[gnu-emacs] / lisp / emulation / viper-macs.el

;;; viper-macs.el --- functions implementing keyboard macros for Viper

;; Copyright (C) 1994-1997, 2000-2013 Free Software Foundation, Inc.

;; Author: Michael Kifer <kifer@cs.stonybrook.edu>
;; Package: viper

;; This file is part of GNU Emacs.

;; GNU Emacs 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 Emacs 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 Emacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;;; Code:

(provide 'viper-macs)

;; compiler pacifier
(defvar viper-ex-work-buf)
(defvar viper-custom-file-name)
(defvar viper-current-state)
(defvar viper-fast-keyseq-timeout)
(require 'viper-mous)
(require 'viper-ex)
;; end pacifier

(require 'viper-util)
(require 'viper-keym)


;;; Variables

;; Register holding last macro.
(defvar viper-last-macro-reg nil)

;; format of the elements of kbd alists:
;; (name ((buf . macr)...(buf . macr)) ((maj-mode . macr)...) (t . macr))
;; kbd macro alist for Vi state
(defvar viper-vi-kbd-macro-alist nil)
;; same for insert/replace state
(defvar viper-insert-kbd-macro-alist nil)
;; same for emacs state
(defvar viper-emacs-kbd-macro-alist nil)

;; Internal var that passes info between start-kbd-macro and end-kbd-macro
;; in :map and :map!
(defvar viper-kbd-macro-parameters nil)

(defvar viper-this-kbd-macro nil
  "Vector of keys representing the name of currently running Viper kbd macro.")
(defvar viper-last-kbd-macro nil
  "Vector of keys representing the name of last Viper keyboard macro.")

(defcustom viper-repeat-from-history-key 'f12
  "Prefix key for accessing previously typed Vi commands.

The previous command is accessible, as usual, via `.'.  The command before this
can be invoked as `<this key> 1', and the command before that, and the command
before that one is accessible as `<this key> 2'.
The notation for these keys is borrowed from XEmacs.  Basically,
a key is a symbol, e.g., `a', `\\1', `f2', etc., or a list, e.g.,
`(meta control f1)'."
  :type 'sexp
  :group 'viper)


\f
;;; Code

(declare-function viper-change-state-to-insert "viper-cmd" ())

;; Ex map command
(defun ex-map ()
  (let ((mod-char "")
        macro-name macro-body map-args ins)
    (save-window-excursion
      (set-buffer viper-ex-work-buf)
      (if (looking-at "!")
          (progn
            (setq ins t
                  mod-char "!")
            (forward-char 1))))
    (setq map-args (ex-map-read-args mod-char)
          macro-name (car map-args)
          macro-body (cdr map-args))
    (setq viper-kbd-macro-parameters (list ins mod-char macro-name macro-body))
    (if macro-body
        (viper-end-mapping-kbd-macro 'ignore)
      (ex-fixup-history (format "map%s %S" mod-char
                                (viper-display-macro macro-name)))
      ;; if defining macro for insert, switch there for authentic WYSIWYG
      (if ins (viper-change-state-to-insert))
      (start-kbd-macro nil)
      (define-key viper-vi-intercept-map "\C-x)" 'viper-end-mapping-kbd-macro)
      (define-key viper-insert-intercept-map "\C-x)" 'viper-end-mapping-kbd-macro)
      (define-key viper-emacs-intercept-map "\C-x)" 'viper-end-mapping-kbd-macro)
      (message "Mapping %S in %s state.  Type macro definition followed by `C-x )'"
               (viper-display-macro macro-name)
               (if ins "Insert" "Vi")))
    ))


;; Ex unmap
(defun ex-unmap ()
  (let ((mod-char "")
        temp macro-name ins)
    (save-window-excursion
      (set-buffer viper-ex-work-buf)
      (if (looking-at "!")
          (progn
            (setq ins t
                  mod-char "!")
            (forward-char 1))))

    (setq macro-name (ex-unmap-read-args mod-char))
    (setq temp (viper-fixup-macro (vconcat macro-name))) ;; copy and fixup
    (ex-fixup-history (format "unmap%s %S" mod-char
                              (viper-display-macro temp)))
    (viper-unrecord-kbd-macro macro-name (if ins 'insert-state 'vi-state))
    ))


;; read arguments for ex-map
(defun ex-map-read-args (variant)
  (let ((cursor-in-echo-area t)
        (key-seq [])
        temp key event message
        macro-name macro-body args)

