;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2017 David Craven <david@craven.ch>
;;; Copyright © 2017, 2020, 2022 Mathieu Othacehe <othacehe@gnu.org>
;;; Copyright © 2017 Leo Famulari <leo@famulari.name>
;;; Copyright © 2019, 2021, 2023 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2020 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
;;; Copyright © 2022 Josselin Poiret <dev@jpoiret.xyz>
;;; Copyright © 2022 Reza Alizadeh Majd <r.majd@pantherx.org>
;;; Copyright © 2024 Tomas Volf <~@wolfsden.cz>
;;;
;;; 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 bootloader)
  #:use-module (gnu system file-systems)
  #:use-module (gnu system uuid)
  #:use-module (guix discovery)
  #:use-module (guix gexp)
  #:use-module (guix profiles)
  #:use-module (guix records)
  #:use-module (guix deprecation)
  #:use-module (guix diagnostics)
  #:use-module (guix i18n)
  #:use-module (guix modules)
  #: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 (menu-entry
            menu-entry?
            menu-entry-label
            menu-entry-device
            menu-entry-linux
            menu-entry-linux-arguments
            menu-entry-initrd
            menu-entry-device-mount-point
            menu-entry-multiboot-kernel
            menu-entry-multiboot-arguments
            menu-entry-multiboot-modules
            menu-entry-chain-loader

            menu-entry->sexp
            sexp->menu-entry

            bootloader
            bootloader?
            bootloader-name
            bootloader-package
            bootloader-installer
            bootloader-disk-image-installer
            bootloader-configuration-file
            bootloader-configuration-file-generator

            <bootloader-target>
            bootloader-target
            bootloader-target?
            bootloader-target-type
            bootloader-target-expected?
            bootloader-target-path
            bootloader-target-offset
            bootloader-target-device
            bootloader-target-file-system
            bootloader-target-label
            bootloader-target-uuid

            target-error?
            target-error-type
            target-error-targets

            gbegin
            :path :devpath :device :fs :label :uuid
            with-targets

            bootloader-configuration
            bootloader-configuration?
            bootloader-configuration-bootloader
            bootloader-configuration-target ;deprecated
            bootloader-configuration-targets
            bootloader-configuration-menu-entries
            bootloader-configuration-default-entry
            bootloader-configuration-timeout
            bootloader-configuration-keyboard-layout
            bootloader-configuration-theme
            bootloader-configuration-terminal-outputs
            bootloader-configuration-terminal-inputs
            bootloader-configuration-serial-unit
            bootloader-configuration-serial-speed
            bootloader-configuration-device-tree-support?
            bootloader-configuration-extra-initrd

            %bootloaders
            lookup-bootloader-by-name

            efi-bootloader-chain))

\f
;;;
;;; Menu-entry record.
;;;

(define-record-type* <menu-entry>
  menu-entry make-menu-entry
  menu-entry?
  (label           menu-entry-label)
  (device          menu-entry-device       ; file system uuid, label, or #f
                   (default #f))
  (device-mount-point menu-entry-device-mount-point
                   (default #f))
  (linux           menu-entry-linux
                   (default #f))
  (linux-arguments menu-entry-linux-arguments
                   (default '()))          ; list of string-valued gexps
  (initrd          menu-entry-initrd       ; file name of the initrd as a gexp
                   (default #f))
  (multiboot-kernel menu-entry-multiboot-kernel
                    (default #f))
  (multiboot-arguments menu-entry-multiboot-arguments
                       (default '()))      ; list of string-valued gexps
  (multiboot-modules menu-entry-multiboot-modules
                     (default '()))        ; list of multiboot commands, where
                                           ; a command is a list of <string>
  (chain-loader     menu-entry-chain-loader
                    (default #f)))         ; string, path of efi file

