;;; marginalia.el --- Enrich existing commands with completion annotations -*- lexical-binding: t -*-

;; Copyright (C) 2021-2023 Free Software Foundation, Inc.

;; Author: Omar Antolín Camarena <omar@matem.unam.mx>, Daniel Mendler <mail@daniel-mendler.de>
;; Maintainer: Omar Antolín Camarena <omar@matem.unam.mx>, Daniel Mendler <mail@daniel-mendler.de>
;; Created: 2020
;; Version: 1.1
;; Package-Version: 20230217.2050
;; Package-Commit: ccf573e2145d9deb9d734432351eefc87fc1bc16
;; Package-Requires: ((emacs "27.1") (compat "29.1.3.4"))
;; Homepage: https://github.com/minad/marginalia

;; This file is part of GNU Emacs.

;; This program 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.

;; This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.

;;; Commentary:

;; Enrich existing commands with completion annotations

;;; Code:

(require 'compat)
(eval-when-compile
  (require 'subr-x)
  (require 'cl-lib))

;;;; Customization

(defgroup marginalia nil
  "Enrich existing commands with completion annotations."
  :link '(info-link :tag "Info Manual" "(marginalia)")
  :link '(url-link :tag "Homepage" "https://github.com/minad/marginalia")
  :link '(emacs-library-link :tag "Library Source" "marginalia.el")
  :group 'help
  :group 'docs
  :group 'minibuffer
  :prefix "marginalia-")

(defcustom marginalia-field-width 80
  "Maximum truncation width of annotation fields.

This value is adjusted depending on the `window-width'."
  :type 'integer)

(defcustom marginalia-separator "  "
  "Annotation field separator."
  :type 'string)

(defcustom marginalia-align 'left
  "Alignment of the annotations."
  :type '(choice (const :tag "Left"   left)
                 (const :tag "Center" center)
                 (const :tag "Right"  right)))

(defcustom marginalia-align-offset 0
  "Additional offset added to the alignment."
  :type 'integer)

(defcustom marginalia-max-relative-age (* 60 60 24 14)
  "Maximum relative age in seconds displayed by the file annotator.

Set to `most-positive-fixnum' to always use a relative age, or 0 to never show
a relative age."
  :type 'integer)

(defcustom marginalia-annotator-registry
  (mapcar
   (lambda (x) (append x '(builtin none)))
   '((command marginalia-annotate-command marginalia-annotate-binding)
     (embark-keybinding marginalia-annotate-embark-keybinding)
     (customize-group marginalia-annotate-customize-group)
     (variable marginalia-annotate-variable)
     (function marginalia-annotate-function)
     (face marginalia-annotate-face)
     (color marginalia-annotate-color)
     (unicode-name marginalia-annotate-char)
     (minor-mode marginalia-annotate-minor-mode)
     (symbol marginalia-annotate-symbol)
     (environment-variable marginalia-annotate-environment-variable)
     (input-method marginalia-annotate-input-method)
     (coding-system marginalia-annotate-coding-system)
     (charset marginalia-annotate-charset)
     (package marginalia-annotate-package)
     (imenu marginalia-annotate-imenu)
     (bookmark marginalia-annotate-bookmark)
     (file marginalia-annotate-file)
     (project-file marginalia-annotate-project-file)
     (buffer marginalia-annotate-buffer)
     (library marginalia-annotate-library)
     (tab marginalia-annotate-tab)
     (multi-category marginalia-annotate-multi-category)))
  "Annotator function registry.
Associates completion categories with annotation functions.
Each annotation function must return a string,
which is appended to the completion candidate."
  :type '(alist :key-type symbol :value-type (repeat symbol)))

(defcustom marginalia-classifiers
  '(marginalia-classify-by-command-name
    marginalia-classify-original-category
    marginalia-classify-by-prompt
    marginalia-classify-symbol)
  "List of functions to determine current completion category.
Each function should take no arguments and return a symbol
indicating the category, or nil to indicate it could not
determine it."
  :type 'hook)

(defcustom marginalia-prompt-categories
  '(("\\<customize group\\>" . customize-group)
    ("\\<M-x\\>" . command)
    ("\\<package\\>" . package)
    ("\\<bookmark\\>" . bookmark)
    ("\\<color\\>" . color)
    ("\\<face\\>" . face)
    ("\\<environment variable\\>" . environment-variable)
    ("\\<function\\|hook to remove\\>" . function)
    ("\\<variable\\>" . variable)
    ("\\<input method\\>" . input-method)
    ("\\<charset\\>" . charset)
    ("\\<coding system\\>" . coding-system)
    ("\\<minor mode\\>" . minor-mode)
    ("\\<kill-ring\\>" . kill-ring)
    ("\\<tab by name\\>" . tab)
    ("\\<[Ll]ibrary\\>" . library))
  "Associates regexps to match against minibuffer prompts with categories."
  :type '(alist :key-type regexp :value-type symbol))

(defcustom marginalia-censor-variables
  '("pass\\|auth-source-netrc-cache\\|auth-source-.*-nonce")
  "The value of variables matching any of these regular expressions is not shown.
This configuration variable is useful to hide variables which may
hold sensitive data, e.g., passwords."
  :type '(repeat (choice symbol regexp)))

(defcustom marginalia-command-categories
  '((imenu . imenu)
    (recentf-open . file))
  "Associate commands with a completion category."
  :type '(alist :key-type symbol :value-type symbol))

(defgroup marginalia-faces nil
  "Faces used by `marginalia-mode'."
  :group 'marginalia
  :group 'faces)

(defface marginalia-key
  '((t :inherit font-lock-keyword-face))
  "Face used to highlight keys.")

(defface marginalia-type
  '((t :inherit marginalia-key))
  "Face used to highlight types.")

(defface marginalia-char
  '((t :inherit marginalia-key))
  "Face used to highlight character annotations.")

(defface marginalia-lighter
  '((t :inherit marginalia-size))
  "Face used to highlight minor mode lighters.")

(defface marginalia-on
  '((t :inherit success))
  "Face used to signal enabled modes.")

(defface marginalia-off
  '((t :inherit error))
  "Face used to signal disabled modes.")

(defface marginalia-documentation
  '((t :inherit completions-annotations))
  "Face used to highlight documentation strings.")

(defface marginalia-value
  '((t :inherit marginalia-key))
  "Face used to highlight general variable values.")

(defface marginalia-null
  '((t :inherit font-lock-comment-face))
  "Face used to highlight null or unbound variable values.")

(defface marginalia-true
  '((t :inherit font-lock-builtin-face))
  "Face used to highlight true variable values.")

(defface marginalia-function
  '((t :inherit font-lock-function-name-face))
  "Face used to highlight function symbols.")

