;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2020 Brett Gilio <brettg@posteo.net>
;;;
;;; 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 mercury)
  #:use-module (guix download)
  #:use-module (guix git-download)
  #:use-module (guix packages)
  #:use-module (guix utils)
  #:use-module ((guix licenses) #:prefix license:)
  #:use-module (guix build-system gnu)
  #:use-module (gnu packages autotools)
  #:use-module (gnu packages bdw-gc)
  #:use-module (gnu packages readline)
  #:use-module (gnu packages texinfo)
  #:use-module (gnu packages flex)
  #:use-module (gnu packages shells)
  #:use-module (gnu packages bison)
  #:use-module (gnu packages pkg-config)
  #:use-module (ice-9 match)) ; match-lambda

;; NOTE: Package `mercury` requires a specific revision and fork of
;; upstream Boehm `libgc`. We use this method to obtain that fork
;; and patch it into `mercury` manually.
(define (bdwgc-mercury commit-bdwgc hash)
  (let ((commit commit-bdwgc))
    (package (inherit libgc)
             (source
              (origin
                (method git-fetch)
                (uri (git-reference
                      (url "https://github.com/Mercury-Language/bdwgc.git")
                      (commit commit)))
                (sha256 (base32 hash))))
             (native-inputs
              `(("autoconf" ,autoconf)
                ("automake" ,automake)
                ("libtool" ,libtool)
                ,@(package-native-inputs libgc))))))

(define-public mercury
  (package
    (name "mercury")
    (version "14.01.1")
    (source (origin
              (method url-fetch)
              (uri (string-append
                    "https://dl.mercurylang.org/release/mercury-srcdist-"
                    version ".tar.gz"))
              (sha256
               (base32
                "12z8qi3da8q50mcsjsy5bnr4ia6ny5lkxvzy01a3c9blgbgcpxwq"))))
    (build-system gnu-build-system)
    (arguments
     `(#:modules ((guix build gnu-build-system)
                  (guix build utils)
                  (ice-9 match))
       #:tests? #f ; TODO: tests are cryptic. Figure it out later.
       #:phases
       (modify-phases %standard-phases
         (add-after 'unpack 'patch
           (lambda _
             (substitute*
                 (list "Makefile"
                       "Mmakefile"
                       "scripts/mercury_update_interface.in"
                       "scripts/mercury_config.in"
                       "scripts/mmake.in"
                       "scripts/mmake.sh"
                       "scripts/Mmake.vars.in"
                       "scripts/mdb.in"
                       "scripts/rs6000_hack"
                       "scripts/fullarch"
                       "scripts/mmc.in"
                       "scripts/canonical_grade"
                       "scripts/mprof.in"
                       "scripts/gud.el"
                       "scripts/ml.in"
                       "scripts/canonical_grade.in"
                       "scripts/mdprof.in"
                       "scripts/vpath_find"
                       "scripts/mkfifo_using_mknod.in"
                       "scripts/prepare_install_dir.in"
                       "scripts/ml.sh"
                       "scripts/mprof_merge_runs"
                       "scripts/mtc"
                       "scripts/mgnuc.in"
                       "scripts/c2init.in"
                       "bindist/bindist.Makefile")
               (("/bin/sh") (which "sh"))
               (("/bin/pwd") (which "pwd"))
               (("/bin/rm") (which "rm")))
             #t))
         (add-after 'unpack 'replace-boehm-gc
           (lambda* (#:key inputs outputs #:allow-other-keys)
             (let ((out (assoc-ref outputs "out"))
                   (libgc (assoc-ref inputs "libgc"))
                   (unpack (assoc-ref %standard-phases 'unpack))
                   (patch-source-shebangs
                    (assoc-ref %standard-phases 'patch-source-shebangs)))
               (map (match-lambda
                      ((src orig-name new-name)
                       (with-directory-excursion "."
                         (apply unpack (list #:source src))
                         (apply patch-source-shebangs (list #:source src)))
                       (delete-file-recursively new-name)
                       (invoke "mv" orig-name new-name)))
                    `((,libgc "source/include/gc" "boehm_gc"))))
             #t)))))
    (native-inputs
     `(("texinfo" ,texinfo)
       ("flex" ,flex)
       ("tcsh", tcsh)
       ("bison" ,bison)
       ("readline" ,readline)
       ("libatomic-ops" ,libatomic-ops)
       ("libgc" ,(bdwgc-mercury
                  "5287fbab8a6f2284a12beeb9e3ba592301436b98"
                  "1crlw7zhjik39qdfqp5w317dskxdrklfw48g4jzrjzry12hkmq9y"))
       ("pkg-config" ,pkg-config)))
    (synopsis "A pure logic programming language")
    (description "Mercury is a logic/functional programming language which 
combines the clarity and expressiveness of declarative programming with advanced
static analysis and error detection features.  Its highly optimized execution 
algorithm delivers efficiency far in excess of existing logic programming 
systems, and close to conventional programming systems. Mercury addresses 
the problems of large-scale program development, allowing modularity, 
separate compilation, and numerous optimization/time trade-offs.")
    (home-page "https://mercurylang.org")
    (license license:gpl2)))

(define-public mercury-minimal
  (package (inherit mercury)
	   (name "mercury-minimal")
	   (build-system gnu-build-system)
	   (arguments
            (substitute-keyword-arguments (package-arguments mercury)
              ((#:configure-flags flags ''())
               `(list "--enable-minimal-install"))))
           (inputs
            `(("gcc-toolchain" ,gcc-toolchain)))
           (synopsis "A pure logic programming language (used only for
compiling packages dependent on base Mercury)")))