(define (report-menu-entry-error menu-entry)
  (raise
   (condition
    (&message
     (message
      (format #f (G_ "invalid menu-entry: ~a") menu-entry)))
    (&fix-hint
     (hint
      (G_ "Please chose only one of:
@enumerate
@item direct boot by specifying fields @code{linux},
@code{linux-arguments} and @code{linux-modules},
@item multiboot by specifying fields @code{multiboot-kernel},
@code{multiboot-arguments} and @code{multiboot-modules},
@item chain-loader by specifying field @code{chain-loader}.
@end enumerate"))))))

(define (menu-entry->sexp entry)
  "Return ENTRY serialized as an sexp."
  (define (device->sexp device)
    (match device
      ((? uuid? uuid)
       `(uuid ,(uuid-type uuid) ,(uuid->string uuid)))
      ((? file-system-label? label)
       `(label ,(file-system-label->string label)))
      (_ device)))
  (match entry
    (($ <menu-entry> label device mount-point
                     (? identity linux) linux-arguments (? identity initrd)
                     #f () () #f)
     `(menu-entry (version 0)
                  (label ,label)
                  (device ,(device->sexp device))
                  (device-mount-point ,mount-point)
                  (linux ,linux)
                  (linux-arguments ,linux-arguments)
                  (initrd ,initrd)))
    (($ <menu-entry> label device mount-point #f () #f
                     (? identity multiboot-kernel) multiboot-arguments
                     multiboot-modules #f)
     `(menu-entry (version 0)
                  (label ,label)
                  (device ,(device->sexp device))
                  (device-mount-point ,mount-point)
                  (multiboot-kernel ,multiboot-kernel)
                  (multiboot-arguments ,multiboot-arguments)
                  (multiboot-modules ,multiboot-modules)))
    (($ <menu-entry> label device mount-point #f () #f #f () ()
                     (? identity chain-loader))
     `(menu-entry (version 0)
                  (label ,label)
                  (device ,(device->sexp device))
                  (device-mount-point ,mount-point)
                  (chain-loader ,chain-loader)))
    (_ (report-menu-entry-error entry))))

(define (sexp->menu-entry sexp)
  "Turn SEXP, an sexp as returned by 'menu-entry->sexp', into a <menu-entry>
record."
  (define (sexp->device device-sexp)
    (match device-sexp
      (('uuid type uuid-string)
       (uuid uuid-string type))
      (('label label)
       (file-system-label label))
      (_ device-sexp)))
  (match sexp
    (('menu-entry ('version 0)
                  ('label label) ('device device)
                  ('device-mount-point mount-point)
                  ('linux linux) ('linux-arguments linux-arguments)
                  ('initrd initrd) _ ...)
     (menu-entry
      (label label)
      (device (sexp->device device))
      (device-mount-point mount-point)
      (linux linux)
      (linux-arguments linux-arguments)
      (initrd initrd)))
    (('menu-entry ('version 0)
                  ('label label) ('device device)
                  ('device-mount-point mount-point)
                  ('multiboot-kernel multiboot-kernel)
                  ('multiboot-arguments multiboot-arguments)
                  ('multiboot-modules multiboot-modules) _ ...)
     (menu-entry
      (label label)
      (device (sexp->device device))
      (device-mount-point mount-point)
      (multiboot-kernel multiboot-kernel)
      (multiboot-arguments multiboot-arguments)
      (multiboot-modules multiboot-modules)))
    (('menu-entry ('version 0)
                  ('label label) ('device device)
                  ('device-mount-point mount-point)
                  ('chain-loader chain-loader) _ ...)
     (menu-entry
      (label label)
      (device (sexp->device device))
      (device-mount-point mount-point)
      (chain-loader chain-loader)))))

\f
;;;
;;; Bootloader record.
;;;

;; The <bootloader> record contains fields expressing how the bootloader
;; should be installed. Every bootloader in gnu/bootloader/ directory
;; has to be described by this record.

