lisp/gnus/shr.el

   1 ;;; shr.el --- Simple HTML Renderer
   2
   3 ;; Copyright (C) 2010-2011 Free Software Foundation, Inc.
   4
   5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   6 ;; Keywords: html
   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 3 of the License, or
  13 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;; This package takes a HTML parse tree (as provided by
  26 ;; libxml-parse-html-region) and renders it in the current buffer.  It
  27 ;; does not do CSS, JavaScript or anything advanced: It's geared
  28 ;; towards rendering typical short snippets of HTML, like what you'd
  29 ;; find in HTML email and the like.
  30
  31 ;;; Code:
  32
  33 (eval-when-compile (require 'cl))
  34 (require 'browse-url)
  35
  36 (defgroup shr nil
  37   "Simple HTML Renderer"
  38   :group 'mail)
  39
  40 (defcustom shr-max-image-proportion 0.9
  41   "How big pictures displayed are in relation to the window they're in.
  42 A value of 0.7 means that they are allowed to take up 70% of the
  43 width and height of the window.  If they are larger than this,
  44 and Emacs supports it, then the images will be rescaled down to
  45 fit these criteria."
  46   :version "24.1"
  47   :group 'shr
  48   :type 'float)
  49
  50 (defcustom shr-blocked-images nil
  51   "Images that have URLs matching this regexp will be blocked."
  52   :version "24.1"
  53   :group 'shr
  54   :type 'regexp)
  55
  56 (defcustom shr-table-horizontal-line ?
  57   "Character used to draw horizontal table lines."
  58   :group 'shr
  59   :type 'character)
  60
  61 (defcustom shr-table-vertical-line ?
  62   "Character used to draw vertical table lines."
  63   :group 'shr
  64   :type 'character)
  65
  66 (defcustom shr-table-corner ?
  67   "Character used to draw table corners."
  68   :group 'shr
  69   :type 'character)
  70
  71 (defcustom shr-hr-line ?-
  72   "Character used to draw hr lines."
  73   :group 'shr
  74   :type 'character)
  75
  76 (defcustom shr-width fill-column
  77   "Frame width to use for rendering.
  78 May either be an integer specifying a fixed width in characters,
  79 or nil, meaning that the full width of the window should be
  80 used."
  81   :type '(choice (integer :tag "Fixed width in characters")
  82                  (const   :tag "Use the width of the window" nil))
  83   :group 'shr)
  84
  85 (defvar shr-content-function nil
  86   "If bound, this should be a function that will return the content.
  87 This is used for cid: URLs, and the function is called with the
  88 cid: URL as the argument.")
  89
  90 (defvar shr-put-image-function 'shr-put-image
  91   "Function called to put image and alt string.")
  92
  93 (defface shr-strike-through '((t (:strike-through t)))
  94   "Font for <s> elements."
  95   :group 'shr)
  96
  97 (defface shr-link
  98   '((t (:inherit link)))
  99   "Font for link elements."
 100   :group 'shr)
 101
 102 ;;; Internal variables.
 103
 104 (defvar shr-folding-mode nil)
 105 (defvar shr-state nil)
 106 (defvar shr-start nil)
 107 (defvar shr-indentation 0)
 108 (defvar shr-inhibit-images nil)
 109 (defvar shr-list-mode nil)
 110 (defvar shr-content-cache nil)
 111 (defvar shr-kinsoku-shorten nil)
 112 (defvar shr-table-depth 0)
 113 (defvar shr-stylesheet nil)
 114 (defvar shr-base nil)
 115
 116 (defvar shr-map
 117   (let ((map (make-sparse-keymap)))
 118     (define-key map "a" 'shr-show-alt-text)
 119     (define-key map "i" 'shr-browse-image)
 120     (define-key map "I" 'shr-insert-image)
 121     (define-key map "u" 'shr-copy-url)
 122     (define-key map "v" 'shr-browse-url)
 123     (define-key map "o" 'shr-save-contents)
 124     (define-key map "\r" 'shr-browse-url)
 125     map))
 126
 127 ;; Public functions and commands.
 128
 129 (defun shr-visit-file (file)
 130   (interactive "fHTML file name: ")
 131   (pop-to-buffer "*html*")
 132   (erase-buffer)
 133   (shr-insert-document
 134    (with-temp-buffer
 135      (insert-file-contents file)
 136      (libxml-parse-html-region (point-min) (point-max)))))
 137
 138 ;;;###autoload
 139 (defun shr-insert-document (dom)
 140   (setq shr-content-cache nil)
 141   (let ((shr-state nil)
 142         (shr-start nil)
 143         (shr-base nil)
 144         (shr-width (or shr-width (window-width))))
 145     (shr-descend (shr-transform-dom dom))))
 146
 147 (defun shr-copy-url ()
 148   "Copy the URL under point to the kill ring.
 149 If called twice, then try to fetch the URL and see whether it
 150 redirects somewhere else."
 151   (interactive)
 152   (let ((url (get-text-property (point) 'shr-url)))
 153     (cond
 154      ((not url)
 155       (message "No URL under point"))
 156      ;; Resolve redirected URLs.
 157      ((equal url (car kill-ring))
 158       (url-retrieve
 159        url
 160        (lambda (a)
 161          (when (and (consp a)
 162                     (eq (car a) :redirect))
 163            (with-temp-buffer
 164              (insert (cadr a))
 165              (goto-char (point-min))
 166              ;; Remove common tracking junk from the URL.
 167              (when (re-search-forward ".utm_.*" nil t)
 168                (replace-match "" t t))
 169              (message "Copied %s" (buffer-string))
 170              (copy-region-as-kill (point-min) (point-max)))))))
 171      ;; Copy the URL to the kill ring.
 172      (t
 173       (with-temp-buffer
 174         (insert url)
 175         (copy-region-as-kill (point-min) (point-max))
 176         (message "Copied %s" url))))))
 177
 178 (defun shr-show-alt-text ()
 179   "Show the ALT text of the image under point."
 180   (interactive)
 181   (let ((text (get-text-property (point) 'shr-alt)))
 182     (if (not text)
 183         (message "No image under point")
 184       (message "%s" text))))
 185
 186 (defun shr-browse-image ()
 187   "Browse the image under point."
 188   (interactive)
 189   (let ((url (get-text-property (point) 'image-url)))
 190     (if (not url)
 191         (message "No image under point")
 192       (message "Browsing %s..." url)
 193       (browse-url url))))
 194
 195 (defun shr-insert-image ()
 196   "Insert the image under point into the buffer."
