;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2016 Jelle Licht <jlicht@fsfe.org>
;;; Copyright © 2019 Timothy Sample <samplet@ngyro.com>
;;; Copyright © 2021 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2021 Pierre Langlois <pierre.langlois@gmx.com>
;;; Copyright © 2021 Philip McGrath <philip@philipmcgrath.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 (guix build-system node)
  #:use-module (guix store)
  #:use-module (guix utils)
  #:use-module (guix packages)
  #:use-module (guix gexp)
  #:use-module (guix monads)
  #:use-module (guix search-paths)
  #:use-module (guix build-system)
  #:use-module (guix build-system gnu)
  #:use-module (guix build-system trivial)
  #:use-module ((guix licenses) #:prefix license:)
  #:export (%node-build-system-modules
            node-build
            node-build-system

            node-is-type-object
            node-trivial-package))

(define* (node-is-type-object type #:optional (type-exists? #t))
  "Helper for node packages replacement.  This is actual code factorized from
the packages it replaces, use with caution.  It doesn't apply to all
javascript types."
  (string-append
   "function(value) {"
   (if type-exists?
       (string-append
        "if (typeof value === '" (string-downcase type) "') {return true;} ")
       "")
   "if (value === null || typeof value !== 'object') {return false;}
  return Object.prototype.toString.call(value) === '[object " type "]';}"))

(define* (node-trivial-package node-name version replacement description
                               #:key (propagated-inputs '())
                               (mozilla-doclink #f)  ;maybe-string
                               (shams #f))
  "This helper makes it easy to replace a cumbersome npm package by the
underlying javascript code. This is also useful to cut down the Node
dependency tree for some cumbersome polyfills that all current web browsers
already support."
  (package
    (name (string-append "node-"
                         (string-join (string-split node-name #\.) "-")))
    (version (format #f "~a" version))
    (source #f)
    (build-system trivial-build-system)
    (arguments
     (list
      #:builder
      (with-imported-modules '((guix build utils))
        #~(begin
            (use-modules (guix build utils))
            (let ((dir (string-append #$output "/lib/node_modules/" #$node-name)))
              (mkdir-p dir)
              (with-output-to-file (string-append dir "/index.js")
                (lambda _
                  (format #t "module.exports = ~a\n" #$replacement)))
              (when #$shams
                (copy-file (string-append dir "/index.js")
                           (string-append dir "/shams.js")))
              (with-output-to-file (string-append dir "/package.json")
                (lambda _
                  (format #t "{\"name\":~s~a}\n" #$node-name
                          (if #$shams
                              "\
,\"exports\":{\".\":\"./index.js\",\"./shams\":\"./shams.js\"}"
                              "")))))))))
    (propagated-inputs propagated-inputs)
    (home-page
     (if mozilla-doclink
         (string-append
          "https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/"
          mozilla-doclink "#browser_compatibility")
         ""))
    (synopsis (string-append "Replacement for npm package " name))
    (description description)
    (license license:gpl3+)))

(define %node-build-system-modules
  ;; Build-side modules imported by default.
  `((guix build node-build-system)
    (guix build json)
    ,@%gnu-build-system-modules))

(define (default-node)
  "Return the default Node package."
  ;; Lazily resolve the binding to avoid a circular dependency.
  (let ((node (resolve-interface '(gnu packages node))))
    (module-ref node 'node-lts)))

(define* (lower name
                #:key source inputs native-inputs outputs system target
                (node (default-node))
                #:allow-other-keys
                #:rest arguments)
  "Return a bag for NAME."
  (define private-keywords
    '(#:target #:node #:inputs #:native-inputs))

  (and (not target)                    ;XXX: no cross-compilation
       (bag
         (name name)
         (system system)
         (host-inputs `(,@(if source
                              `(("source" ,source))
                              '())
                        ,@inputs
                        ;; Keep the standard inputs of 'gnu-build-system'.
                        ,@(standard-packages)))
         (build-inputs `(("node" ,node)
                         ;; Many packages with native addons need
                         ;; libuv headers. The libuv version must
                         ;; be exactly the same as for the node
                         ;; package we are adding implicitly,
                         ;; so we take care of adding libuv, too.
                         ("libuv" ,@(assoc-ref (package-inputs node) "libuv"))
                         ,@native-inputs))
         (outputs outputs)
         (build node-build)
         (arguments (strip-keyword-arguments private-keywords arguments)))))

(define* (node-build name inputs
                     #:key
                     source
                     (npm-flags ''())
                     (test-target "test")
                     (tests? #t)
                     (phases '%standard-phases)
                     (outputs '("out"))
                     (search-paths '())
                     (system (%current-system))
                     (guile #f)
                     (imported-modules %node-build-system-modules)
                     (modules '((guix build node-build-system)
                                (guix build utils))))
  "Build SOURCE using NODE and INPUTS."
  (define builder
    (with-imported-modules imported-modules
      #~(begin
          (use-modules #$@(sexp->gexp modules))
          (node-build #:name #$name
                      #:source #+source
                      #:system #$system
                      #:npm-flags #$npm-flags
                      #:test-target #$test-target
                      #:tests? #$tests?
                      #:phases #$phases
                      #:outputs #$(outputs->gexp outputs)
                      #:search-paths '#$(sexp->gexp
                                         (map search-path-specification->sexp
                                              search-paths))
                      #:inputs #$(input-tuples->gexp inputs)))))

  (mlet %store-monad ((guile (package->derivation (or guile (default-guile))
                                                  system #:graft? #f)))
    (gexp->derivation name builder
                      #:system system
                      #:guile-for-build guile)))

(define node-build-system
  (build-system
    (name 'node)
    (description "The Node build system")
    (lower lower)))