[Emacs-diffs] Changes to emacs/lisp/gnus/html2text.el [gnus-5_10-branch]

[Andreas Schwab]

Index: emacs/lisp/gnus/html2text.el
diff -c /dev/null emacs/lisp/gnus/html2text.el:1.1.2.1
*** /dev/null   Thu Jul 22 16:46:47 2004
--- emacs/lisp/gnus/html2text.el        Thu Jul 22 16:45:49 2004
***************
*** 0 ****
--- 1,550 ----
+ ;;; html2text.el --- a simple html to plain text converter
+ ;; Copyright (C) 2002, 2003 Free Software Foundation, Inc.
+ 
+ ;; Author: Joakim Hove <address@hidden>
+ 
+ ;; This file is part of GNU Emacs.
+ 
+ ;; GNU Emacs is free software; you can redistribute it and/or modify
+ ;; it under the terms of the GNU General Public License as published by
+ ;; the Free Software Foundation; either version 2, or (at your option)
+ ;; any later version.
+ 
+ ;; GNU Emacs is distributed in the hope that it will be useful,
+ ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+ ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.        See the
+ ;; GNU General Public License for more details.
+ 
+ ;; You should have received a copy of the GNU General Public License
+ ;; along with GNU Emacs; see the file COPYING.  If not, write to the
+ ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ ;; Boston, MA 02111-1307, USA.
+ 
+ ;;; Commentary:
+ 
+ ;; These functions provide a simple way to wash/clean html infected
+ ;; mails.  Definitely do not work in all cases, but some improvement
+ ;; in readability is generally obtained. Formatting is only done in
+ ;; the buffer, so the next time you enter the article it will be
+ ;; "re-htmlized".
+ ;;
+ ;; The main function is "html2text"
+ 
+ ;;; Code:
+ 
+ ;;
+ ;; <Global variables>
+ ;;
+ 
+ (eval-when-compile
+   (require 'cl))
+ 
+ (defvar html2text-format-single-element-list '(("hr" . html2text-clean-hr)))
+ 
+ (defvar html2text-replace-list
+   '(("&nbsp;" . " ") ("&gt;" . ">") ("&lt;" . "<") ("&quot;" . "\""))
+   "The map of entity to text.
+ 
+ This is an alist were each element is a dotted pair consisting of an
+ old string, and a replacement string. This replacement is done by the
+ function \"html2text-substitute\" which basically performs a
+ replace-string operation for every element in the list. This is
+ completely verbatim - without any use of REGEXP.")
+ 
+ (defvar html2text-remove-tag-list
+   '("html" "body" "p" "img" "dir" "head" "div" "br" "font" "title" "meta")
+   "A list of removable tags.
+ 
+ This is a list of tags which should be removed, without any
+ formatting.  Observe that if you the tags in the list are presented
+ *without* any \"<\" or \">\". All occurences of a tag appearing in
+ this list are removed, irrespective of whether it is a closing or
+ opening tag, or if the tag has additional attributes. The actual
+ deletion is done by the function \"html2text-remove-tags\".
+ 
+ For instance the text:
+ 
+ \"Here comes something <font size\"+3\" face=\"Helvetica\"> big </font>.\"
+ 
+ will be reduced to:
+ 
+ \"Here comes something big.\"
+ 
+ If this list contains the element \"font\".")
+ 
+ (defvar html2text-format-tag-list
+   '(("b"        . html2text-clean-bold)
+     ("u"        . html2text-clean-underline)
+     ("i"        . html2text-clean-italic)
+     ("blockquote" . html2text-clean-blockquote)
+     ("a"          . html2text-clean-anchor)
+     ("ul"         . html2text-clean-ul)
+     ("ol"         . html2text-clean-ol)
+     ("dl"         . html2text-clean-dl)
+     ("center"     . html2text-clean-center))
+   "An alist of tags and processing functions.
