(use-modules
  ((guix licenses) #:prefix license:)
  (guix packages)
  (guix download)
  (guix git-download)
  (guix build-system ruby)
  (guix build-system trivial)
  (guix utils)
  (gnu packages bash)
  (gnu packages ruby)
  (ice-9 rdelim)
  (ice-9 popen))

(define ruby-ast-2.4.2-bootstrap
  (package
    (inherit ruby-ast)
    (version "2.4.2")
    (source
      (origin
        (method url-fetch)
        (uri (rubygems-uri "ast" version))
        (sha256
          (base32 "04nc8x27hlzlrr5c2gn7mar4vdr0apw5xg22wp6m8dx3wqr04a0y"))))
    (arguments
     `(#:tests? #f))))

(define ruby-ast-2.4.2
  (package
    (inherit ruby-ast-2.4.2-bootstrap)
    (arguments
     `(#:tests? #f
       ,@(substitute-keyword-arguments (package-arguments ruby-ast)
           ((#:phases phases)
            `(modify-phases ,phases
               (add-after 'unpack 'rld
                 (lambda _
                   (apply invoke "rld" "-ip." (find-files "." "\\.(rb|ru)$"))))
               (delete 'remove-coveralls-requirement)
               (delete 'remove-unnecessary-requirements))))))
    (native-inputs
      `(("rld" ,rld-bootstrap)
        ,@(package-native-inputs ruby-ast)))))

(define ruby-parser-with-rld
  ((package-input-rewriting `((,ruby-ast . ,ruby-ast-2.4.2)))
  (package
    (inherit ruby-parser)
    (arguments
     `(#:tests? #f
       #:phases
         (modify-phases %standard-phases
            (add-after 'unpack 'rld
              (lambda* (#:key inputs #:allow-other-keys)
                (apply invoke ; We can't use the wrapped bootstrap rld or it sets a GEM_PATH for a different ast gem
                  (string-append (assoc-ref inputs "ruby2.7") "/bin/ruby") "-Ilib"
                  (string-append (assoc-ref inputs "rld") "/bin/.rld-real") "-ip."
                  ; gauntlet_parser can only be used if gauntlet is present, but we
                  ; don't want to require it, so do not link to it
                  (delete "./lib/gauntlet_parser.rb" (find-files "." "\\.(rb|ru)$"))))))))
    (native-inputs
      `(("rld" ,rld-bootstrap)
         ("ruby2.7" ,ruby-2.7)
        ,@(package-native-inputs ruby-parser))))))

;;;;

(define %source-dir (dirname (current-filename)))
(define %git-dir (string-append %source-dir "/.git"))
(define %module (current-module))

; Bake a template by eval'ing the leaves
(define (bake tmpl)
 (cons
  (car tmpl)
  (map
   (lambda (x) (list (car x) (eval (cadr x) %module)))
   (cdr tmpl))))

(define rld-template
  '(package
    (name "rld")
    (version (read-line (open-pipe* OPEN_READ "git" "--git-dir" %git-dir "describe" "--always" "--dirty")))
    (source
     `(origin
       (method git-fetch)
       (uri (git-reference
             (recursive? #t)
             (url "https://git.singpolyma.net/rld")
             (commit ,(read-line (open-pipe* OPEN_READ "git" "--git-dir" %git-dir "rev-parse" "HEAD")))))
       (file-name (git-file-name name version))
       (sha256
        (base32
         ,(read-line (open-pipe* OPEN_READ "guix" "hash" "-rx" %source-dir))))))
    (build-system 'trivial-build-system)
    (arguments
      '`(#:modules ((guix build utils))
         #:builder
          (let* ((bindir (string-append (assoc-ref %outputs "out") "/bin"))
                 (outbin (string-append bindir "/rld")))
            (use-modules (guix build utils))
            (mkdir-p bindir)
            (set-path-environment-variable "PATH" '("bin")
                                           (list
                                             (assoc-ref %build-inputs "ruby"))
                                           #:separator ":")
            (set-path-environment-variable "GEM_PATH" '("lib/ruby/vendor_ruby")
                                           (list
                                             (assoc-ref %build-inputs "ruby-parser")
                                             (assoc-ref %build-inputs "ruby-ast"))
                                           #:separator ":")
            (chdir (assoc-ref %build-inputs "source"))
            (invoke "ruby" "bin/rld" "-p." "-o" outbin "bin/rld")
				(patch-shebang outbin)
            (chmod outbin #o755))))
    (inputs
      '`(("ruby" ,ruby-2.7)
         ("ruby-parser" ,ruby-parser-with-rld)))
    (synopsis "Linker for Ruby")
    (description "")
    (home-page "https://git.singpolyma.net/rld")
    (license 'license:agpl3)))

(define rld-bootstrap
  (package
    (inherit (eval (bake rld-template) %module))
    (version "bootstrap-be3900")
    (source
     (origin
       (method git-fetch)
       (uri (git-reference
             (recursive? #t)
             (url "https://git.singpolyma.net/rld")
             (commit "be390053302623e569164b2eaf5297fabd0bcd47")))
       (file-name (git-file-name "rld" "be3900"))
       (sha256
        (base32 "06878bywadm57l5w2sni40gmrwv87d2i4fj5c2axp0vsqvsz3q38"))))
    (inputs
      `(("bash" ,bash-minimal)
        ("ruby" ,ruby-2.7)
        ("ruby-parser" ,((package-input-rewriting `((,ruby-ast . ,ruby-ast-2.4.2-bootstrap))) ruby-parser))))
    (arguments
      '(#:modules ((guix build utils))
         #:builder
          (let* ((bindir (string-append (assoc-ref %outputs "out") "/bin"))
                 (outbin (string-append bindir "/rld")))
            (use-modules (guix build utils))
            (set-path-environment-variable "PATH" '("bin")
                                           (list
                                             (assoc-ref %build-inputs "ruby")
                                             (assoc-ref %build-inputs "bash"))
                                           #:separator ":")
            (set-path-environment-variable "GEM_PATH" '("lib/ruby/vendor_ruby")
                                           (list
                                             (assoc-ref %build-inputs "ruby-parser")
                                             (assoc-ref %build-inputs "ruby-ast"))
                                           #:separator ":")
            (chdir (assoc-ref %build-inputs "source"))
            (install-file "bin/rld" bindir)
				(patch-shebang outbin)
            (wrap-program outbin `("GEM_PATH" ":" prefix (,(getenv "GEM_PATH")))))))))

(eval (bake rld-template) %module)