lisp/gnus/gnus-logic.el

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