+ 
+ This is an alist where each dotted pair consists of a tag, and then
+ the name of a function to be called when this tag is found. The
+ function is called with the arguments p1, p2, p3 and p4. These are
+ demontrated below:
+ 
+ \"<b> This is bold text </b>\"
+  ^   ^                 ^    ^
+  |   |                 |    |
+ p1  p2                p3   p4
+ 
+ Then the called function will typically format the text somewhat and
+ remove the tags.")
+ 
+ (defvar html2text-remove-tag-list2  '("li" "dt" "dd" "meta")
+   "Another list of removable tags.
+ 
+ This is a list of tags which are removed similarly to the list
+ `html2text-remove-tag-list' - but these tags are retained for the
+ formatting, and then moved afterward.")
+ 
+ ;;
+ ;; </Global variables>
+ ;;
+ 
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ 
+ ;;
+ ;; <Utility functions>
+ ;;
+ 
+ (defun html2text-buffer-head ()
+   (if (string= mode-name "Article")
+       (beginning-of-buffer)
+     (beginning-of-buffer)
+     )
+   )
+ 
+ (defun html2text-replace-string (from-string to-string p1 p2)
+   (goto-char p1)
+   (let ((delta (- (string-width to-string) (string-width from-string)))
+       (change 0))
+     (while (search-forward from-string p2 t)
+       (replace-match to-string)
+       (setq change (+ change delta))
+       )
+     change
+     )
+   )
+ 
+ ;;
+ ;; </Utility functions>
+ ;;
+ 
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ 
+ ;;
+ ;; <Functions related to attributes> i.e. <font size=+3>
+ ;;
+ 
+ (defun html2text-attr-value (attr-list attr)
+   (nth 1 (assoc attr attr-list))
+   )
+ 
+ (defun html2text-get-attr (p1 p2 tag)
+   (goto-char p1)
+   (re-search-forward " +[^ ]" p2 t)
+   (let* ((attr-string (buffer-substring-no-properties (1- (point)) (1- p2)))
+        (tmp-list (split-string attr-string))
+        (attr-list)
+        (counter 0)
+        (prev (car tmp-list))
+        (this (nth 1 tmp-list))
+        (next (nth 2 tmp-list))
+        (index 1))
+ 
+     (cond
+      ;; size=3
+      ((string-match "[^ ]=[^ ]" prev)
+       (let ((attr  (nth 0 (split-string prev "=")))
+           (value (nth 1 (split-string prev "="))))
+       (setq attr-list (cons (list attr value) attr-list))
+       )
+       )
+      ;; size= 3
+      ((string-match "[^ ]=\\'" prev)
+       (setq attr-list (cons (list (substring prev 0 -1) this) attr-list))
+       )
+      )
+ 
+     (while (< index (length tmp-list))
+       (cond
+        ;; size=3
+        ((string-match "[^ ]=[^ ]" this)
+       (let ((attr  (nth 0 (split-string this "=")))
+             (value (nth 1 (split-string this "="))))
+         (setq attr-list (cons (list attr value) attr-list))
+         )
+       )
+        ;; size =3
+        ((string-match "\\`=[^ ]" this)
+       (setq attr-list (cons (list prev (substring this 1)) attr-list)))
+ 
+        ;; size= 3
+        ((string-match "[^ ]=\\'" this)
+       (setq attr-list (cons (list (substring this 0 -1) next) attr-list))
+       )
+ 
+        ;; size = 3
+        ((string= "=" this)
+       (setq attr-list (cons (list prev next) attr-list))
+       )
+        )
+       (setq index (1+ index))
+       (setq prev this)
+       (setq this next)
+       (setq next (nth (1+ index) tmp-list))
+       )
+ 
+     ;;
+     ;; Tags with no accompanying "=" i.e. value=nil
+     ;;
