686              ;; Check previous line for an attribution leader.
 687              (tag (progn
 688                     (beginning-of-line 1)
 689                     (when (looking-at gnus-supercite-secondary-regexp)
 690                       (buffer-substring (match-beginning 1)
 691                                         (match-end 1)))))
 692              (in (progn
 693                    (goto-char start)
 694                    (and (re-search-backward gnus-cite-attribution-prefix
 695                                             (save-excursion
 696                                               (beginning-of-line 0)
 697                                               (point))
 698                                             t)
 699                         (not (re-search-forward gnus-cite-attribution-suffix
 700                                                 start t))
 701                         (count-lines (point-min) (1+ (point)))))))
 702         (when (eq wrote in)
 703           (setq in nil))
 704         (goto-char end)
 705         ;; don't add duplicates
 706         (let ((al (buffer-substring (save-excursion (beginning-of-line 0)
 707                                                     (1+ (point)))
 708                                     end)))
 709           (if (not (assoc al al-alist))
 710               (progn
 711                 (push (list wrote in prefix tag)
 712                       gnus-cite-loose-attribution-alist)
 713                 (push (cons al t) al-alist))))))))
 714
 715 (defun gnus-cite-connect-attributions ()
 716   ;; Connect attributions to citations
 717
 718   ;; No citations have been connected to attribution lines yet.
 719   (setq gnus-cite-loose-prefix-alist (append gnus-cite-prefix-alist nil))
 720
 721   ;; Parse current buffer searching for attribution lines.
 722   ;; Find exact supercite citations.
 723   (gnus-cite-match-attributions 'small nil
 724                                 (lambda (prefix tag)
 725                                   (when tag
 726                                     (concat "\\`"
 727                                             (regexp-quote prefix) "[ \t]*"
 728                                             (regexp-quote tag) ">"))))
 729   ;; Find loose supercite citations after attributions.
 730   (gnus-cite-match-attributions 'small t
 731                                 (lambda (prefix tag)
 732                                   (when tag
 733                                     (concat "\\<"
 734                                             (regexp-quote tag)
 735                                             "\\>"))))
 736   ;; Find loose supercite citations anywhere.
 737   (gnus-cite-match-attributions 'small nil
 738                                 (lambda (prefix tag)
 739                                   (when tag
 740                                     (concat "\\<"
 741                                             (regexp-quote tag)
 742                                             "\\>"))))
 743   ;; Find nested citations after attributions.
 744   (gnus-cite-match-attributions 'small-if-unique t
 745                                 (lambda (prefix tag)
 746                                   (concat "\\`" (regexp-quote prefix) ".+")))
 747   ;; Find nested citations anywhere.
 748   (gnus-cite-match-attributions 'small nil
 749                                 (lambda (prefix tag)
 750                                   (concat "\\`" (regexp-quote prefix) ".+")))
 751   ;; Remove loose prefixes with too few lines.
 752   (let ((alist gnus-cite-loose-prefix-alist)
 753         entry)
 754     (while alist
 755       (setq entry (car alist)
 756             alist (cdr alist))
 757       (when (< (length (cdr entry)) gnus-cite-minimum-match-count)
 758         (setq gnus-cite-prefix-alist
 759               (delq entry gnus-cite-prefix-alist)
 760               gnus-cite-loose-prefix-alist
 761               (delq entry gnus-cite-loose-prefix-alist)))))
 762   ;; Find flat attributions.
 763   (gnus-cite-match-attributions 'first t nil)
 764   ;; Find any attributions (are we getting desperate yet?).
 765   (gnus-cite-match-attributions 'first nil nil))
 766
 767 (defun gnus-cite-match-attributions (sort after fun)
 768   ;; Match all loose attributions and citations (SORT AFTER FUN) .
 769   ;;
 770   ;; If SORT is `small', the citation with the shortest prefix will be
 771   ;; used, if it is `first' the first prefix will be used, if it is
 772   ;; `small-if-unique' the shortest prefix will be used if the
 773   ;; attribution line does not share its own prefix with other
 774   ;; loose attribution lines, otherwise the first prefix will be used.
 775   ;;
 776   ;; If AFTER is non-nil, only citations after the attribution line
 777   ;; will be considered.
 778   ;;
 779   ;; If FUN is non-nil, it will be called with the arguments (WROTE
 780   ;; PREFIX TAG) and expected to return a regular expression.  Only
 781   ;; citations whose prefix matches the regular expression will be
 782   ;; considered.
 783   ;;
 784   ;; WROTE is the attribution line number.
 785   ;; PREFIX is the attribution line prefix.
 786   ;; TAG is the Supercite tag on the attribution line.