    (condition-case nil
        (setq args (concat (ex-get-inline-cmd-args ".*map[!]*[ \t]?" "\n\C-m")
                           " nil nil ")
              temp (read-from-string args)
              macro-name (car temp)
              macro-body (car (read-from-string args (cdr temp))))
      (error
       (signal
        'error
        '("map: Macro name and body must be a quoted string or a vector"))))

    ;; We expect macro-name to be a vector, a string, or a quoted string.
    ;; In the second case, it will emerge as a symbol when read from
    ;; the above read-from-string.  So we need to convert it into a string
    (if macro-name
        (cond ((vectorp macro-name) nil)
              ((stringp macro-name)
               (setq macro-name (vconcat macro-name)))
              (t (setq macro-name (vconcat (prin1-to-string macro-name)))))
      (message ":map%s <Macro Name>" variant)(sit-for 2)
      (while
          (not (member key
                       '(?\C-m ?\n (control m) (control j) return linefeed)))
        (setq key-seq (vconcat key-seq (if key (vector key) [])))
        ;; the only keys available for editing are these-- no help while there
        (if (member
             key
             '(?\b ?\d '^? '^H (control h) (control \?) backspace delete))
            (setq key-seq (viper-subseq key-seq 0 (- (length key-seq) 2))))
        (setq message
              (format
               ":map%s %s"
               variant (if (> (length key-seq) 0)
                           (prin1-to-string (viper-display-macro key-seq))
                         "")))
        (message "%s" message)
        (setq event (viper-read-key))
        ;;(setq event (viper-read-event))
        (setq key
              (if (viper-mouse-event-p event)
                  (progn
                    (message "%s (No mouse---only keyboard keys, please)"
                             message)
                    (sit-for 2)
                    nil)
                (viper-event-key event)))
        )
      (setq macro-name key-seq))

    (if (= (length macro-name) 0)
        (error "Can't map an empty macro name"))
    (setq macro-name (viper-fixup-macro macro-name))
    (if (viper-char-array-p macro-name)
        (setq macro-name (viper-char-array-to-macro macro-name)))

    (if macro-body
        (cond ((viper-char-array-p macro-body)
               (setq macro-body (viper-char-array-to-macro macro-body)))
              ((vectorp macro-body) nil)
              (t (error "map: Invalid syntax in macro definition"))))
    (setq cursor-in-echo-area nil)(sit-for 0) ; this overcomes xemacs tty bug
    (cons macro-name macro-body)))



;; read arguments for ex-unmap
(defun ex-unmap-read-args (variant)
  (let ((cursor-in-echo-area t)
        (macro-alist (if (string= variant "!")
                         viper-insert-kbd-macro-alist
                       viper-vi-kbd-macro-alist))
        ;; these are disabled just in case, to avoid surprises when doing
        ;; completing-read
        viper-vi-kbd-minor-mode viper-insert-kbd-minor-mode
        viper-emacs-kbd-minor-mode
        viper-vi-intercept-minor-mode viper-insert-intercept-minor-mode
        viper-emacs-intercept-minor-mode
        event message
        key key-seq macro-name)
    (setq macro-name (ex-get-inline-cmd-args ".*unma?p?[!]*[ \t]*"))

    (if (> (length macro-name) 0)
        ()
      (message ":unmap%s <Name>" variant) (sit-for 2)
      (while
          (not
           (member key '(?\C-m ?\n (control m) (control j) return linefeed)))
        (setq key-seq (vconcat key-seq (if key (vector key) [])))
        ;; the only keys available for editing are these-- no help while there
        (cond ((member
                key
                '(?\b ?\d '^? '^H (control h) (control \?) backspace delete))
               (setq key-seq (viper-subseq key-seq 0 (- (length key-seq) 2))))
              ((member key '(tab (control i) ?\t))
               (setq key-seq (viper-subseq key-seq 0 (1- (length key-seq))))
               (setq message
                     (format
                      ":unmap%s %s"
                      variant (if (> (length key-seq) 0)
                                  (prin1-to-string
                                   (viper-display-macro key-seq))
                                "")))
               (setq key-seq
                     (viper-do-sequence-completion key-seq macro-alist message))
               ))
        (setq message
              (format
               ":unmap%s %s"
               variant (if (> (length key-seq) 0)
                           (prin1-to-string
                            (viper-display-macro key-seq))
                         "")))
        (message "%s" message)
        (setq event (viper-read-key))
        ;;(setq event (viper-read-event))
        (setq key
              (if (viper-mouse-event-p event)
                  (progn
                    (message "%s (No mouse---only keyboard keys, please)"
                             message)
                    (sit-for 2)
                    nil)
                (viper-event-key event)))
        )
      (setq macro-name key-seq))

