;; proof.el Major mode for proof assistants
;; Copyright (C) 1994 - 1998 LFCS Edinburgh. 
;; Authors: Yves Bertot, Healfdene Goguen, Thomas Kleymann and Dilip Sequeira

;; Maintainer: LEGO Team <lego@dcs.ed.ac.uk>
;; Thanks to David Aspinall, Robert Boyer, Rod Burstall,
;;           James McKinna, Mark Ruys, Martin Steffen, Perdita Stevens  



;; $Log$
;; Revision 1.56  1998/06/10 14:00:21  hhg
;; In proof-init-segmentation, only create proof-queue-span and
;; proof-locked-span if they don't already exist.
;; Call generic span function for making spans read-only.
;;
;; Revision 1.55  1998/06/10 12:39:14  hhg
;; Added proof-unprocessed-begin as general function to find beginning of
;; unprocessed region.  This should be used instead of proof-locked-end
;; if we're not guaranteed to be in scripting buffer.
;; proof-locked-end now calls proof-unprocessed-begin if we're in the
;; proof-script-buffer.
;; We set the goal name to "Unnamed_thm" if we can't find any other name
;; for the theorem.
;; proof-process-active-terminator now calls proof-unprocessed-begin.
;; proof-shell-config-done now calls 'proof-mode-hook.
;;
;; Revision 1.54  1998/06/09 13:14:25  tms
;; o fixed bug in setting proof-queue-face on a colour terminal for GNU
;;   Emacs (19.34)
;; o adjusting the directory (at least for LEGO) must not contain "~". We
;;   now expand `default-directory' before cding to it. [Under XEmacs
;;   (unlike Emacs 19.34), `default-directory' is already in expanded form.]
;;
;; Revision 1.53  1998/06/03 18:03:10  hhg
;; Added '?'s before single characters in define-keys for emacs19, at
;; Pascal Brisset's suggestion.
;;
;; Revision 1.52  1998/06/03 17:34:04  hhg
;; Added (require 'cl) for emacs19.
;;
;; Revision 1.51  1998/06/03 16:03:02  hhg
;; Added proof-goto-end-of-locked-interactive as old
;; proof-goto-end-of-locked, and proof-goto-end-of-locked now doesn't
;; switch buffer.
;;
;; Added code in proof-steal-process to handle case of stealing script
;; management from a killed buffer.
;;
;; Set proof-active-buffer-fake-minor-mode to nil in
;; proof-restart-script.
;;
;; Revision 1.50  1998/06/02 15:35:19  hhg
;; Generalized proof-retract-target, now parameterized by
;; proof-count-undos and proof-find-and-forget.
;; Generalized proof-shell-analyse-structure, introduced variable
;; proof-analyse-using-stack.
;; Generalized proof menu plus ancillary functions.
;; Generalized proof-mode-version-string.
;; Removed emacs-version-at-least.
;; Removed comment about buffer-display-table.
;; Moved various comments into documentation string.
;; Fixed another mode-line command for emacs19.
;;
;; Revision 1.49  1998/05/29 13:29:03  tms
;; fixed a bug in `proof-goto-end-of-locked-if-pos-not-visible-in-window'
;;
;; Revision 1.48  1998/05/29 09:50:01  tms
;; o outsourced indentation to proof-indent
;; o support indentation of commands
;; o replaced test of Emacs version with availability test of specific
;;   features
;; o C-c C-c, C-c C-v and M-tab is now available in all buffers
;;
;; Revision 1.47  1998/05/26 10:46:13  hhg
;; Removed commented code in proof-dont-show-annotations
;; proof-done-trying deletes the spans that were created
;;
;; Revision 1.46  1998/05/23 12:50:44  tms
;; improved support for Info
;;   o employed `Info-default-directory-list' rather than
;;     `Info-directory-list' so that code also works for Emacs 19.34
;;   o setting of `Info-default-directory-list' now at proof level
;;
;; Revision 1.45  1998/05/22 09:46:58  tms
;; fixed a bug in proof-frob-locked-end
;;
;; Revision 1.44  1998/05/21 17:34:31  hhg
;; Made proof-locked-span and proof-queue-span buffer-local.
;; Changed some if's without then-clauses to and's.
;; Removed (proof-detach-segments) from (proof-steal-process)
;; 	This is the bug that made changing buffers fail in emacs19:
;; 	the segments had already been detached.
;; Check if we're in proof buffer for proof-frob-locked-end.
;; Force mode-line update for emacs19 in proof-active-terminator-minor-mode.
;;
;; Revision 1.43  1998/05/19 15:30:03  hhg
;; Changed proof-indent-line code so that it doesn't modify buffer if
;; nothing is changed.
;; Changed proof-indent-region code so that the endpoints of the region
;; being indented change as indentation is done: it was infinite looping
;; because the end could never be reached.
;;
;; Revision 1.42  1998/05/15 16:23:53  hhg
;; Dependencies on versions of emacs have been moved to span-extent.el
;; and span-overlay.el.  Definitions of proof-queue-span and
;; proof-locked-span now in proof.el.
;;
;; Changed variable names [s]ext to span.
;;
;; Revision 1.41  1998/05/12 14:53:14  hhg
;; Added hook `proof-shell-insert-hook', to replace `proof-shell-config'.
;;
;; Revision 1.40  1998/05/08 17:10:11  hhg
;; Made separated indentation more elegant:
;; Made proof-assistant specific code into separate procedure,
;; 	proof-parse-indent.
;; Separated consideration of {}'s so it only happens for LEGO.
;;
;; Revision 1.39  1998/05/08 15:41:32  hhg
;; Merged indentation code for LEGO and Coq into proof.el.
;;
;; Fixed problem with active terminator mode: [proof-terminal-char] isn't
;; the same as (vector proof-terminal-char).
;;
;; Revision 1.38  1998/05/06 16:39:42  hhg
;; Fixed bug with inserting commands and proof-shell-config.
;;
;; Revision 1.37  1998/05/06 15:57:38  hhg
;; Removed proof-dependencies-emacs19 for the moment, since not having it
;; introduces error messages.
;; Put cd before init in proof-shell-config-done (this won't work for
;; Coq).
;;
;; Revision 1.36  1998/05/05 14:27:33  hhg
;; Updated to include changes for emacs19.
;; Also includes some changes for "Definition" problem in Coq, where
;; Definition couldn't be used for proof scripts.
;; Finally, modified proof-dependencies-xemacs code to fix problem that
;; undoing to (point-min) meant you couldn't type at first character.
;;
;; Revision 1.35  1998/03/25 17:30:28  tms
;; added support for etags at generic proof level
;;
;; Revision 1.34  1998/03/24 17:26:15  tms
;; *** empty log message ***
;;
;; Revision 1.33  1998/01/16 15:40:31  djs
;; Commented the code of proof.el and lego.el a bit. Made a minor change
;; to the way errors are handled, so that any delayed output is inserted
;; in the buffer before the error message is printed.
;;
;; Revision 1.32  1998/01/15 12:23:57  hhg
;; Updated method of defining proof-shell-cd to be consistent with other
;; proof-assistant-dependent variables.
;; Added ctrl-button1 to copy selected region to end of locked region
;;
;; Revision 1.31  1998/01/12 11:07:53  tms
;; o added support for remote proof processes
;; o bound C-c C-z to 'proof-frob-locked-end
;;
;; Revision 1.30  1998/01/05 15:01:31  tms
;; improved fume support
;;
;; Revision 1.29  1997/12/18 13:16:41  tms
;; o introduced proof-shell-handle-error-hook and bount it by default to
;;   proof-goto-end-of-locked-if-pos-not-visible-in-window (also new)
;;
;; o proof-find-next-terminator now also works inside a locked region
;;
;; o implemented proof-process-buffer which is by default bount to C-c C-b
;;
;; Revision 1.28  1997/11/26 14:19:45  tms
;; o The response buffer focusses on the first goal
;; o If proof-retract-until-point is is invoked outside a locked region,
;;   the last successfully processed command is undone.
;; o Added support for func-menu
;;
;; Revision 1.27  1997/11/24 19:15:16  djs
;; Added proof-execute-minibuffer-cmd and scripting minor mode.
;;
;; Revision 1.26  1997/11/20 16:47:48  hhg
;; Added proof-global-p to test whether a 'vanilla should be lifted above
;; active lemmas.
;; Separated proof-lift-global as separate command to lift global
;; declarations above active lemmas.
;; Fixed usual problem that 'cmd is nil for comments in this code.
;; Made lifting globals start from beginning of file rather than go
;; backwards.
;; Fixed bug in pbp code proof-shell-analyse-structure, where stack
;; wasn't cleared for new goal-hyp's.
;;
;; Revision 1.25  1997/11/17 17:11:21  djs
;; Added some magic commands: proof-frob-locked-end, proof-try-command,
;; proof-interrupt-process. Added moving nested lemmas above goal for coq.
;; Changed the key mapping for assert-until-point to C-c RET.
;;
;; Revision 1.24  1997/11/13 10:23:49  hhg
;; Includes commented code for Coq version of extent protocol
;;
;; Revision 1.23  1997/11/10 18:36:21  djs
;; Started modifications for emacs19 port.
;;
;; Revision 1.22  1997/11/10 15:51:09  djs
;; Put in a workaround for a strange bug in comint which was finding a bunch
;; of ^G's from comint-get-old-input for some inexplicable reason. THIS IS
;; STILL BROKEN AND A BUG REPORT HAS BEEN SUBMITTED TO XEMACS.ORG
;;
;; Revision 1.21  1997/11/06 16:56:59  hhg
;; Parameterize by proof-goal-hyp-fn in pbp-make-top-span, to handle
;; Coq goals which start with text rather than simply ?n
;;
;; Updated 'let (ap 0)' in proof-shell-analyse structure, to be slightly
;; more compatible with Coq pbp code
;;
;; Revision 1.20  1997/10/31 15:11:28  tms
;; o implemented proof-find-next-terminator available via C-c C-e
;; o fixed a bug in proof-done-retracting
;;
;; Revision 1.19  1997/10/30 15:58:33  hhg
;; Updates for coq, including:
;; 	* pbp-goal-command and pbp-hyp-command use proof-terminal-string
;; 	* updates to keywords
;; 	* fix for goal regexp
;;
;; Revision 1.18  1997/10/24 14:51:13  hhg
;; Updated comment about span types
;;
;; Revision 1.17  1997/10/22 16:43:54  hhg
;; Updated proof-segment-up-to to take ""'s into account
;; Hence, << Cd "../x". >> works in Coq, and
;;        << echo "hello; world"; >> should work in LEGO
;; But maybe we don't want "Cd"'s at all...
;;
;; Revision 1.16  1997/10/17 15:15:57  djs
;; proof-active-terminator inside comment case fixed. Also maybe the
;; continuous pbp-buffer update bug.
;;
;; Revision 1.15  1997/10/17 14:38:33  tms
;; fixed a bug in proof-process-active-terminator. Notice that it still
;; doesn't work when you are inside a comment and press the
;; proof-terminal-char
;;
;; Revision 1.14  1997/10/16 14:12:04  djs
;; Figured out display tables.
;;
;; Revision 1.13  1997/10/16 08:48:56  tms
;; merged script management (1.10.2.18) with main branch
;;
;; Revision 1.10.2.18  1997/10/14 19:30:55  djs
;; Bug fixes for comments.
;;
;; Revision 1.10.2.17  1997/10/14 17:30:15  djs
;; Fixed a bunch of bugs to do with comments, moved annotations out-of-band
;; to exploit a feature which will exist in XEmacs 20. (One day there *will
;; be* lemon-scented paper napkins). Added code to detect failing imports.
;;
;; Revision 1.10.2.16  1997/10/10 19:24:33  djs
;; Attempt to create a fresh branch because of Attic-Attack.
;;
;; Revision 1.10.2.15  1997/10/10 19:20:01  djs
;; Added multiple file support, changed the way comments work, fixed a
;; few minor bugs, and merged in coq support by hhg.
;;
;; Revision 1.10.2.13  1997/10/07 13:27:51  hhg
;; New structure sharing as much as possible between LEGO and Coq.
;;
;; Revision 1.10.2.12  1997/10/03 14:52:53  tms
;; o Replaced (string= "str" (substring cmd 0 n))
;;         by (string-match "^str" cmd)
;;   The latter doesn't raise an exception if cmd is too short
;;
;; o lego-count-undos: now depends on lego-undoable-commands-regexp
;;                     with special treatment of Equiv
;;
;; Revision 1.10.2.11  1997/09/19 11:23:23  tms
;; o replaced ?\; by proof-terminal-char
;; o fixed a bug in proof-process-active-terminator
;;
;; Revision 1.10.2.10  1997/09/12 12:33:41  tms
;; improved lego-find-and-forget
;;
;; Revision 1.10.2.9  1997/09/11 15:39:19  tms
;; fixed a bug in proof-retract-until-point
;;

