code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2019 Ludovic Courtès <ludo@gnu.org>
;;;
;;; 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 installer locale)
  #:use-module (gnu installer utils)
  #:use-module ((gnu build locale) #:select (normalize-codeset))
  #:use-module (guix records)
  #:use-module (json)
  #:use-module (srfi srfi-1)
  #:use-module (ice-9 match)
  #:use-module (ice-9 regex)
  #:export (locale-language
            locale-territory
            locale-codeset
            locale-modifier

            locale->locale-string
            supported-locales->locales

            iso639->iso639-languages
            language-code->language-name

            iso3166->iso3166-territories
            territory-code->territory-name

            locale->configuration))

;;;
;;; Locale.
;;;

;; A glibc locale string has the following format:
;; language[_territory[.codeset][@modifier]].
(define locale-regexp "^([^_@]+)(_([^\\.@]+))?(\\.([^@]+))?(@([^$]+))?$")

;; LOCALE will be better expressed in a (guix record) that in an association
;; list. However, loading large files containing records does not scale
;; well. The same thing goes for ISO639 and ISO3166 association lists used
;; later in this module.
(define (locale-language assoc)
  (assoc-ref assoc 'language))
(define (locale-territory assoc)
  (assoc-ref assoc 'territory))
(define (locale-codeset assoc)
  (assoc-ref assoc 'codeset))
(define (locale-modifier assoc)
  (assoc-ref assoc 'modifier))

(define* (locale-string->locale string #:optional codeset)
  "Return the locale association list built from the parsing of STRING and,
optionally, CODESET."
  (let ((matches (string-match locale-regexp string)))
    `((language  . ,(match:substring matches 1))
      (territory . ,(match:substring matches 3))
      (codeset   . ,(or codeset (match:substring matches 5)))
      (modifier  . ,(match:substring matches 7)))))

(define (locale->locale-string locale)
  "Reverse operation of locale-string->locale."
  (let ((language (locale-language locale))
        (territory (locale-territory locale))
        (codeset (locale-codeset locale))
        (modifier (locale-modifier locale)))
    (apply string-append
           `(,language
             ,@(if territory
                   `("_" ,territory)
                   '())
             ,@(if codeset
                   `("." ,(normalize-codeset codeset))
                   '())
             ,@(if modifier
                   `("@" ,modifier)
                   '())))))

(define (supported-locales->locales supported-locales)
  "Given SUPPORTED-LOCALES, a file produced by 'glibc-supported-locales',
return a list of locales where each locale is an alist."
  (map (match-lambda
         ((locale . codeset)
          (locale-string->locale locale codeset)))
       (call-with-input-file supported-locales read)))

;;;
;;; Language.
;;;

(define (iso639-language-alpha2 assoc)
  (assoc-ref assoc 'alpha2))

(define (iso639-language-alpha3 assoc)
  (assoc-ref assoc 'alpha3))

(define (iso639-language-name assoc)
  (assoc-ref assoc 'name))

(define (supported-locale? locales alpha2 alpha3)
  "Find a locale in LOCALES whose alpha2 field matches ALPHA-2 or alpha3 field
matches ALPHA-3. The ISO639 standard specifies that ALPHA-2 is optional. Thus,
if ALPHA-2 is #f, only consider ALPHA-3. Return #f if not matching locale was
found."
  (find (lambda (locale)
          (let ((language (locale-language locale)))
            (or (and=> alpha2
                       (lambda (code)
                         (string=? language code)))
                (string=? language alpha3))))
        locales))

(define (iso639->iso639-languages locales iso639-3 iso639-5)
  "Return a list of ISO639 association lists created from the parsing of
ISO639-3 and ISO639-5 files."
  (call-with-input-file iso639-3
    (lambda (port-iso639-3)
      (call-with-input-file iso639-5
        (lambda (port-iso639-5)
          (filter-map
           (lambda (hash)
             (let ((alpha2 (assoc-ref hash "alpha_2"))
                   (alpha3 (assoc-ref hash "alpha_3"))
                   (name   (assoc-ref hash "name")))
               (and (supported-locale? locales alpha2 alpha3)
                    `((alpha2 . ,alpha2)
                      (alpha3 . ,alpha3)
                      (name   . ,name)))))
           (append
            (vector->list
             (assoc-ref (json->scm port-iso639-3) "639-3"))
            (vector->list
             (assoc-ref (json->scm port-iso639-5) "639-5")))))))))

(define (language-code->language-name languages language-code)
  "Using LANGUAGES as a list of ISO639 association lists, return the language
name corresponding to the given LANGUAGE-CODE."
  (let ((iso639-language
         (find (lambda (language)
                 (or
                  (and=> (iso639-language-alpha2 language)
                         (lambda (alpha2)
                           (string=? alpha2 language-code)))
                  (string=? (iso639-language-alpha3 language)
                            language-code)))
               languages)))
    (iso639-language-name iso639-language)))

;;;
;;; Territory.
;;;

(define (iso3166-territory-alpha2 assoc)
  (assoc-ref assoc 'alpha2))

(define (iso3166-territory-alpha3 assoc)
  (assoc-ref assoc 'alpha3))

(define (iso3166-territory-name assoc)
  (assoc-ref assoc 'name))

(define (iso3166->iso3166-territories iso3166)
  "Return a list of ISO3166 association lists created from the parsing of
ISO3166 file."
  (call-with-input-file iso3166
    (lambda (port)
      (map (lambda (hash)
             `((alpha2 . ,(assoc-ref hash "alpha_2"))
               (alpha3 . ,(assoc-ref hash "alpha_3"))
               (name   . ,(assoc-ref hash "name"))))
           (vector->list
            (assoc-ref (json->scm port) "3166-1"))))))

(define (territory-code->territory-name territories territory-code)
  "Using TERRITORIES as a list of ISO3166 association lists return the
territory name corresponding to the given TERRITORY-CODE."
  (let ((iso3166-territory
         (find (lambda (territory)
                 (or
                  (and=> (iso3166-territory-alpha2 territory)
                         (lambda (alpha2)
                           (string=? alpha2 territory-code)))
                  (string=? (iso3166-territory-alpha3 territory)
                            territory-code)))
               territories)))
    (iso3166-territory-name iso3166-territory)))

;;;
;;; Configuration formatter.
;;;

(define (locale->configuration locale)
  "Return the configuration field for LOCALE."
  `((locale ,locale)))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018, 2020 Mathieu Othacehe <m.othacehe@gmail.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 (gnu installer newt)
  #:use-module (gnu installer record)
  #:use-module (gnu installer utils)
  #:use-module (gnu installer newt ethernet)
  #:use-module (gnu installer newt final)
  #:use-module (gnu installer newt parameters)
  #:use-module (gnu installer newt hostname)
  #:use-module (gnu installer newt keymap)
  #:use-module (gnu installer newt locale)
  #:use-module (gnu installer newt menu)
  #:use-module (gnu installer newt network)
  #:use-module (gnu installer newt page)
  #:use-module (gnu installer newt partition)
  #:use-module (gnu installer newt services)
  #:use-module (gnu installer newt timezone)
  #:use-module (gnu installer newt user)
  #:use-module (gnu installer newt utils)
  #:use-module (gnu installer newt welcome)
  #:use-module (gnu installer newt wifi)
  #:use-module (guix config)
  #:use-module (guix discovery)
  #:use-module (guix i18n)
  #:use-module (srfi srfi-26)
  #:use-module (newt)
  #:export (newt-installer))

(define (init)
  (newt-init)
  (clear-screen)
  (set-screen-size!)
  (push-help-line
   (format #f (G_ "Press <F1> for installation parameters."))))