+     (setq prev (car tmp-list))
+     (setq this (nth 1 tmp-list))
+     (setq next (nth 2 tmp-list))
+     (setq index 1)
+ 
+     (if (not (string-match "=" prev))
+       (progn
+         (if (not (string= (substring this 0 1) "="))
+             (setq attr-list (cons (list prev nil) attr-list))
+           )
+         )
+       )
+ 
+     (while (< index (1- (length tmp-list)))
+       (if (not (string-match "=" this))
+         (if (not (or (string= (substring next 0 1) "=")
+                      (string= (substring prev -1) "=")))
+             (setq attr-list (cons (list this nil) attr-list))
+           )
+       )
+       (setq index (1+ index))
+       (setq prev this)
+       (setq this next)
+       (setq next (nth (1+ index) tmp-list))
+       )
+ 
+     (if this
+       (progn
+         (if (not (string-match "=" this))
+             (progn
+               (if (not (string= (substring prev -1) "="))
+                   (setq attr-list (cons (list this nil) attr-list))
+                 )
+               )
+           )
+         )
+       )
+     attr-list ;; return - value
+     )
+   )
+ 
+ ;;
+ ;; </Functions related to attributes>
+ ;;
+ 
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ 
+ ;;
+ ;; <Functions to be called to format a tag-pair>
+ ;;
+ (defun html2text-clean-list-items (p1 p2 list-type)
+   (goto-char p1)
+   (let ((item-nr 0)
+       (items   0))
+     (while (re-search-forward "<li>" p2 t)
+       (setq items (1+ items)))
+     (goto-char p1)
+     (while (< item-nr items)
+       (setq item-nr (1+ item-nr))
+       (re-search-forward "<li>" (point-max) t)
+       (cond
+        ((string= list-type "ul") (insert " o "))
+        ((string= list-type "ol") (insert (format " %s: " item-nr)))
+        (t (insert " x ")))
+       )
+     )
+   )
+ 
+ (defun html2text-clean-dtdd (p1 p2)
+   (goto-char p1)
+   (let ((items   0)
+       (item-nr 0))
+     (while (re-search-forward "<dt>" p2 t)
+       (setq items (1+ items)))
+     (goto-char p1)
+     (while (< item-nr items)
+       (setq item-nr (1+ item-nr))
+       (re-search-forward "<dt>\\([ ]*\\)" (point-max) t)
+       (when (match-string 1)
+       (delete-region (point) (- (point) (string-width (match-string 1)))))
+       (let ((def-p1 (point))
+           (def-p2 0))
+       (re-search-forward "\\([ ]*\\)\\(</dt>\\|<dd>\\)" (point-max) t)
+       (if (match-string 1)
+           (progn
+             (let* ((mw1 (string-width (match-string 1)))
+                    (mw2 (string-width (match-string 2)))
+                    (mw  (+ mw1 mw2)))
+               (goto-char (- (point) mw))
+               (delete-region (point) (+ (point) mw1))
+               (setq def-p2 (point))))
+         (setq def-p2 (- (point) (string-width (match-string 2)))))
+       (put-text-property def-p1 def-p2 'face 'bold)))))
+ 
+ (defun html2text-delete-tags (p1 p2 p3 p4)
+   (delete-region p1 p2)
+   (delete-region (- p3 (- p2 p1)) (- p4 (- p2 p1))))
+ 
+ (defun html2text-delete-single-tag (p1 p2)
+   (delete-region p1 p2))
+ 
+ (defun html2text-clean-hr (p1 p2)
+   (html2text-delete-single-tag p1 p2)
+   (goto-char p1)
+   (newline 1)
+   (insert (make-string fill-column ?-))
+   )
+ 
+ (defun html2text-clean-ul (p1 p2 p3 p4)
+   (html2text-delete-tags p1 p2 p3 p4)
+   (html2text-clean-list-items p1 (- p3 (- p1 p2)) "ul")
+   )
+ 