(require 'cl)
(require 'compile)
(require 'comint)
(require 'etags)
(cond ((fboundp 'make-extent) (require 'span-extent))
      ((fboundp 'make-overlay) (require 'span-overlay))
      (t nil))
(require 'proof-fontlock)
(require 'proof-indent)
(require 'easymenu)

(autoload 'w3-fetch "w3" nil t)

(defmacro deflocal (var value docstring)
 (list 'progn
   (list 'defvar var 'nil docstring)
   (list 'make-variable-buffer-local (list 'quote var))
   (list 'setq var value)))


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;               Configuration                                      ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defconst proof-mode-version-string
  "PROOF-MODE. ALPHA Version 2 (June 1998) LEGO Team <lego@dcs.ed.ac.uk>")

(defvar proof-assistant ""
  "Name of the proof assistant")

(defvar proof-www-home-page ""
  "Web address for information on proof assistant")

(defvar proof-shell-cd nil
  "*Command of the inferior process to change the directory.") 

(defconst proof-info-dir "/usr/local/share/info")

(defvar proof-universal-keys
  (list (cons '[(control c) (control c)] 'proof-interrupt-process)
	(cons '[(control c) (control v)]
	      'proof-execute-minibuffer-cmd)
	(cons '[(meta tab)] 'tag-complete-symbol))
  "List of keybindings which are valid in both in the script and the
  response buffer. Elements of the list are tuples (k . f) 
  where `k' is a keybinding (vector) and `f' the designated function.")

(defvar proof-prog-name-ask-p nil
  "*If t, you will be asked which program to run when the inferior
 process starts up.")

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;  Other buffer-local variables used by proof mode                 ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;; These should be set before proof-config-done is called

(defvar proof-terminal-char nil "terminator character")

(defvar proof-comment-start nil "Comment start")
(defvar proof-comment-end nil "Comment end")

(defvar proof-save-command-regexp nil "Matches a save command")
(defvar proof-save-with-hole-regexp nil "Matches a named save command")
(defvar proof-goal-with-hole-regexp nil "Matches a saved goal command")

(defvar proof-goal-command-p nil "Is this a goal")
(defvar proof-count-undos-fn nil "Compute number of undos in a target segment")
(defvar proof-find-and-forget-fn nil "Compute command to forget up to point")
(defvar proof-goal-hyp-fn nil "Is point at goal or hypothesis")
(defvar proof-kill-goal-command nil "How to kill a goal.")
(defvar proof-global-p nil "Is this a global declaration")

(defvar proof-state-preserving-p nil
  "whether a command preserves the proof state")

(defvar pbp-change-goal nil
  "*Command to change to the goal %s")

;; these should be set in proof-pre-shell-start-hook

(defvar proof-prog-name nil "program name for proof shell")
(defvar proof-mode-for-shell nil "mode for proof shell")
(defvar proof-mode-for-pbp nil "The actual mode for Proof-by-Pointing.")
(defvar proof-shell-insert-hook nil 
  "Function to config proof-system to interface")

(defvar proof-pre-shell-start-hook)
(defvar proof-post-shell-exit-hook)

(defvar proof-shell-prompt-pattern nil 
   "comint-prompt-pattern for proof shell")

(defvar proof-shell-init-cmd nil
   "The command for initially configuring the proof process")

(defvar proof-shell-handle-delayed-output-hook
  '(proof-pbp-focus-on-first-goal)
  "*This hook is called after output from the PROOF process has been
  displayed in the RESPONSE buffer.")

(defvar proof-shell-handle-error-hook
  '(proof-goto-end-of-locked-if-pos-not-visible-in-window)
  "*This hook is called after an error has been reported in the
  RESPONSE buffer.")  

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;  Generic config for script management                            ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defvar proof-shell-wakeup-char nil
  "A character terminating the prompt in annotation mode")

(defvar proof-shell-annotated-prompt-regexp ""
  "Annotated prompt pattern")

(defvar proof-shell-abort-goal-regexp nil
  "*Regular expression indicating that the proof of the current goal
  has been abandoned.")

(defvar proof-shell-error-regexp nil
  "A regular expression indicating that the PROOF process has
  identified an error.") 

(defvar proof-shell-interrupt-regexp nil
  "A regular expression indicating that the PROOF process has
  responded to an interrupt.") 

(defvar proof-shell-proof-completed-regexp nil
  "*Regular expression indicating that the proof has been completed.")

(defvar proof-shell-result-start ""
  "String indicating the start of an output from the prover following
  a `pbp-goal-command' or a `pbp-hyp-command'.")

(defvar proof-shell-result-end ""
  "String indicating the end of an output from the prover following a
  `pbp-goal-command' or a `pbp-hyp-command'.") 

(defvar proof-shell-start-goals-regexp ""
  "String indicating the start of the proof state.")

(defvar proof-shell-end-goals-regexp ""
  "String indicating the end of the proof state.")

(defvar pbp-error-regexp nil
  "A regular expression indicating that the PROOF process has
  identified an error.") 

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;  Internal variables used by scripting and pbp                    ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defvar proof-shell-echo-input t
  "If nil, input to the proof shell will not be echoed")

(defvar proof-terminal-string nil 
  "You are not authorised for this information.")

(defvar proof-re-end-of-cmd nil 
  "You are not authorised for this information.")

(defvar proof-re-term-or-comment nil 
  "You are not authorised for this information.")

(defvar proof-marker nil 
  "You are not authorised for this information.")

(defvar proof-shell-buffer nil
  "You are not authorised for this information.")

(defvar proof-script-buffer nil
  "You are not authorised for this information.")

(defvar proof-pbp-buffer nil
  "You are not authorised for this information.")

(defvar proof-shell-busy nil 
  "You are not authorised for this information.")

(deflocal proof-buffer-type nil 
  "You are not authorised for this information.")

