;;; shr.el --- Simple HTML Renderer
-;; Copyright (C) 2010 Free Software Foundation, Inc.
+;; Copyright (C) 2010, 2011 Free Software Foundation, Inc.
;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
;; Keywords: html
(eval-when-compile (require 'cl))
(require 'browse-url)
-(unless (aref (char-category-set (make-char 'japanese-jisx0208 33 35)) ?>)
- (load "kinsoku" nil t))
(defgroup shr nil
"Simple HTML Renderer"
:group 'shr
:type 'regexp)
-(defcustom shr-table-line ?-
- "Character used to draw table line."
+(defcustom shr-table-horizontal-line ?-
+ "Character used to draw horizontal table lines."
+ :group 'shr
+ :type 'character)
+
+(defcustom shr-table-vertical-line ?|
+ "Character used to draw vertical table lines."
:group 'shr
:type 'character)
(defcustom shr-table-corner ?+
- "Character used to draw table corner."
+ "Character used to draw table corners."
:group 'shr
:type 'character)
(defcustom shr-hr-line ?-
- "Character used to draw hr line."
+ "Character used to draw hr lines."
:group 'shr
:type 'character)
(defcustom shr-width fill-column
- "Frame width to use for rendering."
- :type 'integer
+ "Frame width to use for rendering.
+May either be an integer specifying a fixed width in characters,
+or nil, meaning that the full width of the window should be
+used."
+ :type '(choice (integer :tag "Fixed width in characters")
+ (const :tag "Use the width of the window" nil))
:group 'shr)
(defvar shr-content-function nil
(defvar shr-content-cache nil)
(defvar shr-kinsoku-shorten nil)
(defvar shr-table-depth 0)
+(defvar shr-stylesheet nil)
(defvar shr-map
(let ((map (make-sparse-keymap)))
(defun shr-insert-document (dom)
(setq shr-content-cache nil)
(let ((shr-state nil)
- (shr-start nil))
+ (shr-start nil)
+ (shr-width (or shr-width (window-width))))
(shr-descend (shr-transform-dom dom))))
(defun shr-copy-url ()
(nreverse result)))
(defun shr-descend (dom)
- (let ((function (intern (concat "shr-tag-" (symbol-name (car dom))) obarray)))
+ (let ((function (intern (concat "shr-tag-" (symbol-name (car dom))) obarray))
+ (style (cdr (assq :style (cdr dom))))
+ (shr-stylesheet shr-stylesheet)
+ (start (point)))
+ (when style
+ (if (string-match "color" style)
+ (setq shr-stylesheet (nconc (shr-parse-style style)
+ shr-stylesheet))
+ (setq style nil)))
(if (fboundp function)
(funcall function (cdr dom))
- (shr-generic (cdr dom)))))
+ (shr-generic (cdr dom)))
+ ;; If style is set, then this node has set the color.
+ (when style
+ (shr-colorize-region start (point)
+ (cdr (assq 'color shr-stylesheet))
+ (cdr (assq 'background-color shr-stylesheet))))))
(defun shr-generic (cont)
(dolist (sub cont)
((listp (cdr sub))
(shr-descend sub)))))
+(defmacro shr-char-breakable-p (char)
+ "Return non-nil if a line can be broken before and after CHAR."
+ `(aref fill-find-break-point-function-table ,char))
+(defmacro shr-char-nospace-p (char)
+ "Return non-nil if no space is required before and after CHAR."
+ `(aref fill-nospace-between-words-table ,char))
+
+;; KINSOKU is a Japanese word meaning a rule that should not be violated.
+;; In Emacs, it is a term used for characters, e.g. punctuation marks,
+;; parentheses, and so on, that should not be placed in the beginning
+;; of a line or the end of a line.
+(defmacro shr-char-kinsoku-bol-p (char)
+ "Return non-nil if a line ought not to begin with CHAR."
+ `(aref (char-category-set ,char) ?>))
+(defmacro shr-char-kinsoku-eol-p (char)
+ "Return non-nil if a line ought not to end with CHAR."
