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+;;; xwidget.el --- api functions for xwidgets  -*- lexical-binding: t -*-
+;;
+;; Copyright (C) 2011-2016 Free Software Foundation, Inc.
+;;
+;; Author: Joakim Verona (joakim@verona.se)
+;;
+;; 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 3 of the License, 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.  If not, see <http://www.gnu.org/licenses/>.
+;;
+;; --------------------------------------------------------------------
+
+;;; Commentary:
+;;
+;; See xwidget.c for more api functions.
+
+;; TODO this breaks compilation when we don't have xwidgets.
+;;(require 'xwidget-internal)
+
+;;; Code:
+
+(require 'cl-lib)
+(require 'bookmark)
+
+(defcustom xwidget-webkit-scroll-behaviour 'native
+  "Scroll behaviour of the webkit instance.
+'native or 'image."
+  :version "25.1"
+  :group 'frames   ; TODO add xwidgets group if more options are added
+  :type '(choice (const native) (const image)))
+
+(declare-function make-xwidget "xwidget.c"
+                  (beg end type title width height arguments &optional buffer))
+(declare-function xwidget-set-adjustment "xwidget.c"
+                  (xwidget axis relative value))
+(declare-function xwidget-buffer "xwidget.c" (xwidget))
+(declare-function xwidget-webkit-get-title "xwidget.c" (xwidget))
+(declare-function xwidget-size-request "xwidget.c" (xwidget))
+(declare-function xwidget-resize "xwidget.c" (xwidget new-width new-height))
+(declare-function xwidget-webkit-execute-script "xwidget.c" (xwidget script))
+(declare-function xwidget-webkit-goto-uri "xwidget.c" (xwidget uri))
+(declare-function xwidget-plist "xwidget.c" (xwidget))
+(declare-function set-xwidget-plist "xwidget.c" (xwidget plist))
+(declare-function xwidget-view-window "xwidget.c" (xwidget-view))
+(declare-function xwidget-view-model "xwidget.c" (xwidget-view))
+(declare-function delete-xwidget-view "xwidget.c" (xwidget-view))
+(declare-function get-buffer-xwidgets "xwidget.c" (buffer))
+
+(defun xwidget-insert (pos type title width height &optional args)
+  "Insert an xwidget at POS.
+given ID, TYPE, TITLE WIDTH and
+HEIGHT in the current buffer.
+
+Return ID
+
+see `make-xwidget' for types suitable for TYPE.
+Optional argument ARGS usage depends on the xwidget."
+  (goto-char pos)
+  (let ((id (make-xwidget (point) (point)
+                          type title width height args)))
+    (put-text-property (point) (+ 1 (point))
+                       'display (list 'xwidget ':xwidget id))
+    id))
+
+(defun xwidget-at (pos)
+  "Return xwidget at POS."
+  ;; TODO this function is a bit tedious because the C layer isn't well
+  ;; protected yet and xwidgetp apparently doesn't work yet.
+  (let* ((disp (get-text-property pos 'display))
+         (xw (car (cdr (cdr  disp)))))
+    ;;(if (xwidgetp  xw) xw nil)
+    (if (equal 'xwidget (car disp)) xw)))
+
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;; webkit support
+(require 'browse-url)
+(require 'image-mode);;for some image-mode alike functionality
+
+;;;###autoload
+(defun xwidget-webkit-browse-url (url &optional new-session)
+  "Ask xwidget-webkit to browse URL.
+NEW-SESSION specifies whether to create a new xwidget-webkit session.  URL
+defaults to the string looking like a url around the cursor position."
+  (interactive (progn
+                 (require 'browse-url)
+                 (browse-url-interactive-arg "xwidget-webkit URL: "
+                                             ;;(xwidget-webkit-current-url)
+                                             )))
+  (when (stringp url)
+    (if new-session
+        (xwidget-webkit-new-session url)
+      (xwidget-webkit-goto-url url))))
+
+;;todo.
+;; - check that the webkit support is compiled in
+(defvar xwidget-webkit-mode-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map "g" 'xwidget-webkit-browse-url)
+    (define-key map "a" 'xwidget-webkit-adjust-size-dispatch)
+    (define-key map "b" 'xwidget-webkit-back)
+    (define-key map "r" 'xwidget-webkit-reload)
+    (define-key map "t" (lambda () (interactive) (message "o"))) ;FIXME: ?!?
