root/trunk/lisp/emulation/viper-cmd.el

;;; viper-cmd.el --- Vi command support for Viper

;; Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
;;   2005, 2006, 2007, 2008 Free Software Foundation, Inc.

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

;; 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, 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; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;;; Code:

(provide 'viper-cmd)
(require 'advice)

;; Compiler pacifier
(defvar viper-minibuffer-current-face)
(defvar viper-minibuffer-insert-face)
(defvar viper-minibuffer-vi-face)
(defvar viper-minibuffer-emacs-face)
(defvar viper-always)
(defvar viper-mode-string)
(defvar viper-custom-file-name)
(defvar viper--key-maps)
(defvar viper--intercept-key-maps)
(defvar iso-accents-mode)
(defvar quail-mode)
(defvar quail-current-str)
(defvar zmacs-region-stays)
(defvar mark-even-if-inactive)
(defvar init-message)
(defvar initial)
(defvar undo-beg-posn)
(defvar undo-end-posn)

;; loading happens only in non-interactive compilation
;; in order to spare non-viperized emacs from being viperized
(if noninteractive
    (eval-when-compile
      (let ((load-path (cons (expand-file-name ".") load-path)))
        (or (featurep 'viper-util)
            (load "viper-util.el" nil nil 'nosuffix))
        (or (featurep 'viper-keym)
            (load "viper-keym.el" nil nil 'nosuffix))
        (or (featurep 'viper-mous)
            (load "viper-mous.el" nil nil 'nosuffix))
        (or (featurep 'viper-macs)
            (load "viper-macs.el" nil nil 'nosuffix))
        (or (featurep 'viper-ex)
            (load "viper-ex.el" nil nil 'nosuffix))
        )))
;; end pacifier


(require 'viper-util)
(require 'viper-keym)
(require 'viper-mous)
(require 'viper-macs)
(require 'viper-ex)



;; Generic predicates

;; These test functions are shamelessly lifted from vip 4.4.2 by Aamod Sane

;; generate test functions
;; given symbol foo, foo-p is the test function, foos is the set of
;; Viper command keys
;; (macroexpand '(viper-test-com-defun foo))
;; (defun foo-p (com) (consp (memq com foos)))

(defmacro viper-test-com-defun (name)
  (let* ((snm (symbol-name name))
         (nm-p (intern (concat snm "-p")))
         (nms (intern (concat snm "s"))))
    `(defun ,nm-p (com)
       (consp (viper-memq-char com ,nms)
              ))))

;; Variables for defining VI commands

;; Modifying commands that can be prefixes to movement commands
(defvar viper-prefix-commands '(?c ?d ?y ?! ?= ?# ?< ?> ?\"))
;; define viper-prefix-command-p
(viper-test-com-defun viper-prefix-command)

;; Commands that are pairs eg. dd. r and R here are a hack
(defconst viper-charpair-commands '(?c ?d ?y ?! ?= ?< ?> ?r ?R))
;; define viper-charpair-command-p
(viper-test-com-defun viper-charpair-command)

(defconst viper-movement-commands '(?b ?B ?e ?E ?f ?F ?G ?h ?H ?j ?k ?l
                                     ?H ?M ?L ?n ?t ?T ?w ?W ?$ ?%
                                     ?^ ?( ?) ?- ?+ ?| ?{ ?} ?[ ?] ?' ?`
                                     ?\; ?, ?0 ?? ?/ ?\  ?\C-m
                                     space return
                                     delete backspace
                                     )
                                     "Movement commands")
;; define viper-movement-command-p
(viper-test-com-defun viper-movement-command)

;; Vi digit commands
(defconst viper-digit-commands '(?1 ?2 ?3 ?4 ?5 ?6 ?7 ?8 ?9))

;; define viper-digit-command-p
(viper-test-com-defun viper-digit-command)

;; Commands that can be repeated by . (dotted)
(defconst viper-dotable-commands '(?c ?d ?C ?s ?S ?D ?> ?<))
;; define viper-dotable-command-p
(viper-test-com-defun viper-dotable-command)