(defvar proof-action-list nil "action list")

(defvar proof-included-files-list nil 
  "Files currently included in proof process")

(deflocal proof-active-buffer-fake-minor-mode nil
  "An indication in the modeline that this is the *active* buffer")

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; A couple of small utilities                                      ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun proof-define-keys (map kbl)
  "Adds keybindings `kbl' in `map'. The argument `kbl' is a list of
  tuples (k . f) where `k' is a keybinding (vector) and `f' the
  designated function."
  (mapcar
   (lambda (kbl)
     (let ((k (car kbl)) (f (cdr kbl)))
         (define-key map k f)))
   kbl))

(defun proof-string-to-list (s separator) 
  "converts strings `s' separated by the character `separator' to a
  list of words" 
  (let ((end-of-word-occurence (string-match (concat separator "+") s)))
    (if (not end-of-word-occurence)
        (if (string= s "") 
            nil
          (list s))
      (cons (substring s 0 end-of-word-occurence) 
            (proof-string-to-list 
             (substring s
                        (string-match (concat "[^" separator "]")
                                      s end-of-word-occurence)) separator)))))

(defun w3-remove-file-name (address)
  "remove the file name in a World Wide Web address"
  (string-match "://[^/]+/" address)
  (concat (substring address 0 (match-end 0))
          (file-name-directory (substring address (match-end 0)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Basic code for the locked region and the queue region            ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defvar proof-locked-hwm nil
  "Upper limit of the locked region")

(defvar proof-queue-loose-end nil
  "Limit of the queue region that is not equal to proof-locked-hwm.")

(defvar proof-locked-span nil
  "Upper limit of the locked region")

(defvar proof-queue-span nil
  "Upper limit of the locked region")

(make-variable-buffer-local 'proof-locked-span)
(make-variable-buffer-local 'proof-queue-span)

(defun proof-init-segmentation ()
  (setq proof-queue-loose-end nil)
  (if (not proof-queue-span)
      (setq proof-queue-span (make-span 1 1)))
  (set-span-property proof-queue-span 'start-closed t)
  (set-span-property proof-queue-span 'end-open t)
  (span-read-only proof-queue-span)

  (make-face 'proof-queue-face)
  ;; Whether display has color or not
  (cond ((and (fboundp 'device-class)
	      (eq (device-class (frame-device)) 'color))
	 (set-face-background 'proof-queue-face "mistyrose"))
	((and (fboundp 'x-display-color-p) (x-display-color-p))
	 (set-face-background 'proof-queue-face "mistyrose"))
	(t (progn
	     (set-face-background 'proof-queue-face "Black")
	     (set-face-foreground 'proof-queue-face "White"))))
  (set-span-property proof-queue-span 'face 'proof-queue-face)

  (detach-span proof-queue-span)
  
  (setq proof-locked-hwm nil)
  (if (not proof-locked-span)
      (setq proof-locked-span (make-span 1 1)))
  (set-span-property proof-locked-span 'start-closed t)
  (set-span-property proof-locked-span 'end-open t)
  (span-read-only proof-locked-span)

  (make-face 'proof-locked-face)
  ;; Whether display has color or not
  (cond ((and (fboundp 'device-class)
	      (eq (device-class (frame-device)) 'color))
	 (set-face-background 'proof-locked-face "lavender"))
	((and (fboundp 'x-display-color-p) (x-display-color-p))
	 (set-face-background 'proof-locked-face "lavender"))
	(t (set-face-property 'proof-locked-face 'underline t)))
  (set-span-property proof-locked-span 'face 'proof-locked-face)

  (detach-span proof-locked-span))

(defsubst proof-lock-unlocked ()
  (span-read-only proof-locked-span))

(defsubst proof-unlock-locked ()
  (span-read-write proof-locked-span))

(defsubst proof-set-queue-endpoints (start end)
  (set-span-endpoints proof-queue-span start end))

(defsubst proof-set-locked-endpoints (start end)
  (set-span-endpoints proof-locked-span start end))

(defsubst proof-detach-queue ()
  (and proof-queue-span (detach-span proof-queue-span)))

(defsubst proof-detach-locked ()
  (and proof-locked-span (detach-span proof-locked-span)))

(defsubst proof-set-queue-start (start)
  (set-span-endpoints proof-queue-span start (span-end proof-queue-span)))

(defsubst proof-set-queue-end (end)
  (set-span-endpoints proof-queue-span (span-start proof-queue-span) end))

(defun proof-detach-segments ()
  (proof-detach-queue)
  (proof-detach-locked))

(defsubst proof-set-locked-end (end)
  (if (>= (point-min) end)
      (proof-detach-locked)
    (set-span-endpoints proof-locked-span (point-min) end)))

(defun proof-unprocessed-begin ()
  "proof-unprocessed-begin returns end of locked region in script
  buffer and point-min otherwise."
  (or 
   (and (eq proof-script-buffer (current-buffer))
	proof-locked-span (span-end proof-locked-span))
   (point-min)))

(defun proof-locked-end ()
  "proof-locked-end returns the end of the locked region.  It should
  only be called if we're in the scripting buffer."
  (if (eq proof-script-buffer (current-buffer))
      (proof-unprocessed-begin)
    (error "bug: proof-locked-end called from wrong buffer")))

(defsubst proof-end-of-queue ()
  (and proof-queue-span (span-end proof-queue-span)))

;;; This sets the display values of the annotations used to
;;; communicate with the proof assistant so that they don't show up on
;;; the screen.

(defun proof-dont-show-annotations ()
  (let ((disp (make-display-table))
	(i 128))
	(while (< i 256)
	  (aset disp i [])
	  (incf i))
	(cond ((fboundp 'add-spec-to-specifier)
	       (add-spec-to-specifier current-display-table disp
				      (current-buffer)))
	      ((boundp 'buffer-display-table)
	       (setq buffer-display-table disp)))))

;;; in case Emacs is not aware of read-shell-command-map

(defvar read-shell-command-map
  (let ((map (make-sparse-keymap)))
    (if (not (fboundp 'set-keymap-parents))
        (setq map (append minibuffer-local-map map))
      (set-keymap-parents map minibuffer-local-map)
      (set-keymap-name map 'read-shell-command-map))
    (define-key map "\t" 'comint-dynamic-complete)
    (define-key map "\M-\t" 'comint-dynamic-complete)
    (define-key map "\M-?" 'comint-dynamic-list-completions)
    map)
  "Minibuffer keymap used by shell-command and related commands.")


;;; in case Emacs is not aware of the function read-shell-command
(or (fboundp 'read-shell-command)
    ;; from minibuf.el distributed with XEmacs 19.11
    (defun read-shell-command (prompt &optional initial-input history)
      "Just like read-string, but uses read-shell-command-map:
\\{read-shell-command-map}"
      (let ((minibuffer-completion-table nil))
        (read-from-minibuffer prompt initial-input read-shell-command-map
                              nil (or history
                              'shell-command-history)))))

;; The package fume-func provides a function with the same name and
;; specification. However, fume-func's version is incorrect.
(and (fboundp 'fume-match-find-next-function-name)
(defun fume-match-find-next-function-name (buffer)
  "General next function name in BUFFER finder using match.
  The regexp is assumed to be a two item list the car of which is the regexp
  to use, and the cdr of which is the match position of the function name"
  (set-buffer buffer)
  (let ((r (car fume-function-name-regexp))
        (p (cdr fume-function-name-regexp)))
    (and (re-search-forward r nil t)
	 (cons (buffer-substring (setq p (match-beginning p)) (point)) p)))))

(defun proof-goto-end-of-locked-interactive ()
  "Jump to the end of the locked region."
  (interactive)
  (switch-to-buffer proof-script-buffer)
  (goto-char (proof-locked-end)))

(defun proof-goto-end-of-locked ()
  "Jump to the end of the locked region."
  (goto-char (proof-locked-end)))

(defun proof-goto-end-of-locked-if-pos-not-visible-in-window ()
  "If the end of the locked region is not visible, jump to the end of
  the locked region."
  (interactive)
  (let ((pos (save-excursion
	       (set-buffer proof-script-buffer)
	       (proof-locked-end))))
    (or (pos-visible-in-window-p pos (get-buffer-window
				      proof-script-buffer t))
        (proof-goto-end-of-locked-interactive))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;  Starting and stopping the proof-system shell                    ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun proof-shell-live-buffer () 
  (and proof-shell-buffer
       (comint-check-proc proof-shell-buffer)
       proof-shell-buffer))

(defun proof-start-shell ()
  (if (proof-shell-live-buffer)
      ()
    (run-hooks 'proof-pre-shell-start-hook)
    (setq proof-included-files-list nil)
    (if proof-prog-name-ask-p
	(save-excursion
	  (setq proof-prog-name (read-shell-command "Run process: "
						    proof-prog-name))))
    (let ((proc
	   (concat "Inferior "
		   (substring proof-prog-name
			      (string-match "[^/]*$" proof-prog-name)))))
      (while (get-buffer (concat "*" proc "*"))
	(if (string= (substring proc -1) ">")
	    (aset proc (- (length proc) 2) 
		  (+ 1 (aref proc (- (length proc) 2))))
	  (setq proc (concat proc "<2>"))))

      (message (format "Starting %s process..." proc))

      ;; Starting the inferior process (asynchronous)
      (let ((prog-name-list (proof-string-to-list proof-prog-name " ")))
	(apply 'make-comint  (append (list proc (car prog-name-list) nil)
				     (cdr prog-name-list))))
      ;; To send any initialisation commands to the inferior process,
      ;; consult proof-shell-config-done...