+ `(aref (char-category-set ,char) ?<))
+(unless (shr-char-kinsoku-bol-p (make-char 'japanese-jisx0208 33 35))
+ (load "kinsoku" nil t))
+
(defun shr-insert (text)
(when (and (eq shr-state 'image)
(not (string-match "\\`[ \t\n]+\\'" text)))
(when (and (bolp)
(> shr-indentation 0))
(shr-indent))
- ;; The shr-start is a special variable that is used to pass
- ;; upwards the first point in the buffer where the text really
- ;; starts.
- (unless shr-start
- (setq shr-start (point)))
;; No space is needed behind a wide character categorized as
;; kinsoku-bol, between characters both categorized as nospace,
;; or at the beginning of a line.
(let (prev)
- (when (and (eq (preceding-char) ? )
+ (when (and (> (current-column) shr-indentation)
+ (eq (preceding-char) ? )
(or (= (line-beginning-position) (1- (point)))
- (and (aref fill-find-break-point-function-table
- (setq prev (char-after (- (point) 2))))
- (aref (char-category-set prev) ?>))
- (and (aref fill-nospace-between-words-table prev)
- (aref fill-nospace-between-words-table
- (aref elem 0)))))
+ (and (shr-char-breakable-p
+ (setq prev (char-after (- (point) 2))))
+ (shr-char-kinsoku-bol-p prev))
+ (and (shr-char-nospace-p prev)
+ (shr-char-nospace-p (aref elem 0)))))
(delete-char -1)))
+ ;; The shr-start is a special variable that is used to pass
+ ;; upwards the first point in the buffer where the text really
+ ;; starts.
+ (unless shr-start
+ (setq shr-start (point)))
(insert elem)
(let (found)
(while (and (> (current-column) shr-width)
(defun shr-find-fill-point ()
(when (> (move-to-column shr-width) shr-width)
(backward-char 1))
- (let (failed)
- (while (not
- (or (setq failed (= (current-column) shr-indentation))
- (eq (preceding-char) ? )
- (eq (following-char) ? )
- (aref fill-find-break-point-function-table (preceding-char))))
+ (let ((bp (point))
+ failed)
+ (while (not (or (setq failed (= (current-column) shr-indentation))
+ (eq (preceding-char) ? )
+ (eq (following-char) ? )
+ (shr-char-breakable-p (preceding-char))
+ (shr-char-breakable-p (following-char))
+ (if (eq (preceding-char) ?')
+ (not (memq (char-after (- (point) 2))
+ (list nil ?\n ? )))
+ (and (shr-char-kinsoku-bol-p (preceding-char))
+ (shr-char-breakable-p (following-char))
+ (not (shr-char-kinsoku-bol-p (following-char)))))
+ (shr-char-kinsoku-eol-p (following-char))))
(backward-char 1))
+ (if (and (not (or failed (eolp)))
+ (eq (preceding-char) ?'))
+ (while (not (or (setq failed (eolp))
+ (eq (following-char) ? )
+ (shr-char-breakable-p (following-char))
+ (shr-char-kinsoku-eol-p (following-char))))
+ (forward-char 1)))
(if failed
;; There's no breakable point, so we give it up.
- (progn
- (end-of-line)
- (while (aref fill-find-break-point-function-table (preceding-char))
- (backward-char 1))
- nil)
- (or (eolp)
- ;; Don't put kinsoku-bol characters at the beginning of a line,
- ;; or kinsoku-eol characters at the end of a line,
- (let ((count 4))
- (if (or shr-kinsoku-shorten
- (and (aref (char-category-set (preceding-char)) ?<)
- (progn
- (setq count (1- count))
- (backward-char 1)
- t)))
- (while (and
- (>= (setq count (1- count)) 0)
+ (let (found)
+ (goto-char bp)
+ (unless shr-kinsoku-shorten
+ (while (and (setq found (re-search-forward
+ "\\(\\c>\\)\\| \\|\\c<\\|\\c|"
+ (line-end-position) 'move))
+ (eq (preceding-char) ?')))