    (if (= (length macro-name) 0)
        (error "Can't unmap an empty macro name"))

    ;; convert macro names into vector, if starts with a `['
    (if (memq (elt macro-name 0) '(?\[ ?\"))
        (car (read-from-string macro-name))
      (vconcat macro-name))
    ))


(declare-function viper-change-state-to-vi "viper-cmd" ())

;; Terminate a Vi kbd macro.
;; optional argument IGNORE, if t, indicates that we are dealing with an
;; existing macro that needs to be registered, but there is no need to
;; terminate a kbd macro.
(defun viper-end-mapping-kbd-macro (&optional ignore)
  (interactive)
  (define-key viper-vi-intercept-map "\C-x)" nil)
  (define-key viper-insert-intercept-map "\C-x)" nil)
  (define-key viper-emacs-intercept-map "\C-x)" nil)
  (if (and (not ignore)
           (or (not viper-kbd-macro-parameters)
               (not defining-kbd-macro)))
      (error "Not mapping a kbd-macro"))
  (let ((mod-char (nth 1 viper-kbd-macro-parameters))
        (ins (nth 0 viper-kbd-macro-parameters))
        (macro-name (nth 2 viper-kbd-macro-parameters))
        (macro-body (nth 3 viper-kbd-macro-parameters)))
    (setq viper-kbd-macro-parameters nil)
    (or ignore
        (progn
          (end-kbd-macro nil)
          (setq macro-body (viper-events-to-macro last-kbd-macro))
          ;; always go back to Vi, since this is where we started
          ;; defining macro
          (viper-change-state-to-vi)))

    (viper-record-kbd-macro macro-name
                          (if ins 'insert-state 'vi-state)
                          (viper-display-macro macro-body))

    (ex-fixup-history (format "map%s %S %S" mod-char
                              (viper-display-macro macro-name)
                              (viper-display-macro macro-body)))
    ))



\f
;;; Recording, unrecording, executing

;; Accepts as macro names: strings and vectors.
;; strings must be strings of characters; vectors must be vectors of keys
;; in canonical form, which is essentially the form used in XEmacs.
;; More general definitions are inherited by more specific scopes:
;; global->major mode->buffer. More specific definitions override more general
(defun viper-record-kbd-macro (macro-name state macro-body &optional scope)
  "Record a Vi macro.  Can be used in `.viper' file to define permanent macros.
MACRO-NAME is a string of characters or a vector of keys.  STATE is
either `vi-state' or `insert-state'.  It specifies the Viper state in which to
define the macro.  MACRO-BODY is a string that represents the keyboard macro.
Optional SCOPE says whether the macro should be global \(t\), mode-specific
\(a major-mode symbol\), or buffer-specific \(buffer name, a string\).
If SCOPE is nil, the user is asked to specify the scope."
  (let* (state-name keymap
         (macro-alist-var
          (cond ((eq state 'vi-state)
                 (setq state-name "Vi state"
                       keymap viper-vi-kbd-map)
                 'viper-vi-kbd-macro-alist)
                ((memq state '(insert-state replace-state))
                 (setq state-name "Insert state"
                       keymap viper-insert-kbd-map)
                 'viper-insert-kbd-macro-alist)
                (t
                 (setq state-name "Emacs state"
                       keymap viper-emacs-kbd-map)
                 'viper-emacs-kbd-macro-alist)
                 ))
         new-elt old-elt old-sub-elt msg
         temp lis lis2)

    (if (= (length macro-name) 0)
        (error "Can't map an empty macro name"))

    ;; Macro-name is usually a vector.  However, command history or macros
    ;; recorded in ~/.viper may be recorded as strings.  So, convert to
    ;; vectors.
    (setq macro-name (viper-fixup-macro macro-name))
    (if (viper-char-array-p macro-name)
        (setq macro-name (viper-char-array-to-macro macro-name)))
    (setq macro-body (viper-fixup-macro macro-body))
    (if (viper-char-array-p macro-body)
        (setq macro-body (viper-char-array-to-macro macro-body)))