      (setq proof-shell-buffer (get-buffer (concat "*" proc "*")))
      (setq proof-pbp-buffer (get-buffer-create (concat "*" proc "-goals*")))

      (save-excursion
	(set-buffer proof-shell-buffer)
	(funcall proof-mode-for-shell)
	(set-buffer proof-pbp-buffer)
	(funcall proof-mode-for-pbp))

      (setq proof-script-buffer (current-buffer))
      (proof-init-segmentation)
      (setq proof-active-buffer-fake-minor-mode t)

      (if (fboundp 'redraw-modeline)
	  (redraw-modeline)
	(force-mode-line-update))

      (or (assq 'proof-active-buffer-fake-minor-mode minor-mode-alist)
	  (setq minor-mode-alist
		(append minor-mode-alist
			(list '(proof-active-buffer-fake-minor-mode 
				" Scripting")))))

      (message 
       (format "Starting %s process... done." proc)))))
  

(defun proof-stop-shell ()
  "Exit the PROOF process

  Runs proof-shell-exit-hook if non nil"

  (interactive)
  (save-excursion
    (let ((buffer (proof-shell-live-buffer)) (proc))
      (if buffer
	  (progn
	    (save-excursion
	      (set-buffer buffer)
	      (setq proc (process-name (get-buffer-process)))
	      (comint-send-eof)
	      (save-excursion
		(set-buffer proof-script-buffer)
		(proof-detach-segments))
	      (kill-buffer))
	    (run-hooks 'proof-shell-exit-hook)

             ;;it is important that the hooks are
	     ;;run after the buffer has been killed. In the reverse
	     ;;order e.g., intall-shell-fonts causes problems and it
	     ;;is impossible to restart the PROOF shell

	    (message (format "%s process terminated." proc)))))))


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;          Proof by pointing                                       ;;
;;          All very lego-specific at present                       ;;
;;          To make sense of this code, you should read the         ;;
;;          relevant LFCS tech report by tms, yb, and djs           ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;


(defvar pbp-goal-command nil
  "Command informing the prover that `pbp-button-action' has been
  requested on a goal.")

(defvar pbp-hyp-command nil
  "Command informing the prover that `pbp-button-action' has been
  requested on an assumption.")

(defun pbp-button-action (event)
   (interactive "e")
   (mouse-set-point event)
   (pbp-construct-command))

; Using the spans in a mouse behavior is quite simple: from the
; mouse position, find the relevant span, then get its annotation
; and produce a piece of text that will be inserted in the right
; buffer.  

(defun proof-expand-path (string)
  (let ((a 0) (l (length string)) ls)
    (while (< a l) 
      (setq ls (cons (int-to-string (aref string a)) 
		     (cons " " ls)))
      (incf a))
    (apply 'concat (nreverse ls))))

(defun proof-send-span (event)
  (interactive "e")
  (let* ((span (span-at (mouse-set-point event) 'type))
	 (str (span-property span 'cmd)))
    (cond ((and (eq proof-script-buffer (current-buffer)) (not (null span)))
	   (proof-goto-end-of-locked)
	   (cond ((eq (span-property span 'type) 'vanilla)
		  (insert str)))))))

(defun pbp-construct-command ()
  (let* ((span (span-at (point) 'proof))
	 (top-span (span-at (point) 'proof-top-element))
	 top-info)
    (if (null top-span) ()
      (setq top-info (span-property top-span 'proof-top-element))
      (pop-to-buffer proof-script-buffer)
      (cond
       (span
	(proof-invisible-command 
	 (format (if (eq 'hyp (car top-info)) pbp-hyp-command 
		                              pbp-goal-command)
		 (concat (cdr top-info) (proof-expand-path 
					 (span-property span 'proof))))))
       ((eq (car top-info) 'hyp)
	(proof-invisible-command (format pbp-hyp-command (cdr top-info))))
       (t
	 (proof-insert-pbp-command (format pbp-change-goal (cdr top-info))))))
    ))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;          Turning annotated output into pbp goal set              ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defvar proof-shell-first-special-char nil "where the specials start")
(defvar proof-shell-goal-char nil "goal mark")
(defvar proof-shell-start-char nil "annotation start")
(defvar proof-shell-end-char nil "annotation end")
(defvar proof-shell-field-char nil "annotated field end")
(defvar proof-shell-eager-annotation-start nil "eager ann. field start")
(defvar proof-shell-eager-annotation-end nil "eager ann. field end")

(defvar proof-shell-assumption-regexp nil
  "A regular expression matching the name of assumptions.")

(defvar proof-shell-goal-regexp nil
  "A regular expressin matching the identifier of a goal.")

(defvar proof-shell-noise-regexp nil
  "Unwanted information output from the proof process within
  `proof-start-goals-regexp' and `proof-end-goals-regexp'.")

(defun pbp-make-top-span (start end)
  (let (span name)
    (goto-char start)
    (setq name (funcall proof-goal-hyp-fn))
    (beginning-of-line)
    (setq start (point))
    (goto-char end)
    (beginning-of-line)
    (backward-char)
    (setq span (make-span start (point)))
    (set-span-property span 'mouse-face 'highlight)
    (set-span-property span 'proof-top-element name)))


;; Need this for processing error strings and so forth

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;   The filter. First some functions that handle those few         ;;
;;   occasions when the glorious illusion that is script-management ;;
;;   is temporarily suspended                                       ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;   Output from the proof process is handled lazily, so that only  
;;   the output from the last of multiple commands is actually      
;;   processed (assuming they're all successful)                    

(defvar proof-shell-delayed-output nil
  "The last interesting output the proof process output, and what to do
   with it.")

(defvar proof-analyse-using-stack nil
  "Are annotations sent by proof assistant local or global")

(defun proof-shell-analyse-structure (string)
  (save-excursion
    (let* ((ip 0) (op 0) ap (l (length string)) 
	   (ann (make-string (length string) ?x))
           (stack ()) (topl ()) 
	   (out (make-string l ?x)) c span)
      (while (< ip l)	
	(if (< (setq c (aref string ip)) 128)
	    (progn (aset out op c)
		   (incf op)))
	(incf ip))
      (display-buffer (set-buffer proof-pbp-buffer))
      (erase-buffer)
      (insert (substring out 0 op))

      (setq ip 0
	    op 1)
      (while (< ip l)
	(setq c (aref string ip))
	(cond
	 ((= c proof-shell-goal-char)
	  (setq topl (cons op topl))
	  (setq ap 0))
	 ((= c proof-shell-start-char)
	  (if proof-analyse-using-stack
	      (setq ap (- ap (- (aref string (incf ip)) 128)))
	    (setq ap (- (aref string (incf ip)) 128)))
	  (incf ip)
	  (while (not (= (setq c (aref string ip)) proof-shell-end-char))
	    (aset ann ap (- c 128))
	    (incf ap)
	    (incf ip))
	  (setq stack (cons op (cons (substring ann 0 ap) stack))))
	 ((= c proof-shell-field-char)
	  (setq span (make-span (car stack) op))
	  (set-span-property span 'mouse-face 'highlight)
	  (set-span-property span 'proof (car (cdr stack)))
	  ;; Pop annotation off stack
	  (and proof-analyse-using-stack
	       (progn
		 (setq ap 0)
		 (while (< ap (length (cadr stack)))
		   (aset ann ap (aref (cadr stack) ap))
		   (incf ap))))
	  ;; Finish popping annotations
	  (setq stack (cdr (cdr stack))))
	 (t (incf op)))
	(incf ip))
      (setq topl (reverse (cons (point-max) topl)))
      ;; If we want Coq pbp: (setq coq-current-goal 1)
      (while (setq ip (car topl) 
		   topl (cdr topl))
	(pbp-make-top-span ip (car topl))))))

(defun proof-shell-strip-annotations (string)
  (let* ((ip 0) (op 0) (l (length string)) (out (make-string l ?x )))
    (while (< ip l)
      (if (>= (aref string ip) proof-shell-first-special-char)
	  (if (char-equal (aref string ip) proof-shell-start-char)
	      (progn (incf ip)
		     (while (< (aref string ip) proof-shell-first-special-char)
		       (incf ip))))
	(aset out op (aref string ip))
	(incf op))
      (incf ip))
    (substring out 0 op)))

(defun proof-shell-handle-delayed-output ()
  (let ((ins (car proof-shell-delayed-output))
	(str (cdr proof-shell-delayed-output)))
    (display-buffer proof-pbp-buffer)
    (save-excursion
      (cond 
       ((eq ins 'insert)
	(setq str (proof-shell-strip-annotations str))
	(set-buffer proof-pbp-buffer)
	(erase-buffer)
	(insert str))
       ((eq ins 'analyse)
	(proof-shell-analyse-structure str))
       (t (set-buffer proof-pbp-buffer)
	  (insert "\n\nbug???")))))
  (run-hooks 'proof-shell-handle-delayed-output-hook)
  (setq proof-shell-delayed-output (cons 'insert "done")))

(defun proof-shell-handle-error (cmd string)
  (save-excursion
    (display-buffer (set-buffer proof-pbp-buffer))
    (if (not (eq proof-shell-delayed-output (cons 'insert "done")))
	(progn
	  (set-buffer proof-pbp-buffer)
	  (erase-buffer)
	  (insert (proof-shell-strip-annotations 
		   (cdr proof-shell-delayed-output)))))
    (goto-char (point-max))
    (if (re-search-backward pbp-error-regexp nil t) 
	(delete-region (- (point) 2) (point-max)))
    (newline 2)
    (insert-string string)
    (beep))
  (set-buffer proof-script-buffer)
  (proof-detach-queue)
  (delete-spans (proof-locked-end) (point-max) 'type)
  (proof-release-lock)
  (run-hooks 'proof-shell-handle-error-hook))

(defun proof-shell-handle-interrupt ()
  (save-excursion 
    (display-buffer (set-buffer proof-pbp-buffer))
    (goto-char (point-max))
    (newline 2)
    (insert-string 
     "Interrupt: Script Management may be in an inconsistent state\n")
    (beep))
  (set-buffer proof-script-buffer)
  (if proof-shell-busy
      (progn (proof-detach-queue)
	     (delete-spans (proof-locked-end) (point-max) 'type)
	     (proof-release-lock))))


(defun proof-goals-pos (span maparg)
  "Given a span, this function returns the start of it if corresponds
  to a goal and nil otherwise."
 (and (eq 'goal (car (span-property span 'proof-top-element)))
		(span-start span)))

