#!/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)
             (cuirass utils)
             (ice-9 getopt-long))

(define* (show-help)
  (simple-format #t "Usage: ~a [OPTIONS] SPECFILE~%" (%program-name))
  (display "Run build jobs from SPECFILE.

      --one-shot            Evaluate and build jobs only once
      --cache-directory=DIR Use DIR for storing repository data
  -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
  '((one-shot                   (value #f))
    (cache-directory            (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 (fetch-repository spec)
  "Get the latest version of repository specified in SPEC.  Clone repository
if required."
  (let ((cachedir (%package-cachedir)))
    (or (file-exists? cachedir) (mkdir cachedir))
    (with-directory-excursion cachedir
      (let ((name   (job-spec-name spec))
            (url    (job-spec-url spec))
            (branch (job-spec-branch spec))
            (commit (job-spec-commit spec))
            (tag    (job-spec-tag spec)))
        (or (file-exists? name) (system* "git" "clone" url name))
        (with-directory-excursion name
          (and (zero? (system* "git" "fetch"))
               (zero? (system* "git" "reset" "--hard"
                               (or tag
                                   commit
                                   (string-append "origin/" branch))))))))))

(define (set-load-path! spec)
  "Set %LOAD-PATH to match what is specified in SPEC."
  (let* ((name (job-spec-name spec))
         (path (job-spec-load-path spec))
         (dir  (string-join (list (%package-cachedir) name path) "/")))
    (format #t "prepending ~s to the load path~%" dir)
    (set! %load-path (cons dir %load-path))))

(define (evaluate store db spec)
  "Evaluate and build package derivations.  Return a list a jobs."
  (let ((mod (make-user-module)))
    (save-module-excursion
     (λ ()
       (set-current-module mod)
       ;; Handle both relative and absolute file names for SPEC-FILE.
       (with-directory-excursion
           (string-append (%package-cachedir) "/" (job-spec-name spec))
         (primitive-load (job-spec-file spec)))))
    (let* ((proc (module-ref mod (job-spec-proc spec)))
           (jobs (proc store (job-spec-arguments spec))))
      (map (λ (job)
             (let ((id (db-add-evaluation db job)))
               (make-job #:name (job-name job)
                         #:derivation (job-derivation job)
                         #:metadata (acons 'id id (job-metadata job)))))
           jobs))))

(define (build-packages store db jobs)
  "Build JOBS which is a list of <job> objects."
  (let ((build-derivations (guix-variable 'derivations 'build-derivations))
        (current-build-output-port
         (guix-variable 'store 'current-build-output-port))
        (derivation-path->output-path
         (guix-variable 'derivations 'derivation-path->output-path)))
    (map (λ (job)
           (let ((log-port (tmpfile))
                 (name     (job-name job))
                 (drv      (job-derivation job)))
             (setvbuf log-port _IOLBF)
             (format #t "building ~A...~%" drv)
             (parameterize ((current-build-output-port log-port))
               (build-derivations store (list drv))
               (db-add-build-log db job log-port)
               (close-port log-port))
             (format #t "~A~%" (derivation-path->output-path drv))))
         jobs)))

(define (process-spec db spec)
  "Evaluate and build SPEC"
  (fetch-repository spec)
  (let ((old-path %load-path))
    (and (job-spec-load-path spec) (set-load-path! spec))
    (let ((store ((guix-variable 'store 'open-connection))))
      (dynamic-wind
        (const #t)
        (λ ()
          (let ((jobs (evaluate store db spec))
                (set-build-options
                 (guix-variable 'store 'set-build-options)))
            (set-build-options store #:use-substitutes? #f)
            (build-packages store db jobs)))
        (λ ()
          ((guix-variable 'store 'close-connection) store)
          (set! %load-path old-path))))))

(define (process-specs db jobspecs)
  "Evaluate and build JOBSPECS and store results in DB."
  (for-each (λ (spec) (process-spec db spec)) jobspecs))

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

(define* (main #:optional (args (command-line)))
  (let* ((opts     (getopt-long args %options))
         (specfile (option-ref opts '() '())))
    (parameterize
        ((%program-name     (car args))
         (%package-database (option-ref opts 'database (%package-database)))
         (%package-cachedir
          (option-ref opts 'cache-directory (%package-cachedir))))
      (cond
       ((option-ref opts 'help #f)
        (show-help)
        (exit 0))
       ((option-ref opts 'version #f)
        (show-version)
        (exit 0))
       ((null? specfile)
        (display "You must provide a specification file as argument.~%")
        (exit 1))
       (else
        (let ((one-shot? (option-ref opts 'one-shot #f))
              (interval  (string->number (option-ref opts 'interval "60")))
              (specs     (save-module-excursion
                          (λ ()
                            (set-current-module (make-user-module))
                            (primitive-load (car specfile))))))
          (with-database db
            (if one-shot?
                (process-specs db specs)
                (while #t
                  (process-specs db specs)
                  (sleep interval))))))))))