lisp/gnus/gnus-logic.el

   1 ;;; gnus-logic.el --- advanced scoring code for Gnus
   2
   3 ;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   4 ;;   2005, 2006, 2007, 2008 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 3, 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 ;;; Code:
  29
  30 (eval-when-compile (require 'cl))
  31
  32 (require 'gnus)
  33 (require 'gnus-score)
  34 (require 'gnus-util)
  35
  36 ;;; Internal variables.
  37
  38 (defvar gnus-advanced-headers nil)
  39
  40 ;; To avoid having 8-bit characters in the source file.
  41 (defvar gnus-advanced-not (intern (format "%c" 172)))
  42
  43 (defconst gnus-advanced-index
  44   ;; Name to index alist.
  45   '(("number" 0 gnus-advanced-integer)
  46     ("subject" 1 gnus-advanced-string)
  47     ("from" 2 gnus-advanced-string)
  48     ("date" 3 gnus-advanced-date)
  49     ("message-id" 4 gnus-advanced-string)
  50     ("references" 5 gnus-advanced-string)
  51     ("chars" 6 gnus-advanced-integer)
  52     ("lines" 7 gnus-advanced-integer)
  53     ("xref" 8 gnus-advanced-string)
  54     ("head" nil gnus-advanced-body)
  55     ("body" nil gnus-advanced-body)
  56     ("all" nil gnus-advanced-body)))
  57
  58 (eval-and-compile
  59   (autoload 'parse-time-string "parse-time"))
  60
  61 (defun gnus-score-advanced (rule &optional trace)
  62   "Apply advanced scoring RULE to all the articles in the current group."
  63   (let (new-score score multiple)
  64     (dolist (gnus-advanced-headers gnus-newsgroup-headers)
  65       (when (setq multiple (gnus-advanced-score-rule (car rule)))
  66         (setq new-score (or (nth 1 rule)
  67                             gnus-score-interactive-default-score))
  68         (when (numberp multiple)
  69           (setq new-score (* multiple new-score)))
  70         ;; This rule was successful, so we add the score to this
  71         ;; article.
  72         (if (setq score (assq (mail-header-number gnus-advanced-headers)
  73                               gnus-newsgroup-scored))
  74             (setcdr score
  75                     (+ (cdr score) new-score))
  76           (push (cons (mail-header-number gnus-advanced-headers)
  77                       new-score)
  78                 gnus-newsgroup-scored)
  79           (when trace
  80             (push (cons "A file" rule)
  81                   ;; Must be synced with `gnus-score-edit-file-at-point'.
  82                   gnus-score-trace)))))))
  83
  84 (defun gnus-advanced-score-rule (rule)
  85   "Apply RULE to `gnus-advanced-headers'."
  86   (let ((type (car rule)))
  87     (cond
  88      ;; "And" rule.
  89      ((or (eq type '&) (eq type 'and))
  90       (pop rule)
  91       (if (not rule)
  92           t                             ; Empty rule is true.
  93         (while (and rule
  94                     (gnus-advanced-score-rule (car rule)))
  95           (pop rule))
  96         ;; If all the rules were true, then `rule' should be nil.
  97         (not rule)))
  98      ;; "Or" rule.
  99      ((or (eq type '|) (eq type 'or))
 100       (pop rule)
 101       (if (not rule)
 102           nil
 103         (while (and rule
 104                     (not (gnus-advanced-score-rule (car rule))))
 105           (pop rule))
 106         ;; If one of the rules returned true, then `rule' should be non-nil.
 107         rule))
 108      ;; "Not" rule.
 109      ((or (eq type '!) (eq type 'not) (eq type gnus-advanced-not))
 110       (not (gnus-advanced-score-rule (nth 1 rule))))
 111      ;; This is a `1-'-type redirection rule.
 112      ((and (symbolp type)
 113            (string-match "^[0-9]+-$\\|^\\^+$" (symbol-name type)))
 114       (let ((gnus-advanced-headers
 115              (gnus-parent-headers
 116               gnus-advanced-headers
 117               (if (string-match "^\\([0-9]+\\)-$" (symbol-name type))
 118                   ;; 1- type redirection.
 119                   (string-to-number
 120                    (substring (symbol-name type)
 121                               (match-beginning 1) (match-end 1)))
 122                 ;; ^^^ type redirection.
 123                 (length (symbol-name type))))))
 124         (when gnus-advanced-headers
 125           (gnus-advanced-score-rule (nth 1 rule)))))
 126      ;; Plain scoring rule.