;; Commands that can follow a #
(defconst viper-hash-commands '(?c ?C ?g ?q ?s))
;; define viper-hash-command-p
(viper-test-com-defun viper-hash-command)

;; Commands that may have registers as prefix
(defconst viper-regsuffix-commands '(?d ?y ?Y ?D ?p ?P ?x ?X))
;; define viper-regsuffix-command-p
(viper-test-com-defun viper-regsuffix-command)

(defconst viper-vi-commands (append viper-movement-commands
                                  viper-digit-commands
                                  viper-dotable-commands
                                  viper-charpair-commands
                                  viper-hash-commands
                                  viper-prefix-commands
                                  viper-regsuffix-commands)
  "The list of all commands in Vi-state.")
;; define viper-vi-command-p
(viper-test-com-defun viper-vi-command)

;; Where viper saves mark. This mark is resurrected by m^
(defvar viper-saved-mark nil)

;; Contains user settings for vars affected by viper-set-expert-level function.
;; Not a user option.
(defvar viper-saved-user-settings nil)



;;; CODE

;; sentinels

;; Runs viper-after-change-functions inside after-change-functions
(defun viper-after-change-sentinel (beg end len)
  (run-hook-with-args 'viper-after-change-functions beg end len))

;; Runs viper-before-change-functions inside before-change-functions
(defun viper-before-change-sentinel (beg end)
  (run-hook-with-args 'viper-before-change-functions beg end))

(defsubst viper-post-command-sentinel ()
  (condition-case conds
      (run-hooks 'viper-post-command-hooks)
    (error (viper-message-conditions conds)))
  (if (eq viper-current-state 'vi-state)
      (viper-restore-cursor-color 'after-insert-mode)))

(defsubst viper-pre-command-sentinel ()
  (run-hooks 'viper-pre-command-hooks))

;; Needed so that Viper will be able to figure the last inserted
;; chunk of text with reasonable accuracy.
(defsubst viper-insert-state-post-command-sentinel ()
  (if (and (memq viper-current-state '(insert-state replace-state))
           viper-insert-point
           (>= (point) viper-insert-point))
      (setq viper-last-posn-while-in-insert-state (point-marker)))
  (or (viper-overlay-p viper-replace-overlay)
      (progn
        (viper-set-replace-overlay (point-min) (point-min))
        (viper-hide-replace-overlay)))
  (if (eq viper-current-state 'insert-state)
      (let ((has-saved-cursor-color-in-insert-mode
             (stringp (viper-get-saved-cursor-color-in-insert-mode))))
        (or has-saved-cursor-color-in-insert-mode
            (string= (viper-get-cursor-color) viper-insert-state-cursor-color)
            ;; save current color, if not already saved
            (viper-save-cursor-color 'before-insert-mode))
        ;; set insert mode cursor color
        (viper-change-cursor-color viper-insert-state-cursor-color)))
  (if (and viper-emacs-state-cursor-color (eq viper-current-state 'emacs-state))
      (let ((has-saved-cursor-color-in-emacs-mode
             (stringp (viper-get-saved-cursor-color-in-emacs-mode))))
        (or has-saved-cursor-color-in-emacs-mode
            (string= (viper-get-cursor-color) viper-emacs-state-cursor-color)
            ;; save current color, if not already saved
            (viper-save-cursor-color 'before-emacs-mode))
        ;; set emacs mode cursor color
        (viper-change-cursor-color viper-emacs-state-cursor-color)))

  (if (and (memq this-command '(dabbrev-expand hippie-expand))
           (integerp viper-pre-command-point)
           (markerp viper-insert-point)
           (marker-position viper-insert-point)
           (> viper-insert-point viper-pre-command-point))
      (viper-move-marker-locally viper-insert-point viper-pre-command-point))
  )