 197   (interactive)
 198   (let ((url (get-text-property (point) 'image-url)))
 199     (if (not url)
 200         (message "No image under point")
 201       (message "Inserting %s..." url)
 202       (url-retrieve url 'shr-image-fetched
 203                     (list (current-buffer) (1- (point)) (point-marker))
 204                     t))))
 205
 206 ;;; Utility functions.
 207
 208 (defun shr-transform-dom (dom)
 209   (let ((result (list (pop dom))))
 210     (dolist (arg (pop dom))
 211       (push (cons (intern (concat ":" (symbol-name (car arg))) obarray)
 212                   (cdr arg))
 213             result))
 214     (dolist (sub dom)
 215       (if (stringp sub)
 216           (push (cons 'text sub) result)
 217         (push (shr-transform-dom sub) result)))
 218     (nreverse result)))
 219
 220 (defun shr-descend (dom)
 221   (let ((function (intern (concat "shr-tag-" (symbol-name (car dom))) obarray))
 222         (style (cdr (assq :style (cdr dom))))
 223         (shr-stylesheet shr-stylesheet)
 224         (start (point)))
 225     (when style
 226       (if (string-match "color" style)
 227           (setq shr-stylesheet (nconc (shr-parse-style style)
 228                                       shr-stylesheet))
 229         (setq style nil)))
 230     (if (fboundp function)
 231         (funcall function (cdr dom))
 232       (shr-generic (cdr dom)))
 233     ;; If style is set, then this node has set the color.
 234     (when style
 235       (shr-colorize-region start (point)
 236                            (cdr (assq 'color shr-stylesheet))
 237                            (cdr (assq 'background-color shr-stylesheet))))))
 238
 239 (defun shr-generic (cont)
 240   (dolist (sub cont)
 241     (cond
 242      ((eq (car sub) 'text)
 243       (shr-insert (cdr sub)))
 244      ((listp (cdr sub))
 245       (shr-descend sub)))))
 246
 247 (defmacro shr-char-breakable-p (char)
 248   "Return non-nil if a line can be broken before and after CHAR."
 249   `(aref fill-find-break-point-function-table ,char))
 250 (defmacro shr-char-nospace-p (char)
 251   "Return non-nil if no space is required before and after CHAR."
 252   `(aref fill-nospace-between-words-table ,char))
 253
 254 ;; KINSOKU is a Japanese word meaning a rule that should not be violated.
 255 ;; In Emacs, it is a term used for characters, e.g. punctuation marks,
 256 ;; parentheses, and so on, that should not be placed in the beginning
 257 ;; of a line or the end of a line.
 258 (defmacro shr-char-kinsoku-bol-p (char)
 259   "Return non-nil if a line ought not to begin with CHAR."
 260   `(aref (char-category-set ,char) ?>))
 261 (defmacro shr-char-kinsoku-eol-p (char)
 262   "Return non-nil if a line ought not to end with CHAR."
 263   `(aref (char-category-set ,char) ?<))
 264 (unless (shr-char-kinsoku-bol-p (make-char 'japanese-jisx0208 33 35))
 265   (load "kinsoku" nil t))
 266
 267 (defun shr-insert (text)
 268   (when (and (eq shr-state 'image)
 269              (not (string-match "\\`[ \t\n]+\\'" text)))
 270     (insert "\n")
 271     (setq shr-state nil))
 272   (cond
 273    ((eq shr-folding-mode 'none)
 274     (insert text))
 275    (t
 276     (when (and (string-match "\\`[ \t\n]" text)
 277                (not (bolp))
 278                (not (eq (char-after (1- (point))) ? )))
 279       (insert " "))
 280     (dolist (elem (split-string text))
 281       (when (and (bolp)
 282                  (> shr-indentation 0))
 283         (shr-indent))
 284       ;; No space is needed behind a wide character categorized as
 285       ;; kinsoku-bol, between characters both categorized as nospace,
 286       ;; or at the beginning of a line.
 287       (let (prev)
 288         (when (and (> (current-column) shr-indentation)
 289                    (eq (preceding-char) ? )
 290                    (or (= (line-beginning-position) (1- (point)))
 291                        (and (shr-char-breakable-p
 292                              (setq prev (char-after (- (point) 2))))
 293                             (shr-char-kinsoku-bol-p prev))
 294                        (and (shr-char-nospace-p prev)
 295                             (shr-char-nospace-p (aref elem 0)))))
 296           (delete-char -1)))
 297       ;; The shr-start is a special variable that is used to pass
 298       ;; upwards the first point in the buffer where the text really
 299       ;; starts.
 300       (unless shr-start
 301         (setq shr-start (point)))
 302       (insert elem)
 303       (let (found)
 304         (while (and (> (current-column) shr-width)
 305                     (progn
 306                       (setq found (shr-find-fill-point))
 307                       (not (eolp))))
 308           (when (eq (preceding-char) ? )
 309             (delete-char -1))
 310           (insert "\n")
 311           (unless found
 312             (put-text-property (1- (point)) (point) 'shr-break t)
 313             ;; No space is needed at the beginning of a line.
 314             (when (eq (following-char) ? )
 315               (delete-char 1)))
 316           (when (> shr-indentation 0)
 317             (shr-indent))
 318           (end-of-line))
 319         (insert " ")))
 320     (unless (string-match "[ \t\n]\\'" text)
 321       (delete-char -1)))))
 322
 323 (defun shr-find-fill-point ()
 324   (when (> (move-to-column shr-width) shr-width)
 325     (backward-char 1))
 326   (let ((bp (point))
 327         failed)
 328     (while (not (or (setq failed (= (current-column) shr-indentation))
 329                     (eq (preceding-char) ? )
 330                     (eq (following-char) ? )
 331                     (shr-char-breakable-p (preceding-char))
 332                     (shr-char-breakable-p (following-char))
 333                     (if (eq (preceding-char) ?')
 334                         (not (memq (char-after (- (point) 2))
 335                                    (list nil ?\n ? )))
 336                       (and (shr-char-kinsoku-bol-p (preceding-char))
 337                            (shr-char-breakable-p (following-char))
 338                            (not (shr-char-kinsoku-bol-p (following-char)))))
 339                     (shr-char-kinsoku-eol-p (following-char))))
 340       (backward-char 1))
 341     (if (and (not (or failed (eolp)))
 342              (eq (preceding-char) ?'))
 343         (while (not (or (setq failed (eolp))
 344                         (eq (following-char) ? )
 345                         (shr-char-breakable-p (following-char))
 346                         (shr-char-kinsoku-eol-p (following-char))))
 347           (forward-char 1)))
 348     (if failed
 349         ;; There's no breakable point, so we give it up.