    ;; don't ask if scope is given and is of the right type
    (or (eq scope t)
        (stringp scope)
        (and scope (symbolp scope))
        (progn
          (setq scope
                (cond
                 ((y-or-n-p
                   (format
                    "Map this macro for buffer `%s' only? "
                    (buffer-name)))
                  (setq msg
                        (format
                         "%S is mapped to %s for %s in `%s'"
                         (viper-display-macro macro-name)
                         (viper-abbreviate-string
                          (format
                           "%S"
                           (setq temp (viper-display-macro macro-body)))
                          14 "" ""
                          (if (stringp temp) "  ....\"" "  ....]"))
                         state-name (buffer-name)))
                  (buffer-name))
                 ((y-or-n-p
                   (format
                    "Map this macro for the major mode `%S' only? "
                    major-mode))
                  (setq msg
                        (format
                         "%S is mapped to %s for %s in `%S'"
                         (viper-display-macro macro-name)
                         (viper-abbreviate-string
                          (format
                           "%S"
                           (setq temp (viper-display-macro macro-body)))
                          14 "" ""
                          (if (stringp macro-body) "  ....\"" "  ....]"))
                         state-name major-mode))
                  major-mode)
                 (t
                  (setq msg
                        (format
                         "%S is globally mapped to %s in %s"
                         (viper-display-macro macro-name)
                         (viper-abbreviate-string
                          (format
                           "%S"
                           (setq temp (viper-display-macro macro-body)))
                          14 "" ""
                          (if (stringp macro-body) "  ....\"" "  ....]"))
                         state-name))
                  t)))
          (if (y-or-n-p
               (format "Save this macro in %s? "
                       (viper-abbreviate-file-name viper-custom-file-name)))
              (viper-save-string-in-file
               (format "\n(viper-record-kbd-macro %S '%S %s '%S)"
                       (viper-display-macro macro-name)
                       state
                       ;; if we don't let vector macro-body through %S,
                       ;; the symbols `\.' `\[' etc will be converted into
                       ;; characters, causing invalid read  error on recorded
                       ;; macros in .viper.
                       ;; I am not sure is macro-body can still be a string at
                       ;; this point, but I am preserving this option anyway.
                       (if (vectorp macro-body)
                           (format "%S" macro-body)
                         macro-body)
                       scope)
               viper-custom-file-name))

          (message "%s" msg)
          ))

    (setq new-elt
          (cons macro-name
                (cond ((eq scope t) (list nil nil (cons t nil)))
                      ((symbolp scope)
                       (list nil (list (cons scope nil)) (cons t nil)))
                      ((stringp scope)
                       (list (list (cons scope nil)) nil (cons t nil))))))
    (setq old-elt (assoc macro-name (eval macro-alist-var)))

    (if (null old-elt)
        (progn
          ;; insert new-elt in macro-alist-var and keep the list sorted
          (define-key
            keymap
            (vector (viper-key-to-emacs-key (aref macro-name 0)))
            'viper-exec-mapped-kbd-macro)
          (setq lis (eval macro-alist-var))
          (while (and lis (string< (viper-array-to-string (car (car lis)))
                                   (viper-array-to-string macro-name)))
            (setq lis2 (cons (car lis) lis2))
            (setq lis (cdr lis)))

          (setq lis2 (reverse lis2))
          (set macro-alist-var (append lis2 (cons new-elt lis)))
          (setq old-elt new-elt)))
    (setq old-sub-elt
          (cond ((eq scope t) (viper-kbd-global-pair old-elt))
                ((symbolp scope) (assoc scope (viper-kbd-mode-alist old-elt)))
                ((stringp scope) (assoc scope (viper-kbd-buf-alist old-elt)))))
    (if old-sub-elt
        (setcdr old-sub-elt macro-body)
      (cond ((symbolp scope) (setcar (cdr (cdr old-elt))
                                     (cons (cons scope macro-body)
                                           (viper-kbd-mode-alist old-elt))))
            ((stringp scope) (setcar (cdr old-elt)
                                     (cons (cons scope macro-body)
                                           (viper-kbd-buf-alist old-elt))))))
    ))