 787   (let ((atts gnus-cite-loose-attribution-alist)
 788         (case-fold-search t)
 789         att wrote in prefix tag regexp limit smallest best size)
 790     (while atts
 791       (setq att (car atts)
 792             atts (cdr atts)
 793             wrote (nth 0 att)
 794             in (nth 1 att)
 795             prefix (nth 2 att)
 796             tag (nth 3 att)
 797             regexp (if fun (funcall fun prefix tag) "")
 798             size (cond ((eq sort 'small) t)
 799                        ((eq sort 'first) nil)
 800                        (t (< (length (gnus-cite-find-loose prefix)) 2)))
 801             limit (if after wrote -1)
 802             smallest 1000000
 803             best nil)
 804       (let ((cites gnus-cite-loose-prefix-alist)
 805             cite candidate numbers first compare)
 806         (while cites
 807           (setq cite (car cites)
 808                 cites (cdr cites)
 809                 candidate (car cite)
 810                 numbers (cdr cite)
 811                 first (apply 'min numbers)
 812                 compare (if size (length candidate) first))
 813           (and (> first limit)
 814                regexp
 815                (string-match regexp candidate)
 816                (< compare smallest)
 817                (setq best cite
 818                      smallest compare))))
 819       (if (null best)
 820           ()
 821         (setq gnus-cite-loose-attribution-alist
 822               (delq att gnus-cite-loose-attribution-alist))
 823         (push (cons wrote (car best)) gnus-cite-attribution-alist)
 824         (when in
 825           (push (cons in (car best)) gnus-cite-attribution-alist))
 826         (when (memq best gnus-cite-loose-prefix-alist)
 827           (let ((loop gnus-cite-prefix-alist)
 828                 (numbers (cdr best))
 829                 current)
 830             (setq gnus-cite-loose-prefix-alist
 831                   (delq best gnus-cite-loose-prefix-alist))
 832             (while loop
 833               (setq current (car loop)
 834                     loop (cdr loop))
 835               (if (eq current best)
 836                   ()
 837                 (setcdr current (gnus-set-difference (cdr current) numbers))
 838                 (when (null (cdr current))
 839                   (setq gnus-cite-loose-prefix-alist
 840                         (delq current gnus-cite-loose-prefix-alist)
 841                         atts (delq current atts)))))))))))
 842
 843 (defun gnus-cite-find-loose (prefix)
 844   ;; Return a list of loose attribution lines prefixed by PREFIX.
 845   (let* ((atts gnus-cite-loose-attribution-alist)
 846          att line lines)
 847     (while atts
 848       (setq att (car atts)
 849             line (car att)
 850             atts (cdr atts))
 851       (when (string-equal (gnus-cite-find-prefix line) prefix)
 852         (push line lines)))
 853     lines))
 854
 855 (defun gnus-cite-add-face (number prefix face)
 856   ;; At line NUMBER, ignore PREFIX and add FACE to the rest of the line.
 857   (when face
 858     (let ((inhibit-point-motion-hooks t)
 859           from to)
 860       (goto-line number)
 861       (unless (eobp);; Sometimes things become confused.
 862         (forward-char (length prefix))
 863         (skip-chars-forward " \t")
 864         (setq from (point))
 865         (end-of-line 1)
 866         (skip-chars-backward " \t")
 867         (setq to (point))
 868         (when (< from to)
 869           (gnus-overlay-put (gnus-make-overlay from to) 'face face))))))
 870
 871 (defun gnus-cite-toggle (prefix)
 872   (save-excursion
 873     (set-buffer gnus-article-buffer)
 874     (let ((buffer-read-only nil)
 875           (numbers (cdr (assoc prefix gnus-cite-prefix-alist)))
 876           (inhibit-point-motion-hooks t)
 877           number)
 878       (while numbers
 879         (setq number (car numbers)
 880               numbers (cdr numbers))
 881         (goto-line number)
 882         (cond ((get-text-property (point) 'invisible)
 883                (remove-text-properties (point) (progn (forward-line 1) (point))
 884                                        gnus-hidden-properties))
 885               ((assq number gnus-cite-attribution-alist))
 886               (t
 887                (gnus-add-text-properties
 888                 (point) (progn (forward-line 1) (point))
 889                 (nconc (list 'article-type 'cite)
 890                        gnus-hidden-properties))))))))
 891
 892 (defun gnus-cite-find-prefix (line)
 893   ;; Return citation prefix for LINE.
 894   (let ((alist gnus-cite-prefix-alist)
 895         (prefix "")
 896         entry)
 897     (while alist
 898       (setq entry (car alist)
 899             alist (cdr alist))
 900       (when (memq line (cdr entry))
 901         (setq prefix (car entry))))
 902     prefix))
 903
 904 (gnus-add-shutdown 'gnus-cache-close 'gnus)
 905
 906 (defun gnus-cache-close ()
 907   (setq gnus-cite-prefix-alist nil))
 908
 909 (gnus-ems-redefine)
 910
 911 (provide 'gnus-cite)
 912
 913 ;;; gnus-cite.el ends here