lisp/tmm.el

   1 ;;; tmm.el --- text mode access to menu-bar  -*- lexical-binding: t -*-
   2
   3 ;; Copyright (C) 1994-1996, 2000-2017 Free Software Foundation, Inc.
   4
   5 ;; Author: Ilya Zakharevich <ilya@math.mps.ohio-state.edu>
   6 ;; Maintainer: emacs-devel@gnu.org
   7 ;; Keywords: convenience
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software: you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation, either version 3 of the License, or
  14 ;; (at your option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; This package provides text mode access to the menu bar.
  27
  28 ;;; Code:
  29
  30 (require 'electric)
  31
  32 (defgroup tmm nil
  33   "Text mode access to menu-bar."
  34   :prefix "tmm-"
  35   :group 'menu)
  36
  37 ;;; The following will be localized, added only to pacify the compiler.
  38 (defvar tmm-short-cuts)
  39 (defvar tmm-old-mb-map nil)
  40 (defvar tmm-c-prompt nil)
  41 (defvar tmm-km-list)
  42 (defvar tmm-next-shortcut-digit)
  43 (defvar tmm-table-undef)
  44
  45 ;;;###autoload (define-key global-map "\M-`" 'tmm-menubar)
  46 ;;;###autoload (define-key global-map [menu-bar mouse-1] 'tmm-menubar-mouse)
  47
  48 ;;;###autoload
  49 (defun tmm-menubar (&optional x-position)
  50   "Text-mode emulation of looking and choosing from a menubar.
  51 See the documentation for `tmm-prompt'.
  52 X-POSITION, if non-nil, specifies a horizontal position within the menu bar;
  53 we make that menu bar item (the one at that position) the default choice.
  54
  55 Note that \\[menu-bar-open] by default drops down TTY menus; if you want it
  56 to invoke `tmm-menubar' instead, customize the variable
  57 `tty-menu-open-use-tmm' to a non-nil value."
  58   (interactive)
  59   (run-hooks 'menu-bar-update-hook)
  60   ;; Obey menu-bar-final-items; put those items last.
  61   (let ((menu-bar '())
  62         (menu-end '())
  63         menu-bar-item)
  64     (map-keymap
  65      (lambda (key binding)
  66        (push (cons key binding)
  67              ;; If KEY is the name of an item that we want to put last,
  68              ;; move it to the end.
  69              (if (memq key menu-bar-final-items)
  70                  menu-end
  71                menu-bar)))
  72      (tmm-get-keybind [menu-bar]))
  73     (setq menu-bar `(keymap ,@(nreverse menu-bar) ,@(nreverse menu-end)))
  74     (if x-position
  75         (let ((column 0)
  76               prev-key)
  77           (catch 'done
  78             (map-keymap
  79              (lambda (key binding)
  80                (when (> column x-position)
  81                  (setq menu-bar-item prev-key)
  82                  (throw 'done nil))
  83                (setq prev-key key)
  84                (pcase binding
  85                  ((or `(,(and (pred stringp) name) . ,_) ;Simple menu item.
  86                       `(menu-item ,name ,_cmd            ;Extended menu item.
  87                         . ,(and props
  88                                 (guard (let ((visible
  89                                               (plist-get props :visible)))
  90                                          (or (null visible)
  91                                              (eval visible)))))))
  92                   (setq column (+ column (length name) 1)))))
  93              menu-bar))))
  94     (tmm-prompt menu-bar nil menu-bar-item)))
  95
  96 ;;;###autoload
  97 (defun tmm-menubar-mouse (event)
  98   "Text-mode emulation of looking and choosing from a menubar.
  99 This command is used when you click the mouse in the menubar
 100 on a console which has no window system but does have a mouse.
 101 See the documentation for `tmm-prompt'."
 102   (interactive "e")
 103   (tmm-menubar (car (posn-x-y (event-start event)))))
 104
 105 (defcustom tmm-mid-prompt "==>"
 106   "String to insert between shortcut and menu item.
 107 If nil, there will be no shortcuts.  It should not consist only of spaces,
 108 or else the correct item might not be found in the `*Completions*' buffer."
