;;; ein-skewer.el --- Cell module

;; (C) 2016 - John M Miller

;; Author: John M Miller <millejoh at mac.com>

;; This file is NOT part of GNU Emacs.

;; ein-skewer.el 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.

;; ein-skewre.el 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 ein-cell.el.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;; This depends on the skewer package, so likely will get split into
;; its own package at some point.

;;; Code:

(require 'skewer-mode)

(defvar *ein:skewer-running-p* nil "True if the emacs httpd server has been started.")

(defun ein:js-prepare-result (result type)
  (list :output_type type :text result))

(defun ein:update-javascript-output (cell json result)
  (let ((val (ein:js-prepare-result
              (cdr (assoc 'value result))
              (plist-get json :output_type))))
    (setf (slot-value cell 'outputs) (list val))
    (ein:cell-append-display-data cell val)))

;; Format of result is ((id . STR) (type . STR) (status . STR) (value . STR) (time . FLOAT))
(defun ein:execute-javascript (cell json)
  (unless *ein:skewer-running-p*
    (run-skewer)
    (setq *ein:skewer-running-p* t))
  ;; Call synchronously is a bit dangerous here - we should maybe come up with a timeout
  ;; check.
  ;; (skewer-eval (plist-get json :javascript)
  ;;              (apply-partially #'ein:update-javascript-output cell json))
  (ein:update-javascript-output cell
                                json
                                (skewer-eval-synchronously (plist-get json :javascript)))
  )

(provide 'ein-skewer)