(defface marginalia-symbol
  '((t :inherit font-lock-type-face))
  "Face used to highlight general symbols.")

(defface marginalia-list
  '((t :inherit font-lock-constant-face))
  "Face used to highlight list expressions.")

(defface marginalia-mode
  '((t :inherit marginalia-key))
  "Face used to highlight buffer major modes.")

(defface marginalia-date
  '((t :inherit marginalia-key))
  "Face used to highlight dates.")

(defface marginalia-version
  '((t :inherit marginalia-number))
  "Face used to highlight package versions.")

(defface marginalia-archive
  '((t :inherit warning))
  "Face used to highlight package archives.")

(defface marginalia-installed
  '((t :inherit success))
  "Face used to highlight the status of packages.")

(defface marginalia-size
  '((t :inherit marginalia-number))
  "Face used to highlight sizes.")

(defface marginalia-number
  '((t :inherit font-lock-constant-face))
  "Face used to highlight numeric values.")

(defface marginalia-string
  '((t :inherit font-lock-string-face))
  "Face used to highlight string values.")

(defface marginalia-modified
  '((t :inherit font-lock-negation-char-face))
  "Face used to highlight buffer modification indicators.")

(defface marginalia-file-name
  '((t :inherit marginalia-documentation))
  "Face used to highlight file names.")

(defface marginalia-file-owner
  '((t :inherit font-lock-preprocessor-face))
  "Face used to highlight file owner and group names.")

(defface marginalia-file-priv-no
  '((t :inherit shadow))
  "Face used to highlight the no file privilege attribute.")

(defface marginalia-file-priv-dir
  '((t :inherit font-lock-keyword-face))
  "Face used to highlight the dir file privilege attribute.")

(defface marginalia-file-priv-link
  '((t :inherit font-lock-keyword-face))
  "Face used to highlight the link file privilege attribute.")

(defface marginalia-file-priv-read
  '((t :inherit font-lock-type-face))
  "Face used to highlight the read file privilege attribute.")

(defface marginalia-file-priv-write
  '((t :inherit font-lock-builtin-face))
  "Face used to highlight the write file privilege attribute.")

(defface marginalia-file-priv-exec
  '((t :inherit font-lock-function-name-face))
  "Face used to highlight the exec file privilege attribute.")

(defface marginalia-file-priv-other
  '((t :inherit font-lock-constant-face))
  "Face used to highlight some other file privilege attribute.")

(defface marginalia-file-priv-rare
  '((t :inherit font-lock-variable-name-face))
  "Face used to highlight a rare file privilege attribute.")

;;;; Pre-declarations for external packages

(declare-function project-current "project")

(declare-function bookmark-get-handler "bookmark")
(declare-function bookmark-get-filename "bookmark")
(declare-function bookmark-get-front-context-string "bookmark")

(defvar package--builtins)
(defvar package-archive-contents)
(declare-function package--from-builtin "package")
(declare-function package-desc-archive "package")
(declare-function package-desc-status "package")
(declare-function package-desc-summary "package")
(declare-function package-desc-version "package")
(declare-function package-version-join "package")

(declare-function color-rgb-to-hex "color")
(declare-function color-rgb-to-hsl "color")
(declare-function color-hsl-to-rgb "color")

;;;; Marginalia mode

(defvar marginalia--pangram "Cwm fjord bank glyphs vext quiz.")

(defvar marginalia--bookmark-type-transforms
  (let ((words (regexp-opt '("handle" "handler" "jump" "bookmark"))))
    `((,(format "-+%s-+" words) . "-")
      (,(format "\\`%s-+" words) . "")
      (,(format "-%s\\'" words) . "")
      ("\\`default\\'" . "File")
      (".*" . ,#'capitalize)))
  "List of bookmark type transformers.
Relying on this mechanism is discouraged in favor of the
`bookmark-handler-type' property.")

(defvar marginalia--cand-width-step 10
  "Round candidate width.")

(defvar-local marginalia--cand-width-max 20
  "Maximum width of candidates.")

(defvar marginalia--fontified-file-modes nil
  "List of fontified file modes.")

(defvar-local marginalia--cache nil
  "The cache, pair of list and hashtable.")

(defvar marginalia--cache-size 100
  "Size of the cache, set to 0 to disable the cache.
Disabling the cache is useful on non-incremental UIs like default completion or
for performance profiling of the annotators.")

(defvar-local marginalia--command nil
  "Last command symbol saved in order to allow annotations.")

(defvar-local marginalia--base-position 0
  "Last completion base position saved to get full file paths.")

(defvar marginalia--metadata nil
  "Completion metadata from the current completion.")

(defvar marginalia--ellipsis nil)
(defun marginalia--ellipsis ()
  "Return ellipsis."
  (with-memoization marginalia--ellipsis
    ;; TODO Emacs 28 offers the function `truncate-string-ellipsis'.
    ;; It must be backported in Compat.
    (cond
     ((bound-and-true-p truncate-string-ellipsis))
     ((char-displayable-p ?…) "")
     ("..."))))

(defun marginalia--truncate (str width)
  "Truncate string STR to WIDTH."
  (when (floatp width) (setq width (round (* width marginalia-field-width))))
  (when-let (pos (string-search "\n" str))
    (setq str (substring str 0 pos)))
  (let* ((face (and (not (equal str ""))
                    (get-text-property (1- (length str)) 'face str)))
         (ell (if face
                  (propertize (marginalia--ellipsis) 'face face)
                (marginalia--ellipsis)))
         (trunc
          (if (< width 0)
              (nreverse (truncate-string-to-width (reverse str) (- width) 0 ?\s ell))
            (truncate-string-to-width str width 0 ?\s ell))))
    (unless (string-prefix-p str trunc)
      (put-text-property 0 (length trunc) 'help-echo str trunc))
    trunc))

(cl-defmacro marginalia--field (field &key truncate face width format)
  "Format FIELD as a string according to some options.
TRUNCATE is the truncation width.
WIDTH is the field width.
FORMAT is a format string.
FACE is the name of the face, with which the field should be propertized."
  (setq field (if format `(format ,format ,field) `(or ,field "")))
  (when width (setq field `(format ,(format "%%%ds" (- width)) ,field)))
  (when truncate (setq field `(marginalia--truncate ,field ,truncate)))
  (when face (setq field `(propertize ,field 'face ,face)))
  field)

(defmacro marginalia--fields (&rest fields)
  "Format annotation FIELDS as a string with separators in between."
  (let ((left t))
    (cons 'concat
          (mapcan
           (lambda (field)
             (if (not (eq (car field) :left))
                 `(,@(when left (setq left nil) `(#(" " 0 1 (marginalia--align t))))
                   marginalia-separator (marginalia--field ,@field))
               (unless left (error "Left fields must come first"))
               `((marginalia--field ,@(cdr field)))))
           fields))))