(defsubst viper-preserve-cursor-color ()
  (or (memq this-command '(self-insert-command
                           viper-del-backward-char-in-insert
                           viper-del-backward-char-in-replace
                           viper-delete-backward-char
                           viper-join-lines
                           viper-delete-char))
      (memq (viper-event-key last-command-event)
            '(up down left right (meta f) (meta b)
                 (control n) (control p) (control f) (control b)))))

(defsubst viper-insert-state-pre-command-sentinel ()
  (or (viper-preserve-cursor-color)
      (viper-restore-cursor-color 'after-insert-mode))
  (if (and (memq this-command '(dabbrev-expand hippie-expand))
           (markerp viper-insert-point)
           (marker-position viper-insert-point))
      (setq viper-pre-command-point (marker-position viper-insert-point))))

(defsubst viper-R-state-post-command-sentinel ()
  ;; Restoring cursor color is needed despite
  ;; viper-replace-state-pre-command-sentinel: When you jump to another buffer
  ;; in another frame, the pre-command hook won't change cursor color to
  ;; default in that other frame.  So, if the second frame cursor was red and
  ;; we set the point outside the replacement region, then the cursor color
  ;; will remain red.  Restoring the default, below, prevents this.
  (if (and (<= (viper-replace-start) (point))
           (<=  (point) (viper-replace-end)))
      (viper-change-cursor-color viper-replace-overlay-cursor-color)
    (viper-restore-cursor-color 'after-replace-mode)
    ))

;; to speed up, don't change cursor color before self-insert
;; and common move commands
(defsubst viper-replace-state-pre-command-sentinel ()
  (or (viper-preserve-cursor-color)
      (viper-restore-cursor-color 'after-replace-mode)))


;; Make sure we don't delete more than needed.
;; This is executed at viper-last-posn-in-replace-region
(defsubst viper-trim-replace-chars-to-delete-if-necessary ()
  (setq viper-replace-chars-to-delete
        (max 0
             (min viper-replace-chars-to-delete
                  ;; Don't delete more than to the end of repl overlay
                  (viper-chars-in-region
                   (viper-replace-end) viper-last-posn-in-replace-region)
                  ;; point is viper-last-posn-in-replace-region now
                  ;; So, this limits deletion to the end of line
                  (viper-chars-in-region (point) (viper-line-pos 'end))
                  ))))


(defun viper-replace-state-post-command-sentinel ()
  ;; Restoring cursor color is needed despite
  ;; viper-replace-state-pre-command-sentinel: When one jumps to another buffer
  ;; in another frame, the pre-command hook won't change cursor color to
  ;; default in that other frame.  So, if the second frame cursor was red and
  ;; we set the point outside the replacement region, then the cursor color
  ;; will remain red.  Restoring the default, below, fixes this problem.
  ;;
  ;; We optimize for some commands, like self-insert-command,
  ;; viper-delete-backward-char, etc., since they either don't change
  ;; cursor color or, if they terminate replace mode, the color will be changed
  ;; in viper-finish-change
  (or (viper-preserve-cursor-color)
      (viper-restore-cursor-color 'after-replace-mode))
  (cond
   ((eq viper-current-state 'replace-state)
    ;; delete characters to compensate for inserted chars.
    (let ((replace-boundary (viper-replace-end)))
      (save-excursion
        (goto-char viper-last-posn-in-replace-region)
        (viper-trim-replace-chars-to-delete-if-necessary)
        (delete-char viper-replace-chars-to-delete)
        (setq viper-replace-chars-to-delete 0)
        ;; terminate replace mode if reached replace limit
        (if (= viper-last-posn-in-replace-region (viper-replace-end))
            (viper-finish-change)))

      (if (viper-pos-within-region
           (point) (viper-replace-start) replace-boundary)
          (progn
            ;; the state may have changed in viper-finish-change above
            (if (eq viper-current-state 'replace-state)
                (viper-change-cursor-color viper-replace-overlay-cursor-color))
            (setq viper-last-posn-in-replace-region (point-marker))))
      ))
   ;; terminate replace mode if changed Viper states.
   (t (viper-finish-change))))


;; changing mode

;; Change state to NEW-STATE---either emacs-state, vi-state, or insert-state.
(defun viper-change-state (new-state)
  ;; Keep viper-post/pre-command-hooks fresh.
  ;; We remove then add viper-post/pre-command-sentinel since it is very
  ;; desirable that viper-pre-command-sentinel is the last hook and
  ;; viper-post-command-sentinel is the first hook.