 350         (let (found)
 351           (goto-char bp)
 352           (unless shr-kinsoku-shorten
 353             (while (and (setq found (re-search-forward
 354                                      "\\(\\c>\\)\\| \\|\\c<\\|\\c|"
 355                                      (line-end-position) 'move))
 356                         (eq (preceding-char) ?')))
 357             (if (and found (not (match-beginning 1)))
 358                 (goto-char (match-beginning 0)))))
 359       (or
 360        (eolp)
 361        ;; Don't put kinsoku-bol characters at the beginning of a line,
 362        ;; or kinsoku-eol characters at the end of a line.
 363        (cond
 364         (shr-kinsoku-shorten
 365          (while (and (not (memq (preceding-char) (list ?\C-@ ?\n ? )))
 366                      (shr-char-kinsoku-eol-p (preceding-char)))
 367            (backward-char 1))
 368          (when (setq failed (= (current-column) shr-indentation))
 369            ;; There's no breakable point that doesn't violate kinsoku,
 370            ;; so we look for the second best position.
 371            (while (and (progn
 372                          (forward-char 1)
 373                          (<= (current-column) shr-width))
 374                        (progn
 375                          (setq bp (point))
 376                          (shr-char-kinsoku-eol-p (following-char)))))
 377            (goto-char bp)))
 378         ((shr-char-kinsoku-eol-p (preceding-char))
 379          (if (shr-char-kinsoku-eol-p (following-char))
 380              ;; There are consecutive kinsoku-eol characters.
 381              (setq failed t)
 382            (let ((count 4))
 383              (while
 384                  (progn
 385                    (backward-char 1)
 386                    (and (> (setq count (1- count)) 0)
 387                         (not (memq (preceding-char) (list ?\C-@ ?\n ? )))
 388                         (or (shr-char-kinsoku-eol-p (preceding-char))
 389                             (shr-char-kinsoku-bol-p (following-char)))))))
 390            (if (setq failed (= (current-column) shr-indentation))
 391                ;; There's no breakable point that doesn't violate kinsoku,
 392                ;; so we go to the second best position.
 393                (if (looking-at "\\(\\c<+\\)\\c<")
 394                    (goto-char (match-end 1))
 395                  (forward-char 1)))))
 396         (t
 397          (if (shr-char-kinsoku-bol-p (preceding-char))
 398              ;; There are consecutive kinsoku-bol characters.
 399              (setq failed t)
 400            (let ((count 4))
 401              (while (and (>= (setq count (1- count)) 0)
 402                          (shr-char-kinsoku-bol-p (following-char))
 403                          (shr-char-breakable-p (following-char)))
 404                (forward-char 1))))))
 405        (when (eq (following-char) ? )
 406          (forward-char 1))))
 407     (not failed)))
 408
 409 (defun shr-expand-url (url)
 410   (cond
 411    ;; Absolute URL.
 412    ((or (not url)
 413         (string-match "\\`[a-z]*:" url)
 414         (not shr-base))
 415     url)
 416    ((and (not (string-match "/\\'" shr-base))
 417          (not (string-match "\\`/" url)))
 418     (concat shr-base "/" url))
 419    (t
 420     (concat shr-base url))))
 421
 422 (defun shr-ensure-newline ()
 423   (unless (zerop (current-column))
 424     (insert "\n")))
 425
 426 (defun shr-ensure-paragraph ()
 427   (unless (bobp)
 428     (if (<= (current-column) shr-indentation)
 429         (unless (save-excursion
 430                   (forward-line -1)
 431                   (looking-at " *$"))
 432           (insert "\n"))
 433       (if (save-excursion
 434             (beginning-of-line)
 435             (looking-at " *$"))
 436           (insert "\n")
 437         (insert "\n\n")))))
 438
 439 (defun shr-indent ()
 440   (when (> shr-indentation 0)
 441     (insert (make-string shr-indentation ? ))))
 442
 443 (defun shr-fontize-cont (cont &rest types)
 444   (let (shr-start)
 445     (shr-generic cont)
 446     (dolist (type types)
 447       (shr-add-font (or shr-start (point)) (point) type))))
 448
 449 ;; Add an overlay in the region, but avoid putting the font properties
 450 ;; on blank text at the start of the line, and the newline at the end,
 451 ;; to avoid ugliness.
 452 (defun shr-add-font (start end type)
 453   (save-excursion
 454     (goto-char start)
 455     (while (< (point) end)
 456       (when (bolp)
 457         (skip-chars-forward " "))
 458       (let ((overlay (make-overlay (point) (min (line-end-position) end))))
 459         (overlay-put overlay 'face type))
 460       (if (< (line-end-position) end)
 461           (forward-line 1)
 462         (goto-char end)))))
 463
 464 (defun shr-browse-url ()
 465   "Browse the URL under point."
 466   (interactive)
 467   (let ((url (get-text-property (point) 'shr-url)))
 468     (cond
 469      ((not url)
 470       (message "No link under point"))
 471      ((string-match "^mailto:" url)
 472       (browse-url-mailto url))
 473      (t
 474       (browse-url url)))))
 475
 476 (defun shr-save-contents (directory)
 477   "Save the contents from URL in a file."
 478   (interactive "DSave contents of URL to directory: ")
 479   (let ((url (get-text-property (point) 'shr-url)))
 480     (if (not url)
 481         (message "No link under point")
 482       (url-retrieve (shr-encode-url url)
 483                     'shr-store-contents (list url directory)))))
 484
 485 (defun shr-store-contents (status url directory)
 486   (unless (plist-get status :error)
 487     (when (or (search-forward "\n\n" nil t)
 488               (search-forward "\r\n\r\n" nil t))
 489       (write-region (point) (point-max)
 490                     (expand-file-name (file-name-nondirectory url)
 491                                       directory)))))
 492
 493 (defun shr-image-fetched (status buffer start end)
 494   (when (and (buffer-name buffer)
 495              (not (plist-get status :error)))
 496     (url-store-in-cache (current-buffer))
 497     (when (or (search-forward "\n\n" nil t)
 498               (search-forward "\r\n\r\n" nil t))
 499       (let ((data (buffer-substring (point) (point-max))))
 500         (with-current-buffer buffer
 501           (save-excursion
 502             (let ((alt (buffer-substring start end))
 503                   (inhibit-read-only t))
 504               (delete-region start end)
 505               (goto-char start)
 506               (funcall shr-put-image-function data alt)))))))
 507   (kill-buffer (current-buffer)))
 508
 509 (defun shr-put-image (data alt)
 510   "Put image DATA with a string ALT.  Return image."
 511   (if (display-graphic-p)
 512       (let ((image (ignore-errors
 513                      (shr-rescale-image data))))
 514         (when image
 515           ;; When inserting big-ish pictures, put them at the
 516           ;; beginning of the line.