 109   :type 'string
 110   :group 'tmm)
 111
 112 (defvar tmm-mb-map nil
 113   "A place to store minibuffer map.")
 114
 115 (defcustom tmm-completion-prompt
 116   "Press PageUp key to reach this buffer from the minibuffer.
 117 Alternatively, you can use Up/Down keys (or your History keys) to change
 118 the item in the minibuffer, and press RET when you are done, or press the
 119 marked letters to pick up your choice.  Type C-g or ESC ESC ESC to cancel.
 120 "
 121   "Help text to insert on the top of the completion buffer.
 122 To save space, you can set this to nil,
 123 in which case the standard introduction text is deleted too."
 124   :type '(choice string (const nil))
 125   :group 'tmm)
 126
 127 (defcustom tmm-shortcut-style '(downcase upcase)
 128   "What letters to use as menu shortcuts.
 129 Must be either one of the symbols `downcase' or `upcase',
 130 or else a list of the two in the order you prefer."
 131   :type '(choice (const downcase)
 132                  (const upcase)
 133                  (repeat (choice (const downcase) (const upcase))))
 134   :group 'tmm)
 135
 136 (defcustom tmm-shortcut-words 2
 137   "How many successive words to try for shortcuts, nil means all.
 138 If you use only one of `downcase' or `upcase' for `tmm-shortcut-style',
 139 specify nil for this variable."
 140   :type '(choice integer (const nil))
 141   :group 'tmm)
 142
 143 (defface tmm-inactive
 144   '((t :inherit shadow))
 145   "Face used for inactive menu items."
 146   :group 'tmm)
 147
 148 (defun tmm--completion-table (items)
 149   (lambda (string pred action)
 150     (if (eq action 'metadata)
 151         '(metadata (display-sort-function . identity))
 152       (complete-with-action action items string pred))))
 153
 154 (defvar tmm--history nil)
 155
 156 ;;;###autoload
 157 (defun tmm-prompt (menu &optional in-popup default-item)
 158   "Text-mode emulation of calling the bindings in keymap.
 159 Creates a text-mode menu of possible choices.  You can access the elements
 160 in the menu in two ways:
 161    *)  via history mechanism from minibuffer;
 162    *)  Or via completion-buffer that is automatically shown.
 163 The last alternative is currently a hack, you cannot use mouse reliably.
 164
 165 MENU is like the MENU argument to `x-popup-menu': either a
 166 keymap or an alist of alists.
 167 DEFAULT-ITEM, if non-nil, specifies an initial default choice.
 168 Its value should be an event that has a binding in MENU."
 169   ;; If the optional argument IN-POPUP is t,
 170   ;; then MENU is an alist of elements of the form (STRING . VALUE).
 171   ;; That is used for recursive calls only.
 172   (let ((gl-str "Menu bar")  ;; The menu bar itself is not a menu keymap
 173                                         ; so it doesn't have a name.
 174         tmm-km-list out history-len tmm-table-undef tmm-c-prompt
 175         tmm-old-mb-map tmm-short-cuts
 176         chosen-string choice
 177         (not-menu (not (keymapp menu))))
 178     (run-hooks 'activate-menubar-hook)
 179     ;; Compute tmm-km-list from MENU.
 180     ;; tmm-km-list is an alist of (STRING . MEANING).
 181     ;; It has no other elements.
 182     ;; The order of elements in tmm-km-list is the order of the menu bar.
 183     (if (not not-menu)
 184         (map-keymap (lambda (k v) (tmm-get-keymap (cons k v))) menu)
 185       (dolist (elt menu)
 186         (cond
 187          ((stringp elt) (setq gl-str elt))
 188          ((listp elt) (tmm-get-keymap elt not-menu))
 189          ((vectorp elt)
 190           (dotimes (i (length elt))
 191             (tmm-get-keymap (cons i (aref elt i)) not-menu))))))
 192     ;; Choose an element of tmm-km-list; put it in choice.
 193     (if (and not-menu (= 1 (length tmm-km-list)))
 194         ;; If this is the top-level of an x-popup-menu menu,
 195         ;; and there is just one pane, choose that one silently.