+ (if (and found (not (match-beginning 1)))
+ (goto-char (match-beginning 0)))))
+ (or
+ (eolp)
+ ;; Don't put kinsoku-bol characters at the beginning of a line,
+ ;; or kinsoku-eol characters at the end of a line.
+ (cond
+ (shr-kinsoku-shorten
+ (while (and (not (memq (preceding-char) (list ?\C-@ ?\n ? )))
+ (shr-char-kinsoku-eol-p (preceding-char)))
+ (backward-char 1))
+ (when (setq failed (= (current-column) shr-indentation))
+ ;; There's no breakable point that doesn't violate kinsoku,
+ ;; so we look for the second best position.
+ (while (and (progn
+ (forward-char 1)
+ (<= (current-column) shr-width))
+ (progn
+ (setq bp (point))
+ (shr-char-kinsoku-eol-p (following-char)))))
+ (goto-char bp)))
+ ((shr-char-kinsoku-eol-p (preceding-char))
+ (if (shr-char-kinsoku-eol-p (following-char))
+ ;; There are consecutive kinsoku-eol characters.
+ (setq failed t)
+ (let ((count 4))
+ (while
+ (progn
+ (backward-char 1)
+ (and (> (setq count (1- count)) 0)
(not (memq (preceding-char) (list ?\C-@ ?\n ? )))
- (or (aref (char-category-set (preceding-char)) ?<)
- (aref (char-category-set (following-char)) ?>)))
- (backward-char 1))
- (while (and (>= (setq count (1- count)) 0)
- (aref (char-category-set (following-char)) ?>)
- (aref fill-find-break-point-function-table
- (following-char)))
- (forward-char 1)))
- (when (eq (following-char) ? )
- (forward-char 1))
- t)))))
+ (or (shr-char-kinsoku-eol-p (preceding-char))
+ (shr-char-kinsoku-bol-p (following-char)))))))
+ (if (setq failed (= (current-column) shr-indentation))
+ ;; There's no breakable point that doesn't violate kinsoku,
+ ;; so we go to the second best position.
+ (if (looking-at "\\(\\c<+\\)\\c<")
+ (goto-char (match-end 1))
+ (forward-char 1)))))
+ (t
+ (if (shr-char-kinsoku-bol-p (preceding-char))
+ ;; There are consecutive kinsoku-bol characters.
+ (setq failed t)
+ (let ((count 4))
+ (while (and (>= (setq count (1- count)) 0)
+ (shr-char-kinsoku-bol-p (following-char))
+ (shr-char-breakable-p (following-char)))
+ (forward-char 1))))))
+ (when (eq (following-char) ? )
+ (forward-char 1))))
+ (not failed)))
(defun shr-ensure-newline ()
(unless (zerop (current-column))
(let ((image (ignore-errors
(shr-rescale-image data))))
(when image
+ ;; When inserting big-ish pictures, put them at the
+ ;; beginning of the line.
+ (when (and (> (current-column) 0)
+ (> (car (image-size image t)) 400))
+ (insert "\n"))
(insert-image image (or alt "*"))))
(insert alt)))
(search-forward "\r\n\r\n" nil t))
(buffer-substring (point) (point-max))))))
+(defun shr-image-displayer (content-function)
+ "Return a function to display an image.
+CONTENT-FUNCTION is a function to retrieve an image for a cid url that
+is an argument. The function to be returned takes three arguments URL,
+START, and END. Note that START and END should be merkers."