;; macro name must be a vector of viper-style keys
;; viper-unrecord-kbd-macro doesn't have scope. Macro definitions are inherited
;; from global -> major mode -> buffer
;; More specific definition overrides more general
;; Can't unrecord definition for more specific, if a more general definition is
;; in effect
(defun viper-unrecord-kbd-macro (macro-name state)
  "Delete macro MACRO-NAME from Viper STATE.
MACRO-NAME must be a vector of viper-style keys.  This command is used by Viper
internally, but the user can also use it in ~/.viper to delete pre-defined
macros supplied with Viper.  The best way to avoid mistakes in macro names to
be passed to this function is to use viper-describe-kbd-macros and copy the
name from there."
  (let* (state-name keymap
         (macro-alist-var
          (cond ((eq state 'vi-state)
                 (setq state-name "Vi state"
                       keymap viper-vi-kbd-map)
                 'viper-vi-kbd-macro-alist)
                ((memq state '(insert-state replace-state))
                 (setq state-name "Insert state"
                       keymap viper-insert-kbd-map)
                 'viper-insert-kbd-macro-alist)
                (t
                 (setq state-name "Emacs state"
                       keymap viper-emacs-kbd-map)
                 'viper-emacs-kbd-macro-alist)
                ))
         buf-mapping mode-mapping global-mapping
         macro-pair macro-entry)

    ;; Macro-name is usually a vector.  However, command history or macros
    ;; recorded in ~/.viper may appear as strings.  So, convert to vectors.
    (setq macro-name (viper-fixup-macro macro-name))
    (if (viper-char-array-p macro-name)
        (setq macro-name (viper-char-array-to-macro macro-name)))

    (setq macro-entry (assoc macro-name (eval macro-alist-var)))
    (if (= (length macro-name) 0)
        (error "Can't unmap an empty macro name"))
    (if (null macro-entry)
        (error "%S is not mapped to a macro for %s in `%s'"
               (viper-display-macro macro-name)
               state-name (buffer-name)))

    (setq buf-mapping (viper-kbd-buf-pair macro-entry)
          mode-mapping (viper-kbd-mode-pair macro-entry)
          global-mapping (viper-kbd-global-pair macro-entry))

    (cond ((and (cdr buf-mapping)
                (or (and (not (cdr mode-mapping)) (not (cdr global-mapping)))
                    (y-or-n-p
                     (format "Unmap %S for `%s' only? "
                             (viper-display-macro macro-name)
                             (buffer-name)))))
           (setq macro-pair buf-mapping)
           (message "%S is unmapped for %s in `%s'"
                    (viper-display-macro macro-name)
                    state-name (buffer-name)))
          ((and (cdr mode-mapping)
                (or (not (cdr global-mapping))
                    (y-or-n-p
                     (format "Unmap %S for the major mode `%S' only? "
                             (viper-display-macro macro-name)
                             major-mode))))
           (setq macro-pair mode-mapping)
           (message "%S is unmapped for %s in %S"
                    (viper-display-macro macro-name) state-name major-mode))
          ((cdr (setq macro-pair global-mapping))
           (message
            "Global mapping for %S in %s is removed"
            (viper-display-macro macro-name) state-name))
          (t (error "%S is not mapped to a macro for %s in `%s'"
                    (viper-display-macro macro-name)
                    state-name (buffer-name))))
    (setcdr macro-pair nil)
    (or (cdr buf-mapping)
        (cdr mode-mapping)
        (cdr global-mapping)
        (progn
          (set macro-alist-var (delq macro-entry (eval macro-alist-var)))
          (if (viper-can-release-key (aref macro-name 0)
                                     (eval macro-alist-var))
              (define-key
                keymap
                (vector (viper-key-to-emacs-key (aref macro-name 0)))
                nil))
          ))
    ))

;; Check if MACRO-ALIST has an entry for a macro name starting with
;; CHAR.  If not, this indicates that the binding for this char
;; in viper-vi/insert-kbd-map can be released.
(defun viper-can-release-key (char macro-alist)
  (let ((lis macro-alist)
        (can-release t)
        macro-name)

    (while (and lis can-release)
      (setq macro-name (car (car lis)))
      (if (eq char (aref macro-name 0))
          (setq can-release nil))
      (setq lis (cdr lis)))
    can-release))


(defun viper-exec-mapped-kbd-macro (count)
  "Dispatch kbd macro."
  (interactive "P")
  (let* ((macro-alist (cond ((eq viper-current-state 'vi-state)
                             viper-vi-kbd-macro-alist)
                            ((memq viper-current-state
                                   '(insert-state replace-state))
                             viper-insert-kbd-macro-alist)
                            (t
                             viper-emacs-kbd-macro-alist)))
        (unmatched-suffix "")
        ;; Macros and keys are executed with other macros turned off
        ;; For macros, this is done to avoid macro recursion
        viper-vi-kbd-minor-mode viper-insert-kbd-minor-mode
        viper-emacs-kbd-minor-mode
        next-best-match keyseq event-seq
        macro-first-char macro-alist-elt macro-body
        command)