  (viper-cond-compile-for-xemacs-or-emacs
   ;; xemacs
   (progn
     (make-local-hook 'viper-after-change-functions)
     (make-local-hook 'viper-before-change-functions)
     (make-local-hook 'viper-post-command-hooks)
     (make-local-hook 'viper-pre-command-hooks))
   nil ; emacs
   )

  (remove-hook 'post-command-hook 'viper-post-command-sentinel)
  (add-hook 'post-command-hook 'viper-post-command-sentinel)
  (remove-hook 'pre-command-hook 'viper-pre-command-sentinel)
  (add-hook 'pre-command-hook 'viper-pre-command-sentinel t)
  ;; These hooks will be added back if switching to insert/replace mode
  (remove-hook 'viper-post-command-hooks
               'viper-insert-state-post-command-sentinel 'local)
  (remove-hook 'viper-pre-command-hooks
               'viper-insert-state-pre-command-sentinel 'local)
  (setq viper-intermediate-command nil)
  (cond ((eq new-state 'vi-state)
         (cond ((member viper-current-state '(insert-state replace-state))

                ;; move viper-last-posn-while-in-insert-state
                ;; This is a normal hook that is executed in insert/replace
                ;; states after each command.  In Vi/Emacs state, it does
                ;; nothing.  We need to execute it here to make sure that
                ;; the last posn was recorded when we hit ESC.
                ;; It may be left unrecorded if the last thing done in
                ;; insert/repl state was dabbrev-expansion or abbrev
                ;; expansion caused by hitting ESC
                (viper-insert-state-post-command-sentinel)

                (condition-case conds
                    (progn
                      (viper-save-last-insertion
                       viper-insert-point
                       viper-last-posn-while-in-insert-state)
                      (if viper-began-as-replace
                          (setq viper-began-as-replace nil)
                        ;; repeat insert commands if numerical arg > 1
                        (save-excursion
                          (viper-repeat-insert-command))))
                  (error
                   (viper-message-conditions conds)))

                (if (> (length viper-last-insertion) 0)
                    (viper-push-onto-ring viper-last-insertion
                                          'viper-insertion-ring))

                (if viper-ESC-moves-cursor-back
                    (or (bolp) (viper-beginning-of-field) (backward-char 1))))
               ))

        ;; insert or replace
        ((memq new-state '(insert-state replace-state))
         (if (memq viper-current-state '(emacs-state vi-state))
             (viper-move-marker-locally 'viper-insert-point (point)))
         (viper-move-marker-locally
          'viper-last-posn-while-in-insert-state (point))
         (add-hook 'viper-post-command-hooks
                   'viper-insert-state-post-command-sentinel t 'local)
         (add-hook 'viper-pre-command-hooks
                   'viper-insert-state-pre-command-sentinel t 'local))
        ) ; outermost cond

  ;; Nothing needs to be done to switch to emacs mode! Just set some
  ;; variables, which is already done in viper-change-state-to-emacs!