+ (defun html2text-clean-ol (p1 p2 p3 p4)
+   (html2text-delete-tags p1 p2 p3 p4)
+   (html2text-clean-list-items p1 (- p3 (- p1 p2)) "ol")
+   )
+ 
+ (defun html2text-clean-dl (p1 p2 p3 p4)
+   (html2text-delete-tags p1 p2 p3 p4)
+   (html2text-clean-dtdd p1 (- p3 (- p1 p2)))
+   )
+ 
+ (defun html2text-clean-center (p1 p2 p3 p4)
+   (html2text-delete-tags p1 p2 p3 p4)
+   (center-region p1 (- p3 (- p2 p1)))
+   )
+ 
+ (defun html2text-clean-bold (p1 p2 p3 p4)
+   (put-text-property p2 p3 'face 'bold)
+   (html2text-delete-tags p1 p2 p3 p4)
+   )
+ 
+ (defun html2text-clean-title (p1 p2 p3 p4)
+   (put-text-property p2 p3 'face 'bold)
+   (html2text-delete-tags p1 p2 p3 p4)
+   )
+ 
+ (defun html2text-clean-underline (p1 p2 p3 p4)
+   (put-text-property p2 p3 'face 'underline)
+   (html2text-delete-tags p1 p2 p3 p4)
+   )
+ 
+ (defun html2text-clean-italic (p1 p2 p3 p4)
+   (put-text-property p2 p3 'face 'italic)
+   (html2text-delete-tags p1 p2 p3 p4)
+   )
+ 
+ (defun html2text-clean-font (p1 p2 p3 p4)
+   (html2text-delete-tags p1 p2 p3 p4)
+   )
+ 
+ (defun html2text-clean-blockquote (p1 p2 p3 p4)
+   (html2text-delete-tags p1 p2 p3 p4)
+   )
+ 
+ (defun html2text-clean-anchor (p1 p2 p3 p4)
+   ;; If someone can explain how to make the URL clickable I will
+   ;; surely improve upon this.
+   (let* ((attr-list (html2text-get-attr p1 p2 "a"))
+        (href (html2text-attr-value attr-list "href")))
+     (delete-region p1 p4)
+     (when href
+       (goto-char p1)
+       (insert (substring href 1 -1 ))
+       (put-text-property p1 (point) 'face 'bold))))
+ 
+ ;;
+ ;; </Functions to be called to format a tag-pair>
+ ;;
+ 
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ 
+ ;;
+ ;; <Functions to be called to fix up paragraphs>
+ ;;
+ 
+ (defun html2text-fix-paragraph (p1 p2)
+   (goto-char p1)
+   (let ((has-br-line)
+       (refill-start)
+       (refill-stop))
+     (if (re-search-forward "<br>$" p2 t)
+       (setq has-br-line t)
+       )
+     (if has-br-line
+       (progn
+         (goto-char p1)
+         (if (re-search-forward ".+[^<][^b][^r][^>]$" p2 t)
+             (progn
+               (beginning-of-line)
+               (setq refill-start (point))
+               (goto-char p2)
+               (re-search-backward ".+[^<][^b][^r][^>]$" refill-start t)
+               (next-line 1)
+               (end-of-line)
+               ;; refill-stop should ideally be adjusted to
+               ;; accomodate the "<br>" strings which are removed
+               ;; between refill-start and refill-stop.  Can simply
+               ;; be returned from my-replace-string
+               (setq refill-stop (+ (point)
+                                    (html2text-replace-string
+                                     "<br>" ""
+                                     refill-start (point))))
+               ;; (message "Point = %s  refill-stop = %s" (point) refill-stop)
+               ;; (sleep-for 4)
+               (fill-region refill-start refill-stop)
+               )
+           )
+         )
+       )
+     )
+   (html2text-replace-string "<br>" "" p1 p2)
+   )
+ 
+ ;;
+ ;; This one is interactive ...
+ ;;
+ (defun html2text-fix-paragraphs ()
+   "This _tries_ to fix up the paragraphs - this is done in quite a ad-hook
+ fashion, quite close to pure guess-work. It does work in some cases though."