 196         ;; This way we only ask the user one question,
 197         ;; for which element of that pane.
 198         (setq choice (cdr (car tmm-km-list)))
 199       (unless tmm-km-list
 200         (error "Empty menu reached"))
 201       (and tmm-km-list
 202            (let ((index-of-default 0))
 203              (if tmm-mid-prompt
 204                  (setq tmm-km-list (tmm-add-shortcuts tmm-km-list))
 205                t)
 206              ;; Find the default item's index within the menu bar.
 207              ;; We use this to decide the initial minibuffer contents
 208              ;; and initial history position.
 209              (if default-item
 210                  (let ((tail menu) visible)
 211                    (while (and tail
 212                                (not (eq (car-safe (car tail)) default-item)))
 213                      ;; Be careful to count only the elements of MENU
 214                      ;; that actually constitute menu bar items.
 215                      (if (and (consp (car tail))
 216                               (or (stringp (car-safe (cdr (car tail))))
 217                                   (and
 218                                    (eq (car-safe (cdr (car tail))) 'menu-item)
 219                                    (progn
 220                                      (setq visible
 221                                            (plist-get
 222                                             (nthcdr 4 (car tail)) :visible))
 223                                      (or (not visible) (eval visible))))))
 224                          (setq index-of-default (1+ index-of-default)))
 225                      (setq tail (cdr tail)))))
 226              (let ((prompt (concat "^." (regexp-quote tmm-mid-prompt))))
 227                (setq tmm--history
 228                      (reverse (delq nil
 229                                     (mapcar
 230                                      (lambda (elt)
 231                                        (if (string-match prompt (car elt))
 232                                            (car elt)))
 233                                      tmm-km-list)))))
 234              (setq history-len (length tmm--history))
 235              (setq tmm--history (append tmm--history tmm--history
 236                                         tmm--history tmm--history))
 237              (setq tmm-c-prompt (nth (- history-len 1 index-of-default)
 238                                      tmm--history))
 239              (setq out
 240                    (if default-item
 241                        (car (nth index-of-default tmm-km-list))
 242                      (minibuffer-with-setup-hook #'tmm-add-prompt
 243                        ;; tmm-km-list is reversed, because history
 244                        ;; needs it in LIFO order.  But completion
 245                        ;; needs it in non-reverse order, so that the
 246                        ;; menu items are displayed as completion
 247                        ;; candidates in the order they are shown on
 248                        ;; the menu bar.  So pass completing-read the
 249                        ;; reversed copy of the list.
 250                        (completing-read-default
 251                         (concat gl-str
 252                                 " (up/down to change, PgUp to menu): ")
 253                         (tmm--completion-table (reverse tmm-km-list)) nil t nil
 254                         (cons 'tmm--history
 255                               (- (* 2 history-len) index-of-default))))))))
 256       (setq choice (cdr (assoc out tmm-km-list)))
 257       (and (null choice)
 258            (string-prefix-p tmm-c-prompt out)
 259            (setq out (substring out (length tmm-c-prompt))
 260                  choice (cdr (assoc out tmm-km-list))))
 261       (and (null choice) out
 262            (setq out (try-completion out tmm-km-list)
 263                  choice (cdr (assoc  out tmm-km-list)))))
 264     ;; CHOICE is now (STRING . MEANING).  Separate the two parts.
 265     (setq chosen-string (car choice))
 266     (setq choice (cdr choice))
 267     (cond (in-popup
 268            ;; We just did the inner level of a -popup menu.
 269            choice)
 270           ;; We just did the outer level.  Do the inner level now.
 271           (not-menu (tmm-prompt choice t))
 272           ;; We just handled a menu keymap and found another keymap.
 273           ((keymapp choice)
 274            (if (symbolp choice)
 275                (setq choice (indirect-function choice)))
 276            (condition-case nil
 277                (require 'mouse)
 278              (error nil))
 279            (tmm-prompt choice))
 280           ;; We just handled a menu keymap and found a command.
 281           (choice
 282            (if chosen-string
 283                (progn
 284                  (setq last-command-event chosen-string)
 285                  (call-interactively choice))
 286              choice)))))
 287
 288 (defun tmm-add-shortcuts (list)
 289   "Add shortcuts to cars of elements of the list.
