#!/bin/sh
# -*- scheme -*-
exec ${GUILE:-@GUILE@} --no-auto-compile -e main -s "$0" "$@"
!#
;;;; cuirass - continuous integration system
;;;
;;; Copyright © 2016 Mathieu Lirzin <mthl@gnu.org>
;;;
;;; This file is part of Cuirass.
;;;
;;; Cuirass 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.
;;;
;;; Cuirass 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 Cuirass.  If not, see <http://www.gnu.org/licenses/>.

(use-modules (cuirass config)
             (cuirass base)
             (cuirass database)
             (cuirass job)
             (cuirass ui)
             (ice-9 getopt-long)
             (ice-9 match))

(define* (show-help prog)
  (simple-format #t "Usage: ~a [OPTIONS] [CACHEDIR]" prog)
  (display "
Run Guix job from a git repository cloned in CACHEDIR.

  -f  --use-file=FILE       Use FILE which defines the job to evaluate
  -D  --database=DB         Use DB to store build results.
  -I, --interval=N          Wait N seconds between each evaluation
  -V, --version             Display version
  -h, --help                Display this help message")
  (newline)
  (show-package-information))

(define %options
  `((file     (single-char #\f) (value #t))
    (database (single-char #\f) (value #t))
    (interval (single-char #\I) (value #t))
    (version  (single-char #\V) (value #f))
    (help     (single-char #\h) (value #f))))

(define %user-module
  ;; Cuirass user module.
  (let ((m (make-module)))
    (beautify-user-module! m)
    m))

(define (fetch-repository cachedir spec)
  "Get the latest version of Guix repository.  Clone repository in directory
DIR if required."
  (or (file-exists? cachedir) (mkdir cachedir))
  (with-directory-excursion cachedir
    (match spec
      (($ <job-spec> name url branch)
       (or (file-exists? name) (system* "git" "clone" url name))
       (with-directory-excursion name
         (and (zero? (system* "git" "fetch"))
              (zero? (system* "git" "reset" "--hard"
                              (string-append "origin/" branch)))))))))

(define (evaluate store db cachedir spec)
  "Evaluate and build package derivations.  Return a list a jobs."
  (save-module-excursion
   (lambda ()
     (set-current-module %user-module)
     (let ((dir (string-append cachedir "/" (job-spec-name spec))))
       (format #t "prepending ~s to the load path~%" dir)
       (set! %load-path (cons dir %load-path)))
     (primitive-load (job-spec-file spec))))
  (let* ((proc (module-ref %user-module (job-spec-proc spec)))
         (jobs (proc store (job-spec-arguments spec))))
    (for-each (λ (job) (db-add-evaluation db job))
              jobs)
    jobs))

(define (build-packages store jobs)
  "Build JOBS which is a list of <job> objects."
  (map (match-lambda
         (($ <job> name drv)
          (format #t "building ~A...~%" drv)
          ((guix-variable 'derivations 'build-derivations)
           store (list drv))
          (format #t "~A~%"
                  ((guix-variable 'derivations
                                  'derivation-path->output-path) drv))))
       jobs))


;;;
;;; Entry point.
;;;

(define* (main #:optional (args (command-line)))
  (let ((opts     (getopt-long args %options))
        (progname "cuirass"))
    (cond
     ((option-ref opts 'help #f)
      (show-help progname)
      (exit 0))
     ((option-ref opts 'version #f)
      (show-version progname)
      (exit 0))
     (else
      (let* ((specfile (option-ref opts 'file "tests/hello-subset.scm"))
             (dbfile   (option-ref opts 'database %package-database))
             (specs    (primitive-load specfile))
             (args     (option-ref opts '() #f))
             (cachedir (if (null? args)
                           (getenv "CUIRASS_CACHEDIR")
                           (car args))))
        (db-close (db-init dbfile))
        (while #t
          (for-each
           (λ (spec)
             (fetch-repository cachedir spec)
             (let ((store ((guix-variable 'store 'open-connection)))
                   (db    (db-open dbfile)))
               (dynamic-wind
                 (const #t)
                 (lambda ()
                   (let* ((jobs (evaluate store db cachedir spec))
                          (set-build-options
                           (guix-variable 'store 'set-build-options)))
                     (set-build-options store #:use-substitutes? #f)
                     (build-packages store jobs)))
                 (lambda ()
                   ((guix-variable 'store 'close-connection) store)
                   (db-close db)))))
           specs)
          (sleep (string->number (option-ref opts 'interval "60")))))))))