+    (define-key map "\C-m" 'xwidget-webkit-insert-string)
+    (define-key map "w" 'xwidget-webkit-current-url)
+
+    ;;similar to image mode bindings
+    (define-key map (kbd "SPC")                 'xwidget-webkit-scroll-up)
+    (define-key map (kbd "DEL")                 'xwidget-webkit-scroll-down)
+
+    (define-key map [remap scroll-up]           'xwidget-webkit-scroll-up)
+    (define-key map [remap scroll-up-command]   'xwidget-webkit-scroll-up)
+
+    (define-key map [remap scroll-down]         'xwidget-webkit-scroll-down)
+    (define-key map [remap scroll-down-command] 'xwidget-webkit-scroll-down)
+
+    (define-key map [remap forward-char]        'xwidget-webkit-scroll-forward)
+    (define-key map [remap backward-char]       'xwidget-webkit-scroll-backward)
+    (define-key map [remap right-char]          'xwidget-webkit-scroll-forward)
+    (define-key map [remap left-char]           'xwidget-webkit-scroll-backward)
+    ;; (define-key map [remap previous-line]          'image-previous-line)
+    ;; (define-key map [remap next-line]              'image-next-line)
+
+    ;; (define-key map [remap move-beginning-of-line] 'image-bol)
+    ;; (define-key map [remap move-end-of-line]       'image-eol)
+    ;; (define-key map [remap beginning-of-buffer]    'image-bob)
+    ;; (define-key map [remap end-of-buffer]          'image-eob)
+    map)
+  "Keymap for `xwidget-webkit-mode'.")
+
+(defun xwidget-webkit-scroll-up ()
+  "Scroll webkit up,either native or like image mode."
+  (interactive)
+  (if (eq xwidget-webkit-scroll-behaviour 'native)
+      (xwidget-set-adjustment (xwidget-webkit-last-session) 'vertical t 50)
+    (image-scroll-up)))
+
+(defun xwidget-webkit-scroll-down ()
+  "Scroll webkit down,either native or like image mode."
+  (interactive)
+  (if (eq xwidget-webkit-scroll-behaviour 'native)
+      (xwidget-set-adjustment (xwidget-webkit-last-session) 'vertical t -50)
+    (image-scroll-down)))
+
+(defun xwidget-webkit-scroll-forward ()
+  "Scroll webkit forward,either native or like image mode."
+  (interactive)
+  (if (eq xwidget-webkit-scroll-behaviour 'native)
+      (xwidget-set-adjustment (xwidget-webkit-last-session) 'horizontal t 50)
+    (xwidget-webkit-scroll-forward)))
+
+(defun xwidget-webkit-scroll-backward ()
+  "Scroll webkit backward,either native or like image mode."
+  (interactive)
+  (if (eq xwidget-webkit-scroll-behaviour 'native)
+      (xwidget-set-adjustment (xwidget-webkit-last-session) 'horizontal t -50)
+    (xwidget-webkit-scroll-backward)))
+
+
+;; The xwidget event needs to go into a higher level handler
+;; since the xwidget can generate an event even if it's offscreen.
+;; TODO this needs to use callbacks and consider different xwidget event types.
+(define-key (current-global-map) [xwidget-event] #'xwidget-event-handler)
+(defun xwidget-log (&rest msg)
+  "Log MSG to a buffer."
+  (let ((buf (get-buffer-create " *xwidget-log*")))
+    (with-current-buffer buf
+      (insert (apply #'format msg))
+      (insert "\n"))))
+
+(defun xwidget-event-handler ()
+  "Receive xwidget event."
+  (interactive)
+  (xwidget-log "stuff happened to xwidget %S" last-input-event)
+  (let*
+      ((xwidget-event-type (nth 1 last-input-event))
+       (xwidget (nth 2 last-input-event))
+       ;;(xwidget-callback (xwidget-get xwidget 'callback))
+       ;;TODO stopped working for some reason
+       )
+    ;;(funcall  xwidget-callback xwidget xwidget-event-type)
+    (message "xw callback %s" xwidget)
+    (funcall  'xwidget-webkit-callback xwidget xwidget-event-type)))
+
+(defun xwidget-webkit-callback (xwidget xwidget-event-type)
+  "Callback for xwidgets.