 517           (when (and (> (current-column) 0)
 518                      (> (car (image-size image t)) 400))
 519             (insert "\n"))
 520           (insert-image image (or alt "*")))
 521         image)
 522     (insert alt)))
 523
 524 (defun shr-rescale-image (data)
 525   (if (or (not (fboundp 'imagemagick-types))
 526           (not (get-buffer-window (current-buffer))))
 527       (create-image data nil t)
 528     (let* ((image (create-image data nil t))
 529            (size (image-size image t))
 530            (width (car size))
 531            (height (cdr size))
 532            (edges (window-inside-pixel-edges
 533                    (get-buffer-window (current-buffer))))
 534            (window-width (truncate (* shr-max-image-proportion
 535                                       (- (nth 2 edges) (nth 0 edges)))))
 536            (window-height (truncate (* shr-max-image-proportion
 537                                        (- (nth 3 edges) (nth 1 edges)))))
 538            scaled-image)
 539       (when (> height window-height)
 540         (setq image (or (create-image data 'imagemagick t
 541                                       :height window-height)
 542                         image))
 543         (setq size (image-size image t)))
 544       (when (> (car size) window-width)
 545         (setq image (or
 546                      (create-image data 'imagemagick t
 547                                    :width window-width)
 548                      image)))
 549       (when (and (fboundp 'create-animated-image)
 550                  (eq (image-type data nil t) 'gif))
 551         (setq image (create-animated-image data 'gif t)))
 552       image)))
 553
 554 ;; url-cache-extract autoloads url-cache.
 555 (declare-function url-cache-create-filename "url-cache" (url))
 556 (autoload 'mm-disable-multibyte "mm-util")
 557 (autoload 'browse-url-mailto "browse-url")
 558
 559 (defun shr-get-image-data (url)
 560   "Get image data for URL.
 561 Return a string with image data."
 562   (with-temp-buffer
 563     (mm-disable-multibyte)
 564     (when (ignore-errors
 565             (url-cache-extract (url-cache-create-filename (shr-encode-url url)))
 566             t)
 567       (when (or (search-forward "\n\n" nil t)
 568                 (search-forward "\r\n\r\n" nil t))
 569         (buffer-substring (point) (point-max))))))
 570
 571 (defun shr-image-displayer (content-function)
 572   "Return a function to display an image.
 573 CONTENT-FUNCTION is a function to retrieve an image for a cid url that
 574 is an argument.  The function to be returned takes three arguments URL,
 575 START, and END.  Note that START and END should be merkers."
 576   `(lambda (url start end)
 577      (when url
 578        (if (string-match "\\`cid:" url)
 579            ,(when content-function
 580               `(let ((image (funcall ,content-function
 581                                      (substring url (match-end 0)))))
 582                  (when image
 583                    (goto-char start)
 584                    (funcall shr-put-image-function
 585                             image (buffer-substring start end))
 586                    (delete-region (point) end))))
 587          (url-retrieve url 'shr-image-fetched
 588                        (list (current-buffer) start end)
 589                        t)))))
 590
 591 (defun shr-heading (cont &rest types)
 592   (shr-ensure-paragraph)
 593   (apply #'shr-fontize-cont cont types)
 594   (shr-ensure-paragraph))
 595
 596 (autoload 'widget-convert-button "wid-edit")
 597
 598 (defun shr-urlify (start url &optional title)
 599   (widget-convert-button
 600    'url-link start (point)
 601    :help-echo (if title (format "%s (%s)" url title) url)
 602    :keymap shr-map
 603    url)
 604   (put-text-property start (point) 'face 'shr-link)
 605   (put-text-property start (point) 'shr-url url))
 606
 607 (defun shr-encode-url (url)
 608   "Encode URL."
 609   (browse-url-url-encode-chars url "[)$ ]"))
 610
 611 (autoload 'shr-color-visible "shr-color")
 612 (autoload 'shr-color->hexadecimal "shr-color")
 613
 614 (defun shr-color-check (fg bg)
 615   "Check that FG is visible on BG.
 616 Returns (fg bg) with corrected values.
 617 Returns nil if the colors that would be used are the default
 618 ones, in case fg and bg are nil."
 619   (when (or fg bg)
 620     (let ((fixed (cond ((null fg) 'fg)
 621                        ((null bg) 'bg))))
 622       ;; Convert colors to hexadecimal, or set them to default.
 623       (let ((fg (or (shr-color->hexadecimal fg)
 624                     (frame-parameter nil 'foreground-color)))
 625             (bg (or (shr-color->hexadecimal bg)
 626                     (frame-parameter nil 'background-color))))
 627         (cond ((eq fixed 'bg)
 628                ;; Only return the new fg
 629                (list nil (cadr (shr-color-visible bg fg t))))
 630               ((eq fixed 'fg)
 631                ;; Invert args and results and return only the new bg
 632                (list (cadr (shr-color-visible fg bg t)) nil))
 633               (t
 634                (shr-color-visible bg fg)))))))
 635
 636 (defun shr-colorize-region (start end fg &optional bg)
 637   (when (or fg bg)
 638     (let ((new-colors (shr-color-check fg bg)))
 639       (when new-colors
 640         (when fg
 641           (shr-put-color start end :foreground (cadr new-colors)))
 642         (when bg
 643           (shr-put-color start end :background (car new-colors))))
 644       new-colors)))
 645
 646 ;; Put a color in the region, but avoid putting colors on blank
 647 ;; text at the start of the line, and the newline at the end, to avoid
 648 ;; ugliness.  Also, don't overwrite any existing color information,
 649 ;; since this can be called recursively, and we want the "inner" color
 650 ;; to win.
 651 (defun shr-put-color (start end type color)
 652   (save-excursion
 653     (goto-char start)
 654     (while (< (point) end)
 655       (when (and (bolp)
 656                  (not (eq type :background)))
 657         (skip-chars-forward " "))
 658       (when (> (line-end-position) (point))
 659         (shr-put-color-1 (point) (min (line-end-position) end) type color))
 660       (if (< (line-end-position) end)
 661           (forward-line 1)
 662         (goto-char end)))
 663     (when (and (eq type :background)
 664                (= shr-table-depth 0))
 665       (shr-expand-newlines start end color))))
 666
 667 (defun shr-expand-newlines (start end color)
 668   (save-restriction
 669     ;; Skip past all white space at the start and ends.