(defun marginalia--documentation (str)
  "Format documentation string STR."
  (when str
    (marginalia--fields
     (str :truncate 1.0 :face 'marginalia-documentation))))

(defun marginalia-annotate-binding (cand)
  "Annotate command CAND with keybinding."
  (when-let ((sym (intern-soft cand))
             (key (and (commandp sym) (where-is-internal sym nil 'first-only))))
    (format #(" (%s)" 1 5 (face marginalia-key)) (key-description key))))

(defun marginalia--annotator (cat)
  "Return annotation function for category CAT."
  (pcase (car (alist-get cat marginalia-annotator-registry))
    ('none #'ignore)
    ('builtin nil)
    (fun fun)))

(defun marginalia-annotate-multi-category (cand)
  "Annotate multi-category CAND with the buffer class."
  (if-let ((multi (get-text-property 0 'multi-category cand))
           (annotate (marginalia--annotator (car multi))))
      ;; Use the Marginalia annotator corresponding to the multi category.
      (funcall annotate (cdr multi))
    ;; Apply the original annotation function on the original candidate, if
    ;; there is one.  NOTE: Use `alist-get' instead of `completion-metadata-get'
    ;; to bypass our `marginalia--completion-metadata-get' advice!
    (when-let (annotate (alist-get 'annotation-function marginalia--metadata))
      (funcall annotate cand))))

(defconst marginalia--advice-regexp
  (rx bos
      (1+ (seq (? "This function has ")
               (or ":before" ":after" ":around" ":override"
                   ":before-while" ":before-until" ":after-while"
                   ":after-until" ":filter-args" ":filter-return")
               " advice: " (0+ nonl) "\n"))
      "\n")
  "Regexp to match lines about advice in function documentation strings.")

;; Taken from advice--make-docstring, is this robust?
(defun marginalia--advised (fun)
  "Return t if function FUN is advised."
  (let ((flist (indirect-function fun)))
    (advice--p (if (eq 'macro (car-safe flist)) (cdr flist) flist))))

(defun marginalia--symbol-class (s)
  "Return symbol class characters for symbol S.

This function is an extension of `help--symbol-class'.  It returns
more fine-grained and more detailled symbol information.

Function:
f function
c command
C interactive-only command
m macro
M special-form
g cl-generic
p pure
s side-effect-free
@ autoloaded
! advised
- obsolete
& alias

Variable:
u custom (U modified compared to global value)
v variable
l local (L modified compared to default value)
- obsolete
& alias

Other:
a face
t cl-type"
  (let ((class
         (append
          (when (fboundp s)
            (list
             (cond
              ((get s 'pure) '("p" . "pure"))
              ((get s 'side-effect-free) '("s" . "side-effect-free")))
             (cond
              ((commandp s)
               (if (get s 'interactive-only)
                   '("C" . "interactive-only command")
                 '("c" . "command")))
              ((cl-generic-p s) '("g" . "cl-generic"))
              ((macrop (symbol-function s)) '("m" . "macro"))
              ((special-form-p (symbol-function s)) '("M" . "special-form"))
              (t '("f" . "function")))
             (and (autoloadp (symbol-function s)) '("@" . "autoload"))
             (and (marginalia--advised s) '("!" . "advised"))
             (and (symbolp (symbol-function s))
                  (cons "&" (format "alias for `%s'" (symbol-function s))))
             (and (get s 'byte-obsolete-info) '("-" . "obsolete"))))
          (when (boundp s)
            (list
             (when (local-variable-if-set-p s)
               (if (ignore-errors
                     (not (equal (symbol-value s)
                                 (default-value s))))
                   '("L" . "local, modified from global")
                 '("l" . "local, unmodified")))
             (if (custom-variable-p s)
                 (if (ignore-errors
                       (not (equal (symbol-value s)
                                   (eval (car (get s 'standard-value))))))
                     '("U" . "custom, modified from standard")
                   '("u" . "custom, unmodified"))
               '("v" . "variable"))
             (and (not (eq (ignore-errors (indirect-variable s)) s))
                  (cons "&" (format "alias for `%s'" (ignore-errors (indirect-variable s)))))
             (and (get s 'byte-obsolete-variable) '("-" . "obsolete"))))
          (list
           (and (facep s) '("a" . "face"))
           (and (get s 'cl--class) '("t" . "cl-type")))))) ;; cl-find-class, cl--find-class
    (setq class (delq nil class))
    (propertize
     (format " %-6s" (mapconcat #'car class ""))
     'help-echo
     (mapconcat (pcase-lambda (`(,x . ,y)) (concat x " " y)) class "\n"))))

(defun marginalia--function-doc (sym)
  "Documentation string of function SYM."
  (when-let (str (ignore-errors (documentation sym)))
    (save-match-data
      (if (string-match marginalia--advice-regexp str)
          (substring str (match-end 0))
        str))))

;; Derived from elisp-get-fnsym-args-string
(defun marginalia--function-args (sym)
  "Return function arguments for SYM."
  (let ((tmp))
    (elisp-function-argstring
     (cond
      ((listp (setq tmp (gethash (indirect-function sym)
                                 advertised-signature-table t)))
       tmp)
      ((setq tmp (help-split-fundoc
                  (ignore-errors (documentation sym t))
                  sym))
       (substitute-command-keys (car tmp)))
      ((setq tmp (help-function-arglist sym))
       (and
        (if (and (stringp tmp)
                 (string-search "Arg list not available" tmp))
            ;; A shorter text fits better into the
            ;; limited Marginalia space.
            "[autoload]"
          tmp)))))))

(defun marginalia-annotate-symbol (cand)
  "Annotate symbol CAND with its documentation string."
  (when-let (sym (intern-soft cand))
    (marginalia--fields
     (:left (marginalia-annotate-binding cand))
     ((marginalia--symbol-class sym) :face 'marginalia-type)
     ((cond
       ((fboundp sym) (marginalia--function-doc sym))
       ((facep sym) (documentation-property sym 'face-documentation))
       (t (documentation-property sym 'variable-documentation)))
      :truncate 1.0 :face 'marginalia-documentation))))

(defun marginalia-annotate-command (cand)
  "Annotate command CAND with its documentation string.
Similar to `marginalia-annotate-symbol', but does not show symbol class."
  (when-let (sym (intern-soft cand))
    (concat
     (marginalia-annotate-binding cand)
     (marginalia--documentation (marginalia--function-doc sym)))))

(defun marginalia-annotate-embark-keybinding (cand)
  "Annotate Embark keybinding CAND with its documentation string.
Similar to `marginalia-annotate-command', but does not show the
keybinding since CAND includes it."
  (when-let (cmd (get-text-property 0 'embark-command cand))
    (marginalia--documentation (marginalia--function-doc cmd))))

