Fix html link transcoder

anki-editor.el

@@ -64,6 +64,7 @@
 (require 'json)
 (require 'org-element)
 (require 'ox)
+(require 'ox-html)
 (require 'request)
 
 (defconst anki-editor-prop-note-type "ANKI_NOTE_TYPE")
@@ -196,14 +197,16 @@ The result is the path to the newly stored media file."
 (defun anki-editor-setup-minor-mode ()
   "Set up this minor mode."
   (add-hook 'org-property-allowed-value-functions #'anki-editor--get-allowed-values-for-property)
-  (advice-add 'org-set-tags :before #'anki-editor--before-set-tags))
+  (advice-add 'org-set-tags :before #'anki-editor--before-set-tags)
+  (advice-add 'org-html-link :around #'anki-editor--ox-html-link))
 
 (defun anki-editor-teardown-minor-mode ()
   "Tear down this minor mode."
   (remove-hook 'org-property-allowed-value-functions #'anki-editor--get-allowed-values-for-property)
   (advice-remove 'org-set-tags #'anki-editor--before-set-tags)
   (when (advice-member-p 'anki-editor--get-buffer-tags #'org-get-buffer-tags)
-    (advice-remove 'org-get-buffer-tags #'anki-editor--get-buffer-tags)))
+    (advice-remove 'org-get-buffer-tags #'anki-editor--get-buffer-tags))
+  (advice-remove 'org-html-link #'anki-editor--ox-html-link))
 
 
 ;;; Commands
@@ -527,8 +530,7 @@ Do nothing when JUST-ALIGN is non-nil."
   (org-export-create-backend
    :parent 'html
    :transcoders '((latex-fragment . anki-editor--ox-latex)
-                  (latex-environment . anki-editor--ox-latex)
+                  (latex-environment . anki-editor--ox-latex))))
-                  (link . anki-editor--ox-link))))
 
 (defconst anki-editor--anki-latex-syntax-map
   `((,(format "^%s" (regexp-quote "$$")) . "[$$]")
@@ -564,145 +566,63 @@ CONTENTS is nil.  INFO is a plist holding contextual information."
         (replace-regexp-in-string "}}" "} } " code)
       code)))
 
