;;; Whispers --- Stealth VPN and ssh tunneler
;;; Copyright © 2024 Runciter <runciter@whispers-vpn.org>
;;;
;;; This file is part of Whispers.
;;;
;;; Whispers 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.
;;;
;;; Whispers 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 Whispers.  If not, see <http://www.gnu.org/licenses/>.

(define-module (whispers)
  #:export (whispers))

(define herd-path "/run/current-system/profile/bin/herd")

(define (strip-final-slash path)
  "Strip the last character of the string PATH if it is a slash, and return
the resulting string."
  (let ((lgth (string-length path)))
    (if (equal? "/" (substring path (- lgth 1) lgth))
        (substring path 0 (- lgth 1))
        path)))

(define* (whispers #:key
                   (lieutenant "/")
                   (act '("status")))
  "Call an herd sub-process to command the whispers lieutenant at the
whispers path LIEUTENANT to perform the shepherd action described by the
list of strings ACT of the form either (ACTION) or (ACTION SERVICE
. ARGS), in which ARGS is optionally the emtpy list."
  (let ((lieut (strip-final-slash lieutenant)))
    (apply system*
           (append (list herd-path
                         "-s"
                         (string-append "/run/whispers"
                                        lieut
                                        "/unix-sockets/"
                                        (basename (string-append "/whispers"
                                                                 lieut))
                                        ".sock"))
                           act))))