;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013 Cyril Roelandt <tipecaml@gmail.com>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix 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.
;;;
;;; GNU Guix 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 GNU Guix.  If not, see <http://www.gnu.org/licenses/>.

(define-module (gnu packages datefudge)
  #:use-module (guix licenses)
  #:use-module (guix packages)
  #:use-module (guix download)
  #:use-module (guix build-system gnu)
  #:use-module (gnu packages)
  #:use-module (gnu packages perl))

(define-public datefudge
  (package
    (name "datefudge")
    (version "1.18")
    (source (origin
             (method url-fetch)
             (uri (string-append
                   "http://ftp.de.debian.org/debian/pool/main/d/"
                   "datefudge/datefudge_" version ".tar.gz"))
             (sha256
              (base32
               "0g26mk6nxfpzlgfj08ig0na9zk03fgghqr86xp5mja2gyfh58s00"))))
    (build-system gnu-build-system)
    (arguments
     '(#:test-target "test"
       #:phases
        (alist-replace
         'configure
         (lambda* (#:key version outputs #:allow-other-keys #:rest args)
          (pk version outputs)
          (let* ((out (assoc-ref outputs "out"))
                 (version (substring out (+ 1 (string-index-right out #\-)))))
           ;; The version is retrieved using dpkg-parsechangelog, which is
           ;; not available in Guix.
           (substitute* "Makefile"
             (("^VERSION.*$") (string-append "VERSION=" version)))
           ;; We do not need to pass these flags to "install".
           (substitute* "Makefile"
             (("-o root -g root") "")) 
           ;; The prefix is hard-coded in the Makefile, we do not want that.
           (substitute* "Makefile"
             (("^prefix.*$") (string-append "prefix=" out "\n")))))
         %standard-phases)))
    (inputs `(("perl" ,perl))) ; Needed for the tests.
    (home-page "http://packages.qa.debian.org/d/datefudge.html")
    (synopsis "Fake the system date")
    (description
     "This program (and preload library) fakes the system date so that
 programs think the wall clock is ... different.

 The faking is not complete; timestamp on files are not affected in any
 way.

 This package is useful if you want to test the date handling of your
 programs without changing the system clock. Examples: Does it handle
 expired certificates correctly? Does it work on a leap day?")
    (license gpl2)))