  ;; ISO accents
  ;; always turn off iso-accents-mode in vi-state, or else we won't be able to
  ;; use the keys `,',^ , as they will do accents instead of Vi actions.
  (cond ((eq new-state 'vi-state) (viper-set-iso-accents-mode nil));accents off
        (viper-automatic-iso-accents (viper-set-iso-accents-mode t));accents on
        (t (viper-set-iso-accents-mode nil)))
  ;; Always turn off quail mode in vi state
  (cond ((eq new-state 'vi-state) (viper-set-input-method nil)) ;intl input off
        (viper-special-input-method (viper-set-input-method t)) ;intl input on
        (t (viper-set-input-method nil)))

  (setq viper-current-state new-state)

  (viper-update-syntax-classes)
  (viper-normalize-minor-mode-map-alist)
  (viper-adjust-keys-for new-state)
  (viper-set-mode-vars-for new-state)
  (viper-refresh-mode-line)
  )


(defun viper-adjust-keys-for (state)
  "Make necessary adjustments to keymaps before entering STATE."
  (cond ((memq state '(insert-state replace-state))
         (if viper-auto-indent
             (progn
               (define-key viper-insert-basic-map "\C-m" 'viper-autoindent)
               (if viper-want-emacs-keys-in-insert
                   ;; expert
                   (define-key viper-insert-basic-map "\C-j" nil)
                 ;; novice
                 (define-key viper-insert-basic-map "\C-j" 'viper-autoindent)))
           (define-key viper-insert-basic-map "\C-m" nil)
           (define-key viper-insert-basic-map "\C-j" nil))

         (setq viper-insert-diehard-minor-mode
               (not viper-want-emacs-keys-in-insert))

         (if viper-want-ctl-h-help
             (progn
               (define-key viper-insert-basic-map "\C-h" 'help-command)
               (define-key viper-replace-map "\C-h" 'help-command))
           (define-key viper-insert-basic-map
             "\C-h" 'viper-del-backward-char-in-insert)
           (define-key viper-replace-map
             "\C-h" 'viper-del-backward-char-in-replace))
         ;; In XEmacs, C-h overrides backspace, so we make sure it doesn't.
         (define-key viper-insert-basic-map
           [backspace] 'viper-del-backward-char-in-insert)
         (define-key viper-replace-map
           [backspace] 'viper-del-backward-char-in-replace)
         ) ; end insert/replace case
        (t ; Vi state
         (setq viper-vi-diehard-minor-mode (not viper-want-emacs-keys-in-vi))
         (if viper-want-ctl-h-help
             (define-key viper-vi-basic-map "\C-h" 'help-command)
           (define-key viper-vi-basic-map "\C-h" 'viper-backward-char))
         ;; In XEmacs, C-h overrides backspace, so we make sure it doesn't.
         (define-key viper-vi-basic-map [backspace] 'viper-backward-char))
        ))


;; Normalizes minor-mode-map-alist by putting Viper keymaps first.
;; This ensures that Viper bindings are in effect, regardless of which minor
;; modes were turned on by the user or by other packages.
(defun viper-normalize-minor-mode-map-alist ()
  (setq viper--intercept-key-maps
        (list
         (cons 'viper-vi-intercept-minor-mode viper-vi-intercept-map)
         (cons 'viper-insert-intercept-minor-mode viper-insert-intercept-map)
         (cons 'viper-emacs-intercept-minor-mode viper-emacs-intercept-map)
         ))
  (setq viper--key-maps
        (list (cons 'viper-vi-minibuffer-minor-mode viper-minibuffer-map)
              (cons 'viper-vi-local-user-minor-mode viper-vi-local-user-map)
              (cons 'viper-vi-kbd-minor-mode viper-vi-kbd-map)
              (cons 'viper-vi-global-user-minor-mode viper-vi-global-user-map)
              (cons 'viper-vi-state-modifier-minor-mode
                    (if (keymapp
                         (cdr (assoc major-mode viper-vi-state-modifier-alist)))
                        (cdr (assoc major-mode viper-vi-state-modifier-alist))
                      viper-empty-keymap))
              (cons 'viper-vi-diehard-minor-mode  viper-vi-diehard-map)
              (cons 'viper-vi-basic-minor-mode     viper-vi-basic-map)
               (cons 'viper-replace-minor-mode  viper-replace-map)
               ;; viper-insert-minibuffer-minor-mode must come after
               ;; viper-replace-minor-mode
               (cons 'viper-insert-minibuffer-minor-mode
                     viper-minibuffer-map)
               (cons 'viper-insert-local-user-minor-mode
                     viper-insert-local-user-map)
               (cons 'viper-insert-kbd-minor-mode viper-insert-kbd-map)
               (cons 'viper-insert-global-user-minor-mode
                     viper-insert-global-user-map)
               (cons 'viper-insert-state-modifier-minor-mode
                     (if (keymapp
                          (cdr (assoc major-mode
                                      viper-insert-state-modifier-alist)))
                         (cdr (assoc major-mode
                                     viper-insert-state-modifier-alist))
                       viper-empty-keymap))
               (cons 'viper-insert-diehard-minor-mode viper-insert-diehard-map)
               (cons 'viper-insert-basic-minor-mode viper-insert-basic-map)
               (cons 'viper-emacs-local-user-minor-mode
                     viper-emacs-local-user-map)
               (cons 'viper-emacs-kbd-minor-mode viper-emacs-kbd-map)
               (cons 'viper-emacs-global-user-minor-mode
                     viper-emacs-global-user-map)
               (cons 'viper-emacs-state-modifier-minor-mode
                     (if (keymapp
                          (cdr
                           (assoc major-mode viper-emacs-state-modifier-alist)))
                         (cdr
                          (assoc major-mode viper-emacs-state-modifier-alist))
                       viper-empty-keymap))
               ))
        
