;;; org-ics.el --- icsorg npm package wrapper        -*- lexical-binding: t; -*-

;; Copyright (C) 2023  

;; Author:  <bodicsek@nerdmail.co>
;; Keywords: calendar, extensions, processes

;; This program 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.

;; This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.

;;; Commentary:

;; This package wraps the icsorg npm package.
;; It provides an autoloaded org-ics-sync function that invokes icsorg with the configured
;; custom variables.
;; The result is a an org file that can be used in org-agenda.
;; The synchronization is one way: ics -> org.

;;; Code:

;;=============================== custom variables ==============================

(defgroup org-ics nil
  "org-ics functions and settings."
  :group 'external
  :tag "org-ics"
  :prefix "org-ics-")

(defcustom org-ics-executable (executable-find "icsorg")
  "The icsorg executable."
  :group 'org-ics
  :type 'string)

(defcustom org-ics-ics-file nil
  "The ics file that should be converted to org. It can be an url."
  :group 'org-ics
  :type 'string)

(defcustom org-ics-org-file nil
  "The org file that should be created from your `org-ics-ics-file'."
  :group 'org-ics
  :type 'string)

(defcustom org-ics-past 7
  "How far back in time (number of days) should we grab the calendar entries from `org-ics-ics-file'."
  :group 'org-ics
  :type 'natnum)

(defcustom org-ics-future 14
  "How far forward in time (number of days) should we grab the calendar entries from `org-ics-ics-file'."
  :group 'org-ics
  :type 'natnum)

;;=============================== commands ==============================

;;;###autoload
(defun org-ics-sync ()
  "Runs icsorg executable with the customized variables."
  (interactive)
  (let* ((ret (funcall 'org-ics--raw-run-icsorg
		       "-i" org-ics-ics-file
		       "-o" (expand-file-name org-ics-org-file)
		       "-p" (number-to-string org-ics-past)
		       "-f" (number-to-string org-ics-future)))
         (exit-code (nth 0 ret))
         (output (nth 1 ret)))
    (if (eq exit-code 0)
	output
      "org-ics-sync error")))

(defun org-ics--raw-run-icsorg (&rest args)
  "Run icsorg with ARGS.
Returns a list with the first element being the exit code and the
second element being the output."
  (with-temp-buffer
    (list (apply 'call-process org-ics-executable nil (current-buffer) nil args)
          (replace-regexp-in-string "\n$" "" (buffer-string)))))

(provide 'org-ics)
;;; org-ics.el ends here