 670     (goto-char start)
 671     (skip-chars-forward " \t\n")
 672     (beginning-of-line)
 673     (setq start (point))
 674     (goto-char end)
 675     (skip-chars-backward " \t\n")
 676     (forward-line 1)
 677     (setq end (point))
 678     (narrow-to-region start end)
 679     (let ((width (shr-natural-width))
 680           column)
 681       (goto-char (point-min))
 682       (while (not (eobp))
 683         (end-of-line)
 684         (when (and (< (setq column (current-column)) width)
 685                    (< (setq column (shr-previous-newline-padding-width column))
 686                       width))
 687           (let ((overlay (make-overlay (point) (1+ (point)))))
 688             (overlay-put overlay 'before-string
 689                          (concat
 690                           (mapconcat
 691                            (lambda (overlay)
 692                              (let ((string (plist-get
 693                                             (overlay-properties overlay)
 694                                             'before-string)))
 695                                (if (not string)
 696                                    ""
 697                                  (overlay-put overlay 'before-string "")
 698                                  string)))
 699                            (overlays-at (point))
 700                            "")
 701                           (propertize (make-string (- width column) ? )
 702                                       'face (list :background color))))))
 703         (forward-line 1)))))
 704
 705 (defun shr-previous-newline-padding-width (width)
 706   (let ((overlays (overlays-at (point)))
 707         (previous-width 0))
 708     (if (null overlays)
 709         width
 710       (dolist (overlay overlays)
 711         (setq previous-width
 712               (+ previous-width
 713                  (length (plist-get (overlay-properties overlay)
 714                                     'before-string)))))
 715       (+ width previous-width))))
 716
 717 (defun shr-put-color-1 (start end type color)
 718   (let* ((old-props (get-text-property start 'face))
 719          (do-put (and (listp old-props)
 720                       (not (memq type old-props))))
 721          change)
 722     (while (< start end)
 723       (setq change (next-single-property-change start 'face nil end))
 724       (when do-put
 725         (put-text-property start change 'face
 726                            (nconc (list type color) old-props)))
 727       (setq old-props (get-text-property change 'face))
 728       (setq do-put (and (listp old-props)
 729                         (not (memq type old-props))))
 730       (setq start change))
 731     (when (and do-put
 732                (> end start))
 733       (put-text-property start end 'face
 734                          (nconc (list type color old-props))))))
 735
 736 ;;; Tag-specific rendering rules.
 737
 738 (defun shr-tag-body (cont)
 739   (let* ((start (point))
 740          (fgcolor (cdr (or (assq :fgcolor cont)
 741                            (assq :text cont))))
 742          (bgcolor (cdr (assq :bgcolor cont)))
 743          (shr-stylesheet (list (cons 'color fgcolor)
 744                                (cons 'background-color bgcolor))))
 745     (shr-generic cont)
 746     (shr-colorize-region start (point) fgcolor bgcolor)))
 747
 748 (defun shr-tag-style (cont)
 749   )
 750
 751 (defun shr-tag-script (cont)
 752   )
 753
 754 (defun shr-tag-sup (cont)
 755   (let ((start (point)))
 756     (shr-generic cont)
 757     (put-text-property start (point) 'display '(raise 0.5))))
 758
 759 (defun shr-tag-sub (cont)
 760   (let ((start (point)))
 761     (shr-generic cont)
 762     (put-text-property start (point) 'display '(raise -0.5))))
 763
 764 (defun shr-tag-label (cont)
 765   (shr-generic cont)
 766   (shr-ensure-paragraph))
 767
 768 (defun shr-tag-p (cont)
 769   (shr-ensure-paragraph)
 770   (shr-indent)
 771   (shr-generic cont)
 772   (shr-ensure-paragraph))
 773
 774 (defun shr-tag-div (cont)
 775   (shr-ensure-newline)
 776   (shr-indent)
 777   (shr-generic cont)
 778   (shr-ensure-newline))
 779
 780 (defun shr-tag-s (cont)
 781   (shr-fontize-cont cont 'shr-strike-through))
 782
 783 (defun shr-tag-del (cont)
 784   (shr-fontize-cont cont 'shr-strike-through))
 785
 786 (defun shr-tag-b (cont)
 787   (shr-fontize-cont cont 'bold))
 788
 789 (defun shr-tag-i (cont)
 790   (shr-fontize-cont cont 'italic))
 791
 792 (defun shr-tag-em (cont)
 793   (shr-fontize-cont cont 'bold))
 794
 795 (defun shr-tag-strong (cont)
 796   (shr-fontize-cont cont 'bold))
 797
 798 (defun shr-tag-u (cont)
 799   (shr-fontize-cont cont 'underline))
 800
 801 (defun shr-parse-style (style)
 802   (when style
 803     (save-match-data
 804       (when (string-match "\n" style)
 805         (setq style (replace-match " " t t style))))
 806     (let ((plist nil))
 807       (dolist (elem (split-string style ";"))
 808         (when elem
 809           (setq elem (split-string elem ":"))
 810           (when (and (car elem)
 811                      (cadr elem))
 812             (let ((name (replace-regexp-in-string "^ +\\| +$" "" (car elem)))
 813                   (value (replace-regexp-in-string "^ +\\| +$" "" (cadr elem))))
 814               (when (string-match " *!important\\'" value)
 815                 (setq value (substring value 0 (match-beginning 0))))
 816               (push (cons (intern name obarray)
 817                           value)
 818                     plist)))))
 819       plist)))
 820
 821 (defun shr-tag-base (cont)
 822   (setq shr-base (cdr (assq :href cont))))
 823
 824 (defun shr-tag-a (cont)
 825   (let ((url (cdr (assq :href cont)))
 826         (title (cdr (assq :title cont)))
 827         (start (point))
 828         shr-start)
 829     (shr-generic cont)
 830     (shr-urlify (or shr-start start) (shr-expand-url url) title)))
 831
 832 (defun shr-tag-object (cont)
 833   (let ((start (point))
 834         url)
 835     (dolist (elem cont)
 836       (when (eq (car elem) 'embed)
 837         (setq url (or url (cdr (assq :src (cdr elem))))))
 838       (when (and (eq (car elem) 'param)
 839                  (equal (cdr (assq :name (cdr elem))) "movie"))
 840         (setq url (or url (cdr (assq :value (cdr elem)))))))
 841     (when url
 842       (shr-insert " [multimedia] ")
 843       (shr-urlify start (shr-expand-url url)))
 844     (shr-generic cont)))
 845
 846 (defun shr-tag-video (cont)
 847   (let ((image (cdr (assq :poster cont)))
 848         (url (cdr (assq :src cont)))
 849         (start (point)))
 850     (shr-tag-img nil image)
 851     (shr-urlify start (shr-expand-url url))))
 852
 853 (defun shr-tag-img (cont &optional url)
 854   (when (or url
 855             (and cont
 856                  (cdr (assq :src cont))))
 857     (when (and (> (current-column) 0)
 858                (not (eq shr-state 'image)))
 859       (insert "\n"))
 860     (let ((alt (cdr (assq :alt cont)))
 861           (url (shr-expand-url (or url (cdr (assq :src cont))))))
 862       (let ((start (point-marker)))
 863         (when (zerop (length alt))
 864           (setq alt "*"))
 865         (cond
 866          ((or (member (cdr (assq :height cont)) '("0" "1"))
 867               (member (cdr (assq :width cont)) '("0" "1")))
 868           ;; Ignore zero-sized or single-pixel images.