(define (exit)
  (newt-finish)
  (clear-screen))

(define (exit-error file key args)
  (newt-set-color COLORSET-ROOT "white" "red")
  (let ((width (nearest-exact-integer
                (* (screen-columns) 0.8)))
        (height (nearest-exact-integer
                 (* (screen-rows) 0.7))))
    (run-file-textbox-page
     #:info-text (format #f (G_ "The installer has encountered an unexpected \
problem. The backtrace is displayed below. Please report it by email to \
<~a>.") %guix-bug-report-address)
     #:title (G_ "Unexpected problem")
     #:file file
     #:exit-button? #f
     #:info-textbox-width width
     #:file-textbox-width width
     #:file-textbox-height height))
  (newt-set-color COLORSET-ROOT "white" "blue")
  (newt-finish)
  (clear-screen))

(define (final-page result prev-steps)
  (run-final-page result prev-steps))

(define* (locale-page #:key
                      supported-locales
                      iso639-languages
                      iso3166-territories)
  (run-locale-page
   #:supported-locales supported-locales
   #:iso639-languages iso639-languages
   #:iso3166-territories iso3166-territories))

(define (timezone-page zonetab)
  (run-timezone-page zonetab))

(define (welcome-page logo)
  (run-welcome-page logo))

(define (menu-page steps)
  (run-menu-page steps))

(define* (keymap-page layouts context)
  (run-keymap-page layouts #:context context))

(define (network-page)
  (run-network-page))

(define (hostname-page)
  (run-hostname-page))

(define (user-page)
  (run-user-page))

(define (partition-page)
  (run-partioning-page))

(define (services-page)
  (run-services-page))

(define (parameters-menu menu-proc)
  (newt-set-help-callback menu-proc))

(define (parameters-page keyboard-layout-selection)
  (run-parameters-page keyboard-layout-selection))

(define newt-installer
  (installer
   (name 'newt)
   (init init)
   (exit exit)
   (exit-error exit-error)
   (final-page final-page)
   (keymap-page keymap-page)
   (locale-page locale-page)
   (menu-page menu-page)
   (network-page network-page)
   (timezone-page timezone-page)
   (hostname-page hostname-page)
   (user-page user-page)
   (partition-page partition-page)
   (services-page services-page)
   (welcome-page welcome-page)
   (parameters-menu parameters-menu)
   (parameters-page parameters-page)))

license: mit


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2019 Ludovic Courtès <ludo@gnu.org>
;;;
;;; 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 installer newt ethernet)
  #:use-module (gnu installer connman)
  #:use-module (gnu installer steps)
  #:use-module (gnu installer newt utils)
  #:use-module (gnu installer newt page)
  #:use-module (guix i18n)
  #:use-module (ice-9 format)
  #:use-module (ice-9 match)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-35)
  #:use-module (newt)
  #:export (run-ethernet-page))

(define (ethernet-services)
  "Return all the connman services of ethernet type."
  (let ((services (connman-services)))
    (filter (lambda (service)
              (and (string=? (service-type service) "ethernet")
                   (not (string-null? (service-name service)))))
            services)))

(define (ethernet-service->text service)
  "Return a string describing the given ethernet SERVICE."
  (let* ((name (service-name service))
         (path (service-path service))
         (full-name (string-append name "-" path))
         (state (service-state service))
         (connected? (or (string=? state "online")
                         (string=? state "ready"))))
    (format #f "~c ~a~%"
            (if connected? #\* #\ )
            full-name)))

(define (connect-ethernet-service service)
  "Connect to the given ethernet SERVICE. Display a connecting page while the
connection is pending."
  (let* ((service-name (service-name service))
         (form (draw-connecting-page service-name)))
    (connman-connect service)
    (destroy-form-and-pop form)
    service))

(define (run-ethernet-page)
  (match (ethernet-services)
    (()
     (run-error-page
      (G_ "No ethernet service available, please try again.")
      (G_ "No service"))
     (raise
      (condition
       (&installer-step-abort))))
    ((service)
     ;; Only one service is available so return it directly.
     service)
    ((services ...)
     (run-listbox-selection-page
      #:info-text (G_ "Please select an ethernet network.")
      #:title (G_ "Ethernet connection")
      #:listbox-items services
      #:listbox-item->text ethernet-service->text
      #:listbox-height (min (+ (length services) 2) 10)
      #:button-text (G_ "Exit")
      #:button-callback-procedure
      (lambda _
        (raise
         (condition
          (&installer-step-abort))))
      #:listbox-callback-procedure connect-ethernet-service))))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018, 2020 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2019, 2020 Ludovic Courtès <ludo@gnu.org>
;;;
;;; 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 installer newt final)
  #:use-module (gnu installer final)
  #:use-module (gnu installer parted)
  #:use-module (gnu installer steps)
  #:use-module (gnu installer utils)
  #:use-module (gnu installer newt page)
  #:use-module (gnu installer newt utils)
  #:use-module (guix i18n)
  #:use-module (guix colors)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-35)
  #:use-module (ice-9 match)
  #:use-module (newt)
  #:export (run-final-page))

(define* (strip-prefix file #:optional (prefix (%installer-target-dir)))
  "Strip PREFIX from FILE, if PREFIX actually is a prefix of FILE."
  (if (string-prefix? prefix file)
      (string-drop file (string-length prefix))
      file))

(define* (run-config-display-page #:key locale)
  (let ((width (%configuration-file-width))
        (height (nearest-exact-integer
                 (/ (screen-rows) 2))))
    (run-file-textbox-page
     #:info-text (format #f (G_ "\
We're now ready to proceed with the installation! \
A system configuration file has been generated, it is displayed below.  \
This file will be available as '~a' on the installed system.  \
The new system will be created from this file once you've pressed OK.  \
This will take a few minutes.")
                         (strip-prefix (%installer-configuration-file)))
     #:title (G_ "Configuration file")
     #:file (%installer-configuration-file)
     #:edit-button? #t
     #:editor-locale locale
     #:info-textbox-width width
     #:file-textbox-width width
     #:file-textbox-height height
     #:exit-button-callback-procedure
     (lambda ()
       (raise
        (condition
         (&installer-step-abort)))))))

(define (run-install-success-page)
  (match (current-clients)
    (()
     (message-window
      (G_ "Installation complete")
      (G_ "Reboot")
      (G_ "Congratulations!  Installation is now complete.  \
You may remove the device containing the installation image and \
press the button to reboot.")))
    (_
     ;; When there are clients connected, send them a message and keep going.
     (send-to-clients '(installation-complete))))

  ;; Return success so that the installer happily reboots.
  'success)

(define (run-install-failed-page)
  (match (current-clients)
    (()
     (match (choice-window
             (G_ "Installation failed")
             (G_ "Resume")
             (G_ "Restart the installer")
             (G_ "The final system installation step failed.  You can resume from \
a specific step, or restart the installer."))
       (1 (raise
           (condition
            (&installer-step-abort))))
       (2
        ;; Keep going, the installer will be restarted later on.
        #t)))
    (_
     (send-to-clients '(installation-failure))
     #t)))

(define* (run-install-shell locale
                            #:key (users '()))
  (clear-screen)
  (newt-suspend)
  (let ((install-ok? (install-system locale #:users users)))
    (newt-resume)
    install-ok?))

(define (run-final-page result prev-steps)
  (let* ((configuration   (format-configuration prev-steps result))
         (user-partitions (result-step result 'partition))
         (locale          (result-step result 'locale))
         (users           (result-step result 'user))
         (install-ok?
          (with-mounted-partitions
           user-partitions
           (configuration->file configuration)
           (run-config-display-page #:locale locale)
           (run-install-shell locale #:users users))))
    (if install-ok?
        (run-install-success-page)
        (run-install-failed-page))))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Mathieu Othacehe <m.othacehe@gmail.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 (gnu installer newt hostname)
  #:use-module (gnu installer newt page)
  #:use-module (guix i18n)
  #:export (run-hostname-page))

(define (run-hostname-page)
  (run-input-page (G_ "Please enter the system hostname.")
                  (G_ "Hostname")))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018, 2020 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2019 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2020 Florian Pelz <pelzflorian@pelzflorian.de>
;;;
;;; 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 installer newt keymap)
  #:use-module (gnu installer keymap)
  #:use-module (gnu installer steps)
  #:use-module (gnu installer newt page)
  #:use-module (guix i18n)
  #:use-module (guix records)
  #:use-module (newt)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-35)
  #:use-module (ice-9 i18n)
  #:use-module (ice-9 match)
  #:export (run-keymap-page
            keyboard-layout->configuration))

