;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2023 Nicolas Graves <ngraves@ngraves.fr>
;;;
;;; 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 import juliahub)
  #:use-module (ice-9 textual-ports)
  #:use-module (ice-9 regex)
  #:use-module (ice-9 match)
  #:use-module (ice-9 streams)
  #:use-module (ice-9 string-fun)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-9)
  #:use-module (srfi srfi-11)
  #:use-module (guix http-client)
  #:use-module (guix import utils)
  #:use-module (guix import json)
  #:use-module (guix base32)
  #:use-module (guix packages)
  #:use-module (guix upstream)
  #:use-module (json)
  #:use-module ((guix licenses) #:prefix license:)

  #:export (juliahub->guix-package
            %juliahub-updater
            juliahub-recursive-import))

;; To update, see file sysimg.jl
(define %julia-stdlibs
  (list "julia"
        "ArgTools"
        "Artifacts"
        "Base64"
        "CRC32c"
        "FileWatching"
        "Libdl"
        "Logging"
        "Mmap"
        "NetworkOptions"
        "SHA"
        "Serialization"
        "Sockets"
        "Unicode"
        "DelimitedFiles"
        "LinearAlgebra"
        "Markdown"
        "Printf"
        "Random"
        "Tar"
        "Dates"
        "Distributed"
        "Future"
        "InteractiveUtils"
        "LibGit2"
        "Profile"
        "SparseArrays"
        "UUIDs"
        "REPL"
        "SharedArrays"
        "Statistics"
        "SuiteSparse"
        "TOML"
        "Test"
        "LibCURL"
        "Downloads"
        "Pkg"
        "LazyArtifacts"))

(define (juliahub-uri name)
  (let* ((url (string-append "https://docs.juliahub.com/" name "/"))
         (port (http-fetch url #:text? #t))
         (_ (get-line port))
         (meta (get-line port))
         (regex "url=[a-zA-Z0-9]{5}\\/[0-9\\.]*")
         (redirect (match:substring (string-match regex meta))))
    (close-port port)
    (string-drop redirect 4)))

(define (juliahub-url name)
  (let* ((url (string-append "https://docs.juliahub.com/" name "/"))
         (uri (juliahub-uri name)))
    (string-append url uri "/")))

(define (juliahub-slug-version name)
  (let* ((uri (juliahub-uri name))
         (slug (string-take uri 5))
         (latest-version (string-drop uri 6)))
    `(,slug ,latest-version)))

(define (json->juliahub-direct-dependencies vector)
  (if (vector? vector)
      (filter-map
       (lambda (el)
         (let ((dep (json->juliahub-dependency el)))
           (if (and (juliahub-dependency-direct? dep)
                    (not (member (juliahub-dependency-name dep)
                                 %julia-stdlibs)))
               dep
               #f)))
       (vector->list vector))))

(define (json->juliahub-indirect-dependencies vector)
  (if (vector? vector)
      (filter-map
       (lambda (el)
         (let ((dep (json->juliahub-dependency el)))
           (if (and (not (juliahub-dependency-direct? dep))
                    (not (member (juliahub-dependency-name dep)
                                 %julia-stdlibs)))
               dep
               #f)))
       (vector->list vector))))

(define (ini-list->extra-dependencies lst)
  (match lst
    (('(extras) ooo ...)
     (extra-list->extra-dependencies ooo))
    (((tag) ooo ...)
     (ini-list->extra-dependencies ooo))
    ((attribute '= value ooo ...)
     (ini-list->extra-dependencies ooo))
    ('()
     '())))

(define (extra-list->extra-dependencies lst)
  (match lst
    ((attribute '= value ooo ...)
     `(,(symbol->string attribute) ,@(extra-list->extra-dependencies ooo)))
    (((tag) ooo ...)
     '())
    ('()
     '())))

(define (parse-extra-dependencies directory)
  (let* ((port (open-input-file (string-append directory "/Project.toml")))
         (ini-list (stream->list (port->stream port read))))
    (close-port port)
    (ini-list->extra-dependencies ini-list)))

;; Julia package.
(define-json-mapping <juliahub-package> make-juliahub-package juliahub-package?
  json->juliahub-package
  (homepage juliahub-package-homepage) ;string
  (readme juliahub-package-readme) ;string
  (version juliahub-package-version) ;string
  (description juliahub-package-description) ;string
  (direct-dependencies
   juliahub-package-direct-dependencies "deps"
   json->juliahub-direct-dependencies) ;list of <juliahub-dependency>
  (indirect-dependencies
   juliahub-package-indirect-dependencies "deps"
   json->juliahub-indirect-dependencies) ;list of <juliahub-dependency>
  (url juliahub-package-url) ;string
  (uuid juliahub-package-uuid) ;string
  (license juliahub-package-license)) ;string