(define-record-type* <bootloader>
  bootloader make-bootloader
  bootloader?
  (name                            bootloader-name)
  (package                         bootloader-package)
  (installer                       bootloader-installer)
  (disk-image-installer            bootloader-disk-image-installer
                                   (default #f))
  (configuration-file              bootloader-configuration-file)
  (configuration-file-generator    bootloader-configuration-file-generator))

\f
;;;
;;; Bootloader target record.
;;;

;; <bootloader-target> represents different kinds of targets in a normalized form.

(define-record-type* <bootloader-target>
  bootloader-target make-bootloader-target bootloader-target?
  (type bootloader-target-type)                            ; symbol
  (expected? bootloader-target-expected? (default #f))     ; bool

  (path bootloader-target-path (default #f))               ; string|#f
  (offset bootloader-target-offset (thunked)               ; symbol|#f
          (default (and (bootloader-target-path this-record)
                        (not (eq? (bootloader-target-type this-record) 'root))
                        'root)))
  (device bootloader-target-device (default #f))           ; string|#f
  (file-system bootloader-target-file-system (default #f)) ; string|#f
  (label bootloader-target-label (default #f))             ; string|#f
  (uuid bootloader-target-uuid (default #f)))              ; uuid|#f

(define-condition-type &target-error &error target-error?
  (type target-error-type)
  (targets target-error-targets))

(define (pathcat p1 p2)
  (string-append (string-trim-right p1 #\/) "/" (string-trim p2 #\/)))

(define* (get-target-of-type type targets #:optional (require? #f))
  "Finds a target in TARGETS of type TYPE, optionally providing an error when
not found if REQUIRE? is provided."
  (let* ((pred (lambda (target) (eq? type (bootloader-target-type target))))
         (candidates (filter pred targets))
         (ret (if (pair? candidates) (car candidates) #f)))
    (if (and require? (not ret))
      (raise (condition
               (&message (message (G_ "required, but not provided")))
               (&target-error (type type) (targets targets))))
      ret)))

(define (parent-of target targets)
  (and=> (bootloader-target-offset target)
         (cut get-target-of-type <> targets #t)))

(define (unfold-pathcat target targets)
  (let ((quit (lambda (t) (not (and=> t bootloader-target-path)))))
    (reduce pathcat #f
      (unfold quit bootloader-target-path (cut parent-of <> targets) target))))

(define (target-base? t)
  (or (not t) (match-record t <bootloader-target>
                (expected? offset device label uuid)
                (or device label uuid (not offset) expected?))))

(define (type-major? target) (memq target '(root esp disk)))

(define (ensure types targets end)
  (let* ((used-in (cute unfold end identity (cut parent-of <> targets) <>))
         (cons-in (lambda (t) (cons t (used-in t))))
         (ensure (map (cut get-target-of-type <> targets #t) types)))
    (filter ->bool (apply append (map cons-in ensure)))))

(define* (ensure-target-types types targets #:optional (base? #f))
  "Ensures all TYPES are provided in TARGETS.  Returns #t iff every ensured
target and its requirements are fully provided.  Errors out when a required TYPE
isn't provided.  When BASE?, only ensure path requirements up to a device."
  (not (any bootloader-target-expected?
         (ensure types targets (if base? target-base? not)))))

(define (ensure-majors types targets)
  "Errors out when a required TYPE isn't provided, or when use of multiple major
targets is detected."
  (let* ((all (map bootloader-target-type (ensure types targets target-base?)))
         (majors (delete-duplicates (filter type-major? all) eq?)))
    (if (< (length majors) 2) #t
      (raise (condition (&message (message (G_ "multiple major targets used")))
                        (&target-error (type majors) (targets targets)))))))



(define (gbegin . gex)
  "Sequence provided g-expressions."
  (case (length gex) ((0) #f) ((1) (car gex)) (else #~(begin #$@gex))))