(defun marginalia-annotate-imenu (cand)
  "Annotate imenu CAND with its documentation string."
  (when (derived-mode-p 'emacs-lisp-mode)
    ;; Strip until the last whitespace in order to support flat imenu
    (marginalia-annotate-symbol (replace-regexp-in-string "^.* " "" cand))))

(defun marginalia-annotate-function (cand)
  "Annotate function CAND with its documentation string."
  (when-let (sym (intern-soft cand))
    (when (fboundp sym)
      (marginalia--fields
       (:left (marginalia-annotate-binding cand))
       ((marginalia--symbol-class sym) :face 'marginalia-type)
       ((marginalia--function-args sym) :face 'marginalia-value
        :truncate 0.5)
       ((marginalia--function-doc sym) :truncate 1.0
        :face 'marginalia-documentation)))))

(defun marginalia--variable-value (sym)
  "Return the variable value of SYM as string."
  (cond
   ((not (boundp sym))
    (propertize "#<unbound>" 'face 'marginalia-null))
   ((and marginalia-censor-variables
         (let ((name (symbol-name sym)))
           (cl-loop for r in marginalia-censor-variables
                    thereis (if (symbolp r)
                                (eq r sym)
                              (string-match-p r name)))))
    (propertize "*****" 'face 'marginalia-null))
   (t
    (let ((val (symbol-value sym)))
      (pcase val
        ('nil (propertize "nil" 'face 'marginalia-null))
        ('t (propertize "t" 'face 'marginalia-true))
        ((pred keymapp) (propertize "#<keymap>" 'face 'marginalia-value))
        ((pred bool-vector-p) (propertize "#<bool-vector>" 'face 'marginalia-value))
        ((pred hash-table-p) (propertize "#<hash-table>" 'face 'marginalia-value))
        ((pred syntax-table-p) (propertize "#<syntax-table>" 'face 'marginalia-value))
        ;; Emacs bug#53988: abbrev-table-p throws an error
        ((and (pred vectorp) (guard (ignore-errors (abbrev-table-p val))))
         (propertize "#<abbrev-table>" 'face 'marginalia-value))
        ((pred char-table-p) (propertize "#<char-table>" 'face 'marginalia-value))
        ;; Emacs 29 comes with callable objects or object closures (OClosures)
        ((guard (and (fboundp 'oclosure-type) (oclosure-type val)))
         (format (propertize "#<oclosure %s>" 'face 'marginalia-function)
                 (and (fboundp 'oclosure-type) (oclosure-type val))))
        ((pred byte-code-function-p) (propertize "#<byte-code-function>" 'face 'marginalia-function))
        ((and (pred functionp) (pred symbolp))
         ;; NOTE: We are not consistent here, values are generally printed unquoted. But we
         ;; make an exception for function symbols to visually distinguish them from symbols.
         ;; I am not entirely happy with this, but we should not add quotation to every type.
         (format (propertize "#'%s" 'face 'marginalia-function) val))
        ((pred recordp) (format (propertize "#<record %s>" 'face 'marginalia-value) (type-of val)))
        ((pred symbolp) (propertize (symbol-name val) 'face 'marginalia-symbol))
        ((pred numberp) (propertize (number-to-string val) 'face 'marginalia-number))
        (_ (let ((print-escape-newlines t)
                 (print-escape-control-characters t)
                 ;;(print-escape-multibyte t)
                 (print-level 3)
                 (print-length marginalia-field-width))
             (propertize
              (replace-regexp-in-string
               ;; `print-escape-control-characters' does not escape Unicode control characters.
               "[\x0-\x1F\x7f-\x9f\x061c\x200e\x200f\x202a-\x202e\x2066-\x2069]"
               (lambda (x) (format "\\x%x" (string-to-char x)))
               (prin1-to-string
                (if (stringp val)
                    ;; Get rid of string properties to save some of the precious space
                    (substring-no-properties
                     val 0
                     (min (length val) marginalia-field-width))
                  val))
               'fixedcase 'literal)
              'face
              (cond
               ((listp val) 'marginalia-list)
               ((stringp val) 'marginalia-string)
               (t 'marginalia-value))))))))))

(defun marginalia-annotate-variable (cand)
  "Annotate variable CAND with its documentation string."
  (when-let (sym (intern-soft cand))
    (marginalia--fields
     ((marginalia--symbol-class sym) :face 'marginalia-type)
     ((marginalia--variable-value sym) :truncate 0.5)
     ((documentation-property sym 'variable-documentation)
      :truncate 1.0 :face 'marginalia-documentation))))

(defun marginalia-annotate-environment-variable (cand)
  "Annotate environment variable CAND with its current value."
  (when-let (val (getenv cand))
    (marginalia--fields
     (val :truncate 1.0 :face 'marginalia-value))))

(defun marginalia-annotate-face (cand)
  "Annotate face CAND with its documentation string and face example."
  (when-let (sym (intern-soft cand))
    (marginalia--fields
     ;; HACK: Manual alignment to fix misalignment due to face
     ((concat marginalia--pangram #(" " 0 1 (display (space :align-to center))))
      :face sym)
     ((documentation-property sym 'face-documentation)
      :truncate 1.0 :face 'marginalia-documentation))))

(defun marginalia-annotate-color (cand)
  "Annotate face CAND with its documentation string and face example."
  (when-let (rgb (color-name-to-rgb cand))
    (pcase-let* ((`(,r ,g ,b) rgb)
                 (`(,h ,s ,l) (apply #'color-rgb-to-hsl rgb))
                 (cr (color-rgb-to-hex r 0 0))
                 (cg (color-rgb-to-hex 0 g 0))
                 (cb (color-rgb-to-hex 0 0 b))
                 (ch (apply #'color-rgb-to-hex (color-hsl-to-rgb h 1 0.5)))
                 (cs (apply #'color-rgb-to-hex (color-hsl-to-rgb h s 0.5)))
                 (cl (apply #'color-rgb-to-hex (color-hsl-to-rgb 0 0 l))))
      (marginalia--fields
       ("      " :face `(:background ,(apply #'color-rgb-to-hex rgb)))
       ((format
         "%s%s%s %s"
         (propertize "r" 'face `(:background ,cr :foreground ,(readable-foreground-color cr)))
         (propertize "g" 'face `(:background ,cg :foreground ,(readable-foreground-color cg)))
         (propertize "b" 'face `(:background ,cb :foreground ,(readable-foreground-color cb)))
         (color-rgb-to-hex r g b 2)))
       ((format
         "%s%s%s %3s° %3s%% %3s%%"
         (propertize "h" 'face `(:background ,ch :foreground ,(readable-foreground-color ch)))
         (propertize "s" 'face `(:background ,cs :foreground ,(readable-foreground-color cs)))
         (propertize "l" 'face `(:background ,cl :foreground ,(readable-foreground-color cl)))
         (round (* 360 h))
         (round (* 100 s))
         (round (* 100 l))))))))