 869           )
 870          ((and (not shr-inhibit-images)
 871                (string-match "\\`cid:" url))
 872           (let ((url (substring url (match-end 0)))
 873                 image)
 874             (if (or (not shr-content-function)
 875                     (not (setq image (funcall shr-content-function url))))
 876                 (insert alt)
 877               (funcall shr-put-image-function image alt))))
 878          ((or shr-inhibit-images
 879               (and shr-blocked-images
 880                    (string-match shr-blocked-images url)))
 881           (setq shr-start (point))
 882           (let ((shr-state 'space))
 883             (if (> (string-width alt) 8)
 884                 (shr-insert (truncate-string-to-width alt 8))
 885               (shr-insert alt))))
 886          ((url-is-cached (shr-encode-url url))
 887           (funcall shr-put-image-function (shr-get-image-data url) alt))
 888          (t
 889           (insert alt)
 890           (funcall
 891            (if (fboundp 'url-queue-retrieve)
 892                'url-queue-retrieve
 893              'url-retrieve)
 894            (shr-encode-url url) 'shr-image-fetched
 895            (list (current-buffer) start (point-marker))
 896            t)))
 897         (put-text-property start (point) 'keymap shr-map)
 898         (put-text-property start (point) 'shr-alt alt)
 899         (put-text-property start (point) 'image-url url)
 900         (put-text-property start (point) 'image-displayer
 901                            (shr-image-displayer shr-content-function))
 902         (put-text-property start (point) 'help-echo alt)
 903         (setq shr-state 'image)))))
 904
 905 (defun shr-tag-pre (cont)
 906   (let ((shr-folding-mode 'none))
 907     (shr-ensure-newline)
 908     (shr-indent)
 909     (shr-generic cont)
 910     (shr-ensure-newline)))
 911
 912 (defun shr-tag-blockquote (cont)
 913   (shr-ensure-paragraph)
 914   (shr-indent)
 915   (let ((shr-indentation (+ shr-indentation 4)))
 916     (shr-generic cont))
 917   (shr-ensure-paragraph))
 918
 919 (defun shr-tag-ul (cont)
 920   (shr-ensure-paragraph)
 921   (let ((shr-list-mode 'ul))
 922     (shr-generic cont))
 923   (shr-ensure-paragraph))
 924
 925 (defun shr-tag-ol (cont)
 926   (shr-ensure-paragraph)
 927   (let ((shr-list-mode 1))
 928     (shr-generic cont))
 929   (shr-ensure-paragraph))
 930
 931 (defun shr-tag-li (cont)
 932   (shr-ensure-paragraph)
 933   (shr-indent)
 934   (let* ((bullet
 935           (if (numberp shr-list-mode)
 936               (prog1
 937                   (format "%d " shr-list-mode)
 938                 (setq shr-list-mode (1+ shr-list-mode)))
 939             "* "))
 940          (shr-indentation (+ shr-indentation (length bullet))))
 941     (insert bullet)
 942     (shr-generic cont)))
 943
 944 (defun shr-tag-br (cont)
 945   (unless (bobp)
 946     (insert "\n")
 947     (shr-indent))
 948   (shr-generic cont))
 949
 950 (defun shr-tag-h1 (cont)
 951   (shr-heading cont 'bold 'underline))
 952
 953 (defun shr-tag-h2 (cont)
 954   (shr-heading cont 'bold))
 955
 956 (defun shr-tag-h3 (cont)
 957   (shr-heading cont 'italic))
 958
 959 (defun shr-tag-h4 (cont)
 960   (shr-heading cont))
 961
 962 (defun shr-tag-h5 (cont)
 963   (shr-heading cont))
 964
 965 (defun shr-tag-h6 (cont)
 966   (shr-heading cont))
 967
 968 (defun shr-tag-hr (cont)
 969   (shr-ensure-newline)
 970   (insert (make-string shr-width shr-hr-line) "\n"))
 971
 972 (defun shr-tag-title (cont)
 973   (shr-heading cont 'bold 'underline))
 974
 975 (defun shr-tag-font (cont)
 976   (let* ((start (point))
 977          (color (cdr (assq :color cont)))
 978          (shr-stylesheet (nconc (list (cons 'color color))
 979                                 shr-stylesheet)))
 980     (shr-generic cont)
 981     (when color
 982       (shr-colorize-region start (point) color
 983                            (cdr (assq 'background-color shr-stylesheet))))))
 984
 985 ;;; Table rendering algorithm.
 986
 987 ;; Table rendering is the only complicated thing here.  We do this by
 988 ;; first counting how many TDs there are in each TR, and registering
 989 ;; how wide they think they should be ("width=45%", etc).  Then we
 990 ;; render each TD separately (this is done in temporary buffers, so
 991 ;; that we can use all the rendering machinery as if we were in the
 992 ;; main buffer).  Now we know how much space each TD really takes, so
 993 ;; we then render everything again with the new widths, and finally
 994 ;; insert all these boxes into the main buffer.
 995 (defun shr-tag-table-1 (cont)
 996   (setq cont (or (cdr (assq 'tbody cont))
 997                  cont))
 998   (let* ((shr-inhibit-images t)
 999          (shr-table-depth (1+ shr-table-depth))
1000          (shr-kinsoku-shorten t)
1001          ;; Find all suggested widths.
1002          (columns (shr-column-specs cont))
1003          ;; Compute how many characters wide each TD should be.
1004          (suggested-widths (shr-pro-rate-columns columns))
1005          ;; Do a "test rendering" to see how big each TD is (this can
1006          ;; be smaller (if there's little text) or bigger (if there's
1007          ;; unbreakable text).
1008          (sketch (shr-make-table cont suggested-widths))
1009          (sketch-widths (shr-table-widths sketch suggested-widths)))
1010     ;; This probably won't work very well.
1011     (when (> (+ (loop for width across sketch-widths
1012                       summing (1+ width))
1013                 shr-indentation 1)
1014              (frame-width))
1015       (setq truncate-lines t))
1016     ;; Then render the table again with these new "hard" widths.
