;; proof-config.el  Proof General configuration for proof assistant
;;
;; Copyright (C) 1994 - 1998 LFCS Edinburgh. 
;; Authors: David Aspinall, Yves Bertot, Healfdene Goguen,
;;          Thomas Kleymann and Dilip Sequeira
;;
;; Maintainer:  Proof General maintainer <proofgen@dcs.ed.ac.uk>
;;
;; $Id$
;;
;; This file declares all user options and prover-specific
;; configuration variables for Proof General.  The variables
;; are used variously by the proof script mode and the 
;; proof shell mode, menus, and toolbar.
;; 
;; To customize Proof General for a new proof assistant, you
;; should read this file carefully! 
;;
;;  1. User options 
;;  2. Major modes
;;  3. Menus, user-level commands.
;;  4. Script mode configuration 
;;  5. Shell mode configuration
;;     5a. commands
;;     5b. regexps
;;     5c. hooks
;;  6. Goals buffer configuration
;;  7. Splash screen settings
;;  8. Global constants 
;;
;; The user options don't need to be set on a per-prover basis,
;; and the global constants probably should not be touched.
;; The remaining variables in sections 2-5 should be set for
;; each proof assistant.  You don't need to set every variable
;; for basic functionality; consult the manual for details of
;; which ones are important.
;;
;; Customization groups and structure
;;
;;  proof-general	: User options for Proof General    (1)
;;    <Prover name>     : User options for proof assistant
;;
;;  proof-general-internals  :  Internal settings of Proof General (6)
;;    prover-config	     :  Configuration for proof assistant (2,3)
;;      proof-script	     :     settings for proof script mode (4)
;;      proof-shell	     :     settings for proof shell mode (5)
;;    <Prover name>-config   :  Specific internal settings for a prover
;;
;; ==================================================
;;
;; Developers notes:
;;   1. When adding a new configuration variable, please
;;       (a) put it in the right customize group, and
;;       (b) add a magical comment in NewDoc.texi to document it!
;;   2. Presently the customize library seems a bit picky over the
;;    	:type property and some correct types don't work properly.
;;    	If the type is ill-formed, editing the whole group will be broken.
;;    	Check after updates, by killing all customize buffers and
;;    	invoking customize-group
;;
;; ==================================================


;;
;; 1. User options for proof mode
;;
;; The following variables are user options for Proof General.
;; They appear in the 'proof' customize group and should
;; *not* normally be touched by prover specific code.
;;

(defcustom proof-prog-name-ask nil
  "*If non-nil, query user which program to run for the inferior process."
  :type 'boolean
  :group 'proof-general)

(defcustom proof-prog-name-guess nil
  "*If non-nil, use `proof-guess-command-line' to guess proof-prog-name.
This option is compatible with proof-prog-name-ask.
No effect if proof-guess-command-line is nil."
  :type 'boolean
  :group 'proof-general)

(defcustom proof-toolbar-inhibit nil
  "*Non-nil prevents toolbar being used for script buffers.
NB: the toolbar is only available with XEmacs."
  :type 'boolean
  :group 'proof-general)

(defcustom proof-toolbar-follow-mode 'locked
  "*Choice of how point moves with toolbar commands.
One of the symbols: 'locked, 'follow, 'ignore.
If 'locked, point sticks to the end of the locked region with toolbar commands.
If 'follow, point moves just when needed to display the locked region end.
If 'ignore, point is never moved after toolbar movement commands."
  :type '(choice
	  (const :tag "Follow locked region" locked)
	  (const :tag "Keep locked region displayed" follow)
	  (const :tag "Never move" ignore))
  :group 'proof-general)

(defcustom proof-window-dedicated nil
  "*Whether response and goals buffers have dedicated windows.
If t, windows displaying responses from the prover will not
be switchable to display other windows.  This may help manage
your display, but can sometimes be inconvenient, especially
for experienced Emacs users.
Moreover, this option may cause problems with multi-frame
use because of a bug."
  :type 'boolean
  :group 'proof-general)

(defcustom proof-strict-read-only 
  ;; For FSF Emacs, strict read only is buggy when used in
  ;; conjunction with font-lock.