;; syntax matching on free literals breaks easily, so bind them
(define-syntax-rule (define-literal id) (define-syntax id (syntax-rules ())))
(define-literal :path)
(define-literal :devpath)
(define-literal :device)
(define-literal :fs)
(define-literal :label)
(define-literal :uuid)

(define-syntax with-targets
  (cut syntax-case <> ()
    ((_ targets-expr block ...)
     (let* ((genvars (compose generate-temporaries iota))
            (targets (car (genvars 1)))

            (path? (cut syntax-case <> (:path) ((_ :path) #t) (_ #f)))
            (qualified? (cut syntax-case <> (=>)
                          ((_ => spec ...) (any path? #'(spec ...)))
                          (_ #f)))

            (resolve
              (lambda (in target base)
                (with-syntax ((target target) (base base) (targets targets))
                  (syntax-case in
                    (:path :devpath :device :fs :label :uuid)
                    ((name _) (not (identifier? #'name))
                     #`(_ (syntax-error "binds must be to identifiers" #,in)))
                    ((name :device) #'(name (bootloader-target-device base)))
                    ((name :label) #'(name (bootloader-target-label base)))
                    ((name :uuid) #'(name (bootloader-target-uuid base)))
                    ((name :fs) #'(name (bootloader-target-file-system base)))
                    ((name :path) #'(name (unfold-pathcat target targets)))
                    ((name :devpath)
                     #'(name (pathcat "/" (bootloader-target-path target))))
                    (_ #`(_ (syntax-error "invalid binding spec" #,in)))))))
            (binds
              (lambda (spec)
                (syntax-case spec (=>)
                  ((type => binds ...)
                   (with-syntax (((target base) (genvars 2)) (targets targets))
                     (append
                       #`((get (lambda (t) (get-target-of-type t targets #t)))
                          (target (get type))
                          (base (if (target-base? target) target
                                  (get (bootloader-target-offset target)))))
                       (map (cut resolve <> #'target #'base) #'(binds ...)))))
                  (_ #f))))

            (blocks
              (cut syntax-case <> ()
                ((spec ... expr)
                 (let* ((specs #'(spec ...))
                        (lets (apply append (filter-map binds specs)))
                        (type (cut syntax-case <> (=>)
                                ((t => _ ...) #'t) (t #'t))))
                   (receive (full part) (partition qualified? specs)
                     #`(and (ensure-majors (list #,@(map type specs)) #,targets)
                            (ensure-target-types (list #,@(map type part))
                                                 #,targets #t)
                            (ensure-target-types (list #,@(map type full))
                                                 #,targets #f)
                            (let* #,lets expr)))))
                (bad #'(syntax-error "malformed block" bad)))))
       "Using the list TARGETS, evaluate and sequence each BLOCK to produce a
gexp. BLOCK is a set of SPECs followed by an EXPR (evaluating to a gexp). Each
SPEC denotes a type of target to guard EXPR on their existance and
full-qualification. This procedure is linear in regards to BLOCKs.

SPEC may be of the following forms:
@itemize
@item 'TYPE Requires TYPE to be fully present or promised. Errors otherwise.
@item ('TYPE => (VAR COMPONENT) ...): As type, but also binds variables. TYPE's
      COMPONENT is bound to the variable VAR as described below.
@end itemize

Available COMPONENTs are:
@itemize
@item :path (fully-qualified)
@item :devpath (relative from device)
@item :device (auto-detected from uuid and label if not user-provided)
@item :fs
@item :label
@item :uuid
@end itemize

Note that installers may be called multiple times with different targets being
fully-qualified.  To ensure that targets aren't installed multiple times, make sure
that each BLOCK ensures at least one major target, either directly or indirectly.
Corrolarily, at most one major target should be ensured per BLOCK, under the same
conditions. Major targets originate from disk image handling, and are currently:
@itemize
@item disk
@item root
@item esp
@end itemize"
       #`(let ((#,targets targets-expr))
           (apply gbegin (filter ->bool
                           (list #,@(map blocks #'(block ...))))))))
    (bad #'(syntax-error "must provide targets" bad))))

\f
;;;
;;; Bootloader configuration record.
;;;

;; The <bootloader-configuration> record contains bootloader independant
;; configuration used to fill bootloader configuration file.