 127      ((stringp type)
 128       (gnus-advanced-score-article rule))
 129      ;; Bug-out time!
 130      (t
 131       (error "Unknown advanced score type: %s" rule)))))
 132
 133 (defun gnus-advanced-score-article (rule)
 134   ;; `rule' is a semi-normal score rule, so we find out what function
 135   ;; that's supposed to do the actual processing.
 136   (let* ((header (car rule))
 137          (func (assoc (downcase header) gnus-advanced-index)))
 138     (if (not func)
 139         (error "No such header: %s" rule)
 140       ;; Call the score function.
 141       (funcall (caddr func) (or (cadr func) header)
 142                (cadr rule) (caddr rule)))))
 143
 144 (defun gnus-advanced-string (index match type)
 145   "See whether string MATCH of TYPE matches `gnus-advanced-headers' in INDEX."
 146   (let* ((type (or type 's))
 147          (case-fold-search (not (eq (downcase (symbol-name type))
 148                                     (symbol-name type))))
 149          (header (or (aref gnus-advanced-headers index) "")))
 150     (cond
 151      ((memq type '(r R regexp Regexp))
 152       (string-match match header))
 153      ((memq type '(s S string String))
 154       (string-match (regexp-quote match) header))
 155      ((memq type '(e E exact Exact))
 156       (string= match header))
 157      ((memq type '(f F fuzzy Fuzzy))
 158       (string-match (regexp-quote (gnus-simplify-subject-fuzzy match))
 159                     header))
 160      (t
 161       (error "No such string match type: %s" type)))))
 162
 163 (defun gnus-advanced-integer (index match type)
 164   (if (not (memq type '(< > <= >= =)))
 165       (error "No such integer score type: %s" type)
 166     (funcall type (or (aref gnus-advanced-headers index) 0) match)))
 167
 168 (defun gnus-advanced-date (index match type)
 169   (let ((date (apply 'encode-time (parse-time-string
 170                                    (aref gnus-advanced-headers index))))
 171         (match (apply 'encode-time (parse-time-string match))))
 172     (cond
 173      ((eq type 'at)
 174       (equal date match))
 175      ((eq type 'before)
 176       (time-less-p match date))
 177      ((eq type 'after)
 178       (time-less-p date match))
 179      (t
 180       (error "No such date score type: %s" type)))))
 181
 182 (defun gnus-advanced-body (header match type)
 183   (when (string= header "all")
 184     (setq header "article"))
 185   (save-excursion
 186     (set-buffer nntp-server-buffer)
 187     (let* ((request-func (cond ((string= "head" header)
 188                                 'gnus-request-head)
 189                                ((string= "body" header)
 190                                 'gnus-request-body)
 191                                (t 'gnus-request-article)))
 192            ofunc article)
 193       ;; Not all backends support partial fetching.  In that case, we
 194       ;; just fetch the entire article.
 195       (unless (gnus-check-backend-function
 196                (intern (concat "request-" header))
 197                gnus-newsgroup-name)
 198         (setq ofunc request-func)
 199         (setq request-func 'gnus-request-article))
 200       (setq article (mail-header-number gnus-advanced-headers))
 201       (gnus-message 7 "Scoring article %s..." article)
 202       (when (funcall request-func article gnus-newsgroup-name)
 203         (goto-char (point-min))
 204         ;; If just parts of the article is to be searched and the
 205         ;; backend didn't support partial fetching, we just narrow to
 206         ;; the relevant parts.
 207         (when ofunc
 208           (if (eq ofunc 'gnus-request-head)
 209               (narrow-to-region
 210                (point)
 211                (or (search-forward "\n\n" nil t) (point-max)))
 212             (narrow-to-region
 213              (or (search-forward "\n\n" nil t) (point))
 214              (point-max))))
 215         (let* ((case-fold-search (not (eq (downcase (symbol-name type))
 216                                           (symbol-name type))))
 217                (search-func
 218                 (cond ((memq type '(r R regexp Regexp))
 219                        're-search-forward)
 220                       ((memq type '(s S string String))
 221                        'search-forward)
 222                       (t
 223                        (error "Invalid match type: %s" type)))))
 224           (goto-char (point-min))
 225           (prog1
 226               (funcall search-func match nil t)
 227             (widen)))))))
 228
 229 (provide 'gnus-logic)
 230
 231 ;; arch-tag: 9651a100-4a59-4b69-a55b-e511e67c0f8d
 232 ;;; gnus-logic.el ends here