  ;; The second conjunctive ensures that the expression is either
  ;; `nil' or `strict' (and not 15).  
  (and (string-match "XEmacs" emacs-version) 'strict)
  "*Whether Proof General is strict about the read-only region in buffers.
If non-nil, an error is given when an attempt is made to edit the
read-only region.  If nil, Proof General is more relaxed (but may give
you a reprimand!)

The default value for proof-strict-read-only depends on which
version of Emacs you are using.  In FSF Emacs, strict read only is buggy
when it used in conjunction with font-lock, so it is disabled by default."
  :type 'boolean
  :group 'proof-general)

(defcustom proof-auto-retract
  nil
  ;; Not implemented yet, only an idea.
  "*If non-nil, retract automatically when locked region is edited.
With this option active, the locked region will automatically be
unlocked when the user attempts to edit it.   To make use of this
option, proof-strict-read-only should be turned off.

Note: this feature has not been implemented yet."
  :type 'boolean
  :group 'proof-general)

(defcustom proof-script-indent nil
  ;; Particular proof assistants can enable this if they feel
  ;; confident about it.  (I don't). -da
  "*If non-nil, enable indentation code for proof scripts.
Currently the indentation code can be rather slow for large scripts,
and is critical on the setting of regular expressions for particular
provers.  Enable it if it works for you."  
  :type 'boolean 
  :group 'proof-general)

(defcustom proof-one-command-per-line nil
  "*If non-nil, format for newlines after each proof command in a script.
This option is not fully-functional at the moment."
  :type 'boolean
  :group 'proof-general)

(defcustom proof-rsh-command ""
  "*Shell command prefix to run a command on a remote host.  
For example,

   ssh bigjobs

Would cause Proof General to issue the command `ssh bigjobs isabelle'
to start Isabelle remotely on our large compute server called `bigjobs'.

The protocol used should be configured so that no user interaction
(passwords, or whatever) is required to get going."
  :type 'string
  :group 'proof-general)

(defcustom proof-auto-delete-windows nil
  "*If non-nil, automatically remove windows when they are cleaned.
For example, at the end of a proof the goals buffer window will
be cleared; if this flag is set it will automatically be removed.
If you want to fix the sizes of your windows you may want to set this
variable to 'nil' to avoid windows being deleted automatically.
If you use multiple frames, only the windows in the currently
selected frame will be automatically deleted."
  :type 'boolean
  :group 'proof-general)

(defcustom proof-splash-inhibit
  nil
  "*Non-nil prevents splash screen display when Proof General is loaded."
  :type 'boolean
  :group 'proof-general)



;;
;; Faces.
;; We ought to test that these work sensibly:
;;   a) with default colours
;;   b) with -rv
;;   c) on console 
;;   d) on win32
;;   e) all above with FSF Emacs and XEmacs.
;; But it's difficult to keep track of all that!  
;; Please report any bad/failing colour 
;; combinations to proofgen@dcs.ed.ac.uk
;;
;; Some of these faces aren't used by default in Proof General,
;; but you can use them in font lock patterns for specific
;; script languages.
;;

(defgroup proof-faces nil
  "Faces used by Proof General."
  :group 'proof
  :prefix "proof-")
  

(defface proof-queue-face
  '((((type x) (class color) (background light))
     (:background "mistyrose"))
    (((type x) (class color) (background dark))
     (:background "mediumvioletred"))
    (t				
     (:foreground "white" :background "black")))
  "*Face for commands in proof script waiting to be processed."
  :group 'proof-faces)

(defface proof-locked-face
  '((((type x) (class color) (background light))   
     (:background "lavender"))
    (((type x) (class color) (background dark))   
     (:background "navy"))
    (t				
     (:underline t)))
  "*Face for locked region of proof script (processed commands)."
  :group 'proof-faces)

(defface proof-declaration-name-face
  '((((type x) (class color) (background light))   
     (:foreground "chocolate" 
      :bold t))
    (((type x) (class color) (background dark))   
     (:foreground "orange"
      :bold t))
    (t				
     (:italic t :bold t)))
  "*Face for declaration names in proof scripts.
Exactly what uses this face depends on the proof assistant."
  :group 'proof-faces)

(defconst proof-declaration-name-face 'proof-declaration-name-face
  "Expression that evaluates to a face.
Required so that 'proof-declaration-name-face is a proper facename in
both XEmacs 20.4 and Emacs 20.2's version of font-lock.")