1017     (shr-insert-table (shr-make-table cont sketch-widths t) sketch-widths))
1018   ;; Finally, insert all the images after the table.  The Emacs buffer
1019   ;; model isn't strong enough to allow us to put the images actually
1020   ;; into the tables.
1021   (when (zerop shr-table-depth)
1022     (dolist (elem (shr-find-elements cont 'img))
1023       (shr-tag-img (cdr elem)))))
1024
1025 (defun shr-tag-table (cont)
1026   (shr-ensure-paragraph)
1027   (let* ((caption (cdr (assq 'caption cont)))
1028          (header (cdr (assq 'thead cont)))
1029          (body (or (cdr (assq 'tbody cont)) cont))
1030          (footer (cdr (assq 'tfoot cont)))
1031          (bgcolor (cdr (assq :bgcolor cont)))
1032          (start (point))
1033          (shr-stylesheet (nconc (list (cons 'background-color bgcolor))
1034                                 shr-stylesheet))
1035          (nheader (if header (shr-max-columns header)))
1036          (nbody (if body (shr-max-columns body)))
1037          (nfooter (if footer (shr-max-columns footer))))
1038     (shr-tag-table-1
1039      (nconc
1040       (if caption `((tr (td ,@caption))))
1041       (if header
1042           (if footer
1043               ;; hader + body + footer
1044               (if (= nheader nbody)
1045                   (if (= nbody nfooter)
1046                       `((tr (td (table (tbody ,@header ,@body ,@footer)))))
1047                     (nconc `((tr (td (table (tbody ,@header ,@body)))))
1048                            (if (= nfooter 1)
1049                                footer
1050                              `((tr (td (table (tbody ,@footer))))))))
1051                 (nconc `((tr (td (table (tbody ,@header)))))
1052                        (if (= nbody nfooter)
1053                            `((tr (td (table (tbody ,@body ,@footer)))))
1054                          (nconc `((tr (td (table (tbody ,@body)))))
1055                                 (if (= nfooter 1)
1056                                     footer
1057                                   `((tr (td (table (tbody ,@footer))))))))))
1058             ;; header + body
1059             (if (= nheader nbody)
1060                 `((tr (td (table (tbody ,@header ,@body)))))
1061               (if (= nheader 1)
1062                   `(,@header (tr (td (table (tbody ,@body)))))
1063                 `((tr (td (table (tbody ,@header))))
1064                   (tr (td (table (tbody ,@body))))))))
1065         (if footer
1066             ;; body + footer
1067             (if (= nbody nfooter)
1068                 `((tr (td (table (tbody ,@body ,@footer)))))
1069               (nconc `((tr (td (table (tbody ,@body)))))
1070                      (if (= nfooter 1)
1071                          footer
1072                        `((tr (td (table (tbody ,@footer))))))))
1073           (if caption
1074               `((tr (td (table (tbody ,@body)))))
1075             body)))))
1076     (when bgcolor
1077       (shr-colorize-region start (point) (cdr (assq 'color shr-stylesheet))
1078                            bgcolor))))
1079
1080 (defun shr-find-elements (cont type)
1081   (let (result)
1082     (dolist (elem cont)
1083       (cond ((eq (car elem) type)
1084              (push elem result))
1085             ((consp (cdr elem))
1086              (setq result (nconc (shr-find-elements (cdr elem) type) result)))))
1087     (nreverse result)))
1088
1089 (defun shr-insert-table (table widths)
1090   (shr-insert-table-ruler widths)
1091   (dolist (row table)
1092     (let ((start (point))
1093           (height (let ((max 0))
1094                     (dolist (column row)
1095                       (setq max (max max (cadr column))))
1096                     max)))
1097       (dotimes (i height)
1098         (shr-indent)
1099         (insert shr-table-vertical-line "\n"))
1100       (dolist (column row)
1101         (goto-char start)
1102         (let ((lines (nth 2 column))
1103               (overlay-lines (nth 3 column))
1104               overlay overlay-line)
1105           (dolist (line lines)
1106             (setq overlay-line (pop overlay-lines))
1107             (end-of-line)
1108             (insert line shr-table-vertical-line)
1109             (dolist (overlay overlay-line)
1110               (let ((o (make-overlay (- (point) (nth 0 overlay) 1)
1111                                      (- (point) (nth 1 overlay) 1)))
1112                     (properties (nth 2 overlay)))
1113                 (while properties
1114                   (overlay-put o (pop properties) (pop properties)))))
1115             (forward-line 1))
1116           ;; Add blank lines at padding at the bottom of the TD,
1117           ;; possibly.
1118           (dotimes (i (- height (length lines)))
1119             (end-of-line)
1120             (let ((start (point)))
1121               (insert (make-string (string-width (car lines)) ? )
1122                       shr-table-vertical-line)
1123               (when (nth 4 column)
1124                 (shr-put-color start (1- (point)) :background (nth 4 column))))
1125             (forward-line 1)))))
1126     (shr-insert-table-ruler widths)))
1127
1128 (defun shr-insert-table-ruler (widths)
1129   (when (and (bolp)
1130              (> shr-indentation 0))
1131     (shr-indent))
1132   (insert shr-table-corner)
1133   (dotimes (i (length widths))
1134     (insert (make-string (aref widths i) shr-table-horizontal-line)
1135             shr-table-corner))
1136   (insert "\n"))
1137
1138 (defun shr-table-widths (table suggested-widths)
1139   (let* ((length (length suggested-widths))
1140          (widths (make-vector length 0))
1141          (natural-widths (make-vector length 0)))
1142     (dolist (row table)
1143       (let ((i 0))
1144         (dolist (column row)
1145           (aset widths i (max (aref widths i)
1146                               (car column)))
1147           (aset natural-widths i (max (aref natural-widths i)
1148                                       (cadr column)))
1149           (setq i (1+ i)))))
1150     (let ((extra (- (apply '+ (append suggested-widths nil))
1151                     (apply '+ (append widths nil))))
1152           (expanded-columns 0))
1153       (when (> extra 0)
1154         (dotimes (i length)
1155           ;; If the natural width is wider than the rendered width, we
1156           ;; want to allow the column to expand.