+ `(lambda (url start end)
+ (when url
+ (if (string-match "\\`cid:" url)
+ ,(when content-function
+ `(let ((image (funcall ,content-function
+ (substring url (match-end 0)))))
+ (when image
+ (goto-char start)
+ (shr-put-image image
+ (buffer-substring-no-properties start end))
+ (delete-region (point) end))))
+ (url-retrieve url 'shr-image-fetched
+ (list (current-buffer) start end)
+ t)))))
+
(defun shr-heading (cont &rest types)
(shr-ensure-paragraph)
(apply #'shr-fontize-cont cont types)
(autoload 'widget-convert-button "wid-edit")
-(defun shr-urlify (start url)
+(defun shr-urlify (start url &optional title)
(widget-convert-button
'url-link start (point)
- :help-echo url
+ :help-echo (if title (format "%s (%s)" url title) url)
:keymap shr-map
url)
(put-text-property start (point) 'shr-url url))
"Encode URL."
(browse-url-url-encode-chars url "[)$ ]"))
+(autoload 'shr-color-visible "shr-color")
+(autoload 'shr-color->hexadecimal "shr-color")
+
+(defun shr-color-check (fg bg)
+ "Check that FG is visible on BG.
+Returns (fg bg) with corrected values.
+Returns nil if the colors that would be used are the default
+ones, in case fg and bg are nil."
+ (when (or fg bg)
+ (let ((fixed (cond ((null fg) 'fg)
+ ((null bg) 'bg))))
+ ;; Convert colors to hexadecimal, or set them to default.
+ (let ((fg (or (shr-color->hexadecimal fg)
+ (frame-parameter nil 'foreground-color)))
+ (bg (or (shr-color->hexadecimal bg)
+ (frame-parameter nil 'background-color))))
+ (cond ((eq fixed 'bg)
+ ;; Only return the new fg
+ (list nil (cadr (shr-color-visible bg fg t))))
+ ((eq fixed 'fg)
+ ;; Invert args and results and return only the new bg
+ (list (cadr (shr-color-visible fg bg t)) nil))
+ (t
+ (shr-color-visible bg fg)))))))
+
+(defun shr-colorize-region (start end fg &optional bg)
+ (when (or fg bg)
+ (let ((new-colors (shr-color-check fg bg)))
+ (when new-colors
+ (when fg
+ (shr-put-color start end :foreground (cadr new-colors)))
+ (when bg
+ (shr-put-color start end :background (car new-colors)))))))
+
+;; Put a color in the region, but avoid putting colors on on blank
+;; text at the start of the line, and the newline at the end, to avoid
+;; ugliness. Also, don't overwrite any existing color information,
+;; since this can be called recursively, and we want the "inner" color
+;; to win.
+(defun shr-put-color (start end type color)
+ (save-excursion
+ (goto-char start)
+ (while (< (point) end)
+ (when (bolp)
+ (skip-chars-forward " "))
+ (when (> (line-end-position) (point))
+ (shr-put-color-1 (point) (min (line-end-position) end) type color))
+ (if (< (line-end-position) end)
+ (forward-line 1)
+ (goto-char end)))))
+
+(defun shr-put-color-1 (start end type color)
+ (let* ((old-props (get-text-property start 'face))
+ (do-put (not (memq type old-props)))
+ change)
+ (while (< start end)
+ (setq change (next-single-property-change start 'face nil end))
+ (when do-put
+ (put-text-property start change 'face
+ (nconc (list type color) old-props)))
+ (setq old-props (get-text-property change 'face))
+ (setq do-put (not (memq type old-props)))
+ (setq start change))
+ (when (and do-put
+ (> end start))
+ (put-text-property start end 'face
+ (nconc (list type color old-props))))))
+
;;; Tag-specific rendering rules.