+XWIDGET instance, XWIDGET-EVENT-TYPE depends on the originating xwidget."
+  (if (not (buffer-live-p (xwidget-buffer xwidget)))
+      (xwidget-log
+       "error: callback called for xwidget with dead buffer")
+    (with-current-buffer (xwidget-buffer xwidget)
+      (let* ((strarg  (nth 3 last-input-event)))
+        (cond ((eq xwidget-event-type 'document-load-finished)
+               (xwidget-log "webkit finished loading: '%s'"
+                            (xwidget-webkit-get-title xwidget))
+               ;;TODO - check the native/internal scroll
+               ;;(xwidget-adjust-size-to-content xwidget)
+               (xwidget-webkit-adjust-size-dispatch) ;;TODO xwidget arg
+               (rename-buffer (format "*xwidget webkit: %s *"
+                                      (xwidget-webkit-get-title xwidget)))
+               (pop-to-buffer (current-buffer)))
+              ((eq xwidget-event-type
+                   'navigation-policy-decision-requested)
+               (if (string-match ".*#\\(.*\\)" strarg)
+                   (xwidget-webkit-show-id-or-named-element
+                    xwidget
+                    (match-string 1 strarg))))
+              (t (xwidget-log "unhandled event:%s" xwidget-event-type)))))))
+
+(defvar bookmark-make-record-function)
+(define-derived-mode xwidget-webkit-mode
+    special-mode "xwidget-webkit" "Xwidget webkit view mode."
+    (setq buffer-read-only t)
+    (setq-local bookmark-make-record-function
+                #'xwidget-webkit-bookmark-make-record)
+    ;; Keep track of [vh]scroll when switching buffers
+    (image-mode-setup-winprops))
+
+(defun xwidget-webkit-bookmark-make-record ()
+  "Integrate Emacs bookmarks with the webkit xwidget."
+  (nconc (bookmark-make-record-default t t)
+         `((page     . ,(xwidget-webkit-current-url))
+           (handler  . (lambda (bmk) (browse-url
+                                 (bookmark-prop-get bmk 'page)))))))
+
+
+(defvar xwidget-webkit-last-session-buffer nil)
+
+(defun xwidget-webkit-last-session ()
+  "Last active webkit, or nil."
+  (if (buffer-live-p xwidget-webkit-last-session-buffer)
+      (with-current-buffer xwidget-webkit-last-session-buffer
+        (xwidget-at (point-min)))
+    nil))
+
+(defun xwidget-webkit-current-session ()
+  "Either the webkit in the current buffer, or the last one used.
+The latter might be nil."
+  (or (xwidget-at (point-min)) (xwidget-webkit-last-session)))
+
+(defun xwidget-adjust-size-to-content (xw)
+  "Resize XW to content."
+  ;; xwidgets doesn't support widgets that have their own opinions about
+  ;; size well, yet this reads the desired size and resizes the Emacs
+  ;; allocated area accordingly.
+  (let ((size (xwidget-size-request xw)))
+    (xwidget-resize xw (car size) (cadr size))))
+
+
+(defvar xwidget-webkit-activeelement-js"
+function findactiveelement(doc){
+//alert(doc.activeElement.value);
+   if(doc.activeElement.value != undefined){
+      return doc.activeElement;
+   }else{
+        // recurse over the child documents:
+        var frames = doc.getElementsByTagName('frame');
+        for (var i = 0; i < frames.length; i++)
+        {
+                var d = frames[i].contentDocument;
+                 var rv = findactiveelement(d);
+                 if(rv != undefined){
+                    return rv;
+                 }
+        }
+    }
+    return undefined;
+};
+
+
+"
+
+  "javascript that finds the active element."
