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

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