(define-json-mapping <juliahub-dependency>
  make-juliahub-dependency juliahub-dependency?
  json->juliahub-dependency
  (direct? juliahub-dependency-direct? "direct") ;boolean
  (name juliahub-dependency-name) ;string
  (uuid juliahub-dependency-uuid) ;string
  (versions juliahub-dependency-versions "versions" vector->list)) ;list of strings

(define (julia-name->guix-name name)
  (string-append "julia-" (snake-case name)))

(define* (juliahub-fetch name #:key (version #f))
  "Return a <juliahub-package> record for package NAME, or #f on failure."
  (and=> (json-fetch (string-append (juliahub-url name) "pkg.json"))
         json->juliahub-package))

(define (make-julia-sexp name source home-page synopsis description
                         direct-dependencies test-dependencies-names licenses)
  "Return the `package' s-expression for a Julia package with the given NAME,
VERSION, URI, HASH, HOME-PAGE, DESCRIPTION, DEPENDENCIES,
TEST-DEPENDENCIES-NAMES and LICENSES."
  `(package
     (name ,(julia-name->guix-name name))
     (version ,version)
     (source ,source)
     (build-system julia-build-system)
     ,@(if (null? direct-dependencies)
           '()
           `((propagated-inputs
              (list ,@(map (compose julia-name->guix-name juliahub-dependency-name)
                           direct-dependencies)))))
     ,@(if (null? test-dependencies-names)
           '()
           `((native-inputs
              (list ,@(map julia-name->guix-name test-dependencies-names)))))
     (synopsis ,synopsis)
     (description ,description)
     (home-page ,home-page)
     (license ,(match licenses
                 (() #f)
                 ((license) (license->symbol license))
                 (_ `(list ,@(map license->symbol licenses)))))))

(define* (juliahub->guix-package package-name
                                 #:key version #:allow-other-keys)
  "Fetch the metadata for PACKAGE-NAME from juliahub.org, and return the
`package' s-expression corresponding to that package, or #f on failure.
Optionally include a VERSION string to fetch a specific version juliahub."
  (let ((package (if version
                     (juliahub-fetch package-name version)
                     (juliahub-fetch package-name))))
    (if package
        (let-values (((source directory)
                      (git->origin+dir
                       (juliahub-package-url package)
                       `(tag-or-commit
                         . ,(string-append
                             "v" (juliahub-package-version package))))))
          (let* ((dependencies-names
                  (map juliahub-dependency-name
                       (juliahub-package-direct-dependencies package)))
                 (licenses
                  (map spdx-string->license
                       (list (juliahub-package-license package))))
                 (test-dependencies-names (parse-extra-dependencies directory)))
            (values (make-julia-sexp
                     package-name
                     source
                     (juliahub-package-homepage package)
                     (juliahub-package-description package)
                     (beautify-description (juliahub-package-readme package))
                     (juliahub-package-direct-dependencies package)
                     test-dependencies-names
                     licenses)
                    (append dependencies-names test-dependencies-names))))
        (values #f '()))))

(define (guix-package->juliahub-name package)
  (let* ((url (juliahub-package-url package))
         (git-name (car (last-pair (string-split url #\/))))
         (ungitted-name (if (string-suffix? ".git" git-name)
                            (string-drop-right git-name 4)
                            git-name))
         (package-name (if (string-suffix? ".jl" ungitted-name)
                            (string-drop-right ungitted-name 4)
                            ungitted-name)))
    package-name))

(define* (import-release package #:key (version #f))
  "Return an <upstream-source> for the latest release of PACKAGE."
  (let* ((package-name (guix-package->juliahub-name package))
         (package      (juliahub-fetch package-name))
         (version  (or version (juliahub-package-version package))))
    (upstream-source
     (package (package-name package))
     (version version)
     (urls (list (juliahub-package-url package))))))

(define %juliahub-updater
  (upstream-updater
   (name 'juliahub)
   (description "Updater for Juliahub packages")
   (pred juliahub-package?)
   (import import-release)))

(define* (juliahub-recursive-import package-name #:optional version)
  (recursive-import package-name
                    #:repo '()
                    #:repo->guix-package juliahub->guix-package
                    #:guix-name julia-name->guix-name
                    #:version version))