(require 'cl-lib)
(defun my-org-get-docinfo (info)
  (interactive)
  (save-excursion
    (progn
      (goto-char (point-min))
      (let ((docinfo (if (re-search-forward "^[ \t]*\\*[ \t]+DOCUMENT[ \t]+METADATA" (point-max) t)
                         (org-entry-properties (point) nil)
                       nil)))
        (add-to-list 'docinfo
                     (cons "AUTHOR"
                           (org-export-data (plist-get info :author) info)))
        (add-to-list 'docinfo
                     (cons "PROJECT"
                           (org-export-data (plist-get info :title) info)))
        docinfo))))


(defun my-org-get-table-name ()
  (save-excursion
    (if (re-search-backward "^[ \t]*#\\+NAME:[ \t]*\\([^ \t]*\\).*$")
        (match-string 1)
      "")))

(defvar orgtools-themes nil
  "all themes we supported")

(defun orgtools-register-theme (name func)
  "add a theme to our supported theme list"
  (unless orgtools-themes
    (advice-add 'org-latex-template :around #'orgtools-latex-template))
  (unless (assoc name orgtools-themes) 
    (add-to-list 'orgtools-themes (list name func))))

(defun orgtools-latex-template (orig-fun &rest args)
  (let* ((content (car  args))
         (info (car (cdr args)))
         (docinfo (my-org-get-docinfo info)))
    (let* ((theme (cdr (assoc "THEME" docinfo)))
           (func (let ((vx (assoc theme orgtools-themes)))
                   (if vx
                       (car (cdr vx))
                     #'(lambda (content info docinfo)
                         (list content info )))))) 
      (apply orig-fun (apply func (list content info docinfo))))))