(defun marginalia-annotate-char (cand)
  "Annotate character CAND with its general character category and character code."
  (when-let (char (char-from-name cand t))
    (marginalia--fields
     (:left char :format" (%c)" :face 'marginalia-char)
     (char :format "%06X" :face 'marginalia-number)
     ((char-code-property-description
       'general-category
       (get-char-code-property char 'general-category))
      :width 30 :face 'marginalia-documentation))))

(defun marginalia-annotate-minor-mode (cand)
  "Annotate minor-mode CAND with status and documentation string."
  (let* ((sym (intern-soft cand))
         (mode (if (and sym (boundp sym))
                   sym
                 (lookup-minor-mode-from-indicator cand)))
         (lighter (cdr (assq mode minor-mode-alist)))
         (lighter-str (and lighter (string-trim (format-mode-line (cons t lighter))))))
    (marginalia--fields
     ((if (and (boundp mode) (symbol-value mode))
          (propertize "On" 'face 'marginalia-on)
        (propertize "Off" 'face 'marginalia-off)) :width 3)
     ((if (local-variable-if-set-p mode) "Local" "Global") :width 6 :face 'marginalia-type)
     (lighter-str :width 20 :face 'marginalia-lighter)
     ((marginalia--function-doc mode)
      :truncate 1.0 :face 'marginalia-documentation))))

(defun marginalia-annotate-package (cand)
  "Annotate package CAND with its description summary."
  (when-let ((pkg-alist (bound-and-true-p package-alist))
             (name (replace-regexp-in-string "-[0-9\\.-]+\\'" "" cand))
             (pkg (intern-soft name))
             (desc (or (unless (equal name cand)
                         (cl-loop with version = (substring cand (1+ (length name)))
                                  for d in (alist-get pkg pkg-alist)
                                  if (equal (package-version-join (package-desc-version d)) version)
                                  return d))
                       ;; taken from `describe-package-1'
                       (car (alist-get pkg pkg-alist))
                       (if-let (built-in (assq pkg package--builtins))
                           (package--from-builtin built-in)
                         (car (alist-get pkg package-archive-contents))))))
    (marginalia--fields
     ((package-version-join (package-desc-version desc)) :truncate 16 :face 'marginalia-version)
     ((cond
       ((package-desc-archive desc) (propertize (package-desc-archive desc) 'face 'marginalia-archive))
       (t (propertize (or (package-desc-status desc) "orphan") 'face 'marginalia-installed))) :truncate 12)
     ((package-desc-summary desc) :truncate 1.0 :face 'marginalia-documentation))))

(defun marginalia--bookmark-type (bm)
  "Return bookmark type string of BM.
The string is transformed according to `marginalia--bookmark-type-transforms'."
  (let ((handler (or (bookmark-get-handler bm) 'bookmark-default-handler)))
    (and
     ;; Some libraries use lambda handlers instead of symbols. For
     ;; example the function `xwidget-webkit-bookmark-make-record' is
     ;; affected. I consider this bad style since then the lambda is
     ;; persisted.
     (symbolp handler)
     (or (get handler 'bookmark-handler-type)
         (let ((str (symbol-name handler)))
           (dolist (transformer marginalia--bookmark-type-transforms str)
             (when (string-match-p (car transformer) str)
               (setq str
                     (if (stringp (cdr transformer))
                         (replace-regexp-in-string (car transformer) (cdr transformer) str)
                       (funcall (cdr transformer) str))))))))))

(defun marginalia-annotate-bookmark (cand)
  "Annotate bookmark CAND with its file name and front context string."
  (when-let ((bm (assoc cand (bound-and-true-p bookmark-alist))))
    (let ((front (bookmark-get-front-context-string bm)))
      (marginalia--fields
       ((marginalia--bookmark-type bm) :width 10 :face 'marginalia-type)
       ((bookmark-get-filename bm)
        :truncate -0.5 :face 'marginalia-file-name)
       ((unless (or (not front) (equal front ""))
          (concat (string-clean-whitespace
                   (string-replace "\n" "\\n" front))
                  (marginalia--ellipsis)))
        :truncate -0.3 :face 'marginalia-documentation)))))

(defun marginalia-annotate-customize-group (cand)
  "Annotate customization group CAND with its documentation string."
  (marginalia--documentation (documentation-property (intern cand) 'group-documentation)))

(defun marginalia-annotate-input-method (cand)
  "Annotate input method CAND with its description."
  (marginalia--documentation (nth 4 (assoc cand input-method-alist))))

(defun marginalia-annotate-charset (cand)
  "Annotate charset CAND with its description."
  (marginalia--documentation (charset-description (intern cand))))

(defun marginalia-annotate-coding-system (cand)
  "Annotate coding system CAND with its description."
  (marginalia--documentation (coding-system-doc-string (intern cand))))

(defun marginalia--buffer-status (buffer)
  "Return the status of BUFFER as a string."
  (format-mode-line '((:propertize "%1*%1+%1@" face marginalia-modified)
                      marginalia-separator
                      (7 (:propertize "%I" face marginalia-size))
                      marginalia-separator
                      ;; InactiveMinibuffer has 18 letters, but there are longer names.
                      ;; For example Org-Agenda produces very long mode names.
                      ;; Therefore we have to truncate.
                      (20 (-20 (:propertize mode-name face marginalia-mode))))
                    nil nil buffer))

(defun marginalia--buffer-file (buffer)
  "Return the file or process name of BUFFER."
  (if-let (proc (get-buffer-process buffer))
      (format "(%s %s) %s"
              proc (process-status proc)
              (abbreviate-file-name (buffer-local-value 'default-directory buffer)))
    (abbreviate-file-name
     (or (cond
          ;; see ibuffer-buffer-file-name
          ((buffer-file-name buffer))
          ((when-let (dir (and (local-variable-p 'dired-directory buffer)
                               (buffer-local-value 'dired-directory buffer)))
             (expand-file-name (if (stringp dir) dir (car dir))
                               (buffer-local-value 'default-directory buffer))))
          ((local-variable-p 'list-buffers-directory buffer)
           (buffer-local-value 'list-buffers-directory buffer)))
         ""))))

(defun marginalia-annotate-buffer (cand)
  "Annotate buffer CAND with modification status, file name and major mode."
  (when-let (buffer (get-buffer cand))
    (marginalia--fields
     ((marginalia--buffer-status buffer))
     ((marginalia--buffer-file buffer)
      :truncate -0.5 :face 'marginalia-file-name))))