(defface proof-tacticals-name-face
  '((((type x) (class color) (background light))   
     (:foreground "MediumOrchid3"))
    (((type x) (class color) (background dark))   
     (:foreground "orchid"))
    (t				
     (bold t)))
  "*Face for names of tacticals in proof scripts.
Exactly what uses this face depends on the proof assistant."
  :group 'proof-faces)

(defconst proof-tacticals-name-face 'proof-tacticals-name-face
  "Expression that evaluates to a face.
Required so that 'proof-tacticals-name-face is a proper facename in
both XEmacs 20.4 and Emacs 20.3's version of font-lock.")

(defface proof-tactics-name-face
  '((t				
     (bold t)))
  "*Face for names of tactics in proof scripts.
By default, they are printed with default face but the user
may want to color them differently."
  :group 'proof-faces)

(defconst proof-tactics-name-face 'proof-tactics-name-face
  "Expression that evaluates to a face.
Required so that 'proof-tactics-name-face is a proper facename in
both XEmacs 20.4 and Emacs 20.3's version of font-lock.")

(defface proof-error-face 
  '((((type x) (class color) (background light))   
     (:background "salmon1"  
      :bold t))
    (((type x) (class color) (background dark))   
     (:background "brown" 
      :bold t))
    (t				
     (:bold t)))
  "*Face for error messages from proof assistant."
  :group 'proof-faces)

(defface proof-warning-face
  '((((type x) (class color) (background light))   
     (:background "lemon chiffon"))
    (((type x) (class color) (background dark))   
     (:background "orange2"))
    (t				
     (:italic t)))
  "*Face for warning messages.
Warning messages can come from proof assistant or from Proof General itself."
  :group 'proof-faces)

(defface proof-eager-annotation-face
  '((((type x) (class color) (background light))   
     (:background "lightgoldenrod"))
    (((type x) (class color) (background dark))   
     (:background "darkgoldenrod"))
    (t				
     (:italic t)))
  "*Face for messages from proof assistant."
  :group 'proof-faces)





;;
;; CONFIGURATION VARIABLES
;;
;;

(defgroup prover-config nil
  "Configuration of Proof General for the prover in use."
  :group 'proof-general-internals
  :prefix "proof-")

;; The variables in the "prover-config" (NB: not "proof config"!!)
;; customize group are those which are intended to be set by the
;; prover specific elisp, i.e. constants set on a per-prover basis.

;; Putting these in a customize group is useful for documenting
;; this type of variable, and for developing a new instantiation
;; of Proof General.
;; But it is *not* useful for final user-level customization!
;; The reason is that saving these customizations across a session is
;; not liable to work, because the prover specific elisp usually
;; overrides with a series of setq's in <assistant>-mode-config type
;; functions.  This is why prover-config appears under the
;; proof-general-internal group.


(defcustom proof-assistant ""
  "Name of the proof assistant Proof General is using.
Do not change this variable! It is set automatically by the mode 
stub defined in proof-site, from the name given in 
proof-assistant-table."
  :type 'string
  :group 'prover-config)

;; 18.12.98: Added this variable, useful for future simplified
;;           mechanisms of instantiation.
(defcustom proof-assistant-symbol nil
  "Symbol name of the proof assistant Proof General is using.
Used for automatic configuration based on standard variable names.
Settings will be found by looking for names beginning with this
symbol as a prefix.
Do not change this variable! It is set automatically by the mode 
stub defined in proof-site, from the symbols given in 
proof-assistant-table."
  :type 'sexp
  :group 'prover-config)




;;
;; 2. The major modes used by Proof General.
;;

;; FIXME: these functions could be set automatically to standard values,
;; i.e. <assistant>-mode, <assistant>-shell-mode, <assistant>-pbp-mode.
;; FIXME: mode-for-script is unused at the moment, added just for
;; uniformity.  The other two are used when a shell buffer is started.
;; FIXME da: old suggestion for the later three was to use 
;; pre-shell-start-hook.  I don't really understand why that hook
;; is necessary, it just makes things more complicated.