    (setq macro-first-char last-command-event
          event-seq (viper-read-fast-keysequence macro-first-char macro-alist)
          keyseq (viper-events-to-macro event-seq)
          macro-alist-elt (assoc keyseq macro-alist)
          next-best-match (viper-find-best-matching-macro macro-alist keyseq))

    (if (null macro-alist-elt)
        (setq macro-alist-elt (car next-best-match)
              unmatched-suffix (viper-subseq event-seq (cdr next-best-match))))

    (cond ((null macro-alist-elt))
          ((setq macro-body (viper-kbd-buf-definition macro-alist-elt)))
          ((setq macro-body (viper-kbd-mode-definition macro-alist-elt)))
          ((setq macro-body (viper-kbd-global-definition macro-alist-elt))))

    ;; when defining keyboard macro, don't use the macro mappings
    (if (and macro-body (not defining-kbd-macro))
        ;; block cmd executed as part of a macro from entering command history
        (let ((command-history command-history))
          (setq viper-this-kbd-macro (car macro-alist-elt))
          (execute-kbd-macro (viper-macro-to-events macro-body) count)
          (setq viper-this-kbd-macro nil
                viper-last-kbd-macro (car macro-alist-elt))
          (viper-set-unread-command-events unmatched-suffix))
      ;; If not a macro, or the macro is suppressed while defining another
      ;; macro, put keyseq back on the event queue
      (viper-set-unread-command-events event-seq)
      ;; if the user typed arg, then use it if prefix arg is not set by
      ;; some other command (setting prefix arg can happen if we do, say,
      ;; 2dw and there is a macro starting with 2.  Then control will go to
      ;; this routine
      (or prefix-arg (setq  prefix-arg count))
      (setq command (key-binding (read-key-sequence nil)))
      (if (commandp command)
          (command-execute command)
        (beep 1)))
    ))


\f
;;; Displaying and completing macros

(defun viper-describe-kbd-macros ()
  "Show currently defined keyboard macros."
  (interactive)
  (with-output-to-temp-buffer " *viper-info*"
    (princ "Macros in Vi state:\n===================\n")
    (mapc 'viper-describe-one-macro viper-vi-kbd-macro-alist)
    (princ "\n\nMacros in Insert and Replace states:\n====================================\n")
    (mapc 'viper-describe-one-macro viper-insert-kbd-macro-alist)
    (princ "\n\nMacros in Emacs state:\n======================\n")
    (mapcar 'viper-describe-one-macro viper-emacs-kbd-macro-alist)
    ))

(defun viper-describe-one-macro (macro)
  (princ (format "\n  *** Mappings for %S:\n      ------------\n"
                 (viper-display-macro (car macro))))
  (princ "   ** Buffer-specific:")
  (if (viper-kbd-buf-alist macro)
      (mapc 'viper-describe-one-macro-elt (viper-kbd-buf-alist macro))
    (princ "  none\n"))
  (princ "\n   ** Mode-specific:")
  (if (viper-kbd-mode-alist macro)
      (mapc 'viper-describe-one-macro-elt (viper-kbd-mode-alist macro))
    (princ "  none\n"))
  (princ "\n   ** Global:")
  (if (viper-kbd-global-definition macro)
      (princ (format "\n           %S" (cdr (viper-kbd-global-pair macro))))
    (princ "  none"))
  (princ "\n"))

(defun viper-describe-one-macro-elt (elt)
  (let ((name (car elt))
        (defn (cdr elt)))
    (princ (format "\n       * %S:\n           %S\n" name defn))))



;; check if SEQ is a prefix of some car of an element in ALIST
(defun viper-keyseq-is-a-possible-macro (seq alist)
  (let ((converted-seq (viper-events-to-macro seq)))
    (eval (cons 'or
                (mapcar
                 (lambda (elt) (viper-prefix-subseq-p converted-seq elt))
                 (viper-this-buffer-macros alist))))))

;; whether SEQ1 is a prefix of SEQ2
(defun viper-prefix-subseq-p (seq1 seq2)
  (let ((len1 (length seq1))
        (len2 (length seq2)))
    (if (<= len1 len2)
        (equal seq1 (viper-subseq seq2 0 len1)))))