(defun marginalia--full-candidate (cand)
  "Return completion candidate CAND in full.
For some completion tables, the completion candidates offered are
meant to be only a part of the full minibuffer contents.  For
example, during file name completion the candidates are one path
component of a full file path."
  (if-let (win (active-minibuffer-window))
      (with-current-buffer (window-buffer win)
        (concat (let ((end (minibuffer-prompt-end)))
                  (buffer-substring-no-properties
                   end (+ end marginalia--base-position)))
                cand))
    ;; no minibuffer is active, trust that cand already conveys all
    ;; necessary information (there's not much else we can do)
    cand))

(defun marginalia--remote-protocol (path)
  "Return the remote protocol of PATH."
  (save-match-data
    (setq path (substitute-in-file-name path))
    (and (string-match "\\`/\\([^/|:]+\\):" path)
         (match-string 1 path))))

(defun marginalia--annotate-local-file (cand)
  "Annotate local file CAND."
  (when-let (attrs (ignore-errors
                     ;; may throw permission denied errors
                     (file-attributes (substitute-in-file-name
                                       (marginalia--full-candidate cand))
                                      'integer)))
    ;; HACK: Format differently accordingly to alignment, since the file owner
    ;; is usually not displayed. Otherwise we will see an excessive amount of
    ;; whitespace in front of the file permissions. Furthermore the alignment
    ;; in `consult-buffer' will look ugly. TODO: Find a better solution!
    (if (eq marginalia-align 'right)
        (marginalia--fields
         ;; File owner at the left
         ((marginalia--file-owner attrs) :face 'marginalia-file-owner)
         ((marginalia--file-modes attrs))
         ((marginalia--file-size attrs) :face 'marginalia-size :width -7)
         ((marginalia--time (file-attribute-modification-time attrs))
          :face 'marginalia-date :width -12))
      (marginalia--fields
       ((marginalia--file-modes attrs))
       ((marginalia--file-size attrs) :face 'marginalia-size :width -7)
       ((marginalia--time (file-attribute-modification-time attrs))
        :face 'marginalia-date :width -12)
       ;; File owner at the right
       ((marginalia--file-owner attrs) :face 'marginalia-file-owner)))))

(defun marginalia-annotate-file (cand)
  "Annotate file CAND with its size, modification time and other attributes.
These annotations are skipped for remote paths."
  (if-let (remote (or (marginalia--remote-protocol cand)
                      (when-let (win (active-minibuffer-window))
                        (with-current-buffer (window-buffer win)
                          (marginalia--remote-protocol (minibuffer-contents-no-properties))))))
      (marginalia--fields (remote :format "*%s*" :face 'marginalia-documentation))
    (marginalia--annotate-local-file cand)))

(defun marginalia--file-owner (attrs)
  "Return file owner given ATTRS."
  (let ((uid (file-attribute-user-id attrs))
        (gid (file-attribute-group-id attrs)))
    (when (or (/= (user-uid) uid) (/= (group-gid) gid))
      (format "%s:%s"
              (or (user-login-name uid) uid)
              (or (group-name gid) gid)))))

(defun marginalia--file-size (attrs)
  "Return formatted file size given ATTRS."
  (propertize (file-size-human-readable (file-attribute-size attrs))
              'help-echo (number-to-string (file-attribute-size attrs))))

(defun marginalia--file-modes (attrs)
  "Return fontified file modes given the ATTRS."
  ;; Without caching this can a be significant portion of the time
  ;; `marginalia-annotate-file' takes to execute. Caching improves performance
  ;; by about a factor of 20.
  (setq attrs (file-attribute-modes attrs))
  (or (car (member attrs marginalia--fontified-file-modes))
      (progn
        (setq attrs (substring attrs)) ;; copy because attrs is about to be modified
        (dotimes (i (length attrs))
          (put-text-property
           i (1+ i) 'face
           (pcase (aref attrs i)
             (?- 'marginalia-file-priv-no)
             (?d 'marginalia-file-priv-dir)
             (?l 'marginalia-file-priv-link)
             (?r 'marginalia-file-priv-read)
             (?w 'marginalia-file-priv-write)
             (?x 'marginalia-file-priv-exec)
             ((or ?s ?S ?t ?T) 'marginalia-file-priv-other)
             (_ 'marginalia-file-priv-rare))
           attrs))
        (push attrs marginalia--fontified-file-modes)
        attrs)))

(defconst marginalia--time-relative
  `((100 "sec" 1)
    (,(* 60 100) "min" 60.0)
    (,(* 3600 30) "hour" 3600.0)
    (,(* 3600 24 400) "day" ,(* 3600.0 24.0))
    (nil "year" ,(* 365.25 24 3600)))
  "Formatting used by the function `marginalia--time-relative'.")

;; Taken from `seconds-to-string'.
(defun marginalia--time-relative (time)
  "Format TIME as a relative age."
  (setq time (max 0 (float-time (time-since time))))
  (let ((sts marginalia--time-relative) here)
    (while (and (car (setq here (pop sts))) (<= (car here) time)))
    (setq time (round time (caddr here)))
    (format "%s %s%s ago" time (cadr here) (if (= time 1) "" "s"))))

(defun marginalia--time-absolute (time)
  "Format TIME as an absolute age."
  (let ((system-time-locale "C"))
    (format-time-string
     (if (> (decoded-time-year (decode-time (current-time)))
            (decoded-time-year (decode-time time)))
         " %Y %b %d"
       "%b %d %H:%M")
     time)))

(defun marginalia--time (time)
  "Format file age TIME, suitably for use in annotations."
  (propertize
   (if (< (float-time (time-since time)) marginalia-max-relative-age)
       (marginalia--time-relative time)
     (marginalia--time-absolute time))
   'help-echo (format-time-string "%Y-%m-%d %T" time)))

(defvar-local marginalia--project-root 'unset)
(defun marginalia--project-root ()
  "Return project root."
  (with-current-buffer
      (if-let (win (active-minibuffer-window))
          (window-buffer win)
        (current-buffer))
    (when (eq marginalia--project-root 'unset)
      (setq marginalia--project-root
            (or (let ((prompt (minibuffer-prompt)))
                  (and (string-match
                        "\\`\\(?:Dired\\|Find file\\) in \\(.*\\): \\'"
                        prompt)
                       (match-string 1 prompt)))
                (when-let (proj (project-current))
                  (cond
                   ((fboundp 'project-root) (project-root proj))
                   ((fboundp 'project-roots) (car (project-roots proj))))))))
    marginalia--project-root))

(defun marginalia-annotate-project-file (cand)
  "Annotate file CAND with its size, modification time and other attributes."
  ;; Absolute project directories also report project-file category
  (if (file-name-absolute-p cand)
      (marginalia-annotate-file cand)
    (when-let (root (marginalia--project-root))
      (marginalia-annotate-file (expand-file-name cand root)))))