(defcustom proof-mode-for-shell 'proof-shell-mode
  "Mode for proof shell buffers.
Usually customised for specific prover.
Suggestion: this can be set in the shell mode configuration."
  :type 'function
  :group 'prover-config)

(defcustom proof-mode-for-response 'proof-response-mode
  "Mode for proof response buffer.
Usually customised for specific prover.
Suggestion: this can be set in the shell mode configuration."
  :type 'function
  :group 'prover-config)

;; FIXME: ought to be renamed to proof-mode-for-goals
(defcustom proof-mode-for-pbp 'pbp-mode
  "Mode for proof state display buffers.
Usually customised for specific prover.
Suggestion: this can be set in the shell mode configuration."
  :type 'function
  :group 'prover-config)

(defcustom proof-mode-for-script 'proof-mode
  "Mode for proof script buffers.
This is used by Proof General to find out which buffers 
contain proof scripts.
Suggestion: this can be set in the script mode configuration."
  :type 'function
  :group 'prover-config)

(defcustom proof-guess-command-line nil
  "Function to guess command line for proof assistant, given a filename.
The function could take a filename as argument, run `make -n' to see
how to compile the file non-interactively, then translate the result 
into an interactive invocation of the proof assistant with the same 
command line options.  For an example, see coq/coq.el."
  :type 'function
  :group 'prover-config)



;;
;; 3. Configuration for menus, user-level commands, etc.
;;

(defcustom proof-assistant-home-page ""
  "Web address for information on proof assistant"
  :type 'string
  :group 'prover-config)

(defcustom proof-ctxt-string ""
  "Command to display the context in proof assistant."
  :type 'string
  :group 'prover-config)

(defcustom proof-help-string ""
  "Command to ask for help in proof assistant."
  :type 'string
  :group 'prover-config)

(defcustom proof-prf-string ""
  "Command to display proof state in proof assistant."
  :type 'string
  :group 'prover-config)

(defcustom proof-goal-command nil
  "Command to set a goal in the proof assistant.  String or fn.
If a string, the format character `%s' will be replaced by the
goal string. If a function, should return a command string to
insert when called interactively."
  :type '(choice string function)
  :group 'prover-config)

(defcustom proof-save-command nil
  "Command to save a proved theorem in the proof assistant.  String or fn.
If a string, the format character `%s' will be replaced by the
theorem name. If a function, should return a command string to
insert when called interactively."
  :type '(choice string function)
  :group 'prover-config)



;;
;; 4. Configuration for proof script mode
;;

;;
;; The following variables should be set before proof-config-done
;; is called.  These configure the mode for the script buffer,
;; including highlighting, etc.
;;

(defgroup proof-script nil
  "Proof General configuration of scripting buffer mode."
  :group 'prover-config
  :prefix "proof-")


(defcustom proof-terminal-char nil
  "Character which terminates a command in a script buffer."
  :type 'character
  :group 'proof-script)

(defcustom proof-comment-start ""
  "String which starts a comment in the proof assistant command language.
The script buffer's comment-start is set to this string plus a space."
  :type 'string
  :group 'proof-script)

(defcustom proof-comment-end ""
  "String which ends a comment in the proof assistant command language.
The script buffer's comment-end is set to this string plus a space."
  :type 'string
  :group 'proof-script)

(defcustom proof-string-start-regexp "\""
  "Matches the start of a quoted string in the proof assistant command language."
  :type 'string
  :group 'proof-script)

(defcustom proof-string-end-regexp "\""
  "Matches the end of a quoted string in the proof assistant command language."
  :type 'string
  :group 'proof-script)

(defcustom proof-case-fold-search nil
  "Value for case-fold-search when recognizing portions of proof scripts.
The default value is 'nil'.  If your prover has a case *insensitive*
input syntax, proof-case-fold-search should be set to 't' instead.  
NB: This setting is not used for matching output from the prover."  
  :type 'boolean :group
  'proof-script)