;; find the longest common prefix
(defun viper-common-seq-prefix (&rest seqs)
  (let* ((first (car seqs))
         (rest (cdr seqs))
         (pref [])
         (idx 0)
         len)
    (if (= (length seqs) 0)
        (setq len 0)
      (setq len (apply 'min (mapcar 'length seqs))))
    (while (< idx len)
      (if (eval (cons 'and
                      (mapcar (lambda (s) (equal (elt first idx) (elt s idx)))
                              rest)))
          (setq pref (vconcat pref (vector (elt first idx)))))
      (setq idx (1+ idx)))
    pref))

;; get all sequences that match PREFIX from a given A-LIST
(defun viper-extract-matching-alist-members (pref alist)
  (delq nil (mapcar (lambda (elt) (if (viper-prefix-subseq-p pref elt) elt))
                    (viper-this-buffer-macros alist))))

(defun viper-do-sequence-completion (seq alist compl-message)
  (let* ((matches (viper-extract-matching-alist-members seq alist))
         (new-seq (apply 'viper-common-seq-prefix matches))
         )
    (cond ((and (equal seq new-seq) (= (length matches) 1))
           (message "%s (Sole completion)" compl-message)
           (sit-for 2))
          ((null matches)
           (message "%s (No match)" compl-message)
           (sit-for 2)
           (setq new-seq seq))
          ((member seq matches)
           (message "%s (Complete, but not unique)" compl-message)
           (sit-for 2)
           (viper-display-vector-completions matches))
          ((equal seq new-seq)
           (viper-display-vector-completions matches)))
    new-seq))


(defun viper-display-vector-completions (list)
  (with-output-to-temp-buffer "*Completions*"
    (display-completion-list
     (mapcar 'prin1-to-string
             (mapcar 'viper-display-macro list)))))



;; alist is the alist of macros
;; str is the fast key sequence entered
;; returns: (matching-macro-def . unmatched-suffix-start-index)
(defun viper-find-best-matching-macro (alist str)
  (let ((lis alist)
        (def-len 0)
        (str-len (length str))
        match unmatched-start-idx found macro-def)
    (while (and (not found) lis)
      (setq macro-def (car lis)
            def-len (length (car macro-def)))
      (if (and (>= str-len def-len)
               (equal (car macro-def) (viper-subseq str 0 def-len)))
          (if (or (viper-kbd-buf-definition macro-def)
                  (viper-kbd-mode-definition macro-def)
                  (viper-kbd-global-definition macro-def))
              (setq found t))
        )
      (setq lis (cdr lis)))

    (if found
        (setq match macro-def
              unmatched-start-idx def-len)
      (setq match nil
            unmatched-start-idx 0))

    (cons match unmatched-start-idx)))



;; returns a list of names of macros defined for the current buffer
(defun viper-this-buffer-macros (macro-alist)
  (let (candidates)
    (setq candidates
          (mapcar (lambda (elt)
                    (if (or (viper-kbd-buf-definition elt)
                            (viper-kbd-mode-definition elt)
                            (viper-kbd-global-definition elt))
                        (car elt)))
                  macro-alist))
    (setq candidates (delq nil candidates))))


;; if seq of Viper key symbols (representing a macro) can be converted to a
;; string--do so.  Otherwise, do nothing.
(defun viper-display-macro (macro-name-or-body)
  (cond ((viper-char-symbol-sequence-p macro-name-or-body)
         (mapconcat 'symbol-name macro-name-or-body ""))
        ((viper-char-array-p macro-name-or-body)
         (mapconcat 'char-to-string macro-name-or-body ""))
        (t macro-name-or-body)))

;; convert sequence of events (that came presumably from emacs kbd macro) into
;; Viper's macro, which is a vector of the form
;; [ desc desc ... ]
;; Each desc is either a symbol of (meta symb), (shift symb), etc.
;; Here we purge events that happen to be lists.  In most cases, these events
;; got into a macro definition unintentionally; say, when the user moves mouse
;; during a macro definition, then something like (switch-frame ...) might get
;; in.  Another reason for purging lists-events is that we can't store them in
;; textual form (say, in .emacs) and then read them back.
(defun viper-events-to-macro (event-seq)
  (vconcat (delq nil (mapcar (lambda (elt) (if (consp elt)
                                               nil
                                             (viper-event-key elt)))
                             event-seq))))