(defun proof-pbp-focus-on-first-goal ()
  "If the `proof-pbp-buffer' contains goals, the first one is brought
  into view."
  (and (fboundp 'map-extents)
       (let
	   ((pos (map-extents 'proof-goals-pos proof-pbp-buffer
			      nil nil nil nil 'proof-top-element)))
	 (and pos (set-window-point
		   (get-buffer-window proof-pbp-buffer t) pos)))))

;;   The basic output processing function - it can return one of 4  ;;  
;;   things: 'error, 'interrupt, 'loopback, or nil. 'loopback means ;;
;;   this was output from pbp, and should be inserted into the      ;;
;;   script buffer and sent back to the proof assistant             ;;

(defun proof-shell-process-output (cmd string)
  (cond 
   ((string-match proof-shell-error-regexp string)
    (cons 'error (proof-shell-strip-annotations 
		  (substring string (match-beginning 0)))))

   ((string-match proof-shell-interrupt-regexp string)
    'interrupt)

   ((string-match proof-shell-abort-goal-regexp string)
    (setq proof-shell-delayed-output (cons 'insert "\n\nAborted"))
    ())
	 
   ((string-match proof-shell-proof-completed-regexp string)
    (setq proof-shell-delayed-output
	  (cons 'insert (concat "\n" (match-string 0 string)))))

   ((string-match proof-shell-start-goals-regexp string)
    (let (start end)
      (while (progn (setq start (match-end 0))
		    (string-match proof-shell-start-goals-regexp 
				  string start)))
      (setq end (string-match proof-shell-end-goals-regexp string start))
      (setq proof-shell-delayed-output 
	    (cons 'analyse (substring string start end)))))
       
   ((string-match proof-shell-result-start string)
    (let (start end)
      (setq start (+ 1 (match-end 0)))
      (string-match proof-shell-result-end string)
      (setq end (- (match-beginning 0) 1))
      (cons 'loopback (substring string start end))))
   
   ((string-match "^Module" cmd)
    (setq proof-shell-delayed-output (cons 'insert "Imports done!")))

   (t (setq proof-shell-delayed-output (cons 'insert string)))))
         
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;   Low-level commands for shell communication                     ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun proof-shell-insert (string)
  (set-buffer proof-shell-buffer)
  (goto-char (point-max))

  (run-hooks 'proof-shell-insert-hook)
  (insert string)

  ;; xemacs and emacs19 have different semantics for what happens when
  ;; shell input is sent next to a marker
  ;; the following code accommodates both definitions
  (if (marker-position proof-marker)
      (let ((inserted (point)))
	(comint-send-input)
	(set-marker proof-marker inserted))
    (comint-send-input)))

(defun proof-send (string)
  (let ((l (length string)) (i 0))
    (while (< i l)
      (if (= (aref string i) ?\n) (aset string i ?\ ))
      (incf i)))
  (save-excursion (proof-shell-insert string)))

;; Note that this is not really intended for anything complicated -
;; just to stop the user accidentally sending a command while the
;; queue is running.
(defun proof-check-process-available (&optional relaxed)
  "Checks
     (1) Is a proof process running?
     (2) Is the proof process idle?
     (3) Does the current buffer own the proof process?
     (4) Is the current buffer a proof script?
    and signals an error if at least one of the conditions is not
    fulfilled. If relaxed is set, only (1) and (2) are tested."
  (if (proof-shell-live-buffer)
      (cond
       (proof-shell-busy (error "Proof Process Busy!"))
       (relaxed ())			;exit cond
       ((not (eq proof-script-buffer (current-buffer)))
	(error "Don't own proof process"))))
  (if (not (or relaxed (eq proof-buffer-type 'script)))
      (error "Must be running in a script buffer")))

(defun proof-grab-lock (&optional relaxed)
  (proof-start-shell)
  (proof-check-process-available relaxed)
  (setq proof-shell-busy t))

(defun proof-release-lock ()
  (if (proof-shell-live-buffer)
      (progn
	(if (not proof-shell-busy)
	    (error "Bug: Proof process not busy"))
	(if (not (eq proof-script-buffer (current-buffer)))
	    (error "Bug: Don't own process"))
	(setq proof-shell-busy nil))))

; Pass start and end as nil if the cmd isn't in the buffer.

(defun proof-start-queue (start end alist &optional relaxed)
  (if start
      (proof-set-queue-endpoints start end))
  (let (item)
    (while (and alist (string= 
		       (nth 1 (setq item (car alist))) 
		       "COMMENT"))
    (funcall (nth 2 item) (car item))
    (setq alist (cdr alist)))
  (if alist
      (progn
	(proof-grab-lock relaxed) 
	(setq proof-shell-delayed-output (cons 'insert "Done."))
	(setq proof-action-list alist)
	(proof-send (nth 1 item))))))

; returns t if it's run out of input

(defun proof-shell-exec-loop ()
  (save-excursion
    (set-buffer proof-script-buffer)
    (if (null proof-action-list) (error "Non Sequitur"))
    (let ((item (car proof-action-list)))
      (funcall (nth 2 item) (car item))
      (setq proof-action-list (cdr proof-action-list))
      (while (and proof-action-list
		(string= 
		 (nth 1 (setq item (car proof-action-list))) 
		 "COMMENT"))
	(funcall (nth 2 item) (car item))
	(setq proof-action-list (cdr proof-action-list)))
      (if (null proof-action-list)
	  (progn (proof-release-lock)
		 (proof-detach-queue)
		 t)
	(proof-send (nth 1 item))
	nil))))

(defun proof-shell-insert-loopback-cmd  (cmd)
  "Insert command sequence triggered by the proof process
at the end of locked region (after inserting a newline and indenting)."
  (save-excursion
    (set-buffer proof-script-buffer)
    (let (span)
      (proof-goto-end-of-locked)
      (newline-and-indent)
      (insert cmd)
      (setq span (make-span (proof-locked-end) (point)))
      (set-span-property span 'type 'pbp)
      (set-span-property span 'cmd cmd)
      (proof-set-queue-endpoints (proof-locked-end) (point))
      (setq proof-action-list 
	    (cons (car proof-action-list) 
		  (cons (list span cmd 'proof-done-advancing)
			(cdr proof-action-list)))))))

;; ******** NB **********
;;  While we're using pty communication, this code is OK, since all
;; eager annotations are one line long, and we get input a line at a
;; time. If we go over to piped communication, it will break.

(defun proof-shell-popup-eager-annotation ()
  "Eager annotations are annotations which the proof system produces
while it's doing something (e.g. loading libraries) to say how much
progress it's made. Obviously we need to display these as soon as they
arrive."
  (let (mrk str file module)
    (save-excursion 
      (goto-char (point-max))
      (search-backward proof-shell-eager-annotation-start)
      (setq mrk (+ 1 (point)))
      (search-forward proof-shell-eager-annotation-end)
      (setq str (buffer-substring mrk (- (point) 1)))
      (display-buffer (set-buffer proof-pbp-buffer))
      (goto-char (point-max))
      (insert str "\n"))
    (if (string-match "Creating mark \"\\(.*\\)\" \\[\\(.*\\)\\]" str)
	(progn
	  (setq file (match-string 2 str)
		module (match-string 1 str))
	  (if (string= file "") 
	      (setq file (buffer-file-name proof-script-buffer)))
	  (setq file (expand-file-name file))
	  (if (string-match "\\(.*\\)\\.." file)
	      (setq file (match-string 1 file)))
	  (setq proof-included-files-list (cons (cons module file)
						proof-included-files-list))))))

(defun proof-shell-filter (str) 
  "The filter for the shell-process. We sleep until we get a
  wakeup-char in the input, then run proof-shell-process-output, and
  set proof-marker to keep track of how far we've got."
  (if (string-match proof-shell-eager-annotation-end str)
      (proof-shell-popup-eager-annotation))
  (if (string-match (char-to-string proof-shell-wakeup-char) str)
      (if (null (marker-position proof-marker))
	  (progn
	    (goto-char (point-min))
	    (re-search-forward proof-shell-annotated-prompt-regexp)
	    (backward-delete-char 1)
	    (set-marker proof-marker (point)))
	(let (string res cmd)	
	  (goto-char (marker-position proof-marker))
	  (re-search-forward proof-shell-annotated-prompt-regexp nil t)
	  (backward-char (- (match-end 0) (match-beginning 0)))
	  (setq string (buffer-substring (marker-position proof-marker)
					 (point)))
	  (goto-char (point-max))
	  (backward-delete-char 1)
	  (setq cmd (nth 1 (car proof-action-list)))
	  (save-excursion
	    (setq res (proof-shell-process-output cmd string))
	    (cond
	     ((and (consp res) (eq (car res) 'error))
	      (proof-shell-handle-error cmd (cdr res)))
	     ((eq res 'interrupt)
	      (proof-shell-handle-interrupt))
	     ((and (consp res) (eq (car res) 'loopback))
	      (proof-shell-insert-loopback-cmd (cdr res))
	      (proof-shell-exec-loop))
	     (t (if (proof-shell-exec-loop)
		    (proof-shell-handle-delayed-output)))))))))

(defun proof-last-goal-or-goalsave ()
  (save-excursion
    (let ((span (span-at-before (proof-locked-end) 'type)))
    (while (and span 
		(not (eq (span-property span 'type) 'goalsave))
		(or (eq (span-property span 'type) 'comment)
		    (not (funcall proof-goal-command-p
				       (span-property span 'cmd)))))
      (setq span (prev-span span 'type)))
    span)))
    