(define (run-layout-page layouts layout->text context)
  (let ((title (G_ "Layout")))
    (run-listbox-selection-page
     #:title title
     #:info-text
     (case context
       ((param) (G_ "Please choose your keyboard layout. \
It will only be used during the installation process. \
Non-Latin layouts can be toggled with Alt+Shift."))
       (else (G_ "Please choose your keyboard layout. \
It will be used during the install process, and for the installed system. \
Non-Latin layouts can be toggled with Alt+Shift. You can switch to a \
different layout at any time from the parameters menu.")))
     #:listbox-items layouts
     #:listbox-item->text layout->text
     #:sort-listbox-items? #f
     #:button-text
     (case context
       ((param) (G_ "Continue"))
       (else (G_ "Exit")))
     #:button-callback-procedure
     (case context
       ((param) (const #t))
       (else
        (lambda _
          (raise
           (condition
            (&installer-step-abort)))))))))

(define (run-variant-page variants variant->text)
  (let ((title (G_ "Variant")))
    (run-listbox-selection-page
     #:title title
     #:info-text (G_ "Please choose a variant for your keyboard layout.")
     #:listbox-items variants
     #:listbox-item->text variant->text
     #:sort-listbox-items? #f
     #:button-text (G_ "Back")
     #:button-callback-procedure
     (lambda _
       (raise
        (condition
         (&installer-step-abort)))))))

(define (sort-layouts layouts)
  "Sort LAYOUTS list by putting the US layout ahead and return it."
  (define (layout<? layout1 layout2)
    (let ((text1 (x11-keymap-layout-description layout1))
          (text2 (x11-keymap-layout-description layout2)))
      ;; XXX: We're calling 'gettext' more than once per item.
      (string-locale<? (gettext text1 "xkeyboard-config")
                       (gettext text2 "xkeyboard-config"))))

  (define preferred
    ;; Two-letter language tag for the preferred keyboard layout.
    (or (getenv "LANGUAGE") "us"))

  (call-with-values
      (lambda ()
        (partition
         (lambda (layout)
           ;; The 'synopsis' field is usually a language code (e.g., "en")
           ;; while the 'name' field is a country code (e.g., "us").
           (or (string=? (x11-keymap-layout-name layout) preferred)
               (string=? (x11-keymap-layout-synopsis layout) preferred)))
         layouts))
    (lambda (main others)
      (append (sort main layout<?)
              (sort others layout<?)))))

(define (add-empty-variant variants)
  "Prepend #f to VARIANTS so the user has the option to select no variant.
The resulting layout may be different from all other variants (e.g. for
Azerbaijani)."
  (cons #f variants))

(define (sort-variants variants)
  "Sort VARIANTS list by putting the international variant ahead and return it."
  (call-with-values
      (lambda ()
        (partition
         (lambda (variant)
           (and variant
                (let ((name (x11-keymap-variant-name variant)))
                  (string=? name "altgr-intl"))))
         variants))
    (cut append <> <>)))

(define %non-latin-layouts
  ;; List of keyboard layouts marked as $nonlatin in xkeyboard-config.
  ;; See comments in xkeyboard-config file /share/X11/xkb/rules/base.
  ;; We ignore layouts that support Latin input: "kr"
  '("am" "ara" "ben" "bd" "bg" "bt" "by" "cs" "deva" "ge" "gh"
    "gr" "guj" "guru" "il" "in" "ir" "iku" "jp" "kan" "kh"
    "la" "lao" "lk" "mk" "mm" "mn" "mv" "mal" "olck" "ori" "pk"
    "ru" "scc" "sy" "syr" "tel" "th" "tj" "tam" "ua" "uz"
    ;; The list from xkeyboard-config is incomplete.  Add more layouts when
    ;; noticed:
    "et" "kz"))

(define %non-latin-variants
  '("cyrillic"))

(define %latin-layout+variants
  ;; These layout+variant combinations are Latin after all.
  '(("ir" "ku")))

(define (toggleable-latin-layout layout variant)
  "If LAYOUT is a non-Latin layout, return a new combined layout,
a variant, and options that allow the user to switch between the
non-Latin and the Latin layout.  Otherwise, return LAYOUT, VARIANT,
and #f."
  (if (and (not (equal? variant "latin"))
           (not (member (list layout variant) %latin-layout+variants))
           (or (member layout %non-latin-layouts)
               (member variant %non-latin-variants)))
      (let ((latin-layout (if (equal? variant "azerty") "fr" "us")))
        (list
         (string-append layout "," latin-layout)
         ;; Comma to use variant only for non-Latin:
         (and variant (string-append variant ","))
         "grp:alt_shift_toggle"))
      (list layout variant #f)))

(define* (run-keymap-page layouts #:key (context #f))
  "Run a page asking the user to select a keyboard layout and variant. LAYOUTS
is a list of supported X11-KEYMAP-LAYOUT.  For non-Latin keyboard layouts, a
second layout and toggle options will be added automatically.  Return a list
of three elements, the names of the selected keyboard layout, variant and
options."
  (define keymap-steps
    (list
     (installer-step
      (id 'layout)
      (compute
       (lambda _
         (run-layout-page
          (sort-layouts layouts)
          (lambda (layout)
            (gettext (x11-keymap-layout-description layout)
                     "xkeyboard-config"))
          context))))
     ;; Propose the user to select a variant among those supported by the
     ;; previously selected layout.
     (installer-step
      (id 'variant)
      (compute
       (lambda (result _)
         (let* ((layout (result-step result 'layout))
                (variants (x11-keymap-layout-variants layout)))
           ;; Return #f if the layout does not have any variant.
           (and (not (null? variants))
                (run-variant-page
                 (sort-variants (add-empty-variant variants))
                 (lambda (variant)
                   (if variant
                       (gettext (x11-keymap-variant-description variant)
                                "xkeyboard-config")
                       ;; Text to opt for no variant at all:
                       (gettext (x11-keymap-layout-description layout)
                                "xkeyboard-config")))))))))))

  (define (format-result result)
    (let ((layout (x11-keymap-layout-name
                   (result-step result 'layout)))
          (variant (and=> (result-step result 'variant)
                          (lambda (variant)
                            (gettext (x11-keymap-variant-name variant)
                                     "xkeyboard-config")))))
      (toggleable-latin-layout layout variant)))
  (format-result
   (run-installer-steps #:steps keymap-steps)))

(define (keyboard-layout->configuration keymap)
  "Return the operating system configuration snippet to install KEYMAP."
  (match keymap
    ((name #f "grp:alt_shift_toggle")
     `((keyboard-layout (keyboard-layout ,name
                                         #:options '("grp:alt_shift_toggle")))))
    ((name #f _)
     `((keyboard-layout (keyboard-layout ,name))))
    ((name variant "grp:alt_shift_toggle")
     `((keyboard-layout (keyboard-layout ,name ,variant
                                         #:options '("grp:alt_shift_toggle")))))
    ((name variant _)
     `((keyboard-layout (keyboard-layout ,name ,variant))))))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2019 Ludovic Courtès <ludo@gnu.org>
;;;
;;; 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 installer newt locale)
  #:use-module (gnu installer locale)
  #:use-module (gnu installer steps)
  #:use-module (gnu installer newt page)
  #:use-module (guix i18n)
  #:use-module (newt)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-35)
  #:use-module (ice-9 match)
  #:export (run-locale-page))

(define (run-language-page languages language->text)
  (define result
    (run-listbox-selection-page
     #:title (G_ "Locale language")
     #:info-text (G_ "Choose the language to use for the \
installation process and for the installed system.")
     #:info-textbox-width 70
     #:listbox-items languages
     #:listbox-item->text language->text
     #:sort-listbox-items? #f
     #:button-text (G_ "Exit")
     #:button-callback-procedure
     (lambda _
       (raise
        (condition
         (&installer-step-abort))))))

  ;; Immediately install the chosen language so that the territory page that
  ;; comes after (optionally) is displayed in the chosen language.
  (setenv "LANGUAGE" result)

  result)

(define (run-territory-page territories territory->text)
  (let ((title (G_ "Locale location")))
    (run-listbox-selection-page
     #:title title
     #:info-text (G_ "Choose a territory for this language.")
     #:listbox-items territories
     #:listbox-item->text territory->text
     #:button-text (G_ "Back")
     #:button-callback-procedure
     (lambda _
       (raise
        (condition
         (&installer-step-abort)))))))