(defvar-local marginalia--library-cache nil)
(defun marginalia--library-cache ()
  "Return library cache hash table."
  (with-current-buffer
      (if-let (win (active-minibuffer-window))
          (window-buffer win)
        (current-buffer))
    ;; `locate-file' and `locate-library' are bottlenecks for the
    ;; annotator. Therefore we compute all the library paths first.
    (unless marginalia--library-cache
      (setq marginalia--library-cache (make-hash-table :test #'equal))
      ;; Search in reverse because of shadowing
      (dolist (dir (reverse load-path))
        (dolist (file (ignore-errors
                        (directory-files dir 'full
                                         "\\.el\\(?:\\.gz\\)?\\'")))
          (puthash (marginalia--library-name file)
                   file marginalia--library-cache))))
    marginalia--library-cache))

(defun marginalia--library-name (file)
  "Get name of library FILE."
  (replace-regexp-in-string "\\(\\.gz\\|\\.elc?\\)+\\'" ""
                            (file-name-nondirectory file)))

(defun marginalia--library-doc (file)
  "Return library documentation string for FILE."
  (let ((doc (get-text-property 0 'marginalia--library-doc file)))
    (unless doc
      ;; Extract documentation string. We cannot use `lm-summary' here,
      ;; since it decompresses the whole file, which is slower.
      (setq doc (or (ignore-errors
                      (let ((shell-file-name "sh")
                            (shell-command-switch "-c"))
                        (shell-command-to-string
                         (format (if (string-suffix-p ".gz" file)
                                     "gzip -c -q -d %s | head -n1"
                                   "head -n1 %s")
                                 (shell-quote-argument file)))))
                    ""))
      (cond
       ((string-match "\\`(define-package\\s-+\"\\([^\"]+\\)\"" doc)
        (setq doc (format "Generated package description from %s.el"
                          (match-string 1 doc))))
       ((string-match "\\`;+\\s-*" doc)
        (setq doc (substring doc (match-end 0)))
        (when (string-match "\\`[^ \t]+\\s-+-+\\s-+" doc)
          (setq doc (substring doc (match-end 0))))
        (when (string-match "\\s-*-\\*-" doc)
          (setq doc (substring doc 0 (match-beginning 0)))))
       (t (setq doc "")))
      ;; Add the documentation string to the cache
      (put-text-property 0 1 'marginalia--library-doc doc file))
    doc))

(defun marginalia-annotate-library (cand)
  "Annotate library CAND with documentation and path."
  (setq cand (marginalia--library-name cand))
  (when-let (file (gethash cand (marginalia--library-cache)))
    (marginalia--fields
     ;; Display if the corresponding feature is loaded.
     ;; feature/=library file, but better than nothing.
     ((when-let (sym (intern-soft cand))
        (when (memq sym features)
          (propertize "Loaded" 'face 'marginalia-on)))
      :width 8)
     ((marginalia--library-doc file)
      :truncate 1.0 :face 'marginalia-documentation)
     ((abbreviate-file-name (file-name-directory file))
      :truncate -0.5 :face 'marginalia-file-name))))

(defun marginalia-annotate-tab (cand)
  "Annotate named tab CAND with tab index, window and buffer information."
  (when-let ((tabs (funcall tab-bar-tabs-function))
             (index (seq-position
                     tabs nil
                     (lambda (tab _) (equal (alist-get 'name tab) cand)))))
    (let* ((tab (nth index tabs))
           (ws (alist-get 'ws tab))
           (bufs (window-state-buffers ws)))
      ;; NOTE: When the buffer key is present in the window state
      ;; it is added in front of the window buffer list and gets duplicated.
      (when (cadr (assq 'buffer ws)) (pop bufs))
      (marginalia--fields
       (:left index :format " (%s)" :face 'marginalia-key)
       ((if (eq (car tab) 'current-tab)
            (length (window-list nil 'no-minibuf))
          (length bufs))
        :format "win:%s" :face 'marginalia-size)
       ((or (alist-get 'group tab) 'none)
        :format "group:%s" :face 'marginalia-type :truncate 20)
       ((if (eq (car tab) 'current-tab)
            "(current tab)"
          (string-join bufs " "))
        :face 'marginalia-documentation)))))

(defun marginalia-classify-by-command-name ()
  "Lookup category for current command."
  (and marginalia--command
       (alist-get marginalia--command marginalia-command-categories)))

(defun marginalia-classify-original-category ()
  "Return original category reported by completion metadata."
  ;; NOTE: Use `alist-get' instead of `completion-metadata-get' to bypass our
  ;; `marginalia--completion-metadata-get' advice!
  (when-let (cat (alist-get 'category marginalia--metadata))
    ;; Ignore Emacs 28 symbol-help category in order to ensure that the
    ;; categories are refined to our categories function and variable.
    (and (not (eq cat 'symbol-help)) cat)))

(defun marginalia-classify-symbol ()
  "Determine if currently completing symbols."
  (when-let (mct minibuffer-completion-table)
    (when (or (eq mct 'help--symbol-completion-table)
              (obarrayp mct)
              (and (not (functionp mct)) (consp mct) (symbolp (car mct)))) ; assume list of symbols
      'symbol)))

(defun marginalia-classify-by-prompt ()
  "Determine category by matching regexps against the minibuffer prompt.
This runs through the `marginalia-prompt-categories' alist
looking for a regexp that matches the prompt."
  (when-let (prompt (minibuffer-prompt))
    (setq prompt
          (replace-regexp-in-string "(.*?default.*?)\\|\\[.*?\\]" "" prompt))
    (cl-loop for (regexp . category) in marginalia-prompt-categories
             when (string-match-p regexp prompt)
             return category)))

(defun marginalia--cache-reset (&rest _)
  "Reset the cache."
  (setq marginalia--cache (and marginalia--cache (> marginalia--cache-size 0)
                               (cons nil (make-hash-table :test #'equal
                                                          :size marginalia--cache-size)))))

(defun marginalia--cached (cache fun key)
  "Cached application of function FUN with KEY.
The CACHE keeps around the last `marginalia--cache-size' computed
annotations.  The cache is mainly useful when scrolling in
completion UIs like Vertico or Icomplete."
  (if cache
      (let ((ht (cdr cache)))
        (or (gethash key ht)
            (let ((val (funcall fun key)))
              (push key (car cache))
              (puthash key val ht)
              (when (>= (hash-table-count ht) marginalia--cache-size)
                (let ((end (last (car cache) 2)))
                  (remhash (cadr end) ht)
                  (setcdr end nil)))
              val)))
    (funcall fun key)))