(defcustom proof-save-command-regexp nil 
  "Matches a save command"
  :type 'regexp
  :group 'proof-script)

(defcustom proof-save-with-hole-regexp nil 
  "Regexp which matches a command to save a named theorem.
Match number 2 should be the name of the theorem saved.
Used for setting names of goal..save regions and for default
func-menu configuration in proof-script-find-next-goalsave."
  :type 'regexp
  :group 'proof-script)

(defcustom proof-goal-command-regexp nil
  "Matches a goal command."
  :type 'regexp
  :group 'proof-script)

(defcustom proof-goal-with-hole-regexp nil 
  "Regexp which matches a command used to issue and name a goal.
Match number 2 should be the name of the goal issued.
Used for setting names of goal..save regions and for default
func-menu configuration in proof-script-find-next-goalsave."
  :type 'regexp
  :group 'proof-script)

(defcustom proof-script-next-entity-regexps nil
  "Regular expressions to help find definitions and proofs in a script.
This is the list of the form

   (ANYENTITY-REGEXP
    DISCRIMINATOR-REGEXP  ... DISCRIMINATOR-REGEXP)

The idea is that ANYENTITY-REGEXP matches any named entity in the
proof script, on a line where the name appears.  This is assumed to be
the start or the end of the entity.  The discriminators then test
which kind of entity has been found, to get its name.  A
DISCRIMINATOR-REGEXP has one of the forms

  (REGEXP MATCHNO) 
  (REGEXP MATCHNO 'backward BACKREGEXP) 
  (REGEXP MATCHNO 'forward FORWARDREGEXP)

If REGEXP matches the string captured by ANYENTITY-REGEXP, then
MATCHNO is the match number for the substring which names the entity.

If 'backward BACKREGEXP is present, then the start of the entity
is found by searching backwards for BACKREGEXP.

Conversely, if 'forward FORWARDREGEXP is found, then the end of
the entity is found by searching forwards for FORWARDREGEXP.

Otherwise, the start and end of the entity will be the region matched
by ANYENTITY-REGEXP.

This mechanism allows fairly complex parsing of the buffer, in
particular, it allows for goal..save regions which are named
only at the end.  However, it does not parse strings,
comments, or parentheses.

This variable may not need to be set: a default value which should
work for goal..saves is calculated from proof-goal-with-hole-regexp,
proof-goal-command-regexp, and proof-save-with-hole-regexp."
  :type 'sexp
    ;; Bit tricky.
    ;; (list (regexp :tag "Any entity matcher")
    ;;    (:inline t repeat (choice regexp (const 'backward) etc
  :group 'proof-script)


(defcustom proof-script-find-next-entity-fn
  'proof-script-find-next-entity
  "Name of function to find next interesting entity in a script buffer.
This is used to configure func-menu.  The default value is
proof-script-find-next-entity, which searches for the next entity
based on fume-function-name-regexp which by default is set from
proof-script-next-entity-regexps.  The function should move
point forward in a buffer, and return a cons cell of the name and the
beginning of the entity's region."
  :type 'function
  :group 'proof-script)

;; FIXME da: This next one is horrible.  We clearly would rather
;; have proof-goal-regexp instead.  This was born to solve
;; problem that Coq can have goals which look like definitions, etc.
;; Perhaps we can generalise the matching to understand function
;; values as well as regexps. 

(defcustom proof-goal-command-p nil 
  "Is this really a goal command?"
  :type 'function
  :group 'proof-script)

;; FIXME mmw: increasing the horror even more ...

(defcustom proof-really-save-command-p (lambda (span cmd) t)
  "Is this really a save command?"
  :type 'function
  :group 'proof-script)

(defcustom proof-lift-global nil
  "This function lifts local lemmas from inside goals out to top level.
This function takes the local goalsave span as an argument. Set this
to `nil' of the proof assistant does not support nested goals."
  :type 'function
  ;; FIXME customize broken on choices with function in them?
  ;; :type '(choice (const :tag "No local lemmas" nil) (function))
  :group 'proof-script)

(defcustom proof-count-undos-fn nil 
  "Compute number of undos in a target segment"
  :type 'function
  :group 'proof-script)

; Not yet implemented.
;
;(defcustom proof-atomic-sequence-lists nil
;  "list of instructions for setting up atomic sequences of commands (ACS).

