(defun my-supernote-upload (filename &optional supernote-path)
  (interactive "FFile: ")
  (setq supernote-path (or supernote-path "/INBOX"))
  (let* ((boundary (mml-compute-boundary '()))
         (url-request-method "POST")
         (url-request-extra-headers
          `(("Content-Type" . ,(format "multipart/form-data; boundary=%s" boundary))))
         (url-request-data
          (mm-url-encode-multipart-form-data
           `(("file" . (("name" . "file")
                        ("filename" . ,(file-name-nondirectory filename))
                        ("content-type" . "application/octet-stream")
                        ("filedata" . ,(with-temp-buffer
                                         (insert-file-contents-literally filename)
                                         (buffer-substring-no-properties (point-min) (point-max)))))))
           boundary)))
    (with-current-buffer
        (url-retrieve-synchronously
         (format "http://%s:8089%s" my-supernote-ip-address supernote-path))
      (re-search-backward "^$")
      (prog1 (json-read)
        (kill-buffer)))))

(defun my-supernote-org-upload-as-text (&optional async subtree visible-only body-only ext-plist)
  "Export Org format, but save it with a .txt extension."
  (interactive (list nil current-prefix-arg))
  (let ((filename (org-export-output-file-name ".txt" subtree))
        (text (org-export-as 'org subtree visible-only body-only ext-plist)))
    ;; consider copying instead of exporting so that #+begin_export html etc. is preserved
    (with-temp-file filename
      (insert text))
    (my-supernote-upload filename)))

(defun my-supernote-org-upload-as-pdf (&optional async subtree visible-only body-only ext-plist)
  (interactive (list nil current-prefix-arg))
  (my-supernote-upload (org-latex-export-to-pdf async subtree visible-only body-only ext-plist)))

(defun my-supernote-org-upload-as-epub (&optional async subtree visible-only body-only ext-plist)
  (interactive (list nil current-prefix-arg))
  (my-supernote-upload (org-epub-export-to-epub async subtree visible-only ext-plist)))

(org-export-define-backend
    'supernote nil
    :menu-entry '(?s "Supernote"
                     ((?s "as PDF" my-supernote-org-upload-as-pdf)
                      (?e "as EPUB" my-supernote-org-upload-as-epub)
                      (?o "as Org" my-supernote-org-upload-as-text))))

(defun my-ox-link-path (link _ info)
  (let* ((raw-path (org-element-property :path link)))
    (setq raw-path
          (org-export-file-uri
           (org-publish-file-relative-name raw-path info)))
    ;; Possibly append `:html-link-home' to relative file
    ;; name.
    (let ((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)
                 (not (file-name-absolute-p raw-path)))
        (setq raw-path (concat (file-name-as-directory home) raw-path))))
    raw-path))

(defun my-org-html-link (link desc info)
  (if (and
       (string= (org-element-property :type link) "file")
       (not (plist-get (org-export-read-attribute :attr_html (org-element-parent-element link))
                       :data-link))
       (org-export-inline-image-p link (plist-get info :html-inline-image-rules)))
      (let ((path (org-element-property :path link)))
        (if (string= (file-name-extension path) "svg")
            (with-temp-buffer
              (insert-file-contents-literally path)
              (buffer-string))
          (org-html-link link desc info)))
    (org-html-link link desc info)))

(defun my-org-md-link (link desc info)
  (if (and (string= (org-element-property :type link) "file")
           (not (plist-get (org-export-read-attribute :attr_html (org-element-parent-element link))
                       :data-link)))
      (let ((path (org-element-property :path link)))
        (if (string= (file-name-extension path) "svg")
            (with-temp-buffer
              (insert-file-contents-literally path)
              (buffer-string))
          (org-md-link link desc info)))
    (org-md-link link desc info)))

(defun my-org-11ty-link (link desc info)
  (if (and (string= (org-element-property :type link) "file")
           (not (plist-get (org-export-read-attribute :attr_html (org-element-parent-element link))
                       :data-link)))
      (let ((path (org-element-property :path link)))
        (if (string= (file-name-extension path) "svg")
            (with-temp-buffer
              (insert-file-contents-literally path)
              (buffer-string))
          (org-11ty-link link desc info)))
    (org-11ty-link link desc info)))

(with-eval-after-load 'ox-html
  (setf
   (alist-get 'link (org-export-backend-transcoders (org-export-get-backend 'html)))
   'my-org-html-link))
(with-eval-after-load 'ox-md
  (setf
   (alist-get 'link (org-export-backend-transcoders (org-export-get-backend 'md)))
   'my-org-md-link))
(with-eval-after-load 'ox-11ty
  (setf
   (alist-get 'link (org-export-backend-transcoders (org-export-get-backend '11ty)))
   'my-org-11ty-link))

(defvar my-supernote-ip-address "192.168.1.221")
(defun my-supernote-get-exported-files ()
  (let ((data (plz 'get (format "http://%s:8089/EXPORT" my-supernote-ip-address)))
        (list))
    (when (string-match "const json = '\\(.*\\)'" data)
      (sort
       (alist-get 'fileList (json-parse-string (match-string 1 data) :object-type 'alist :array-type 'list))
       :key (lambda (o) (alist-get 'date o))
       :lessp 'string<
       :reverse t))))

(defun my-supernote-org-attach-latest-exported-file ()
  (interactive)
  ;; save the file to the screenshot directory
  (let ((info (car (my-supernote-get-exported-files)))
        new-file
        renamed)
    ;; delete matching files
    (setq new-file (expand-file-name
                    (replace-regexp-in-string " " "%20" (alist-get 'name info) (org-attach-dir))))
    (when (file-exists-p new-file)
      (delete-file new-file))
    (org-attach-attach
     (format "http://%s:8089%s" my-supernote-ip-address
             (alist-get 'uri info))
     nil
     'url)
    (setq new-file (my-latest-file (org-attach-dir)))
    ;; recolor
    (my-sketch-recolor-png new-file)
    ;; autocrop that image
    (my-image-autocrop new-file)
    ;; possibly rename
    (setq renamed (my-image-recognize-get-new-filename new-file))
    (when renamed
      (setq renamed (expand-file-name renamed (org-attach-dir)))
      (rename-file new-file renamed t)
      (my-image-store renamed) ; file it in my archive
      (setq new-file renamed))
    ;; use a sketch link if it has an ID
    (if (string-match "^[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]-[0-9][0-9] "
                      (file-name-base renamed))
        (org-insert-link nil (concat "sketchFull:" (file-name-base renamed)))
      ;; insert the link
      (org-insert-link nil (concat "attachment:" (replace-regexp-in-string "#" "%23" (file-name-nondirectory new-file)))))
    (org-redisplay-inline-images)))