+  ;; Yes it's ugly, because:
+  ;; - there is apparently no way to find the active frame other than recursion
+  ;; - the js "for each" construct misbehaved on the "frames" collection
+  ;; - a window with no frameset still has frames.length == 1, but
+  ;; frames[0].document.activeElement != document.activeElement
+  ;;TODO the activeelement type needs to be examined, for iframe, etc.
+  )
+
+(defun xwidget-webkit-insert-string (xw str)
+  "Insert string in the active field in the webkit.
+Argument XW webkit.
+Argument STR string."
+  ;; Read out the string in the field first and provide for edit.
+  (interactive
+   (let* ((xww (xwidget-webkit-current-session))
+
+          (field-value
+           (progn
+             (xwidget-webkit-execute-script xww xwidget-webkit-activeelement-js)
+             (xwidget-webkit-execute-script-rv
+              xww
+              "findactiveelement(document).value;")))
+          (field-type (xwidget-webkit-execute-script-rv
+                       xww
+                       "findactiveelement(document).type;")))
+     (list xww
+           (cond ((equal "text" field-type)
+                  (read-string "text:" field-value))
+                 ((equal "password" field-type)
+                  (read-passwd "password:" nil field-value))
+                 ((equal "textarea" field-type)
+                  (xwidget-webkit-begin-edit-textarea xww field-value))))))
+  (xwidget-webkit-execute-script
+   xw
+   (format "findactiveelement(document).value='%s'" str)))
+
+(defvar xwidget-xwbl)
+(defun xwidget-webkit-begin-edit-textarea (xw text)
+  "Start editing of a webkit text area.
+XW is the xwidget identifier, TEXT is retrieved from the webkit."
+  (switch-to-buffer
+   (generate-new-buffer "textarea"))
+
+  (set (make-local-variable 'xwidget-xwbl) xw)
+  (insert text))
+
+(defun xwidget-webkit-end-edit-textarea ()
+  "End editing of a webkit text area."
+  (interactive)
+  (goto-char (point-min))
+  (while (search-forward "\n" nil t)
+    (replace-match "\\n" nil t))
+  (xwidget-webkit-execute-script
+   xwidget-xwbl
+   (format "findactiveelement(document).value='%s'"
+           (buffer-substring (point-min) (point-max))))
+  ;;TODO convert linefeed to \n
+  )
+
+(defun xwidget-webkit-show-named-element (xw element-name)
+  "Make named-element show.  for instance an anchor.
+Argument XW is the xwidget.
+Argument ELEMENT-NAME is the element name to display in the webkit xwidget."
+  (interactive (list (xwidget-webkit-current-session)
+                     (read-string "element name:")))
+  ;;TODO since an xwidget is an Emacs object, it is not trivial to do
+  ;; some things that are taken for granted in a normal browser.
+  ;; scrolling an anchor/named-element into view is one such thing.
+  ;; This function implements a proof-of-concept for this.  Problems
+  ;; remaining: - The selected window is scrolled but this is not
+  ;; always correct - This needs to be interfaced into browse-url
+  ;; somehow.  The tricky part is that we need to do this in two steps:
+  ;; A: load the base url, wait for load signal to arrive B: navigate
+  ;; to the anchor when the base url is finished rendering
+
+  ;; This part figures out the Y coordinate of the element
+  (let ((y (string-to-number
+            (xwidget-webkit-execute-script-rv
+             xw
+             (format
+              "document.getElementsByName('%s')[0].getBoundingClientRect().top"
+              element-name)
+             0))))
+    ;; Now we need to tell Emacs to scroll the element into view.
+    (xwidget-log "scroll: %d" y)
+    (set-window-vscroll (selected-window) y t)))
+
+(defun xwidget-webkit-show-id-element (xw element-id)
+  "Make id-element show.  for instance an anchor.
+Argument XW is the webkit xwidget.
+Argument ELEMENT-ID is the id of the element to show."
+  (interactive (list (xwidget-webkit-current-session)
+                     (read-string "element id:")))
+  (let ((y (string-to-number
+            (xwidget-webkit-execute-script-rv
+             xw
+             (format "document.getElementById('%s').getBoundingClientRect().top"
+                     element-id)
+             0))))
+    ;; Now we need to tell Emacs to scroll the element into view.