;Each instruction is
;a list of the form `(END START &optional FORGET-COMMAND)'. END is a
;regular expression to recognise the last command in an ACS. START
;is a function. Its input is the last command of an ACS. Its output
;is a regular exression to recognise the first command of the ACS.
;It is evaluated once and the output is successively matched agains
;previously processed commands until a match occurs (or the
;beginning of the current buffer is reached). The region determined
;by (START,END) is locked as an ACS. Optionally, the ACS is
;annotated with the actual command to retract the ACS. This is
;computed by applying FORGET-COMMAND to the first and last command
;of the ACS."
;  ;; FIXME customize broken on choices with function in them?
;  ;;:type '(repeat (cons regexp function (choice (const nil) function)))
;  :type '(repeat (cons regexp function function))
;  :group 'proof-shell)


(defconst proof-no-command "COMMENT"
  "String used as a nullary action (send no command to the proof assistant).
Only relevant for proof-find-and-forget-fn.")

(defcustom proof-find-and-forget-fn nil
  "Function returning a command string to forget back to before its argument span.
The special string proof-no-command means there is nothing to do."
  :type 'function
  :group 'proof-script)

(defcustom proof-goal-hyp-fn nil
  "Function which returns cons cell if point is at a goal/hypothesis.
First element of cell is a symbol, 'goal' or 'hyp'.  The second
element is a string: the goal or hypothesis itself.  This is used
when parsing the proofstate output."
  :type 'function
  :group 'proof-script)

(defcustom proof-kill-goal-command ""
  "Command to kill a goal."
  :type 'string
  :group 'proof-script)

(defcustom proof-global-p nil
  "Whether a command is a global declaration.  Predicate on strings or nil.
This is used to handle nested goals allowed by some provers."
  :type 'function
  :group 'proof-script)

(defcustom proof-state-preserving-p nil
  "A predicate, non-nil if its argument (a command) preserves the proof state."
  :type 'function
  :group 'proof-script)

(defcustom proof-activate-scripting-hook nil
  "Hook run when a buffer is switched into scripting mode.
The current buffer will be the newly active scripting buffer.

This hook may be useful for synchronizing with the proof
assistant, for example, to switch to a new theory."
  :type '(repeat function)
  :group 'proof-script)

;;
;; Proof script indentation
;; FIXME: document this stuff
;;

(defcustom proof-stack-to-indent nil
  "Prover-specific code for indentation."
  :type 'sexp
  :group 'proof-script)

(defcustom proof-parse-indent nil
  "Proof-assistant specific function for parsing.
Invoked in `proof-parse-to-point'. Must be a
function taking two arguments, a character (the current character)
and a stack reflecting indentation, and must return a stack. The
stack is a list of the form (c . p) where `c' is a character
representing the type of indentation and `p' records the column for
indentation. The generic `proof-parse-to-point' function supports
parentheses and commands. It represents these with the characters
`?\(', `?\[' and `proof-terminal-char'. "
  :type 'sexp
  :group 'proof-script)







;;
;;  5. Configuration for proof shell	                            
;;
;; The variables in this section concern the proof shell mode.
;; The first group of variables are hooks invoked at various points.
;; The second group of variables are concerned with matching the output
;; from the proof assistant.
;;
;; Variables here are put into the customize group 'proof-shell'.
;;
;; These should be set in the shell mode configuration, again,
;; before proof-shell-config-done is called.
;;

(defgroup proof-shell nil
  "Settings for output from the proof assistant in the proof shell."
  :group 'prover-config
  :prefix "proof-shell-")


;; 
;; 5a. commands
;;

(defcustom proof-prog-name nil
  "System command to run program name in proof shell.
Suggestion: this can be set in proof-pre-shell-start-hook from
a variable which is in the proof assistant's customization
group.  This allows different proof assistants to coexist
(albeit in separate Emacs sessions)."
  :type 'string
  :group 'proof-shell)