+(defun shr-tag-body (cont)
+ (let* ((start (point))
+ (fgcolor (cdr (assq :fgcolor cont)))
+ (bgcolor (cdr (assq :bgcolor cont)))
+ (shr-stylesheet (list (cons 'color fgcolor)
+ (cons 'background-color bgcolor))))
+ (shr-generic cont)
+ (shr-colorize-region start (point) fgcolor bgcolor)))
+
+(defun shr-tag-style (cont)
+ )
+
+(defun shr-tag-script (cont)
+ )
+
+(defun shr-tag-label (cont)
+ (shr-generic cont)
+ (shr-ensure-paragraph))
+
(defun shr-tag-p (cont)
(shr-ensure-paragraph)
(shr-indent)
(defun shr-parse-style (style)
(when style
+ (save-match-data
+ (when (string-match "\n" style)
+ (setq style (replace-match " " t t style))))
(let ((plist nil))
(dolist (elem (split-string style ";"))
(when elem
(cadr elem))
(let ((name (replace-regexp-in-string "^ +\\| +$" "" (car elem)))
(value (replace-regexp-in-string "^ +\\| +$" "" (cadr elem))))
+ (when (string-match " *!important\\'" value)
+ (setq value (substring value 0 (match-beginning 0))))
(push (cons (intern name obarray)
value)
plist)))))
(defun shr-tag-a (cont)
(let ((url (cdr (assq :href cont)))
+ (title (cdr (assq :title cont)))
(start (point))
shr-start)
(shr-generic cont)
- (shr-urlify (or shr-start start) url)))
+ (shr-urlify (or shr-start start) url title)))
(defun shr-tag-object (cont)
(let ((start (point))
(put-text-property start (point) 'shr-alt alt)
(put-text-property start (point) 'image-url url)
(put-text-property start (point) 'image-displayer
- (lambda (url start end)
- (url-retrieve url 'shr-image-fetched
- (list (current-buffer) start end)
- t)))
+ (shr-image-displayer shr-content-function))
(put-text-property start (point) 'help-echo alt)
(setq shr-state 'image)))))
(shr-ensure-newline)
(insert (make-string shr-width shr-hr-line) "\n"))
+(defun shr-tag-title (cont)
+ (shr-heading cont 'bold 'underline))
+
+(defun shr-tag-font (cont)
+ (let* ((start (point))
+ (color (cdr (assq :color cont)))
+ (shr-stylesheet (nconc (list (cons 'color color))
+ shr-stylesheet)))
+ (shr-generic cont)
+ (when color
+ (shr-colorize-region start (point) color
+ (cdr (assq 'background-color shr-stylesheet))))))
+
;;; Table rendering algorithm.
;; Table rendering is the only complicated thing here. We do this by
(header (cdr (assq 'thead cont)))
(body (or (cdr (assq 'tbody cont)) cont))
(footer (cdr (assq 'tfoot cont)))
+ (bgcolor (cdr (assq :bgcolor cont)))
+ (start (point))
+ (shr-stylesheet (nconc (list (cons 'background-color bgcolor))
+ shr-stylesheet))
(nheader (if header (shr-max-columns header)))
(nbody (if body (shr-max-columns body)))
(nfooter (if footer (shr-max-columns footer))))
`((tr (td (table (tbody ,@footer))))))))
(if caption
`((tr (td (table (tbody ,@body)))))
- body)))))))
+ body)))))
+ (when bgcolor
+ (shr-colorize-region start (point) (cdr (assq 'color shr-stylesheet))
+ bgcolor))))
(defun shr-find-elements (cont type)
(let (result)
max)))
(dotimes (i height)
(shr-indent)
- (insert "|\n"))
+ (insert shr-table-vertical-line "\n"))
(dolist (column row)
(goto-char start)
(let ((lines (nth 2 column))
(dolist (line lines)
(setq overlay-line (pop overlay-lines))
(end-of-line)
- (insert line "|")
+ (insert line shr-table-vertical-line)
(dolist (overlay overlay-line)
(let ((o (make-overlay (- (point) (nth 0 overlay) 1)
(- (point) (nth 1 overlay) 1)))
;; possibly.