+    (xwidget-log "scroll: %d" y)
+    (set-window-vscroll (selected-window) y t)))
+
+(defun xwidget-webkit-show-id-or-named-element (xw element-id)
+  "Make id-element show.  for instance an anchor.
+Argument XW is the webkit xwidget.
+Argument ELEMENT-ID is either a name or an element id."
+  (interactive (list (xwidget-webkit-current-session)
+                     (read-string "element id:")))
+  (let* ((y1 (string-to-number
+              (xwidget-webkit-execute-script-rv
+               xw
+               (format "document.getElementsByName('%s')[0].getBoundingClientRect().top" element-id)
+               "0")))
+         (y2 (string-to-number
+              (xwidget-webkit-execute-script-rv
+               xw
+               (format "document.getElementById('%s').getBoundingClientRect().top" element-id)
+               "0")))
+         (y3 (max y1 y2)))
+    ;; Now we need to tell Emacs to scroll the element into view.
+    (xwidget-log "scroll: %d" y3)
+    (set-window-vscroll (selected-window) y3 t)))
+
+(defun xwidget-webkit-adjust-size-to-content ()
+  "Adjust webkit to content size."
+  (interactive)
+  (xwidget-adjust-size-to-content (xwidget-webkit-current-session)))
+
+(defun xwidget-webkit-adjust-size-dispatch ()
+  "Adjust size according to mode."
+  (interactive)
+  (if (eq xwidget-webkit-scroll-behaviour 'native)
+      (xwidget-webkit-adjust-size-to-window)
+    (xwidget-webkit-adjust-size-to-content))
+  ;; The recenter is intended to correct a visual glitch.
+  ;; It errors out if the buffer isn't visible, but then we don't get
+  ;; the glitch, so silence errors.
+  (ignore-errors
+    (recenter-top-bottom))
+  )
+
+(defun xwidget-webkit-adjust-size-to-window ()
+  "Adjust webkit to window."
+  (interactive)
+  (xwidget-resize (xwidget-webkit-current-session) (window-pixel-width)
+                  (window-pixel-height)))
+
+(defun xwidget-webkit-adjust-size (w h)
+  "Manually set webkit size.
+Argument W width.
+Argument H height."
+  ;; TODO shouldn't be tied to the webkit xwidget
+  (interactive "nWidth:\nnHeight:\n")
+  (xwidget-resize (xwidget-webkit-current-session) w h))
+
+(defun xwidget-webkit-fit-width ()
+  "Adjust width of webkit to window width."
+  (interactive)
+  (xwidget-webkit-adjust-size (- (nth 2 (window-inside-pixel-edges))
+                                 (car (window-inside-pixel-edges)))
+                              1000))
+
+(defun xwidget-webkit-new-session (url)
+  "Create a new webkit session buffer with URL."
+  (let*
+      ((bufname (generate-new-buffer-name "*xwidget-webkit*"))
+       xw)
+    (setq xwidget-webkit-last-session-buffer (switch-to-buffer
+                                              (get-buffer-create bufname)))
+    (insert " 'a' adjusts the xwidget size.")
+    (setq xw (xwidget-insert 1 'webkit-osr  bufname 1000 1000))
+    (xwidget-put xw 'callback 'xwidget-webkit-callback)
+    (xwidget-webkit-mode)
+    (xwidget-webkit-goto-uri (xwidget-webkit-last-session) url)))
+
+
+(defun xwidget-webkit-goto-url (url)
+  "Goto URL."
+  (if (xwidget-webkit-current-session)
+      (progn
+        (xwidget-webkit-goto-uri (xwidget-webkit-current-session) url))
+    (xwidget-webkit-new-session url)))
+
+(defun xwidget-webkit-back ()
+  "Back in history."
+  (interactive)
+  (xwidget-webkit-execute-script (xwidget-webkit-current-session)
+                                 "history.go(-1);"))
+
+(defun xwidget-webkit-reload ()
+  "Reload current url."
+  (interactive)
+  (xwidget-webkit-execute-script (xwidget-webkit-current-session)
+                                 "history.go(0);"))
+
+(defun xwidget-webkit-current-url ()
+  "Get the webkit url.  place it on kill ring."