1157           (when (> (aref natural-widths i) (aref widths i))
1158             (setq expanded-columns (1+ expanded-columns))))
1159         (dotimes (i length)
1160           (when (> (aref natural-widths i) (aref widths i))
1161             (aset widths i (min
1162                             (1+ (aref natural-widths i))
1163                             (+ (/ extra expanded-columns)
1164                                (aref widths i))))))))
1165     widths))
1166
1167 (defun shr-make-table (cont widths &optional fill)
1168   (let ((trs nil))
1169     (dolist (row cont)
1170       (when (eq (car row) 'tr)
1171         (let ((tds nil)
1172               (columns (cdr row))
1173               (i 0)
1174               column)
1175           (while (< i (length widths))
1176             (setq column (pop columns))
1177             (when (or (memq (car column) '(td th))
1178                       (null column))
1179               (push (shr-render-td (cdr column) (aref widths i) fill)
1180                     tds)
1181               (setq i (1+ i))))
1182           (push (nreverse tds) trs))))
1183     (nreverse trs)))
1184
1185 (defun shr-render-td (cont width fill)
1186   (with-temp-buffer
1187     (let ((bgcolor (cdr (assq :bgcolor cont)))
1188           (fgcolor (cdr (assq :fgcolor cont)))
1189           (style (cdr (assq :style cont)))
1190           (shr-stylesheet shr-stylesheet)
1191           overlays actual-colors)
1192       (when style
1193         (setq style (and (string-match "color" style)
1194                          (shr-parse-style style))))
1195       (when bgcolor
1196         (setq style (nconc (list (cons 'background-color bgcolor)) style)))
1197       (when fgcolor
1198         (setq style (nconc (list (cons 'color fgcolor)) style)))
1199       (when style
1200         (setq shr-stylesheet (append style shr-stylesheet)))
1201       (let ((cache (cdr (assoc (cons width cont) shr-content-cache))))
1202         (if cache
1203             (progn
1204               (insert (car cache))
1205               (let ((end (length (car cache))))
1206                 (dolist (overlay (cadr cache))
1207                   (let ((new-overlay
1208                          (make-overlay (1+ (- end (nth 0 overlay)))
1209                                        (1+ (- end (nth 1 overlay)))))
1210                         (properties (nth 2 overlay)))
1211                     (while properties
1212                       (overlay-put new-overlay
1213                                    (pop properties) (pop properties)))))))
1214           (let ((shr-width width)
1215                 (shr-indentation 0))
1216             (shr-descend (cons 'td cont)))
1217           (delete-region
1218            (point)
1219            (+ (point)
1220               (skip-chars-backward " \t\n")))
1221           (push (list (cons width cont) (buffer-string)
1222                       (shr-overlays-in-region (point-min) (point-max)))
1223                 shr-content-cache)))
1224       (goto-char (point-min))
1225       (let ((max 0))
1226         (while (not (eobp))
1227           (end-of-line)
1228           (setq max (max max (current-column)))
1229           (forward-line 1))
1230         (when fill
1231           (goto-char (point-min))
1232           ;; If the buffer is totally empty, then put a single blank
1233           ;; line here.
1234           (if (zerop (buffer-size))
1235               (insert (make-string width ? ))
1236             ;; Otherwise, fill the buffer.
1237             (while (not (eobp))
1238               (end-of-line)
1239               (when (> (- width (current-column)) 0)
1240                 (insert (make-string (- width (current-column)) ? )))
1241               (forward-line 1)))
1242           (when style
1243             (setq actual-colors
1244                   (shr-colorize-region
1245                    (point-min) (point-max)
1246                    (cdr (assq 'color shr-stylesheet))
1247                    (cdr (assq 'background-color shr-stylesheet))))))
1248         (if fill
1249             (list max
1250                   (count-lines (point-min) (point-max))
1251                   (split-string (buffer-string) "\n")
1252                   (shr-collect-overlays)
1253                   (car actual-colors))
1254           (list max
1255                 (shr-natural-width)))))))
1256
1257 (defun shr-natural-width ()
1258   (goto-char (point-min))
1259   (let ((current 0)
1260         (max 0))
1261     (while (not (eobp))
1262       (end-of-line)
1263       (setq current (+ current (current-column)))
1264       (unless (get-text-property (point) 'shr-break)
1265         (setq max (max max current)
1266               current 0))
1267       (forward-line 1))
1268     max))
1269
1270 (defun shr-collect-overlays ()
1271   (save-excursion
1272     (goto-char (point-min))
1273     (let ((overlays nil))
1274       (while (not (eobp))
1275         (push (shr-overlays-in-region (point) (line-end-position))
1276               overlays)
1277         (forward-line 1))
1278       (nreverse overlays))))
1279
1280 (defun shr-overlays-in-region (start end)
1281   (let (result)
1282     (dolist (overlay (overlays-in start end))
1283       (push (list (if (> start (overlay-start overlay))
1284                       (- end start)
1285                     (- end (overlay-start overlay)))
1286                   (if (< end (overlay-end overlay))
1287                       0
1288                     (- end (overlay-end overlay)))
1289                   (overlay-properties overlay))
1290             result))
1291     (nreverse result)))
1292
1293 (defun shr-pro-rate-columns (columns)
1294   (let ((total-percentage 0)
1295         (widths (make-vector (length columns) 0)))
1296     (dotimes (i (length columns))
1297       (setq total-percentage (+ total-percentage (aref columns i))))
1298     (setq total-percentage (/ 1.0 total-percentage))
1299     (dotimes (i (length columns))
1300       (aset widths i (max (truncate (* (aref columns i)
1301                                        total-percentage
1302                                        (- shr-width (1+ (length columns)))))
1303                           10)))
1304     widths))
1305
1306 ;; Return a summary of the number and shape of the TDs in the table.
1307 (defun shr-column-specs (cont)
1308   (let ((columns (make-vector (shr-max-columns cont) 1)))
1309     (dolist (row cont)
1310       (when (eq (car row) 'tr)
1311         (let ((i 0))
1312           (dolist (column (cdr row))
1313             (when (memq (car column) '(td th))
1314               (let ((width (cdr (assq :width (cdr column)))))
1315                 (when (and width
1316                            (string-match "\\([0-9]+\\)%" width))
1317                   (aset columns i
1318                         (/ (string-to-number (match-string 1 width))
1319                            100.0))))
1320               (setq i (1+ i)))))))
1321     columns))
1322
1323 (defun shr-count (cont elem)
1324   (let ((i 0))
1325     (dolist (sub cont)
1326       (when (eq (car sub) elem)
1327         (setq i (1+ i))))
1328     i))
1329
1330 (defun shr-max-columns (cont)
1331   (let ((max 0))
1332     (dolist (row cont)
1333       (when (eq (car row) 'tr)
1334         (setq max (max max (+ (shr-count (cdr row) 'td)
1335                               (shr-count (cdr row) 'th))))))
1336     max))
1337
1338 (provide 'shr)
1339
1340 ;;; shr.el ends here