(dotimes (i (- height (length lines)))
(end-of-line)
- (insert (make-string (string-width (car lines)) ? ) "|")
+ (insert (make-string (string-width (car lines)) ? )
+ shr-table-vertical-line)
(forward-line 1)))))
(shr-insert-table-ruler widths)))
(shr-indent))
(insert shr-table-corner)
(dotimes (i (length widths))
- (insert (make-string (aref widths i) shr-table-line) shr-table-corner))
+ (insert (make-string (aref widths i) shr-table-horizontal-line)
+ shr-table-corner))
(insert "\n"))
(defun shr-table-widths (table suggested-widths)
(defun shr-render-td (cont width fill)
(with-temp-buffer
- (let ((cache (cdr (assoc (cons width cont) shr-content-cache))))
- (if cache
- (insert cache)
- (let ((shr-width width)
- (shr-indentation 0))
- (shr-generic cont))
- (delete-region
- (point)
- (+ (point)
- (skip-chars-backward " \t\n")))
- (push (cons (cons width cont) (buffer-string))
- shr-content-cache)))
- (goto-char (point-min))
- (let ((max 0))
- (while (not (eobp))
- (end-of-line)
- (setq max (max max (current-column)))
- (forward-line 1))
- (when fill
- (goto-char (point-min))
- ;; If the buffer is totally empty, then put a single blank
- ;; line here.
- (if (zerop (buffer-size))
- (insert (make-string width ? ))
- ;; Otherwise, fill the buffer.
- (while (not (eobp))
- (end-of-line)
- (when (> (- width (current-column)) 0)
- (insert (make-string (- width (current-column)) ? )))
- (forward-line 1))))
- (if fill
+ (let ((bgcolor (cdr (assq :bgcolor cont)))
+ (fgcolor (cdr (assq :fgcolor cont)))
+ (style (cdr (assq :style cont)))
+ (shr-stylesheet shr-stylesheet)
+ overlays)
+ (when style
+ (setq style (and (string-match "color" style)
+ (shr-parse-style style))))
+ (when bgcolor
+ (setq style (nconc (list (cons 'background-color bgcolor)) style)))
+ (when fgcolor
+ (setq style (nconc (list (cons 'color fgcolor)) style)))
+ (when style
+ (setq shr-stylesheet (append style shr-stylesheet)))
+ (let ((cache (cdr (assoc (cons width cont) shr-content-cache))))
+ (if cache
+ (progn
+ (insert (car cache))
+ (let ((end (length (car cache))))
+ (dolist (overlay (cadr cache))
+ (let ((new-overlay
+ (make-overlay (1+ (- end (nth 0 overlay)))
+ (1+ (- end (nth 1 overlay)))))
+ (properties (nth 2 overlay)))
+ (while properties
+ (overlay-put new-overlay
+ (pop properties) (pop properties)))))))
+ (let ((shr-width width)
+ (shr-indentation 0))
+ (shr-descend (cons 'td cont)))
+ (delete-region
+ (point)
+ (+ (point)
+ (skip-chars-backward " \t\n")))
+ (push (list (cons width cont) (buffer-string)
+ (shr-overlays-in-region (point-min) (point-max)))
+ shr-content-cache)))
+ (goto-char (point-min))
+ (let ((max 0))
+ (while (not (eobp))
+ (end-of-line)
+ (setq max (max max (current-column)))
+ (forward-line 1))
+ (when fill
+ (goto-char (point-min))
+ ;; If the buffer is totally empty, then put a single blank
+ ;; line here.
+ (if (zerop (buffer-size))
+ (insert (make-string width ? ))
+ ;; Otherwise, fill the buffer.
+ (while (not (eobp))
+ (end-of-line)
+ (when (> (- width (current-column)) 0)
+ (insert (make-string (- width (current-column)) ? )))
+ (forward-line 1))))
+ (when style
+ (shr-colorize-region
+ (point-min) (point-max)
+ (cdr (assq 'color shr-stylesheet))
+ (cdr (assq 'background-color shr-stylesheet))))
+ (if fill
+ (list max
+ (count-lines (point-min) (point-max))
+ (split-string (buffer-string) "\n")
+ (shr-collect-overlays))
(list max
- (count-lines (point-min) (point-max))
- (split-string (buffer-string) "\n")
- (shr-collect-overlays))
- (list max
- (shr-natural-width))))))
+ (shr-natural-width)))))))
(defun shr-natural-width ()
(goto-char (point-min))