 290 Takes a list of lists with a string as car, returns list with
 291 shortcuts added to these cars.
 292 Stores a list of all the shortcuts in the free variable `tmm-short-cuts'."
 293   (let ((tmm-next-shortcut-digit ?0))
 294     (mapcar 'tmm-add-one-shortcut (reverse list))))
 295
 296 (defsubst tmm-add-one-shortcut (elt)
 297 ;; uses the free vars tmm-next-shortcut-digit and tmm-short-cuts
 298   (cond
 299    ((eq (cddr elt) 'ignore)
 300     (cons (concat " " (make-string (length tmm-mid-prompt) ?\-)
 301                   (car elt))
 302           (cdr elt)))
 303    (t
 304     (let* ((str (car elt))
 305            (paren (string-match "(" str))
 306            (pos 0) (word 0) char)
 307       (catch 'done                             ; ??? is this slow?
 308         (while (and (or (not tmm-shortcut-words)   ; no limit on words
 309                         (< word tmm-shortcut-words)) ; try n words
 310                     (setq pos (string-match "\\w+" str pos)) ; get next word
 311                     (not (and paren (> pos paren)))) ; don't go past "(binding.."
 312           (if (or (= pos 0)
 313                   (/= (aref str (1- pos)) ?.)) ; avoid file extensions
 314               (let ((shortcut-style
 315                      (if (listp tmm-shortcut-style) ; convert to list
 316                          tmm-shortcut-style
 317                        (list tmm-shortcut-style))))
 318                 (while shortcut-style ; try upcase and downcase variants
 319                   (setq char (funcall (car shortcut-style) (aref str pos)))
 320                   (if (not (memq char tmm-short-cuts)) (throw 'done char))
 321                   (setq shortcut-style (cdr shortcut-style)))))
 322           (setq word (1+ word))
 323           (setq pos (match-end 0)))
 324         (while (<= tmm-next-shortcut-digit ?9) ; no letter shortcut, pick a digit
 325           (setq char tmm-next-shortcut-digit)
 326           (setq tmm-next-shortcut-digit (1+ tmm-next-shortcut-digit))
 327           (if (not (memq char tmm-short-cuts)) (throw 'done char)))
 328         (setq char nil))
 329       (if char (setq tmm-short-cuts (cons char tmm-short-cuts)))
 330       (cons (concat (if char (concat (char-to-string char) tmm-mid-prompt)
 331                       ;; keep them lined up in columns
 332                       (make-string (1+ (length tmm-mid-prompt)) ?\s))
 333                     str)
 334             (cdr elt))))))
 335
 336 ;; This returns the old map.
 337 (defun tmm-define-keys (minibuffer)
 338   (let ((map (make-sparse-keymap)))
 339     (suppress-keymap map t)
 340     (dolist (c tmm-short-cuts)
 341       (if (listp tmm-shortcut-style)
 342           (define-key map (char-to-string c) 'tmm-shortcut)
 343         ;; only one kind of letters are shortcuts, so map both upcase and
 344         ;; downcase input to the same
 345         (define-key map (char-to-string (downcase c)) 'tmm-shortcut)
 346         (define-key map (char-to-string (upcase c)) 'tmm-shortcut)))
 347     (if minibuffer
 348         (progn
 349           (define-key map [pageup] 'tmm-goto-completions)
 350           (define-key map [prior] 'tmm-goto-completions)
 351           (define-key map "\ev" 'tmm-goto-completions)
 352           (define-key map "\C-n" 'next-history-element)
 353           (define-key map "\C-p" 'previous-history-element)))
 354     (prog1 (current-local-map)
 355       (use-local-map (append map (current-local-map))))))
 356
 357 (defun tmm-completion-delete-prompt ()
 358   (with-current-buffer standard-output
 359   (goto-char (point-min))
 360     (delete-region (point) (search-forward "Possible completions are:\n"))))
 361
 362 (defun tmm-remove-inactive-mouse-face ()
 363   "Remove the mouse-face property from inactive menu items."