+  (interactive)
+  (let* ((rv (xwidget-webkit-execute-script-rv (xwidget-webkit-current-session)
+                                               "document.URL"))
+         (url (kill-new (or rv ""))))
+    (message "url: %s" url)
+    url))
+
+(defun xwidget-webkit-execute-script-rv (xw script &optional default)
+  "Same as 'xwidget-webkit-execute-script' but but with return value.
+XW is the webkit instance.  SCRIPT is the script to execute.
+DEFAULT is the defaultreturn value."
+  ;; Notice the ugly "title" hack.  It is needed because the Webkit
+  ;; API at the time of writing didn't support returning values.  This
+  ;; is a wrapper for the title hack so it's easy to remove should
+  ;; Webkit someday support JS return values or we find some other way
+  ;; to access the DOM.
+
+  ;; Reset webkit title.  Not very nice.
+  (let* ((emptytag "titlecantbewhitespaceohthehorror")
+         title)
+    (xwidget-webkit-execute-script xw (format "document.title=\"%s\";"
+                                              (or default emptytag)))
+    (xwidget-webkit-execute-script xw (format "document.title=%s;" script))
+    (setq title (xwidget-webkit-get-title xw))
+    (if (equal emptytag title)
+        (setq title ""))
+    (unless title
+      (setq title default))
+    title))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+(defun xwidget-webkit-get-selection ()
+  "Get the webkit selection."
+  (xwidget-webkit-execute-script-rv (xwidget-webkit-current-session)
+                                    "window.getSelection().toString();"))
+
+(defun xwidget-webkit-copy-selection-as-kill ()
+  "Get the webkit selection and put it on the kill ring."
+  (interactive)
+  (kill-new (xwidget-webkit-get-selection)))
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; Xwidget plist management (similar to the process plist functions)
+
+(defun xwidget-get (xwidget propname)
+  "Return the value of XWIDGET' PROPNAME property.
+This is the last value stored with `(xwidget-put XWIDGET PROPNAME VALUE)'."
+  (plist-get (xwidget-plist xwidget) propname))
+
+(defun xwidget-put (xwidget propname value)
+  "Change XWIDGET' PROPNAME property to VALUE.
+It can be retrieved with `(xwidget-get XWIDGET PROPNAME)'."
+  (set-xwidget-plist xwidget
+                     (plist-put (xwidget-plist xwidget) propname value)))
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(defvar xwidget-view-list)              ; xwidget.c
+(defvar xwidget-list)                   ; xwidget.c
+
+(defun xwidget-delete-zombies ()
+  "Helper for `xwidget-cleanup'."
+  (dolist (xwidget-view xwidget-view-list)
+    (when (or (not (window-live-p (xwidget-view-window xwidget-view)))
+              (not (memq (xwidget-view-model xwidget-view)
+                         xwidget-list)))
+      (delete-xwidget-view xwidget-view))))
+
+(defun xwidget-cleanup ()
+  "Delete zombie xwidgets."
+  ;; During development it was sometimes easy to wind up with zombie
+  ;; xwidget instances.
+  ;; This function tries to implement a workaround should it occur again.
+  (interactive)
+  ;; Kill xviews that should have been deleted but still linger.
+  (xwidget-delete-zombies)
+  ;; Redraw display otherwise ghost of zombies will remain to haunt the screen
+  (redraw-display))
+
+(defun xwidget-kill-buffer-query-function ()
+  "Ask before killing a buffer that has xwidgets."
+  (let ((xwidgets (get-buffer-xwidgets (current-buffer))))
+    (or (not xwidgets)
+        (not (memq t (mapcar #'xwidget-query-on-exit-flag xwidgets)))
+        (yes-or-no-p
+         (format "Buffer %S has xwidgets; kill it? " (buffer-name))))))
+
+(when (featurep 'xwidget-internal)
+  (add-hook 'kill-buffer-query-functions #'xwidget-kill-buffer-query-function)
+  ;; This would have felt better in C, but this seems to work well in
+  ;; practice though.
+  (add-hook 'window-configuration-change-hook #'xwidget-delete-zombies))
+
+(provide 'xwidget)
+;;; xwidget.el ends here