;; This needs some work to make it generic, since most of the code
;; doesn't apply to Coq at all.
(defun proof-steal-process ()
  "This allows us to steal the process if we want to change the buffer
   in which script management is running."
  (proof-start-shell)
  (if proof-shell-busy (error "Proof Process Busy!"))
  (if (not (eq proof-buffer-type 'script))
      (error "Must be running in a script buffer"))
  (cond
   ((eq proof-script-buffer (current-buffer))
    nil)
   (t
    (let ((flist proof-included-files-list) 
	  (file (expand-file-name (buffer-file-name))) span (cmd ""))
      (if (string-match "\\(.*\\)\\.." file) (setq file (match-string 1 file)))
      (while (and flist (not (string= file (cdr (car flist)))))
	(setq flist (cdr flist)))
      (if (null flist) 
	  (if (not (y-or-n-p "Steal script management? " )) (error "Aborted"))
	(if (not (y-or-n-p "Reprocess this file? " )) (error "Aborted")))
      (if (not (buffer-name proof-script-buffer))
	  (message "Warning: Proof script buffer deleted: proof state may be inconsistent")
	(save-excursion
	  (set-buffer proof-script-buffer)
	  (setq proof-active-buffer-fake-minor-mode nil)
	  (setq span (proof-last-goal-or-goalsave))
	  ;; This won't work for Coq if we have recursive goals in progress
	  (if (and span (not (eq (span-property span 'type) 'goalsave)))
	      (setq cmd proof-kill-goal-command))
	  (proof-detach-segments)
	  (delete-spans (point-min) (point-max) 'type)))

      (setq proof-script-buffer (current-buffer))
      (proof-init-segmentation)
      (setq proof-active-buffer-fake-minor-mode t)

      (cond 
       (flist
	(list nil (concat cmd "ForgetMark " (car (car flist)) ";")
	      `(lambda (span) (setq proof-included-files-list 
				    (quote ,(cdr flist))))))
       ((not (string= cmd ""))
	(list nil cmd 'proof-done-invisible))
       (t nil))))))

(defun proof-done-invisible (span) ())

(defun proof-invisible-command (cmd &optional relaxed)
  "Send cmd to the proof process without responding to the user."
  (proof-check-process-available relaxed)
  (if (not (string-match proof-re-end-of-cmd cmd))
      (setq cmd (concat cmd proof-terminal-string)))
  (proof-start-queue nil nil (list (list nil cmd
  'proof-done-invisible)) relaxed))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;          User Commands                                           ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
	
; Script management uses two major segments: Locked, which marks text
; which has been sent to the proof assistant and cannot be altered
; without being retracted, and Queue, which contains stuff being
; queued for processing.  proof-action-list contains a list of
; (span,command,action) triples. The loop looks like: Execute the
; command, and if it's successful, do action on span.  If the
; command's not successful, we bounce the rest of the queue and do
; some error processing.
;
; when a span has been processed, we classify it as follows:
; 'goalsave - denoting a 'goalsave pair in the locked region
;    a 'goalsave region has a 'name property which is the name of the goal
; 'comment - denoting a comment
; 'pbp - denoting a span created by pbp
; 'vanilla - denoting any other span.
;   'pbp & 'vanilla spans have a property 'cmd, which says what
;   command they contain. 

; We don't allow commands while the queue has anything in it.  So we
; do configuration by concatenating the config command on the front in
; proof-send

;;         proof-assert-until-point, and various gunk for its       ;;
;;         setup and callback                                       ;;

;; This code is for nested goals in Coq, and shouldn't affect things
;; in LEGO.  It lifts "local" lemmas from inside goals out to top
;; level.

(defun proof-lift-global (glob-span)
  (let (start (next (span-at 1 'type)) str (goal-p nil))
    (while (and next (and (not (eq next glob-span)) (not goal-p)))
      (if (and (eq (span-property next 'type) 'vanilla)
	       (funcall proof-goal-command-p (span-property next 'cmd)))
	  (setq goal-p t)
	(setq next (next-span next 'type))))

    (if (and next (not (eq next glob-span)))
	(progn
	  (proof-unlock-locked)
	  (setq str (buffer-substring (span-start glob-span)
				      (span-end glob-span)))
	  (delete-region (span-start glob-span) (span-end glob-span))
	  (goto-char (span-start next))
	  (setq start (point))
	  (insert str "\n")
	  (set-span-endpoints glob-span start (point))
	  (set-span-start next (point))
	  (proof-lock-unlocked)))))

;; This is the actual callback for assert-until-point.

(defun proof-done-advancing (span)
  (let ((end (span-end span)) nam gspan next cmd)
    (proof-set-locked-end end)
    (proof-set-queue-start end)
    (setq cmd (span-property span 'cmd))
    (cond
     ((eq (span-property span 'type) 'comment)
      (set-span-property span 'mouse-face 'highlight))
     ((string-match proof-save-command-regexp cmd)
      ;; In coq, we have the invariant that if we've done a save and
      ;; there's a top-level declaration then it must be the
      ;; associated goal.  (Notice that because it's a callback it
      ;; must have been approved by the theorem prover.)
      (if (string-match proof-save-with-hole-regexp cmd)
	  (setq nam (match-string 2 cmd)))
      (setq gspan span)
      (while (or (eq (span-property gspan 'type) 'comment)
		 (not (funcall proof-goal-command-p 
				    (setq cmd (span-property gspan 'cmd)))))
	(setq next (prev-span gspan 'type))
	(delete-span gspan)
	(setq gspan next))

      (if (null nam)
	  (if (string-match proof-goal-with-hole-regexp
			    (span-property gspan 'cmd))
	      (setq nam (match-string 2 (span-property gspan 'cmd)))
	    ;; This only works for Coq, but LEGO raises an error if
	    ;; there's no name.
	    (setq nam "Unnamed_thm")))

      (set-span-end gspan end)
      (set-span-property gspan 'mouse-face 'highlight)
      (set-span-property gspan 'type 'goalsave)
      (set-span-property gspan 'name nam)

      (proof-lift-global gspan))
     (t
      (set-span-property span 'mouse-face 'highlight)
      (if (funcall proof-global-p cmd)
	  (proof-lift-global span))))))

; depth marks number of nested comments. quote-parity is false if
; we're inside ""'s.  Only one of (depth > 0) and (not quote-parity)
; should be true at once. -- hhg

(defun proof-segment-up-to (pos)
  "Create a list of (type,int,string) pairs from the end of the locked
region to pos, denoting the command and the position of its
terminator. type is one of comment, or cmd. 'unclosed-comment may be
consed onto the start if the segment finishes with an unclosed
comment."
  (save-excursion
    (let ((str (make-string (- (buffer-size) (proof-locked-end) -10) ?x))
	  (i 0) (depth 0) (quote-parity t) done alist c)
     (proof-goto-end-of-locked)
     (while (not done)
       (cond 
	((and (= (point) pos) (> depth 0))
	 (setq done t alist (cons 'unclosed-comment alist)))
	((= (point) (point-max))
	 (if (not quote-parity)
	     (message "Warning: unclosed quote"))
	 (setq done t))
	((and (looking-at "\\*)") quote-parity)
	 (if (= depth 0) 
	     (progn (message "Warning: extraneous comment end") (setq done t))
	   (setq depth (- depth 1)) (forward-char 2)
	   (if (eq i 0) 
	       (setq alist (cons (list 'comment "" (point)) alist))
	     (aset str i ?\ ) (incf i))))
	((and (looking-at "(\\*") quote-parity)
	 (setq depth (+ depth 1)) (forward-char 2))
	((> depth 0) (forward-char))
	(t
	 (setq c (char-after (point)))
	 (if (or (> i 0) (not (= (char-syntax c) ?\ )))
	     (progn (aset str i c) (incf i)))
	 (if (looking-at "\"")
	     (setq quote-parity (not quote-parity)))
	 (forward-char)
	 (if (and (= c proof-terminal-char) quote-parity)
	     (progn 
	       (setq alist 
		     (cons (list 'cmd (substring str 0 i) (point)) alist))
	       (if (>= (point) pos) (setq done t) (setq i 0)))))))
     alist)))

(defun proof-semis-to-vanillas (semis &optional callback-fn)
  "Convert a sequence of semicolon positions (returned by the above
function) to a set of vanilla extents."
  (let ((ct (proof-locked-end)) span alist semi)
    (while (not (null semis))
      (setq semi (car semis)
            span (make-span ct (nth 2 semi))
	    ct (nth 2 semi))
      (if (eq (car (car semis)) 'cmd)
	  (progn
	    (set-span-property span 'type 'vanilla)
	    (set-span-property span 'cmd (nth 1 semi))
	    (setq alist (cons (list span (nth 1 semi) 
				    (or callback-fn 'proof-done-advancing))
			      alist)))
	(set-span-property span 'type 'comment)
	(setq alist (cons (list span "COMMENT" 'proof-done-advancing) alist)))
	(setq semis (cdr semis)))
    (nreverse alist)))

; Assert until point - We actually use this to implement the 
; assert-until-point, active terminator keypress, and find-next-terminator. 
; In different cases we want different things, but usually the information
; (i.e. are we inside a comment) isn't available until we've actually run
; proof-segment-up-to (point), hence all the different options when we've
; done so.