(define (run-codeset-page codesets)
  (let ((title (G_ "Locale codeset")))
    (run-listbox-selection-page
     #:title title
     #:info-text (G_ "Choose the locale encoding.")
     #:listbox-items codesets
     #:listbox-item->text identity
     #:listbox-default-item "UTF-8"
     #:button-text (G_ "Back")
     #:button-callback-procedure
     (lambda _
       (raise
        (condition
         (&installer-step-abort)))))))

(define (run-modifier-page modifiers modifier->text)
  (let ((title (G_ "Locale modifier")))
    (run-listbox-selection-page
     #:title title
     #:info-text (G_ "Choose your locale's modifier. The most frequent \
modifier is euro. It indicates that you want to use Euro as the currency \
symbol.")
     #:listbox-items modifiers
     #:listbox-item->text modifier->text
     #:button-text (G_ "Back")
     #:button-callback-procedure
     (lambda _
       (raise
        (condition
         (&installer-step-abort)))))))

(define* (run-locale-page #:key
                          supported-locales
                          iso639-languages
                          iso3166-territories)
  "Run a page asking the user to select a locale language and possibly
territory, codeset and modifier. Use SUPPORTED-LOCALES as the list of glibc
available locales. ISO639-LANGUAGES is an association list associating a
locale code to a locale name. ISO3166-TERRITORIES is an association list
associating a territory code with a territory name. The formated locale, under
glibc format is returned."

  (define (break-on-locale-found locales)
    "Raise the &installer-step-break condition if LOCALES contains exactly one
element."
    (and (= (length locales) 1)
         (raise
          (condition (&installer-step-break)))))

  (define (filter-locales locales result)
    "Filter the list of locale records LOCALES using the RESULT returned by
the installer-steps defined below."
    (filter
     (lambda (locale)
       (and-map identity
                `(,(string=? (locale-language locale)
                             (result-step result 'language))
                  ,@(if (result-step-done? result 'territory)
                        (list (equal? (locale-territory locale)
                                      (result-step result 'territory)))
                        '())
                  ,@(if (result-step-done? result 'codeset)
                        (list (equal? (locale-codeset locale)
                                      (result-step result 'codeset)))
                        '())
                  ,@(if (result-step-done? result 'modifier)
                        (list (equal? (locale-modifier locale)
                                      (result-step result 'modifier)))
                        '()))))
     locales))

  (define (result->locale-string locales result)
    "Supposing that LOCALES contains exactly one locale record, turn it into a
glibc locale string and return it."
    (match (filter-locales locales result)
      ((locale)
       (locale->locale-string locale))))

  (define (sort-languages languages)
    "Extract some languages from LANGUAGES list and place them ahead."
    (let* ((first-languages '("en"))
           (other-languages (lset-difference equal?
                                             languages
                                             first-languages)))
      `(,@first-languages ,@other-languages)))

  (define locale-steps
    (list
     (installer-step
      (id 'language)
      (compute
       (lambda _
         (run-language-page
          (sort-languages
           (delete-duplicates (map locale-language supported-locales)))
          (lambda (language)
            (let ((english (language-code->language-name iso639-languages
                                                         language)))
              (setenv "LANGUAGE" language)
              (let ((native (gettext english "iso_639-3")))
                (unsetenv "LANGUAGE")
                native)))))))
     (installer-step
      (id 'territory)
      (compute
       (lambda (result _)
         (let ((locales (filter-locales supported-locales result)))
           ;; Stop the process if the language returned by the previous step
           ;; is matching one and only one supported locale.
           (break-on-locale-found locales)

           ;; Otherwise, ask the user to select a territory among those
           ;; supported by the previously selected language.
           (run-territory-page
            (delete-duplicates (map locale-territory locales))
            (lambda (territory)
              (if territory
                  (let ((english (territory-code->territory-name
                                  iso3166-territories territory)))
                    (gettext english "iso_3166-1"))
                  (G_ "No location"))))))))
     (installer-step
      (id 'codeset)
      (compute
       (lambda (result _)
         (let ((locales (filter-locales supported-locales result)))
           ;; Same as above but we now have a language and a territory to
           ;; narrow down the search of a locale.
           (break-on-locale-found locales)

           ;; Otherwise, choose a codeset.
           (let ((codesets (delete-duplicates (map locale-codeset locales))))
             (if (member "UTF-8" codesets)
                 "UTF-8"                          ;don't even ask
                 (run-codeset-page codesets)))))))
     (installer-step
      (id 'modifier)
      (compute
       (lambda (result _)
         (let ((locales (filter-locales supported-locales result)))
           ;; Same thing with a language, a territory and a codeset this time.
           (break-on-locale-found locales)

           ;; Otherwise, ask for a modifier.
           (run-modifier-page
            (delete-duplicates (map locale-modifier locales))
            (lambda (modifier)
              (or modifier (G_ "No modifier"))))))))))

  ;; If run-installer-steps returns locally, it means that the user had to go
  ;; through all steps (language, territory, codeset and modifier) to select a
  ;; locale. In that case, like if we exited by raising &installer-step-break
  ;; condition, turn the result into a glibc locale string and return it.
  (result->locale-string
   supported-locales
   (run-installer-steps #:steps locale-steps)))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Mathieu Othacehe <m.othacehe@gmail.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 (gnu installer newt menu)
  #:use-module (gnu installer steps)
  #:use-module (gnu installer newt page)
  #:use-module (guix i18n)
  #:use-module (newt)
  #:export (run-menu-page))

(define (run-menu-page steps)
  "Run a menu page, asking the user to select where to resume the install
process from."
  (define (steps->items steps)
    (filter (lambda (step)
              (installer-step-description step))
            steps))

  (run-listbox-selection-page
   #:info-text (G_ "Choose where you want to resume the install.  \
You can also abort the installation by pressing the Abort button.")
   #:title (G_ "Installation menu")
   #:listbox-items (steps->items steps)
   #:listbox-item->text installer-step-description
   #:sort-listbox-items? #f
   #:button-text (G_ "Abort")
   #:button-callback-procedure (lambda ()
                                 (newt-finish)
                                 (primitive-exit 1))))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2019, 2020 Ludovic Courtès <ludo@gnu.org>
;;;
;;; 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 installer newt network)
  #:use-module (gnu installer connman)
  #:use-module (gnu installer steps)
  #:use-module (gnu installer utils)
  #:use-module (gnu installer newt ethernet)
  #:use-module (gnu installer newt page)
  #:use-module (gnu installer newt wifi)
  #:use-module (guix i18n)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-11)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-35)
  #:use-module (ice-9 match)
  #:use-module (newt)
  #:export (run-network-page))

;; Maximum length of a technology name.
(define technology-name-max-length (make-parameter 20))

(define (technology->text technology)
  "Return a string describing the given TECHNOLOGY."
  (let* ((name (technology-name technology))
         (padded-name (string-pad-right name
                                        (technology-name-max-length))))
    (format #f "~a~%" padded-name)))

(define (run-technology-page)
  "Run a page to ask the user which technology shall be used to access
Internet and return the selected technology. For now, only technologies with
\"ethernet\" or \"wifi\" types are supported."
  (define (technology-items)
    (filter (lambda (technology)
              (let ((type (technology-type technology)))
                (or
                 (string=? type "ethernet")
                 (string=? type "wifi"))))
            (connman-technologies)))

  (match (technology-items)
    (()
     (case (choice-window
            (G_ "Internet access")
            (G_ "Continue")
            (G_ "Exit")
            (G_ "The install process requires Internet access but no \
network devices were found. Do you want to continue anyway?"))
       ((1) (raise
             (condition
              (&installer-step-break))))
       ((2) (raise
             (condition
              (&installer-step-abort))))))
    ((technology)
     ;; Since there's only one technology available, skip the selection
     ;; screen.
     technology)
    ((items ...)
     (run-listbox-selection-page
      #:info-text (G_ "The install process requires Internet access.\
 Please select a network device.")
      #:title (G_ "Internet access")
      #:listbox-items items
      #:listbox-item->text technology->text
      #:listbox-height (min (+ (length items) 2) 10)
      #:button-text (G_ "Exit")
      #:button-callback-procedure
      (lambda _
        (raise
         (condition
          (&installer-step-abort))))))))