(define-with-syntax-properties (warn-target-field-deprecation
                                (value properties))
  (when value
    (warning (source-properties->location properties)
             (G_ "the 'target' field is deprecated, please use 'targets' \
instead~%")))
  value)

(define-record-type* <bootloader-configuration>
  bootloader-configuration make-bootloader-configuration
  bootloader-configuration?
  (bootloader
   bootloader-configuration-bootloader) ;<bootloader>
  (targets               %bootloader-configuration-targets
                         (default #f))     ;list of strings
  (target                %bootloader-configuration-target ;deprecated
                         (default #f)
                         (sanitize warn-target-field-deprecation))
  (menu-entries          bootloader-configuration-menu-entries
                         (default '()))   ;list of <menu-entry>
  (default-entry         bootloader-configuration-default-entry
                         (default 0))     ;integer
  (timeout               bootloader-configuration-timeout
                         (default 5))     ;seconds as integer
  (keyboard-layout       bootloader-configuration-keyboard-layout
                         (default #f))    ;<keyboard-layout> | #f
  (theme                 bootloader-configuration-theme
                         (default #f))    ;bootloader-specific theme
  (terminal-outputs      bootloader-configuration-terminal-outputs
                         (default '(gfxterm)))   ;list of symbols
  (terminal-inputs       bootloader-configuration-terminal-inputs
                         (default '()))   ;list of symbols
  (serial-unit           bootloader-configuration-serial-unit
                         (default #f))    ;integer | #f
  (serial-speed          bootloader-configuration-serial-speed
                         (default #f))    ;integer | #f
  (device-tree-support?  bootloader-configuration-device-tree-support?
                         (default #t))    ;boolean
  (extra-initrd          bootloader-configuration-extra-initrd
                         (default #f)))   ;string | #f

(define-deprecated (bootloader-configuration-target config)
  bootloader-configuration-targets
  (%bootloader-configuration-target config))

(define (bootloader-configuration-targets config)
  (or (%bootloader-configuration-targets config)
      ;; TODO: Remove after the deprecated 'target' field is removed.
      (list (%bootloader-configuration-target config))
      ;; XXX: At least the GRUB installer (see (gnu bootloader grub)) has this
      ;; peculiar behavior of installing fonts and GRUB modules when DEVICE is #f,
      ;; hence the default value of '(#f) rather than '().
      (list #f)))

\f
;;;
;;; Bootloaders.
;;;

(define (bootloader-modules)
  "Return the list of bootloader modules."
  ;; don't provide #:warn to prevent mutual imports
  (all-modules (map (lambda (entry)
                      `(,entry . "gnu/bootloader"))
                    %load-path)))

(define %bootloaders
  ;; The list of publically-known bootloaders.
  (delay (fold-module-public-variables (lambda (obj result)
                                         (if (bootloader? obj)
                                             (cons obj result)
                                             result))
                                       '()
                                       (bootloader-modules))))

(define (lookup-bootloader-by-name name)
  "Return the bootloader called NAME."
  (or (find (lambda (bootloader)
              (eq? name (bootloader-name bootloader)))
            (force %bootloaders))
      (leave (G_ "~a: no such bootloader~%") name)))

(define (efi-bootloader-profile packages files hooks)
  "Creates a profile from the lists of PACKAGES and FILES from the store.
This profile is meant to be used by the bootloader-installer.

FILES is a list of file or directory names from the store, which will be
symlinked into the profile.  If a directory name ends with '/', then the
directory content instead of the directory itself will be symlinked into the
profile.

FILES may contain file like objects produced by procedures like plain-file,
local-file, etc., or package contents produced with file-append.