  ;; This var is not local in Emacs, so we make it local.  It must be local
  ;; because although the stack of minor modes can be the same for all buffers,
  ;; the associated *keymaps* can be different.  In Viper,
  ;; viper-vi-local-user-map, viper-insert-local-user-map, and others can have
  ;; different keymaps for different buffers.  Also, the keymaps associated
  ;; with viper-vi/insert-state-modifier-minor-mode can be different.
  ;; ***This is needed only in case emulation-mode-map-alists is not defined.
  ;; In emacs with emulation-mode-map-alists, nothing needs to be done
  (unless
      (and (fboundp 'add-to-ordered-list) (boundp 'emulation-mode-map-alists))
    (set (make-local-variable 'minor-mode-map-alist)
         (viper-append-filter-alist
          (append viper--intercept-key-maps viper--key-maps)
          minor-mode-map-alist)))
  )



;; Viper mode-changing commands and utilities

;; Modifies mode-line-buffer-identification.
(defun viper-refresh-mode-line ()
  (set (make-local-variable 'viper-mode-string)
        (cond ((eq viper-current-state 'emacs-state) viper-emacs-state-id)
              ((eq viper-current-state 'vi-state) viper-vi-state-id)
              ((eq viper-current-state 'replace-state) viper-replace-state-id)
              ((eq viper-current-state 'insert-state) viper-insert-state-id)))

  ;; Sets Viper mode string in global-mode-string
  (force-mode-line-update))


;; Switch from Insert state to Vi state.
(defun viper-exit-insert-state ()
  (interactive)
  (viper-change-state-to-vi))

(defun viper-set-mode-vars-for (state)
  "Sets Viper minor mode variables to put Viper's state STATE in effect."

  ;; Emacs state
  (setq viper-vi-minibuffer-minor-mode       nil
        viper-insert-minibuffer-minor-mode   nil
        viper-vi-intercept-minor-mode        nil
        viper-insert-intercept-minor-mode    nil

        viper-vi-local-user-minor-mode       nil
        viper-vi-kbd-minor-mode              nil
        viper-vi-global-user-minor-mode      nil
        viper-vi-state-modifier-minor-mode   nil
        viper-vi-diehard-minor-mode          nil
        viper-vi-basic-minor-mode            nil

        viper-replace-minor-mode               nil

        viper-insert-local-user-minor-mode     nil
        viper-insert-kbd-minor-mode            nil
        viper-insert-global-user-minor-mode    nil
        viper-insert-state-modifier-minor-mode nil
        viper-insert-diehard-minor-mode        nil
        viper-insert-basic-minor-mode          nil
        viper-emacs-intercept-minor-mode       t
        viper-emacs-local-user-minor-mode      t
        viper-emacs-kbd-minor-mode             (not (viper-is-in-minibuffer))
        viper-emacs-global-user-minor-mode     t
        viper-emacs-state-modifier-minor-mode  t
        )