(define (find-technology-by-type technologies type)
  "Find and return a technology with the given TYPE in TECHNOLOGIES list."
  (find (lambda (technology)
          (string=? (technology-type technology)
                    type))
        technologies))

(define (wait-technology-powered technology)
  "Wait and display a progress bar until the given TECHNOLOGY is powered."
  (let ((name (technology-name technology))
        (full-value 5))
    (run-scale-page
     #:title (G_ "Powering technology")
     #:info-text (format #f (G_ "Waiting for technology ~a to be powered.")
                         name)
     #:scale-full-value full-value
     #:scale-update-proc
     (lambda (value)
       (let* ((technologies (connman-technologies))
              (type (technology-type technology))
              (updated-technology
               (find-technology-by-type technologies type))
              (technology-powered? updated-technology))
         (sleep 1)
         (if technology-powered?
             full-value
             (+ value 1)))))))

(define (wait-service-online)
  "Display a newt scale until connman detects an Internet access. Do
FULL-VALUE tentatives, spaced by 1 second."
  (define (online?)
    (or (connman-online?)
        (file-exists? "/tmp/installer-assume-online")))

  (let* ((full-value 5))
    (run-scale-page
     #:title (G_ "Checking connectivity")
     #:info-text (G_ "Waiting for Internet access establishment...")
     #:scale-full-value full-value
     #:scale-update-proc
     (lambda (value)
       (sleep 1)
       (if (online?)
           full-value
           (+ value 1))))
    (unless (online?)
      (run-error-page
       (G_ "The selected network does not provide access to the \
Internet, please try again.")
       (G_ "Connection error"))
      (raise
       (condition
        (&installer-step-abort))))))

(define (run-network-page)
  "Run a page to allow the user to configure connman so that it can access the
Internet."
  (define network-steps
    (list
     ;; Ask the user to choose between ethernet and wifi technologies.
     (installer-step
      (id 'select-technology)
      (compute
       (lambda _
         (run-technology-page))))
     ;; Enable the previously selected technology.
     (installer-step
      (id 'power-technology)
      (compute
       (lambda (result _)
         (let ((technology (result-step result 'select-technology)))
           (connman-enable-technology technology)
           (wait-technology-powered technology)))))
     ;; Propose the user to connect to one of the service available for the
     ;; previously selected technology.
     (installer-step
      (id 'connect-service)
      (compute
       (lambda (result _)
         (let* ((technology (result-step result 'select-technology))
                (type (technology-type technology)))
           (cond
            ((string=? "wifi" type)
             (run-wifi-page))
            ((string=? "ethernet" type)
             (run-ethernet-page)))))))
     ;; Wait for connman status to switch to 'online, which means it can
     ;; access Internet.
     (installer-step
      (id 'wait-online)
      (compute (lambda _
                 (wait-service-online))))))
  (run-installer-steps
   #:steps network-steps
   #:rewind-strategy 'start))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2019, 2020 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2019 Tobias Geerinckx-Rice <me@tobias.gr>
;;;
;;; 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 installer newt page)
  #:use-module (gnu installer steps)
  #:use-module (gnu installer utils)
  #:use-module (gnu installer newt utils)
  #:use-module (guix i18n)
  #:use-module (ice-9 i18n)
  #:use-module (ice-9 match)
  #:use-module (ice-9 receive)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-11)
  #:use-module (srfi srfi-26)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-35)
  #:use-module (newt)
  #:export (draw-info-page
            draw-connecting-page
            run-input-page
            run-error-page
            run-confirmation-page
            run-listbox-selection-page
            run-scale-page
            run-checkbox-tree-page
            run-file-textbox-page

            run-form-with-clients))

;;; Commentary:
;;;
;;; Some helpers around guile-newt to draw or run generic pages. The
;;; difference between 'draw' and 'run' terms comes from newt library. A page
;;; is drawn when the form it contains does not expect any user
;;; interaction. In that case, it is necessary to call (newt-refresh) to force
;;; the page to be displayed. When a form is 'run', it is blocked waiting for
;;; any action from the user (press a button, input some text, ...).
;;;
;;; Code:

(define* (watch-clients! form #:optional (clients (current-clients)))
  "Have FORM watch the file descriptors corresponding to current client
connections.  Consequently, FORM may exit with the 'exit-fd-ready' reason."
  (when (current-server-socket)
    (form-watch-fd form (fileno (current-server-socket))
                   FD-READ))

  (for-each (lambda (client)
              (form-watch-fd form (fileno client)
                             (logior FD-READ FD-EXCEPT)))
            clients))

(define close-port-and-reuse-fd
  (let ((bit-bucket #f))
    (lambda (port)
      "Close PORT and redirect its underlying FD to point to a valid open file
descriptor."
      (let ((fd (fileno port)))
        (unless bit-bucket
          (set! bit-bucket (car (pipe))))
        (close-port port)

        ;; FIXME: We're leaking FD.
        (dup2 (fileno bit-bucket) fd)))))

(define* (run-form-with-clients form exp)
  "Run FORM such as it watches the file descriptors beneath CLIENTS after
sending EXP to all the clients.

Automatically restart the form when it exits with 'exit-fd-ready but without
an actual client reply--e.g., it got a connection request or a client
disconnect.

Like 'run-form', return two values: the exit reason, and an \"argument\"."
  (define* (discard-client! port #:optional errno)
    (if errno
        (syslog "removing client ~d due to ~s~%"
                (fileno port) (strerror errno))
        (syslog "removing client ~d due to EOF~%"
                (fileno port)))

    ;; XXX: Watch out!  There's no 'form-unwatch-fd' procedure in Newt so we
    ;; cheat: we keep PORT's file descriptor open, but make it a duplicate of
    ;; a valid but inactive FD.  Failing to do that, 'run-form' would
    ;; select(2) on the now-closed port and keep spinning as select(2) returns
    ;; EBADF.
    (close-port-and-reuse-fd port)

    (current-clients (delq port (current-clients)))
    (close-port port))

  (define title
    ;; Title of FORM.
    (match exp
      (((? symbol? tag) alist ...)
       (match (assq 'title alist)
         ((_ title) title)
         (_         tag)))
      (((? symbol? tag) _ ...)
       tag)
      (_
       'unknown)))

  ;; Send EXP to all the currently-connected clients.
  (send-to-clients exp)

  (let loop ()
    (syslog "running form ~s (~s) with ~d clients~%"
            form title (length (current-clients)))

    ;; Call 'watch-clients!' within the loop because there might be new
    ;; clients.
    (watch-clients! form)

    (let-values (((reason argument) (run-form form)))
      (match reason
        ('exit-fd-ready
         (match (fdes->ports argument)
           ((port _ ...)
            (if (memq port (current-clients))

                ;; Read a reply from a client or handle its departure.
                (catch 'system-error
                  (lambda ()
                    (match (read port)
                      ((? eof-object? eof)
                       (discard-client! port)
                       (loop))
                      (obj
                       (syslog "form ~s (~s): client ~d replied ~s~%"
                               form title (fileno port) obj)
                       (values 'exit-fd-ready obj))))
                  (lambda args
                    (discard-client! port (system-error-errno args))
                    (loop)))

                ;; Accept a new client and send it EXP.
                (match (accept port)
                  ((client . _)
                   (syslog "accepting new client ~d while on form ~s~%"
                           (fileno client) form)
                   (catch 'system-error
                     (lambda ()
                       (write exp client)
                       (newline client)
                       (force-output client)
                       (current-clients (cons client (current-clients))))
                     (lambda _
                       (close-port client)))
                   (loop)))))))
        (_
         (values reason argument))))))

(define (draw-info-page text title)
  "Draw an informative page with the given TEXT as content.  Set the title of
this page to TITLE."
  (send-to-clients `(info (title ,title) (text ,text)))
  (let* ((text-box
          (make-reflowed-textbox -1 -1 text 40
                                 #:flags FLAG-BORDER))
         (grid (make-grid 1 1))
         (form (make-form)))
    (set-grid-field grid 0 0 GRID-ELEMENT-COMPONENT text-box)
    (add-component-to-form form text-box)
    (make-wrapped-grid-window grid title)
    (draw-form form)
    ;; This call is imperative, otherwise the form won't be displayed. See the
    ;; explanation in the above commentary.
    (newt-refresh)
    form))