;; convert strings or arrays of characters to Viper macro form
(defun viper-char-array-to-macro (array)
  (let ((vec (vconcat array))
        macro)
    (if (featurep 'xemacs)
        (setq macro (mapcar 'character-to-event vec))
      (setq macro vec))
    (vconcat (mapcar 'viper-event-key macro))))

;; For macros bodies and names, goes over MACRO and checks if all members are
;; names of keys (actually, it only checks if they are symbols or lists
;; if a digit is found, it is converted into a symbol (e.g., 0 -> \0, etc).
;; If MACRO is not a list or vector -- doesn't change MACRO.
(defun viper-fixup-macro (macro)
  (let ((len (length macro))
        (idx 0)
        elt break)
    (if (or (vectorp macro) (listp macro))
        (while (and (< idx len) (not break))
          (setq elt (elt macro idx))
          (cond ((numberp elt)
                 ;; fix number
                 (if (and (<= 0 elt) (<= elt 9))
                     (cond ((arrayp macro)
                            (aset macro
                                  idx
                                  (intern (char-to-string (+ ?0 elt)))))
                           ((listp macro)
                            (setcar (nthcdr idx macro)
                                    (intern (char-to-string (+ ?0 elt)))))
                           )))
                ((listp elt)
                 (viper-fixup-macro elt))
                ((symbolp elt) nil)
                (t (setq break t)))
          (setq idx (1+ idx))))

      (if break
          (error "Wrong type macro component, symbol-or-listp, %S" elt)
        macro)))

(defun viper-macro-to-events (macro-body)
  (vconcat (mapcar 'viper-key-to-emacs-key macro-body)))


\f
;;; Reading fast key sequences

;; Assuming that CHAR was the first character in a fast succession of key
;; strokes, read the rest.  Return the vector of keys that was entered in
;; this fast succession of key strokes.
;; A fast keysequence is one that is terminated by a pause longer than
;; viper-fast-keyseq-timeout.
(defun viper-read-fast-keysequence (event macro-alist)
  (let ((lis (vector event))
        next-event)
    (while (and (viper-fast-keysequence-p)
           (viper-keyseq-is-a-possible-macro lis macro-alist))
      ;; Seems that viper-read-event is more robust here. We need to be able to
      ;; place these events on unread-command-events list. If we use
      ;; viper-read-key then events will be converted to keys, and sometimes
      ;; (e.g., (control \[)) those keys differ from the corresponding events.
      ;; So, do not use (setq next-event (viper-read-key))
      (setq next-event (viper-read-event))
      (or (viper-mouse-event-p next-event)
          (setq lis (vconcat lis (vector next-event)))))
    lis))

\f
;;; Keyboard macros in registers

;; sets register to last-kbd-macro carefully.
(defun viper-set-register-macro (reg)
  (if (get-register reg)
      (if (y-or-n-p "Register contains data.  Overwrite? ")
          ()
        (error
         "Macro not saved in register.  Can still be invoked via `C-x e'")))
  (set-register reg last-kbd-macro))

(defun viper-register-macro (count)
  "Keyboard macros in registers - a modified \@ command."
  (interactive "P")
  (let ((reg (downcase (read-char))))
    (cond ((or (and (<= ?a reg) (<= reg ?z)))
           (setq viper-last-macro-reg reg)
           (if defining-kbd-macro
               (progn
                 (end-kbd-macro)
                 (viper-set-register-macro reg))
             (execute-kbd-macro (get-register reg) count)))
          ((or (= ?@ reg) (= ?\^j reg) (= ?\^m reg))
           (if viper-last-macro-reg
               nil
               (error "No previous kbd macro"))
           (execute-kbd-macro (get-register viper-last-macro-reg) count))
          ((= ?\# reg)
           (start-kbd-macro count))
          ((= ?! reg)
           (setq reg (downcase (read-char)))
           (if (or (and (<= ?a reg) (<= reg ?z)))
               (progn
               (setq viper-last-macro-reg reg)
               (viper-set-register-macro reg))))
          (t
           (error "`%c': Unknown register" reg)))))


(defun viper-global-execute ()
  "Call last keyboard macro for each line in the region."
  (if (> (point) (mark t)) (exchange-point-and-mark))
  (beginning-of-line)
  (call-last-kbd-macro)
  (while (< (point) (mark t))
    (forward-line 1)
    (beginning-of-line)
    (call-last-kbd-macro)))


;;; viper-macs.el ends here