  ;; Vi state
  (if (eq state 'vi-state) ; adjust for vi-state
      (setq
       viper-vi-intercept-minor-mode       t
       viper-vi-minibuffer-minor-mode      (viper-is-in-minibuffer)
       viper-vi-local-user-minor-mode      t
       viper-vi-kbd-minor-mode             (not (viper-is-in-minibuffer))
       viper-vi-global-user-minor-mode     t
       viper-vi-state-modifier-minor-mode    t
       ;; don't let the diehard keymap block command completion
       ;; and other things in the minibuffer
       viper-vi-diehard-minor-mode         (not
                                            (or viper-want-emacs-keys-in-vi
                                                (viper-is-in-minibuffer)))
       viper-vi-basic-minor-mode              t
       viper-emacs-intercept-minor-mode       nil
       viper-emacs-local-user-minor-mode      nil
       viper-emacs-kbd-minor-mode             nil
       viper-emacs-global-user-minor-mode     nil
       viper-emacs-state-modifier-minor-mode  nil
       ))

  ;; Insert and Replace states
  (if (member state '(insert-state replace-state))
      (setq
       viper-insert-intercept-minor-mode      t
       viper-replace-minor-mode               (eq state 'replace-state)
       viper-insert-minibuffer-minor-mode     (viper-is-in-minibuffer)
       viper-insert-local-user-minor-mode     t
       viper-insert-kbd-minor-mode            (not (viper-is-in-minibuffer))
       viper-insert-global-user-minor-mode     t
       viper-insert-state-modifier-minor-mode  t
       ;; don't let the diehard keymap block command completion
       ;; and other things in the minibuffer
       viper-insert-diehard-minor-mode        (not
                                               (or
                                                viper-want-emacs-keys-in-insert
                                                (viper-is-in-minibuffer)))
       viper-insert-basic-minor-mode          t
       viper-emacs-intercept-minor-mode       nil
       viper-emacs-local-user-minor-mode      nil
       viper-emacs-kbd-minor-mode             nil
       viper-emacs-global-user-minor-mode     nil
       viper-emacs-state-modifier-minor-mode  nil
       ))

  ;; minibuffer faces
  (if (viper-has-face-support-p)
      (setq viper-minibuffer-current-face
            (cond ((eq state 'emacs-state) viper-minibuffer-emacs-face)
                  ((eq state 'vi-state) viper-minibuffer-vi-face)
                  ((memq state '(insert-state replace-state))
                   viper-minibuffer-insert-face))))

  (if (viper-is-in-minibuffer)
      (viper-set-minibuffer-overlay))
  )

;; This also takes care of the annoying incomplete lines in files.
;; Also, this fixes `undo' to work vi-style for complex commands.
(defun viper-change-state-to-vi ()
  "Change Viper state to Vi."
  (interactive)
  (if (and viper-first-time (not (viper-is-in-minibuffer)))
      (viper-mode)
    (if overwrite-mode (overwrite-mode -1))
    (or (viper-overlay-p viper-replace-overlay)
      (viper-set-replace-overlay (point-min) (point-min)))
    (viper-hide-replace-overlay)
    (if abbrev-mode (expand-abbrev))
    (if (and auto-fill-function (> (current-column) fill-column))
        (funcall auto-fill-function))
    ;; don't leave whitespace lines around
    (if (and (memq last-command
                   '(viper-autoindent
                     viper-open-line viper-Open-line
                     viper-replace-state-exit-cmd))
             (viper-over-whitespace-line))
        (indent-to-left-margin))
    (viper-add-newline-at-eob-if-necessary)
    (viper-adjust-undo)