 364   (let ((inhibit-read-only t)
 365         (inactive-string
 366          (concat " " (make-string (length tmm-mid-prompt) ?\-)))
 367         next)
 368     (save-excursion
 369       (goto-char (point-min))
 370       (while (not (eobp))
 371         (setq next (next-single-char-property-change (point) 'mouse-face))
 372         (when (looking-at inactive-string)
 373           (remove-text-properties (point) next '(mouse-face))
 374           (add-text-properties (point) next '(face tmm-inactive)))
 375         (goto-char next)))
 376     (set-buffer-modified-p nil)))
 377
 378 (defun tmm-add-prompt ()
 379   (unless tmm-c-prompt
 380     (error "No active menu entries"))
 381   (setq tmm-old-mb-map (tmm-define-keys t))
 382   (or tmm-completion-prompt
 383       (add-hook 'completion-setup-hook
 384                 'tmm-completion-delete-prompt 'append))
 385   (unwind-protect
 386       (minibuffer-completion-help)
 387     (remove-hook 'completion-setup-hook 'tmm-completion-delete-prompt))
 388   (with-current-buffer "*Completions*"
 389     (tmm-remove-inactive-mouse-face)
 390     (when tmm-completion-prompt
 391       (let ((inhibit-read-only t)
 392             (window (get-buffer-window "*Completions*")))
 393         (goto-char (point-min))
 394         (insert tmm-completion-prompt)
 395         (when window
 396           ;; Try to show everything just inserted and preserve height of
 397           ;; *Completions* window.  This should fix a behavior described
 398           ;; in Bug#1291.
 399           (fit-window-to-buffer window nil nil nil nil t)))))
 400   (insert tmm-c-prompt))
 401
 402 (defun tmm-shortcut ()
 403   "Choose the shortcut that the user typed."
 404   (interactive)
 405   (let ((c last-command-event) s)
 406     (if (symbolp tmm-shortcut-style)
 407         (setq c (funcall tmm-shortcut-style c)))
 408     (if (memq c tmm-short-cuts)
 409         (if (equal (buffer-name) "*Completions*")
 410             (progn
 411               (goto-char (point-min))
 412               (re-search-forward
 413                (concat "\\(^\\|[ \t]\\)" (char-to-string c) tmm-mid-prompt))
 414               (choose-completion))
 415           ;; In minibuffer
 416           (delete-region (minibuffer-prompt-end) (point-max))
 417           (dolist (elt tmm-km-list)
 418             (if (string=
 419                  (substring (car elt) 0
 420                             (min (1+ (length tmm-mid-prompt))
 421                                  (length (car elt))))
 422                  (concat (char-to-string c) tmm-mid-prompt))
 423                 (setq s (car elt))))
 424           (insert s)
 425           (exit-minibuffer)))))
 426
 427 (defun tmm-goto-completions ()
 428   "Jump to the completions buffer."
 429   (interactive)
 430   (let ((prompt-end (minibuffer-prompt-end)))
 431     (setq tmm-c-prompt (buffer-substring prompt-end (point-max)))
 432     ;; FIXME: Why?
 433     (delete-region prompt-end (point-max)))
 434   (switch-to-buffer-other-window "*Completions*")
 435   (search-forward tmm-c-prompt)
 436   (search-backward tmm-c-prompt))
 437
 438 (defun tmm-get-keymap (elt &optional in-x-menu)
 439   "Prepend (DOCSTRING EVENT BINDING) to free variable `tmm-km-list'.
 440 The values are deduced from the argument ELT, that should be an
 441 element of keymap, an `x-popup-menu' argument, or an element of
 442 `x-popup-menu' argument (when IN-X-MENU is not-nil).