(defun proof-assert-until-point
  (&optional unclosed-comment-fun ignore-proof-process-p)
  "Process the region from the end of the locked-region until point.
   Default action if inside a comment is just to go until the start of
   the comment. If you want something different, put it inside
   unclosed-comment-fun. If ignore-proof-process-p is set, no commands
   will be added to the queue."
  (interactive)
  (let ((pt (point))
	(crowbar (or ignore-proof-process-p (proof-steal-process)))
	semis)
    (save-excursion
      (if (not (re-search-backward "\\S-" (proof-locked-end) t))
	  (progn (goto-char pt)
		 (error "Nothing to do!")))
      (setq semis (proof-segment-up-to (point))))
    (if (and unclosed-comment-fun (eq 'unclosed-comment (car semis)))
	(funcall unclosed-comment-fun)
      (if (eq 'unclosed-comment (car semis)) (setq semis (cdr semis)))
      (if (and (not ignore-proof-process-p) (not crowbar) (null semis))
	  (error "Nothing to do!"))
      (goto-char (nth 2 (car semis)))
      (and (not ignore-proof-process-p)
	   (let ((vanillas (proof-semis-to-vanillas (nreverse semis))))
	     (if crowbar (setq vanillas (cons crowbar vanillas)))
	     (proof-start-queue (proof-locked-end) (point) vanillas))))))

;;         insert-pbp-command - an advancing command, for use when  ;;
;;         PbpHyp or Pbp has executed in LEGO, and returned a       ;;
;;         command for us to run                                    ;;

(defun proof-insert-pbp-command (cmd)
  (proof-check-process-available)
  (let (span)
    (proof-goto-end-of-locked)
    (insert cmd)
    (setq span (make-span (proof-locked-end) (point)))
    (set-span-property span 'type 'pbp)
    (set-span-property span 'cmd cmd)
    (proof-start-queue (proof-locked-end) (point) 
		       (list (list span cmd 'proof-done-advancing)))))


;;         proof-retract-until-point and associated gunk            ;;
;;         most of the hard work (i.e computing the commands to do  ;;
;;         the retraction) is implemented in the customisation      ;;
;;         module (lego.el or coq.el) which is why this looks so    ;;
;;         straightforward                                          ;;


(defun proof-done-retracting (span)
  "Updates display after proof process has reset its state. See also
the documentation for `proof-retract-until-point'. It optionally
deletes the region corresponding to the proof sequence."
  (let ((start (span-start span))
        (end (span-end span))
	(kill (span-property span 'delete-me)))
    (proof-set-locked-end start)
    (proof-set-queue-end start)
    (delete-spans start end 'type)
    (delete-span span)
    (if kill (delete-region start end))))

(defun proof-setup-retract-action (start end proof-command delete-region)
  (let ((span (make-span start end)))
    (set-span-property span 'delete-me delete-region)
    (list (list span proof-command 'proof-done-retracting))))

(defun proof-retract-target (target delete-region)
  (let ((end (proof-locked-end))
	(start (span-start target))
	(span (proof-last-goal-or-goalsave))
	actions)
    
    (if (and span (not (eq (span-property span 'type) 'goalsave)))
	(if (< (span-end span) (span-end target))
	    (progn
	      (setq span target)
	      (while (and span (eq (span-property span 'type) 'comment))
		(setq span (next-span span 'type)))
	      (setq actions (proof-setup-retract-action
			     start end 
			     (if (null span) "COMMENT"
			       (funcall proof-count-undos-fn span))
			     delete-region)
		    end start))
	  
	  (setq actions (proof-setup-retract-action (span-start span) end
						    proof-kill-goal-command
						    delete-region)
		end (span-start span))))
    
    (if (> end start) 
	(setq actions
	      (nconc actions (proof-setup-retract-action 
			      start end
			      (funcall proof-find-and-forget-fn target)
			      delete-region))))
      
    (proof-start-queue (min start end) (proof-locked-end) actions)))

(defun proof-retract-until-point (&optional delete-region)
  "Sets up the proof process for retracting until point. In
   particular, it sets a flag for the filter process to call
   `proof-done-retracting' after the proof process has actually
   successfully reset its state. It optionally deletes the region in
   the proof script corresponding to the proof command sequence. If
   this function is invoked outside a locked region, the last
   successfully processed command is undone."
  (interactive)
  (proof-check-process-available)
  (let ((span (span-at (point) 'type)))
    (if (null (proof-locked-end)) (error "No locked region"))
    (and (null span)
	 (progn (proof-goto-end-of-locked) (backward-char)
		(setq span (span-at (point) 'type))))
    (proof-retract-target span delete-region)))

;;         proof-try-command                                        ;;
;;         this isn't really in the spirit of script management,    ;;
;;         but sometimes the user wants to just try an expression   ;;
;;         without having to undo it in order to try something      ;;
;;         different. Of course you can easily lose sync by doing   ;;
;;         something here which changes the proof state             ;;

(defun proof-done-trying (span)
  (delete-span span)
  (proof-detach-queue))
			
(defun proof-try-command
  (&optional unclosed-comment-fun) 

  "Process the command at point,
   but don't add it to the locked region. This will only happen if
   the command satisfies proof-state-preserving-p.

   Default action if inside a comment is just to go until the start of
   the comment. If you want something different, put it inside
   unclosed-comment-fun."
  (interactive)
  (let ((pt (point)) semis crowbar test)
    (setq crowbar (proof-steal-process))
    (save-excursion
      (if (not (re-search-backward "\\S-" (proof-locked-end) t))
	  (progn (goto-char pt)
		 (error "Nothing to do!")))
      (setq semis (proof-segment-up-to (point))))
    (if (and unclosed-comment-fun (eq 'unclosed-comment (car semis)))
	(funcall unclosed-comment-fun)
      (if (eq 'unclosed-comment (car semis)) (setq semis (cdr semis)))
      (if (and (not crowbar) (null semis)) (error "Nothing to do!"))
      (setq test (car semis))
      (if (not (funcall proof-state-preserving-p (nth 1 test)))
	  (error "Command is not state preserving"))
      (goto-char (nth 2 test))
      (let ((vanillas (proof-semis-to-vanillas (list test)
					       'proof-done-trying)))
	(if crowbar (setq vanillas (cons crowbar vanillas)))
	(proof-start-queue (proof-locked-end) (point) vanillas)))))


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;         misc other user functions                                ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;


(defun proof-undo-last-successful-command ()
  "Undo last successful command, both in the buffer recording the
   proof script and in the proof process. In particular, it deletes
   the corresponding part of the proof script."
  (interactive)
  (goto-char (span-start (span-at-before (proof-locked-end) 'type)))
  (proof-retract-until-point t))

(defun proof-interrupt-process ()
  (interactive)
  (if (not (proof-shell-live-buffer))
      (error "Proof Process Not Started!"))
  (if (not (eq proof-script-buffer (current-buffer)))
      (error "Don't own process!"))
  (if (not proof-shell-busy)
      (error "Proof Process Not Active!"))
  (save-excursion
    (set-buffer proof-shell-buffer)
    (comint-interrupt-subjob)))
  
    
(defun proof-find-next-terminator ()
  "Set point after next `proof-terminal-char'."
  (interactive)
  (let ((cmd (span-at (point) 'type)))
    (if cmd (goto-char (span-end cmd))
      (and (re-search-forward "\\S-" nil t)
	   (proof-assert-until-point nil 'ignore-proof-process)))))

(defun proof-process-buffer ()
  "Process the current buffer and set point at the end of the buffer."
  (interactive)
  (end-of-buffer)
  (proof-assert-until-point))

;; For when things go horribly wrong

(defun proof-restart-script ()
  (interactive)
  (save-excursion
    (if (buffer-live-p proof-script-buffer)
	(progn
	  (set-buffer proof-script-buffer)
	  (setq proof-active-buffer-fake-minor-mode nil)
	  (delete-spans (point-min) (point-max) 'type)
	  (proof-detach-segments)))
    (setq proof-shell-busy nil
	  proof-script-buffer nil)
    (if (buffer-live-p proof-shell-buffer) 
	(kill-buffer proof-shell-buffer))
    (if (buffer-live-p proof-pbp-buffer)
	(kill-buffer proof-pbp-buffer))))

;; A command for making things go horribly wrong - it moves the
;; end-of-locked-region marker backwards, so user had better move it
;; correctly to sync with the proof state, or things will go all
;; pear-shaped.

(defun proof-frob-locked-end ()
  (interactive)
  "Move the end of the locked region backwards. 
   Only for use by consenting adults."
  (cond
   ((not (eq proof-script-buffer (current-buffer)))
    (error "Not in proof buffer"))
   ((> (point) (proof-locked-end))
    (error "Can only move backwards"))
   (t (proof-set-locked-end (point))
      (delete-spans (proof-locked-end) (point-max) 'type))))

(defvar proof-minibuffer-history nil
  "The last command read from the minibuffer")

(defun proof-execute-minibuffer-cmd ()
  (interactive)
  (let (cmd)
    (proof-check-process-available 'relaxed)
    (setq cmd (read-string "Command: " nil 'proof-minibuffer-history))
    (proof-invisible-command cmd 'relaxed)))
	  

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Popup and Pulldown Menu ;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;; Menu commands for the underlying proof assistant
(defvar proof-ctxt-string ""
  "Command to display context in proof assistant")

(defvar proof-help-string ""
  "Command to ask for help in proof assistant")

(defvar proof-prf-string ""
  "Command to display proof state in proof assistant")

(defun proof-ctxt ()
  "List context."
  (interactive) 
  (proof-invisible-command (concat proof-ctxt-string proof-terminal-string)))

(defun proof-help ()
  "Print help message giving syntax."
  (interactive)
  (proof-invisible-command (concat proof-help-string proof-terminal-string)))

(defun proof-prf ()
  "List proof state."
  (interactive)
  (proof-invisible-command (concat proof-prf-string proof-terminal-string)))

;;; To be called from menu
(defun proof-info-mode ()
  "Info mode on proof mode."
  (interactive)
  (info "script-management"))

(defun proof-exit ()
  "Exit Proof-assistant."
  (interactive)
  (proof-restart-script))

;;; The following was particular to LEGO:
;;;	    ("Help"
;;;	     ["The LEGO Reference Card" (w3-fetch lego-www-refcard) t]
;;;	     ["The LEGO library (WWW)"
;;;	      (w3-fetch lego-library-www-page)  t]
;;;	     ["The LEGO Proof-assistant (WWW)"
;;;	      (w3-fetch lego-www-home-page)  t]
;;;	     ["Help on Emacs LEGO-mode" lego-info-mode  t]
;;;	     ["Customisation" (w3-fetch lego-www-customisation-page)
;;;	      t]
;;;            ))))

(defvar proof-shared-menu
  (append '(
            ["Display context" proof-ctxt
	      :active (proof-shell-live-buffer)]
            ["Display proof state" proof-prf
	      :active (proof-shell-live-buffer)]
	    ["Exit proof assistant" proof-exit
	      :active (proof-shell-live-buffer)]
	    "----"
	    ["Find definition/declaration" find-tag-other-window t]
	    ("Help"
	     ["Proof assistant web page"
	      (w3-fetch proof-www-home-page) t]
	     ["Help on Emacs proof-mode" proof-info-mode t]
	     ))))

(defvar proof-menu  
  (append '("Commands"
            ["Toggle active terminator" proof-active-terminator-minor-mode
	     :active t
	     :style toggle
             :selected proof-active-terminator-minor-mode]
            "----")
          (list (if (string-match "XEmacs 19.1[2-9]" emacs-version)
		    "--:doubleLine" "----"))
          proof-shared-menu
          )
  "*The menu for the proof assistant.")