    (if (eq viper-current-state 'emacs-state)
        (viper-restore-cursor-color 'after-emacs-mode)
      (viper-restore-cursor-color 'after-insert-mode))

    (viper-change-state 'vi-state)

    ;; Protect against user errors in hooks
    (condition-case conds
        (run-hooks 'viper-vi-state-hook)
      (error
       (viper-message-conditions conds)))))

(defun viper-change-state-to-insert ()
  "Change Viper state to Insert."
  (interactive)
  (viper-change-state 'insert-state)

  (or (viper-overlay-p viper-replace-overlay)
      (viper-set-replace-overlay (point-min) (point-min)))
  (viper-hide-replace-overlay)

  (let ((has-saved-cursor-color-in-insert-mode
         (stringp (viper-get-saved-cursor-color-in-insert-mode))))
    (or has-saved-cursor-color-in-insert-mode
        (string= (viper-get-cursor-color) viper-insert-state-cursor-color)
        (viper-save-cursor-color 'before-insert-mode))
    (viper-change-cursor-color viper-insert-state-cursor-color))

  ;; Protect against user errors in hooks
  (condition-case conds
      (run-hooks 'viper-insert-state-hook)
    (error
     (viper-message-conditions conds))))

(defsubst viper-downgrade-to-insert ()
  ;; Protect against user errors in hooks
  (condition-case conds
      (run-hooks 'viper-insert-state-hook)
    (error
     (viper-message-conditions conds)))
  (setq viper-current-state 'insert-state
        viper-replace-minor-mode nil))



;; Change to replace state.  When the end of replacement region is reached,
;; replace state changes to insert state.
(defun viper-change-state-to-replace (&optional non-R-cmd)
  (viper-change-state 'replace-state)
  ;; Run insert-state-hook
  (condition-case conds
      (run-hooks 'viper-insert-state-hook 'viper-replace-state-hook)
    (error
     (viper-message-conditions conds)))

  (if non-R-cmd
      (viper-start-replace)
    ;; 'R' is implemented using Emacs's overwrite-mode
    (viper-start-R-mode))
  )


(defun viper-change-state-to-emacs ()
  "Change Viper state to Emacs."
  (interactive)
  (or (viper-overlay-p viper-replace-overlay)
      (viper-set-replace-overlay (point-min) (point-min)))
  (viper-hide-replace-overlay)

  (if viper-emacs-state-cursor-color
      (let ((has-saved-cursor-color-in-emacs-mode
             (stringp (viper-get-saved-cursor-color-in-emacs-mode))))
        (or has-saved-cursor-color-in-emacs-mode
            (string= (viper-get-cursor-color) viper-emacs-state-cursor-color)
            (viper-save-cursor-color 'before-emacs-mode))
        (viper-change-cursor-color viper-emacs-state-cursor-color)))

  (viper-change-state 'emacs-state)

  ;; Protect against user errors in hooks
  (condition-case conds
      (run-hooks 'viper-emacs-state-hook)
    (error
     (viper-message-conditions conds))))

;; escape to emacs mode termporarily
(defun viper-escape-to-emacs (arg &optional events)
  "Escape to Emacs state from Vi state for one Emacs command.
ARG is used as the prefix value for the executed command.  If
EVENTS is a list of events, which become the beginning of the command."
  (interactive "P")
  (if (viper= last-command-char ?\\)
      (message "Switched to EMACS state for the next command..."))
  (viper-escape-to-state arg events 'emacs-state))

;; escape to Vi mode termporarily
(defun viper-escape-to-vi (arg)
  "Escape from Emacs state to Vi state for one Vi 1-character command.
If the Vi command that the user types has a prefix argument, e.g., `d2w', then
Vi's prefix argument will be used.  Otherwise, the prefix argument passed to
`viper-escape-to-vi' is used."
  (interactive "P")</