 443 This function adds the element only if it is not already present.
 444 It uses the free variable `tmm-table-undef' to keep undefined keys."
 445   (let (km str plist filter visible enable (event (car elt)))
 446     (setq elt (cdr elt))
 447     (if (eq elt 'undefined)
 448         (setq tmm-table-undef (cons (cons event nil) tmm-table-undef))
 449       (unless (assoc event tmm-table-undef)
 450         (cond ((if (listp elt)
 451                    (or (keymapp elt) (eq (car elt) 'lambda))
 452                  (and (symbolp elt) (fboundp elt)))
 453                (setq km elt))
 454
 455               ((if (listp (cdr-safe elt))
 456                    (or (keymapp (cdr-safe elt))
 457                        (eq (car (cdr-safe elt)) 'lambda))
 458                  (and (symbolp (cdr-safe elt)) (fboundp (cdr-safe elt))))
 459                (setq km (cdr elt))
 460                (and (stringp (car elt)) (setq str (car elt))))
 461
 462               ((if (listp (cdr-safe (cdr-safe elt)))
 463                    (or (keymapp (cdr-safe (cdr-safe elt)))
 464                        (eq (car (cdr-safe (cdr-safe elt))) 'lambda))
 465                  (and (symbolp (cdr-safe (cdr-safe elt)))
 466                       (fboundp (cdr-safe (cdr-safe elt)))))
 467                (setq km (cddr elt))
 468                (and (stringp (car elt)) (setq str (car elt))))
 469
 470               ((eq (car-safe elt) 'menu-item)
 471                ;; (menu-item TITLE COMMAND KEY ...)
 472                (setq plist (cdr-safe (cdr-safe (cdr-safe elt))))
 473                (when (consp (car-safe plist))
 474                  (setq plist (cdr-safe plist)))
 475                (setq km (nth 2 elt))
 476                (setq str (eval (nth 1 elt)))
 477                (setq filter (plist-get plist :filter))
 478                (if filter
 479                    (setq km (funcall filter km)))
 480                (setq visible (plist-get plist :visible))
 481                (if visible
 482                    (setq km (and (eval visible) km)))
 483                (setq enable (plist-get plist :enable))
 484                (if enable
 485                    (setq km (if (eval enable) km 'ignore))))
 486
 487               ((if (listp (cdr-safe (cdr-safe (cdr-safe elt))))
 488                    (or (keymapp (cdr-safe (cdr-safe (cdr-safe elt))))
 489                        (eq (car (cdr-safe (cdr-safe (cdr-safe elt)))) 'lambda))
 490                  (and (symbolp (cdr-safe (cdr-safe (cdr-safe elt))))
 491                       (fboundp (cdr-safe (cdr-safe (cdr-safe elt))))))
 492                                         ; New style of easy-menu
 493                (setq km (cdr (cddr elt)))
 494                (and (stringp (car elt)) (setq str (car elt))))
 495
 496               ((stringp event)          ; x-popup or x-popup element
 497                (setq str event)
 498                (setq event nil)
 499                (setq km (if (or in-x-menu (stringp (car-safe elt)))
 500                             elt (cons 'keymap elt)))))
 501         (unless (or (eq km 'ignore) (null str))
 502           (let ((binding (where-is-internal km nil t)))
 503             (when binding
 504               (setq binding (key-description binding))
 505               ;; Try to align the keybindings.
 506               (let ((colwidth (min 30 (- (/ (window-width) 2) 10))))
 507                 (setq str
 508                       (concat str
 509                               (make-string (max 2 (- colwidth
 510                                                      (string-width str)
 511                                                      (string-width binding)))
 512                                            ?\s)
 513                               binding)))))))
 514       (and km (stringp km) (setq str km))
 515       ;; Verify that the command is enabled;
 516       ;; if not, don't mention it.
 517       (when (and km (symbolp km) (get km 'menu-enable))
 518           (setq km (if (eval (get km 'menu-enable)) km 'ignore)))
 519       (and km str
 520            (or (assoc str tmm-km-list)
 521                (push (cons str (cons event km)) tmm-km-list))))))
 522
 523 (defun tmm-get-keybind (keyseq)
 524   "Return the current binding of KEYSEQ, merging prefix definitions.
 525 If KEYSEQ is a prefix key that has local and global bindings,
 526 we merge them into a single keymap which shows the proper order of the menu.
 527 However, for the menu bar itself, the value does not take account
 528 of `menu-bar-final-items'."
 529   (lookup-key (cons 'keymap (nreverse (current-active-maps))) keyseq))
 530
 531 (provide 'tmm)
 532
 533 ;;; tmm.el ends here