(defvar proof-shell-menu proof-shared-menu
  "The menu for the Proof-assistant shell")

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;          Active terminator minor mode                            ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(deflocal proof-active-terminator-minor-mode nil 
  "active terminator minor mode flag")

(defun proof-active-terminator-minor-mode (&optional arg)
  "Toggle PROOF's Active Terminator minor mode.
With arg, turn on the Active Terminator minor mode if and only if arg
is positive.

If Active terminator mode is enabled, a terminator will process the
current command."

 (interactive "P")
 
;; has this minor mode been registered as such?
  (or (assq 'proof-active-terminator-minor-mode minor-mode-alist)
      (setq minor-mode-alist
            (append minor-mode-alist
                    (list '(proof-active-terminator-minor-mode
			    (concat " " proof-terminal-string))))))

  (setq proof-active-terminator-minor-mode
        (if (null arg) (not proof-active-terminator-minor-mode)
          (> (prefix-numeric-value arg) 0)))
  (if (fboundp 'redraw-modeline)
      (redraw-modeline)
    (force-mode-line-update)))

(defun proof-process-active-terminator ()
  "Insert the terminator in an intelligent way and assert until the
  new terminator.  Fire up proof process if necessary."
  (let ((mrk (point)) ins)
    (if (looking-at "\\s-\\|\\'\\|\\w") 
	(if (not (re-search-backward "\\S-" (proof-unprocessed-begin) t))
	    (error "Nothing to do!")))
    (if (not (= (char-after (point)) proof-terminal-char))
	(progn (forward-char) (insert proof-terminal-string) (setq ins t)))
    (proof-assert-until-point
     (function (lambda ()
		 (if ins (backward-delete-char 1))
		 (goto-char mrk) (insert proof-terminal-string))))))

(defun proof-active-terminator ()
  (interactive)
  (if proof-active-terminator-minor-mode 
      (proof-process-active-terminator)
    (self-insert-command 1)))


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Proof mode configuration                                         ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;


(define-derived-mode proof-mode fundamental-mode 
  "Proof" "Proof mode - not standalone"
  ;; define-derived-mode proof-mode initialises proof-mode-map
  (setq proof-buffer-type 'script))

;; This has to come after proof-mode is defined

(define-derived-mode proof-shell-mode comint-mode 
  "proof-shell" "Proof shell mode - not standalone"
  (setq proof-buffer-type 'shell)
  (setq proof-shell-busy nil)
  (setq proof-shell-delayed-output (cons 'insert "done"))
  (setq comint-prompt-regexp proof-shell-prompt-pattern)
  (add-hook 'comint-output-filter-functions 'proof-shell-filter nil t)
  (setq comint-get-old-input (function (lambda () "")))
  (proof-dont-show-annotations)
  (setq proof-marker (make-marker)))

(easy-menu-define proof-shell-menu
		  proof-shell-mode-map
		  "Menu used in the proof assistant shell."
		  (cons "Proof" (cdr proof-shell-menu)))

(easy-menu-define proof-mode-menu  
		  proof-mode-map
		  "Menu used in proof mode."
		  (cons "Proof" (cdr proof-menu)))

;; the following callback is an irritating hack - there should be some
;; elegant mechanism for computing constants after the child has
;; configured.

(defun proof-config-done () 

;; calculate some strings and regexps for searching

  (setq proof-terminal-string (char-to-string proof-terminal-char))

  (setq pbp-goal-command (concat "Pbp %s" proof-terminal-string))
  (setq pbp-hyp-command (concat "PbpHyp %s" proof-terminal-string))

  (make-local-variable 'comment-start)
  (setq comment-start (concat proof-comment-start " "))
  (make-local-variable 'comment-end)
  (setq comment-end (concat " " proof-comment-end))
  (make-local-variable 'comment-start-skip)
  (setq comment-start-skip 
    (concat (regexp-quote proof-comment-start) "+\\s_?"))

  (setq proof-re-end-of-cmd (concat "\\s_*" proof-terminal-string "\\s_*\\\'"))
  (setq proof-re-term-or-comment 
	(concat proof-terminal-string "\\|" (regexp-quote proof-comment-start)
		"\\|" (regexp-quote proof-comment-end)))

;; func-menu --- Jump to a goal within a buffer
  (and (boundp 'fume-function-name-regexp-alist)
       (defvar fume-function-name-regexp-proof
	 (cons proof-goal-with-hole-regexp 2))
       (push (cons major-mode 'fume-function-name-regexp-proof)
	     fume-function-name-regexp-alist))
  (and (boundp 'fume-find-function-name-method-alist)
       (push (cons major-mode 'fume-match-find-next-function-name)
	     fume-find-function-name-method-alist))

;; Info
  (or (memq proof-info-dir Info-default-directory-list)
      (setq Info-default-directory-list
	    (cons proof-info-dir Info-default-directory-list)))

;; keymaps and menus
  (easy-menu-add proof-mode-menu proof-mode-map)

  (proof-define-keys proof-mode-map proof-universal-keys)

  (define-key proof-mode-map
    (vconcat [(control c)] (vector proof-terminal-char))
    'proof-active-terminator-minor-mode)

  (define-key proof-mode-map [(control c) (control e)]
    'proof-find-next-terminator)

  (define-key proof-mode-map (vector proof-terminal-char)
    'proof-active-terminator)
  (define-key proof-mode-map [(control c) (return)] 'proof-assert-until-point)
  (define-key proof-mode-map [(control c) (control t)] 'proof-try-command)
  (define-key proof-mode-map [(control c) ?u] 'proof-retract-until-point)
  (define-key proof-mode-map [(control c) (control u)]
    'proof-undo-last-successful-command)

  (define-key proof-mode-map [(control c) ?\']
    'proof-goto-end-of-locked-interactive)
  (define-key proof-mode-map [(control button1)] 'proof-send-span)
  (define-key proof-mode-map [(control c) (control b)] 'proof-process-buffer)
  (define-key proof-mode-map [(control c) (control z)] 'proof-frob-locked-end)

  (define-key proof-mode-map [tab]      'proof-indent-line)
  (setq indent-line-function 'proof-indent-line)

  (define-key (current-local-map) [(control c) (control p)] 'proof-prf)
  (define-key (current-local-map) [(control c) ?c] 'proof-ctxt)
  (define-key (current-local-map) [(control c) ?h] 'proof-help)

;; For fontlock
  (remove-hook 'font-lock-after-fontify-buffer-hook 'proof-zap-commas-buffer t)
  (add-hook 'font-lock-after-fontify-buffer-hook 'proof-zap-commas-buffer nil t)
  (remove-hook 'font-lock-mode-hook 'proof-unfontify-separator t)
  (add-hook 'font-lock-mode-hook 'proof-unfontify-separator nil t)

;; if we don't have the following, zap-commas fails to work.

  (and (boundp 'font-lock-always-fontify-immediately)
       (setq font-lock-always-fontify-immediately t)))

(defun proof-shell-config-done ()
  (accept-process-output (get-buffer-process (current-buffer)))

  ;; If the proof process in invoked on a different machine e.g.,
  ;; for proof-prog-name="rsh fastmachine proofprocess", one needs
  ;; to adjust the directory:
  (and proof-shell-cd
       (proof-shell-insert (format proof-shell-cd
       ;; under Emacs 19.34 default-directory contains "~" which causes
       ;; problems with LEGO's internal Cd command
				   (expand-file-name default-directory))))

  (if proof-shell-init-cmd
       (proof-shell-insert proof-shell-init-cmd))

;; Note that proof-marker actually gets set in proof-shell-filter.
;; This is manifestly a hack, but finding somewhere more convenient
;; to do the setup is tricky.

  (while (null (marker-position proof-marker))
    (if (accept-process-output (get-buffer-process (current-buffer)) 15)
	()
      (error "Failed to initialise proof process")))

  (run-hooks 'proof-mode-hook))

(define-derived-mode pbp-mode fundamental-mode 
  "Proof" "Proof by Pointing"
  ;; defined-derived-mode pbp-mode initialises pbp-mode-map
  (setq proof-buffer-type 'pbp)
  (suppress-keymap pbp-mode-map 'all)
;  (define-key pbp-mode-map [(button2)] 'pbp-button-action)
  (proof-define-keys pbp-mode-map proof-universal-keys)
  (erase-buffer))


(provide 'proof)