(define (draw-connecting-page service-name)
  "Draw a page to indicate a connection in in progress."
  (draw-info-page
   (format #f (G_ "Connecting to ~a, please wait.") service-name)
   (G_ "Connection in progress")))

(define* (run-input-page text title
                         #:key
                         (allow-empty-input? #f)
                         (default-text #f)
                         (input-visibility-checkbox? #f)
                         (input-field-width 40)
                         (input-flags 0))
  "Run a page to prompt user for an input. The given TEXT will be displayed
above the input field. The page title is set to TITLE. Unless
allow-empty-input? is set to #t, an error page will be displayed if the user
enters an empty input.  INPUT-FLAGS is a bitwise-or'd set of flags for the
input box, such as FLAG-PASSWORD."
  (let* ((text-box
          (make-reflowed-textbox -1 -1 text
                                 input-field-width
                                 #:flags FLAG-BORDER))
         (input-visible-cb
          (make-checkbox -1 -1 (G_ "Show") #\space "x "))
         (input-flags* (if input-visibility-checkbox?
                           (logior FLAG-PASSWORD FLAG-SCROLL
                                   input-flags)
                           input-flags))
         (input-entry (make-entry -1 -1 20
                                  #:flags input-flags*))
         (ok-button (make-button -1 -1 (G_ "OK")))
         (grid (vertically-stacked-grid
                GRID-ELEMENT-COMPONENT text-box
                GRID-ELEMENT-SUBGRID
                (apply
                 horizontal-stacked-grid
                 GRID-ELEMENT-COMPONENT input-entry
                 `(,@(if input-visibility-checkbox?
                         (list GRID-ELEMENT-COMPONENT input-visible-cb)
                         '())))
                GRID-ELEMENT-COMPONENT ok-button))
         (form (make-form #:flags FLAG-NOF12)))

    (add-component-callback
     input-visible-cb
     (lambda ()
       (set-entry-flags input-entry
                        FLAG-PASSWORD
                        FLAG-ROLE-TOGGLE)))

    (when default-text
      (set-entry-text input-entry default-text))

    (add-form-to-grid grid form #t)
    (make-wrapped-grid-window grid title)
    (let ((error-page (lambda ()
                        (run-error-page (G_ "Please enter a non empty input.")
                                        (G_ "Empty input")))))
      (let loop ()
        (receive (exit-reason argument)
            (run-form-with-clients form
                                   `(input (title ,title) (text ,text)
                                           (default ,default-text)))
          (let ((input (if (eq? exit-reason 'exit-fd-ready)
                           argument
                           (entry-value input-entry))))
            (cond ((not input)                 ;client disconnect or something
                   (loop))
                  ((and (not allow-empty-input?)
                        (eq? exit-reason 'exit-component)
                        (string=? input ""))
                   ;; Display the error page.
                   (error-page)
                   ;; Set the focus back to the input input field.
                   (set-current-component form input-entry)
                   (loop))
                  (else
                   (destroy-form-and-pop form)
                   input))))))))

(define (run-error-page text title)
  "Run a page to inform the user of an error. The page contains the given TEXT
to explain the error and an \"OK\" button to acknowledge the error. The title
of the page is set to TITLE."
  (let* ((text-box
          (make-reflowed-textbox -1 -1 text 40
                                 #:flags FLAG-BORDER))
         (grid (make-grid 1 2))
         (ok-button (make-button -1 -1 "OK"))
         (form (make-form)))

    (set-grid-field grid 0 0 GRID-ELEMENT-COMPONENT text-box)
    (set-grid-field grid 0 1 GRID-ELEMENT-COMPONENT ok-button
                    #:pad-top 1)

    ;; Set the background color to red to indicate something went wrong.
    (newt-set-color COLORSET-ROOT "white" "red")
    (add-components-to-form form text-box ok-button)
    (make-wrapped-grid-window grid title)
    (run-form-with-clients form
                           `(error (title ,title) (text ,text)))
    ;; Restore the background to its original color.
    (newt-set-color COLORSET-ROOT "white" "blue")
    (destroy-form-and-pop form)))

(define* (run-confirmation-page text title
                                #:key (exit-button-procedure (const #f)))
  "Run a page to inform the user of an error. The page contains the given TEXT
to explain the error and an \"OK\" button to acknowledge the error. The title
of the page is set to TITLE."
  (let* ((text-box
          (make-reflowed-textbox -1 -1 text 40
                                 #:flags FLAG-BORDER))
         (ok-button (make-button -1 -1 (G_ "Continue")))
         (exit-button (make-button -1 -1 (G_ "Exit")))
         (grid (vertically-stacked-grid
                GRID-ELEMENT-COMPONENT text-box
                GRID-ELEMENT-SUBGRID
                (horizontal-stacked-grid
                 GRID-ELEMENT-COMPONENT ok-button
                 GRID-ELEMENT-COMPONENT exit-button)))
         (form (make-form #:flags FLAG-NOF12)))

    (add-form-to-grid grid form #t)
    (make-wrapped-grid-window grid title)

    (receive (exit-reason argument)
        (run-form-with-clients form
                               `(confirmation (title ,title)
                                              (text ,text)))
      (dynamic-wind
        (const #t)
        (lambda ()
          (match exit-reason
            ('exit-component
             (cond
              ((components=? argument ok-button)
               #t)
              ((components=? argument exit-button)
               (exit-button-procedure))))
            ('exit-fd-ready
             (if argument
                 #t
                 (exit-button-procedure)))))
        (lambda ()
          (destroy-form-and-pop form))))))

(define* (run-listbox-selection-page #:key
                                     info-text
                                     title
                                     (info-textbox-width 50)
                                     listbox-items
                                     listbox-item->text
                                     (listbox-height 20)
                                     (listbox-default-item #f)
                                     (listbox-allow-multiple? #f)
                                     (sort-listbox-items? #t)
                                     (allow-delete? #f)
                                     (skip-item-procedure?
                                      (const #f))
                                     button-text
                                     (button-callback-procedure
                                      (const #t))
                                     (button2-text #f)
                                     (button2-callback-procedure
                                      (const #t))
                                     (listbox-callback-procedure
                                      identity)
                                     (client-callback-procedure
                                      listbox-callback-procedure)
                                     (hotkey-callback-procedure
                                      (const #t)))
  "Run a page asking the user to select an item in a listbox. The page
contains, stacked vertically from the top to the bottom, an informative text
set to INFO-TEXT, a listbox and a button. The listbox will be filled with
LISTBOX-ITEMS converted to text by applying the procedure LISTBOX-ITEM->TEXT
on every item. The selected item from LISTBOX-ITEMS is returned. The button
text is set to BUTTON-TEXT and the procedure BUTTON-CALLBACK-PROCEDURE called
when it is pressed. The procedure LISTBOX-CALLBACK-PROCEDURE is called when an
item from the listbox is selected (by pressing the <ENTER> key).

INFO-TEXTBOX-WIDTH is the width of the textbox where INFO-TEXT will be
displayed. LISTBOX-HEIGHT is the height of the listbox.

If LISTBOX-DEFAULT-ITEM is set to the value of one of the items in
LISTBOX-ITEMS, it will be selected by default. Otherwise, the first element of
the listbox is selected.

If LISTBOX-ALLOW-MULTIPLE? is set to #t, multiple items from the listbox can
be selected (using the <SPACE> key). It that case, a list containing the
selected items will be returned.

If SORT-LISTBOX-ITEMS? is set to #t, the listbox items are sorted using
'string-locale<?' procedure (after being converted to text).

If ALLOW-DELETE? is #t, the form will return if the <DELETE> key is pressed,
otherwise nothing will happen.