HOOKS lists additional hook functions to modify the profile."
  (define* (efi-bootloader-profile-hook manifest #:optional system)
    (define build
        (with-imported-modules '((guix build utils))
          #~(begin
            (use-modules ((guix build utils)
                          #:select (mkdir-p strip-store-file-name))
                         ((ice-9 ftw)
                          #:select (scandir))
                         ((srfi srfi-1)
                          #:select (append-map every remove))
                         ((srfi srfi-26)
                          #:select (cut)))
            (define (symlink-to file directory transform)
              "Creates a symlink to FILE named (TRANSFORM FILE) in DIRECTORY."
              (symlink file (string-append directory "/" (transform file))))
            (define (directory-content directory)
              "Creates a list of absolute path names inside DIRECTORY."
              (map (lambda (name)
                     (string-append directory name))
                   (or (scandir directory (lambda (name)
                                            (not (member name '("." "..")))))
                       '())))
            (define name-ends-with-/? (cut string-suffix? "/" <>))
            (define (name-is-store-entry? name)
              "Return #t if NAME is a direct store entry and nothing inside."
              (not (string-index (strip-store-file-name name) #\/)))
            (let* ((files '#$files)
                   (directories (filter name-ends-with-/? files))
                   (names-from-directories
                    (append-map (lambda (directory)
                                  (directory-content directory))
                                directories))
                   (names (append names-from-directories
                                  (remove name-ends-with-/? files))))
              (mkdir-p #$output)
              (if (every file-exists? names)
                  (begin
                    (for-each (lambda (name)
                               (symlink-to name #$output
                                            (if (name-is-store-entry? name)
                                                strip-store-file-name
                                                basename)))
                              names)
                    #t)
                  #f)))))

    (gexp->derivation "efi-bootloader-profile"
                      build
                      #:system system
                      #:local-build? #t
                      #:substitutable? #f
                      #:properties
                      `((type . profile-hook)
                        (hook . efi-bootloader-profile-hook))))

  (profile (content (packages->manifest packages))
           (name "efi-bootloader-profile")
           (hooks (cons efi-bootloader-profile-hook hooks))
           (locales? #f)
           (allow-collisions? #f)
           (relative-symlinks? #f)))

(define* (efi-bootloader-chain final-bootloader
                               #:key
                               (packages '())
                               (files '())
                               (hooks '())
                               installer
                               disk-image-installer)
  "Define a chain of bootloaders with the FINAL-BOOTLOADER, optional PACKAGES,
and optional directories and files from the store given in the list of FILES.

The package of the FINAL-BOOTLOADER and all PACKAGES and FILES will be placed
in an efi-bootloader-profile, which will be passed to the INSTALLER.

FILES may contain file-like objects produced by procedures like plain-file,
local-file, etc., or package contents produced with file-append.

If a directory name in FILES ends with '/', then the directory content instead
of the directory itself will be symlinked into the efi-bootloader-profile.

The procedures in the HOOKS list can be used to further modify the bootloader
profile.  It is possible to pass a single function instead of a list.

If the INSTALLER argument is used, then this gexp procedure will be called to
install the efi-bootloader-profile.  Otherwise the installer of the
FINAL-BOOTLOADER will be called.

If the DISK-IMAGE-INSTALLER is used, then this gexp procedure will be called
to install the efi-bootloader-profile into a disk image.  Otherwise the
disk-image-installer of the FINAL-BOOTLOADER will be called."
  (bootloader
    (inherit final-bootloader)
    (name "efi-bootloader-chain")
    (package
     (efi-bootloader-profile (cons (bootloader-package final-bootloader)
                                   packages)
                             files
                             (if (list? hooks)
                                 hooks
                                 (list hooks))))
    (installer
     (or installer
         (bootloader-installer final-bootloader)))
    (disk-image-installer
     (or disk-image-installer
         (bootloader-disk-image-installer final-bootloader)))))