-;; FIXME: since some functions get added and some get removed in
+(defun anki-editor--ox-html-link (oldfun link desc info)
-;; differenct versions of Org, this is going to break
+  "When LINK is a link to local file, transcodes it to html and stores the target file to Anki, otherwise calls OLDFUN for help.
-(defun anki-editor--ox-link (link desc info)
+The implementation is borrowed and simplified from ox-html."
-  "Transcode a LINK object from Org to HTML.
+  (or (catch 'giveup
-DESC is the description part of the link, or the empty string.
+        (let* ((type (org-element-property :type link))
-INFO is a plist holding contextual information.  THE
+               (raw-path (org-element-property :path link))
-IMPLEMENTATION IS BASICALLY COPIED AND SIMPLIFIED FROM
+               (desc (org-string-nw-p desc))
-ox-html.el :)"
+               (path
-  (let* ((type (org-element-property :type link))
+                (cond
-         (raw-path (org-element-property :path link))
+                 ((string= type "file")
-         ;; Ensure DESC really exists, or set it to nil.
+                  ;; Possibly append `:html-link-home' to relative file
-         (desc (org-string-nw-p desc))
+                  ;; name.
-         (path
+                  (let ((inhibit-message nil)
+                        (home (and (plist-get info :html-link-home)
+                                   (org-trim (plist-get info :html-link-home)))))
+                    (when (and home
+                               (plist-get info :html-link-use-abs-url)
+                               (file-name-absolute-p raw-path))
+                      (setq raw-path (concat (file-name-as-directory home) raw-path)))
+                    (message "Storing media file to Anki for %s..." raw-path)
+                    ;; storing file to Anki and return the modified path
+                    (anki-editor--anki-connect-store-media-file (expand-file-name (url-unhex-string raw-path)))))
+                 (t (throw 'giveup nil))))
+               (attributes-plist
+                (let* ((parent (org-export-get-parent-element link))
+                       (link (let ((container (org-export-get-parent link)))
+                               (if (and (eq (org-element-type container) 'link)
+                                        (org-html-inline-image-p link info))
+                                   container
+                                 link))))
+                  (and (eq (org-element-map parent 'link 'identity info t) link)
+                       (org-export-read-attribute :attr_html parent))))
+               (attributes
+                (let ((attr (org-html--make-attribute-string attributes-plist)))
+                  (if (org-string-nw-p attr) (concat " " attr) ""))))
           (cond
-           ((member type '("http" "https" "ftp" "mailto" "news"))
+           ;; Image file.
-            (url-encode-url (org-link-unescape (concat type ":" raw-path))))
+           ((and (plist-get info :html-inline-images)
-           ((string= type "file")
+                 (org-export-inline-image-p
-            ;; Possibly append `:html-link-home' to relative file
+                  link (plist-get info :html-inline-image-rules)))
-            ;; name.
+            (org-html--format-image path attributes-plist info))
-            (let ((home (and (plist-get info :html-link-home)
+
-                             (org-trim (plist-get info :html-link-home)))))
+           ;; External link with a description part.
-              (when (and home
+           ((and path desc) (format "<a href=\"%s\"%s>%s</a>"
-                         (plist-get info :html-link-use-abs-url)
+                                    (org-html-encode-plain-text path)
-                         (file-name-absolute-p raw-path))
+                                    attributes
-                (setq raw-path (concat (file-name-as-directory home) raw-path)))
+                                    desc))
-              (message "Storing media file to Anki for %s..." raw-path)
+
-              (anki-editor--anki-connect-store-media-file (expand-file-name (url-unhex-string raw-path)))))
+           ;; External link without a description part.
-           (t raw-path)))
+           (path (let ((path (org-html-encode-plain-text path)))
-          ;; Extract attributes from parent's paragraph.  HACK: Only do
+                   (format "<a href=\"%s\"%s>%s</a>"
-          ;; this for the first link in parent (inner image link for
+                           path
-          ;; inline images).  This is needed as long as attributes
+                           attributes
-          ;; cannot be set on a per link basis.
+                           (org-link-unescape path))))
-          (attributes-plist
+
-           (let* ((parent (org-export-get-parent-element link))
+           (t (throw 'giveup nil)))))
-                  (link (let ((container (org-export-get-parent link)))
+      (funcall oldfun link desc info)))
-                          (if (and (eq (org-element-type container) 'link)
-                                   (org-html-inline-image-p link info))
-                              container
-                            link))))
-             (and (eq (org-element-map parent 'link 'identity info t) link)
-                  (org-export-read-attribute :attr_html parent))))
-          (attributes
-           (let ((attr (org-html--make-attribute-string attributes-plist)))
-             (if (org-string-nw-p attr) (concat " " attr) ""))))
-         (cond
-          ;; Image file.
-          ((and (plist-get info :html-inline-images)
-                (org-export-inline-image-p
-                 link (plist-get info :html-inline-image-rules)))
-           (org-html--format-image path attributes-plist info))
-          ;; Radio target: Transcode target's contents and use them as
-          ;; link's description.
-          ((string= type "radio")
-           (let ((destination (org-export-resolve-radio-link link info)))
-             (if (not destination) desc
-               (format "<a href=\"#%s\"%s>%s</a>"
-                       (org-export-get-reference destination info)
-                       attributes
-                       desc))))
-          ;; Links pointing to a headline: Find destination and build
-          ;; appropriate referencing command.
-          ((member type '("custom-id" "fuzzy" "id"))
-           (let ((destination (if (string= type "fuzzy")
-                                  (org-export-resolve-fuzzy-link link info)
-                                (org-export-resolve-id-link link info))))
-             (pcase (org-element-type destination)
-               ;; ID link points to an external file.
-               (`plain-text
-                (let ((fragment (concat "ID-" path)))
-                  (format "<a href=\"%s#%s\"%s>%s</a>"
-                          destination fragment attributes (or desc destination))))
-               ;; Fuzzy link points nowhere.
-               (`nil
-                (format "<i>%s</i>"
-                        (or desc
-                            (org-export-data
-                             (org-element-property :raw-link link) info))))
-               ;; Link points to a headline.
-               (`headline
-                (let ((href (or (org-element-property :CUSTOM_ID destination)
-                                (org-export-get-reference destination info)))
-                      ;; What description to use?
-                      (desc
-                       ;; Case 1: Headline is numbered and LINK has no
-                       ;; description.  Display section number.
-                       (if (and (org-export-numbered-headline-p destination info)
-                                (not desc))
-                           (mapconcat #'number-to-string
-                                      (org-export-get-headline-number
-                                       destination info) ".")
-                         ;; Case 2: Either the headline is un-numbered or
-                         ;; LINK has a custom description.  Display LINK's
-                         ;; description or headline's title.
-                         (or desc
-                             (org-export-data
-                              (org-element-property :title destination) info)))))
-                  (format "<a href=\"#%s\"%s>%s</a>" href attributes desc)))
-               ;; Fuzzy link points to a target or an element.
-               (_
-                (let* ((ref (org-export-get-reference destination info))
-                       (number (cond
-                                (desc nil)
-                                ((org-html-standalone-image-p destination info)
-                                 (org-export-get-ordinal
-                                  (org-element-map destination 'link
-                                    #'identity info t)
-                                  info 'link 'org-html-standalone-image-p))
-                                (t (org-export-get-ordinal
-                                    destination info nil 'org-html--has-caption-p))))
-                       (desc (cond (desc)
-                                   ((not number) "No description for this link")
-                                   ((numberp number) (number-to-string number))
-                                   (t (mapconcat #'number-to-string number ".")))))
-                  (format "<a href=\"#%s\"%s>%s</a>" ref attributes desc))))))
-          ;; Coderef: replace link with the reference name or the
-          ;; equivalent line number.
-          ((string= type "coderef")
-           (let ((fragment (concat "coderef-" (org-html-encode-plain-text path))))
-             (format "<a href=\"#%s\" %s%s>%s</a>"
-                     fragment
-                     (format "class=\"coderef\" onmouseover=\"CodeHighlightOn(this, \
-'%s');\" onmouseout=\"CodeHighlightOff(this, '%s');\""
-                             fragment fragment)
-                     attributes
-                     (format (org-export-get-coderef-format path desc)
-                             (org-export-resolve-coderef path info)))))
-          ;; External link with a description part.
-          ((and path desc) (format "<a href=\"%s\"%s>%s</a>"
-                                   (org-html-encode-plain-text path)
-                                   attributes
-                                   desc))
-          ;; External link without a description part.
-          (path (let ((path (org-html-encode-plain-text path)))
-                  (format "<a href=\"%s\"%s>%s</a>"
-                          path
-                          attributes
-                          (org-link-unescape path))))
-          ;; No path, only description.  Try to do something useful.
-          (t (format "<i>%s</i>" desc)))))
 
 
 ;;; Utilities