+   (interactive)
+   (html2text-buffer-head)
+   (replace-regexp "^<br>$" "")
+   ;; Removing lonely <br> on a single line, if they are left intact we
+   ;; dont have any paragraphs at all.
+   (html2text-buffer-head)
+   (while (not (eobp))
+     (let ((p1 (point)))
+       (forward-paragraph 1)
+       ;;(message "Kaller fix med p1=%s  p2=%s " p1 (1- (point))) (sleep-for 5)
+       (html2text-fix-paragraph p1 (1- (point)))
+       (goto-char p1)
+       (when (not (eobp))
+       (forward-paragraph 1)))))
+ 
+ ;;
+ ;; </Functions to be called to fix up paragraphs>
+ ;;
+ 
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+ 
+ ;;
+ ;; <Interactive functions>
+ ;;
+ 
+ (defun html2text-remove-tags (tag-list)
+   "Removes the tags listed in the list \"html2text-remove-tag-list\".
+ See the documentation for that variable."
+   (interactive)
+   (dolist (tag tag-list)
+     (html2text-buffer-head)
+     (while (re-search-forward (format "\\(</?%s[^>]*>\\)" tag) (point-max) t)
+       (delete-region (match-beginning 0) (match-end 0)))))
+ 
+ (defun html2text-format-tags ()
+   "See the variable \"html2text-format-tag-list\" for documentation"
+   (interactive)
+   (dolist (tag-and-function html2text-format-tag-list)
+     (let ((tag      (car tag-and-function))
+         (function (cdr tag-and-function)))
+       (html2text-buffer-head)
+       (while (re-search-forward (format "\\(<%s\\( [^>]*\\)?>\\)" tag)
+                               (point-max) t)
+       (let ((p1)
+             (p2 (point))
+             (p3) (p4)
+             (attr (match-string 1)))
+         (search-backward "<" (point-min) t)
+         (setq p1 (point))
+         (re-search-forward (format "</%s>" tag) (point-max) t)
+         (setq p4 (point))
+         (search-backward "</" (point-min) t)
+         (setq p3 (point))
+         (funcall function p1 p2 p3 p4)
+         (goto-char p1)
+         )
+       )
+       )
+     )
+   )
+ 
+ (defun html2text-substitute ()
+   "See the variable \"html2text-replace-list\" for documentation"
+   (interactive)
+   (dolist (e html2text-replace-list)
+     (html2text-buffer-head)
+     (let ((old-string (car e))
+         (new-string (cdr e)))
+       (html2text-replace-string old-string new-string (point-min) (point-max))
+       )
+     )
+   )
+ 
+ (defun html2text-format-single-elements ()
+   ""
+   (interactive)
+   (dolist (tag-and-function html2text-format-single-element-list)
+     (let ((tag      (car tag-and-function))
+         (function (cdr tag-and-function)))
+       (html2text-buffer-head)
+       (while (re-search-forward (format "\\(<%s\\( [^>]*\\)?>\\)" tag)
+                               (point-max) t)
+       (let ((p1)
+             (p2 (point)))
+         (search-backward "<" (point-min) t)
+         (setq p1 (point))
+         (funcall function p1 p2)
+         )
+       )
+       )
+     )
+   )
+ 
+ ;;
+ ;; Main function
+ ;;
+ 
+ ;;;###autoload
+ (defun html2text ()
+   "Convert HTML to plain text in the current buffer."
+   (interactive)
+   (save-excursion
+     (let ((case-fold-search t)
+         (buffer-read-only))
+       (html2text-remove-tags html2text-remove-tag-list)
+       (html2text-format-tags)
+       (html2text-remove-tags html2text-remove-tag-list2)
+       (html2text-substitute)
+       (html2text-format-single-elements)
+       (html2text-fix-paragraphs))))
+ 
+ ;;
+ ;; </Interactive functions>
+ ;;
+ 
+ ;;; arch-tag: e9e57b79-35d4-4de1-a647-e7e01fe56d1e
+ ;;; html2text.el ends here