(defun marginalia--align (cands)
  "Align annotations of CANDS according to `marginalia-align'."
  (cl-loop
   for (cand . ann) in cands do
   (when-let (align (text-property-any 0 (length ann) 'marginalia--align t ann))
     (setq marginalia--cand-width-max
           (max marginalia--cand-width-max
                (* (ceiling (+ (string-width cand)
                               (compat-call string-width ann 0 align))
                            marginalia--cand-width-step)
                   marginalia--cand-width-step)))))
  (cl-loop
   for (cand . ann) in cands collect
   (progn
     (when-let (align (text-property-any 0 (length ann) 'marginalia--align t ann))
       (put-text-property
        align (1+ align) 'display
        `(space :align-to
                ,(pcase-exhaustive marginalia-align
                   ('center `(+ center ,marginalia-align-offset))
                   ('left `(+ left ,(+ marginalia-align-offset marginalia--cand-width-max)))
                   ('right `(+ right ,(+ marginalia-align-offset 1
                                         (- (compat-call string-width ann 0 align)
                                            (string-width ann)))))))
        ann))
     (list cand "" ann))))

(defun marginalia--affixate (metadata annotator cands)
  "Affixate CANDS given METADATA and Marginalia ANNOTATOR."
  ;; Compute minimum width of windows, which display the minibuffer.
  ;; vertico-buffer displays the minibuffer in different windows. We may want
  ;; to generalize this and detect other types of completion buffers, e.g.,
  ;; Embark Collect or the default completion buffer.
  (let* ((width (cl-loop for win in (get-buffer-window-list) minimize (window-width win)))
         (marginalia-field-width (min (/ width 2) marginalia-field-width))
         (marginalia--metadata metadata)
         (cache marginalia--cache))
    (marginalia--align
     ;; Run the annotators in the original window. `with-selected-window'
     ;; is necessary because of `lookup-minor-mode-from-indicator'.
     ;; Otherwise it would suffice to only change the current buffer. We
     ;; need the `selected-window' fallback for Embark Occur.
     (with-selected-window (or (minibuffer-selected-window) (selected-window))
       (cl-loop for cand in cands collect
                (let ((ann (or (marginalia--cached cache annotator cand) "")))
                  (cons cand (if (string-blank-p ann) "" ann))))))))

(defun marginalia--completion-metadata-get (metadata prop)
  "Meant as :before-until advice for `completion-metadata-get'.
METADATA is the metadata.
PROP is the property which is looked up."
  (pcase prop
    ('annotation-function
     ;; We do want the advice triggered for `completion-metadata-get'.
     (when-let ((cat (completion-metadata-get metadata 'category))
                (annotator (marginalia--annotator cat)))
       (lambda (cand)
         (let ((ann (caddar (marginalia--affixate metadata annotator (list cand)))))
           (and (not (equal ann "")) ann)))))
    ('affixation-function
     ;; We do want the advice triggered for `completion-metadata-get'.
     (when-let ((cat (completion-metadata-get metadata 'category))
                (annotator (marginalia--annotator cat)))
       (apply-partially #'marginalia--affixate metadata annotator)))
    ('category
     ;; Find the completion category by trying each of our classifiers.
     ;; Store the metadata for `marginalia-classify-original-category'.
     (let ((marginalia--metadata metadata))
       (run-hook-with-args-until-success 'marginalia-classifiers)))))

(defun marginalia--minibuffer-setup ()
  "Setup the minibuffer for Marginalia.
Remember `this-command' for `marginalia-classify-by-command-name'."
  (setq marginalia--cache t marginalia--command this-command)
  ;; Reset cache if window size changes, recompute alignment
  (add-hook 'window-state-change-hook #'marginalia--cache-reset nil 'local)
  (marginalia--cache-reset))

(defun marginalia--base-position (completions)
  "Record the base position of COMPLETIONS."
  ;; NOTE: As a small optimization we track the base position only for file
  ;; completions, since `marginalia--full-candidate' is currently used only by
  ;; the file annotation function.
  (when minibuffer-completing-file-name
    (let ((base (or (cdr (last completions)) 0)))
      (unless (= marginalia--base-position base)
        (marginalia--cache-reset)
        (setq marginalia--base-position base
              marginalia--cand-width-max (default-value 'marginalia--cand-width-max)))))
  completions)

;;;###autoload
(define-minor-mode marginalia-mode
  "Annotate completion candidates with richer information."
  :global t :group 'marginalia
  (if marginalia-mode
      (progn
        ;; Remember `this-command' in order to select the annotation function.
        (add-hook 'minibuffer-setup-hook #'marginalia--minibuffer-setup)
        ;; Replace the metadata function.
        (advice-add #'completion-metadata-get :before-until #'marginalia--completion-metadata-get)
        ;; Record completion base position, for `marginalia--full-candidate'
        (advice-add #'completion-all-completions :filter-return #'marginalia--base-position))
    (advice-remove #'completion-all-completions #'marginalia--base-position)
    (advice-remove #'completion-metadata-get #'marginalia--completion-metadata-get)
    (remove-hook 'minibuffer-setup-hook #'marginalia--minibuffer-setup)))

;;;###autoload
(defun marginalia-cycle ()
  "Cycle between annotators in `marginalia-annotator-registry'."
  (interactive)
  (if-let ((win (active-minibuffer-window))
           (buf (window-buffer win)))
      (with-current-buffer buf
        (let* ((pt (max 0 (- (point) (minibuffer-prompt-end))))
               (metadata (completion-metadata (buffer-substring-no-properties
                                               (minibuffer-prompt-end)
                                               (+ (minibuffer-prompt-end) pt))
                                              minibuffer-completion-table
                                              minibuffer-completion-predicate))
               (cat (completion-metadata-get metadata 'category)))
          (unless cat
            (user-error "Marginalia: Unknown completion category"))
          (setq cat (assq cat marginalia-annotator-registry))
          (unless cat
            (user-error "Marginalia: No annotators found"))
          (marginalia--cache-reset)
          (setcdr cat (append (cddr cat) (list (cadr cat))))
          ;; When the builtin annotator is selected and no builtin function is
          ;; available, skip to the next annotator. Note that we cannot use
          ;; `completion-metadata-get' to access the metadata since we must
          ;; bypass the `marginalia--completion-metadata-get' advice.
          (when (and (eq (cadr cat) 'builtin)
                     (not (assq 'annotation-function metadata))
                     (not (assq 'affixation-function metadata))
                     (not (plist-get completion-extra-properties :annotation-function))
                     (not (plist-get completion-extra-properties :affixation-function)))
            (setcdr cat (append (cddr cat) (list (cadr cat)))))
          (message "Marginalia: Use annotator `%s' for category `%s'" (cadr cat) (car cat))))
    (user-error "Marginalia: No active minibuffer")))

(provide 'marginalia)
;;; marginalia.el ends here