Each time the listbox current item changes, call SKIP-ITEM-PROCEDURE? with the
current listbox item as argument. If it returns #t, skip the element and jump
to the next/previous one depending on the previous item, otherwise do
nothing."
  (let loop ()
    (define (fill-listbox listbox items)
      "Append the given ITEMS to LISTBOX, once they have been converted to text
with LISTBOX-ITEM->TEXT. Each item appended to the LISTBOX is given a key by
newt. Save this key by returning an association list under the form:

	((NEWT-LISTBOX-KEY . ITEM) ...)

where NEWT-LISTBOX-KEY is the key returned by APPEND-ENTRY-TO-LISTBOX, when
ITEM was inserted into LISTBOX."
      (map (lambda (item)
             (let* ((text (listbox-item->text item))
                    (key (append-entry-to-listbox listbox text)))
               (cons key item)))
           items))

    (define (sort-listbox-items listbox-items)
      "Return LISTBOX-ITEMS sorted using the 'string-locale<?' procedure on the text
corresponding to each item in the list."
      (let* ((items (map (lambda (item)
                           (cons item (listbox-item->text item)))
                         listbox-items))
             (sorted-items
              (sort items (lambda (a b)
                            (let ((text-a (cdr a))
                                  (text-b (cdr b)))
                              (string-locale<? text-a text-b))))))
        (map car sorted-items)))

    ;; Store the last selected listbox item's key.
    (define last-listbox-key (make-parameter #f))

    (define (previous-key keys key)
      (let ((index (list-index (cut eq? key <>) keys)))
        (and index
             (> index 0)
             (list-ref keys (- index 1)))))

    (define (next-key keys key)
      (let ((index (list-index (cut eq? key <>) keys)))
        (and index
             (< index (- (length keys) 1))
             (list-ref keys (+ index 1)))))

    (define (set-default-item listbox listbox-keys default-item)
      "Set the default item of LISTBOX to DEFAULT-ITEM. LISTBOX-KEYS is the
association list returned by the FILL-LISTBOX procedure. It is used because
the current listbox item has to be selected by key."
      (for-each (match-lambda
                  ((key . item)
                   (when (equal? item default-item)
                     (set-current-listbox-entry-by-key listbox key))))
                listbox-keys))

    (let* ((listbox (make-listbox
                     -1 -1
                     listbox-height
                     (logior FLAG-SCROLL FLAG-BORDER FLAG-RETURNEXIT
                             (if listbox-allow-multiple?
                                 FLAG-MULTIPLE
                                 0))))
           (form (make-form #:flags FLAG-NOF12))
           (info-textbox
            (make-reflowed-textbox -1 -1 info-text
                                   info-textbox-width
                                   #:flags FLAG-BORDER))
           (button (make-button -1 -1 button-text))
           (button2 (and button2-text
                         (make-button -1 -1 button2-text)))
           (grid (vertically-stacked-grid
                  GRID-ELEMENT-COMPONENT info-textbox
                  GRID-ELEMENT-COMPONENT listbox
                  GRID-ELEMENT-SUBGRID
                  (apply
                   horizontal-stacked-grid
                   GRID-ELEMENT-COMPONENT button
                   `(,@(if button2
                           (list GRID-ELEMENT-COMPONENT button2)
                           '())))))
           (sorted-items (if sort-listbox-items?
                             (sort-listbox-items listbox-items)
                             listbox-items))
           (keys (fill-listbox listbox sorted-items)))

      (define (choice->item str)
        ;; Return the item that corresponds to STR.
        (match (find (match-lambda
                       ((key . item)
                        (string=? str (listbox-item->text item))))
                     keys)
          ((key . item) item)
          (#f (raise (condition (&installer-step-abort))))))

      ;; On every listbox element change, check if we need to skip it. If yes,
      ;; depending on the 'last-listbox-key', jump forward or backward. If no,
      ;; do nothing.
      (add-component-callback
       listbox
       (lambda ()
         (let* ((current-key (current-listbox-entry listbox))
                (listbox-keys (map car keys))
                (last-key (last-listbox-key))
                (item (assoc-ref keys current-key))
                (prev-key (previous-key listbox-keys current-key))
                (next-key (next-key listbox-keys current-key)))
           ;; Update last-listbox-key before a potential call to
           ;; set-current-listbox-entry-by-key, because it will immediately
           ;; cause this callback to be called for the new entry.
           (last-listbox-key current-key)
           (when (skip-item-procedure? item)
             (when (eq? prev-key last-key)
               (if next-key
                   (set-current-listbox-entry-by-key listbox next-key)
                   (set-current-listbox-entry-by-key listbox prev-key)))
             (when (eq? next-key last-key)
               (if prev-key
                   (set-current-listbox-entry-by-key listbox prev-key)
                   (set-current-listbox-entry-by-key listbox next-key)))))))

      (when listbox-default-item
        (set-default-item listbox keys listbox-default-item))

      (when allow-delete?
        (form-add-hotkey form KEY-DELETE))

      (add-form-to-grid grid form #t)
      (make-wrapped-grid-window grid title)

      (receive (exit-reason argument)
          (run-form-with-clients form
                                 `(list-selection (title ,title)
                                                  (multiple-choices?
                                                   ,listbox-allow-multiple?)
                                                  (items
                                                   ,(map listbox-item->text
                                                         listbox-items))))
        (dynamic-wind
          (const #t)
          (lambda ()
            (match exit-reason
              ('exit-component
               (cond
                ((components=? argument button)
                 (button-callback-procedure))
                ((and button2
                      (components=? argument button2))
                 (button2-callback-procedure))
                ((components=? argument listbox)
                 (if listbox-allow-multiple?
                     (let* ((entries (listbox-selection listbox))
                            (items (map (lambda (entry)
                                          (assoc-ref keys entry))
                                        entries)))
                       (listbox-callback-procedure items))
                     (let* ((entry (current-listbox-entry listbox))
                            (item (assoc-ref keys entry)))
                       (listbox-callback-procedure item))))))
              ('exit-fd-ready
               (let* ((choice argument)
                      (item   (if listbox-allow-multiple?
                                  (map choice->item choice)
                                  (choice->item choice))))
                 (client-callback-procedure item)))
              ('exit-hotkey
               (let* ((entry (current-listbox-entry listbox))
                      (item (assoc-ref keys entry)))
                 (hotkey-callback-procedure argument item)))))
          (lambda ()
            (destroy-form-and-pop form)))))))

(define* (run-scale-page #:key
                         title
                         info-text
                         (info-textbox-width 50)
                         (scale-width 40)
                         (scale-full-value 100)
                         scale-update-proc
                         (max-scale-update 5))
  "Run a page with a progress bar (called 'scale' in newt). The given
INFO-TEXT is displayed in a textbox above the scale. The width of the textbox
is set to INFO-TEXTBOX-WIDTH. The width of the scale is set to
SCALE-WIDTH. SCALE-FULL-VALUE indicates the value that correspond to 100% of
the scale.

The procedure SCALE-UPDATE-PROC shall return a new scale
value. SCALE-UPDATE-PROC will be called until the returned value is superior
or equal to SCALE-FULL-VALUE, but no more than MAX-SCALE-UPDATE times. An
error is raised if the MAX-SCALE-UPDATE limit is reached."
  (let* ((info-textbox
          (make-reflowed-textbox -1 -1 info-text
                                 info-textbox-width
                                 #:flags FLAG-BORDER))
         (scale (make-scale -1 -1 scale-width scale-full-value))
         (grid (vertically-stacked-grid
                GRID-ELEMENT-COMPONENT info-textbox
                GRID-ELEMENT-COMPONENT scale))
         (form (make-form)))

    (add-form-to-grid grid form #t)
    (make-wrapped-grid-window grid title)

    (draw-form form)
    ;; This call is imperative, otherwise the form won't be displayed. See the
    ;; explanation in the above commentary.
    (newt-refresh)

    (dynamic-wind
      (const #t)
      (lambda ()
        (let loop ((i max-scale-update)
                   (last-value 0))
          (let ((value (scale-update-proc last-value)))
            (set-scale-value scale value)
            ;; Same as above.
            (newt-refresh)
            (unless (>= value scale-full-value)
              (if (> i 0)
                  (loop (- i 1) value)
                  (error "Max scale updates reached."))))))
      (lambda ()
        (destroy-form-and-pop form)))))

(define %none-selected
  (circular-list #f))

(define* (run-checkbox-tree-page #:key
                                 info-text
                                 title
                                 items
                                 (selection %none-selected)
                                 item->text
                                 (info-textbox-width 50)
                                 (checkbox-tree-height 10)
                                 (ok-button-callback-procedure
                                  (const #t))
                                 (exit-button-callback-procedure
                                  (const #t)))
  "Run a page allowing the user to select one or multiple items among ITEMS in
a checkbox list. The page contains vertically stacked from the top to the
bottom, an informative text set to INFO-TEXT, the checkbox list and two
buttons, 'Ok' and 'Exit'. The page title's is set to TITLE. ITEMS are
converted to text using ITEM->TEXT before being displayed in the checkbox
list.  SELECTION is a list of Booleans of the same length as ITEMS that
specifies which items are initially checked.

INFO-TEXTBOX-WIDTH is the width of the textbox where INFO-TEXT will be
displayed. CHECKBOX-TREE-HEIGHT is the height of the checkbox list.

OK-BUTTON-CALLBACK-PROCEDURE is called when the 'Ok' button is pressed.
EXIT-BUTTON-CALLBACK-PROCEDURE is called when the 'Exit' button is
pressed.

This procedure returns the list of checked items in the checkbox list among
ITEMS when 'Ok' is pressed."
  (define (fill-checkbox-tree checkbox-tree items)
    (map (lambda (item selected?)
           (let* ((item-text (item->text item))
                  (key (add-entry-to-checkboxtree checkbox-tree item-text
                                                  (if selected?
                                                      FLAG-SELECTED
                                                      0))))
             (cons key item)))
         items
         selection))

  (let loop ()
    (let* ((checkbox-tree
            (make-checkboxtree -1 -1
                               checkbox-tree-height
                               FLAG-BORDER))
           (info-textbox
            (make-reflowed-textbox -1 -1 info-text
                                   info-textbox-width
                                   #:flags FLAG-BORDER))
           (ok-button (make-button -1 -1 (G_ "OK")))
           (exit-button (make-button -1 -1 (G_ "Exit")))
           (grid (vertically-stacked-grid
                  GRID-ELEMENT-COMPONENT info-textbox
                  GRID-ELEMENT-COMPONENT checkbox-tree
                  GRID-ELEMENT-SUBGRID
                  (horizontal-stacked-grid
                   GRID-ELEMENT-COMPONENT ok-button
                   GRID-ELEMENT-COMPONENT exit-button)))
           (keys (fill-checkbox-tree checkbox-tree items))
           (form (make-form #:flags FLAG-NOF12)))

      (define (choice->item str)
        ;; Return the item that corresponds to STR.
        (match (find (match-lambda
                       ((key . item)
                        (string=? str (item->text item))))
                     keys)
          ((key . item) item)
          (#f (raise (condition (&installer-step-abort))))))

      (add-form-to-grid grid form #t)
      (make-wrapped-grid-window grid title)

      (receive (exit-reason argument)
          (run-form-with-clients form
                                 `(checkbox-list (title ,title)
                                                 (text ,info-text)
                                                 (items
                                                  ,(map item->text items))))
        (dynamic-wind
          (const #t)

          (lambda ()
            (match exit-reason
              ('exit-component
               (cond
                ((components=? argument ok-button)
                 (let* ((entries (current-checkbox-selection checkbox-tree))
                        (current-items (map (lambda (entry)
                                              (assoc-ref keys entry))
                                            entries)))
                   (ok-button-callback-procedure)
                   current-items))
                ((components=? argument exit-button)
                 (exit-button-callback-procedure))))
              ('exit-fd-ready
               (map choice->item argument))))
          (lambda ()
            (destroy-form-and-pop form)))))))

(define* (edit-file file #:key locale)
  "Spawn an editor for FILE."
  (clear-screen)
  (newt-suspend)
  ;; Use Nano because it syntax-highlights Scheme by default.
  ;; TODO: Add a menu to choose an editor?
  (run-command (list "/run/current-system/profile/bin/nano" file)
               #:locale locale)
  (newt-resume))

(define* (run-file-textbox-page #:key
                                info-text
                                title
                                file
                                (info-textbox-width 50)
                                (file-textbox-width 50)
                                (file-textbox-height 30)
                                (exit-button? #t)
                                (edit-button? #f)
                                (editor-locale #f)
                                (ok-button-callback-procedure
                                 (const #t))
                                (exit-button-callback-procedure
                                 (const #t)))
  (let loop ()
    (let* ((info-textbox
            (make-reflowed-textbox -1 -1 info-text
                                   info-textbox-width
                                   #:flags FLAG-BORDER))
           (file-textbox
            (make-textbox -1 -1
                          file-textbox-width
                          file-textbox-height
                          (logior FLAG-SCROLL FLAG-BORDER)))
           (ok-button (make-button -1 -1 (G_ "OK")))
           (exit-button (make-button -1 -1 (G_ "Exit")))
           (edit-button (and edit-button?
                             (make-button -1 -1 (G_ "Edit"))))
           (grid (vertically-stacked-grid
                  GRID-ELEMENT-COMPONENT info-textbox
                  GRID-ELEMENT-COMPONENT file-textbox
                  GRID-ELEMENT-SUBGRID
                  (apply
                   horizontal-stacked-grid
                   GRID-ELEMENT-COMPONENT ok-button
                   `(,@(if edit-button?
                           (list GRID-ELEMENT-COMPONENT edit-button)
                           '())
                     ,@(if exit-button?
                           (list GRID-ELEMENT-COMPONENT exit-button)
                           '())))))
           (form (make-form #:flags FLAG-NOF12)))

      (add-form-to-grid grid form #t)
      (make-wrapped-grid-window grid title)

      (set-textbox-text file-textbox
                        (receive (_w _h text)
                            (reflow-text (read-all file)
                                         file-textbox-width
                                         0 0)
                          text))

      (receive (exit-reason argument)
          (run-form-with-clients form
                                 `(file-dialog (title ,title)
                                               (text ,info-text)
                                               (file ,file)))
        (define result
          (dynamic-wind
            (const #t)
            (lambda ()
              (match exit-reason
                ('exit-component
                 (cond
                  ((components=? argument ok-button)
                   (ok-button-callback-procedure))
                  ((and exit-button?
                        (components=? argument exit-button))
                   (exit-button-callback-procedure))
                  ((and edit-button?
                        (components=? argument edit-button))
                   (edit-file file))))
                ('exit-fd-ready
                 (if argument
                     (ok-button-callback-procedure)
                     (exit-button-callback-procedure)))))
            (lambda ()
              (destroy-form-and-pop form))))

        (if (and (eq? exit-reason 'exit-component)
                 (components=? argument edit-button))
            (loop)                                ;recurse in tail position
            result)))))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2020 Mathieu Othacehe <m.othacehe@gmail.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 (gnu installer newt parameters)
  #:use-module (gnu installer proxy)
  #:use-module (gnu installer steps)
  #:use-module (gnu installer newt page)
  #:use-module (guix i18n)
  #:use-module (ice-9 match)
  #:use-module (newt)
  #:export (run-parameters-page))

(define (run-proxy-page)
  (define proxy
    (run-input-page (G_ "Please enter the HTTP proxy URL. If you enter an \
empty string, proxy usage will be disabled.")
                    (G_ "HTTP proxy configuration")
                    #:allow-empty-input? #t))
  (if (string=? proxy "")
      (clear-http-proxy)
      (set-http-proxy proxy)))

(define (run-parameters-page keyboard-layout-selection)
  "Run a parameters page allowing to change the keyboard layout"
  (let* ((items
          (list
           (cons (G_ "Change keyboard layout") keyboard-layout-selection)
           (cons (G_ "Configure HTTP proxy") run-proxy-page)))
         (result
          (run-listbox-selection-page
           #:info-text (G_ "Please choose one of the following parameters or \
press ‘Back’ to go back to the installation process.")
           #:title (G_ "Installation parameters")
           #:listbox-items items
           #:listbox-item->text car
           #:sort-listbox-items? #f
           #:listbox-height 6
           #:button-text (G_ "Back"))))
    (match result
      ((_ . proc)
       (proc))
      (_ #f))))