(defcustom proof-shell-init-cmd ""
   "The command for initially configuring the proof process."
   :type '(choice string (const nil))
   :group 'proof-shell)

(defcustom proof-shell-restart-cmd ""
   "A command for re-initialising the proof process."
   :type '(choice string (const nil))
   :group 'proof-shell)

(defcustom proof-shell-quit-cmd nil
  "A command to quit the proof process.  If nil, send EOF instead."
   :type '(choice string (const nil))
   :group 'proof-shell)

(defcustom proof-shell-cd nil
  "Command to the proof assistant to change the working directory."
  :type 'string
  :group 'proof-shell)


;;
;; 5b. Regexp variables for matching output from proof process.
;;

(defcustom proof-shell-prompt-pattern nil 
   "Proof shell's value for comint-prompt-pattern."
   :type 'regexp
   :group 'proof-shell)

;; FIXME da: replace this with wakeup-regexp or prompt-regexp?
;; May not need next variable.
(defcustom proof-shell-wakeup-char nil
  "A special character which terminates an annotated prompt.
Set to nil if proof assistant does not support annotated prompts."
  :type '(choice character (const nil))
  :group 'proof-shell)

(defcustom proof-shell-first-special-char nil
  "First special character.
Codes above this character can have special meaning to Proof General,
and are stripped from the prover's output strings."
  :type '(choice character (const nil))
  :group 'proof-shell)

(defcustom proof-shell-annotated-prompt-regexp ""
  "Regexp matching a (possibly annotated) prompt pattern.
Output is grabbed between pairs of lines matching this regexp.
To help matching you may be able to annotate the proof assistant
prompt with a special character not appearing in ordinary output.
The special character should appear in this regexp, and should
be the value of proof-shell-wakeup-char."
  :type 'regexp
  :group 'proof-shell)

(defcustom proof-shell-abort-goal-regexp nil
  "Regexp matching output from an aborted proof."
  :type 'regexp
  :group 'proof-shell)

(defcustom proof-shell-error-regexp nil
  "Regexp matching an error report from the proof assistant.

We assume that an error message corresponds to a failure in the last
proof command executed.  So don't match mere warning messages with
this regexp.  Moreover, an error message should not be matched as an
eager annotation (see proof-shell-eager-annotation-start) otherwise it
will be lost.

The engine matches interrupts before errors, see proof-shell-interupt-regexp.

It is safe to leave this variable unset nil."
  :type '(choice nil regexp)
  :group 'proof-shell) 

(defcustom proof-shell-interrupt-regexp nil
  "Regexp matching output indicating the assistant was interrupted.
We assume that an interrupt message corresponds to a failure
in the last proof command executed. So don't match
mere warning messages with this regexp.
Moreover, an interrupt message should not be matched as
an eager annotation (see proof-shell-eager-annotation-start)
otherwise it will be lost.
The engine matches interrupts before errors."
  :type 'regexp
  :group 'proof-shell) 

(defcustom proof-shell-proof-completed-regexp nil
  "Regexp matching output indicating a finished proof."
  :type 'regexp
  :group 'proof-shell)

(defcustom proof-shell-clear-response-regexp nil
  "Regexp matching output telling Proof General to clear the response buffer.
This feature is useful to give the prover more control over what output
is shown to the user.  Set to nil to disable."
  :type 'regexp
  :group 'proof-shell)

(defcustom proof-shell-clear-goals-regexp nil
  "Regexp matching output telling Proof General to clear the goals buffer.
This feature is useful to give the prover more control over what output
is shown to the user.  Set to nil to disable."
  :type 'regexp
  :group 'proof-shell)

(defcustom proof-shell-start-goals-regexp ""
  "Regexp matching the start of the proof state output."
  :type 'regexp
  :group 'proof-shell)

(defcustom proof-shell-end-goals-regexp ""
  "Regexp matching the end of the proof state output."
  :type 'regexp
  :group 'proof-shell)

(defcustom proof-shell-eager-annotation-start nil
  "Eager annotation field start.  A regular expression or nil.
An eager annotation indicates to Emacs that some following output
should be displayed immediately and not accumulated for parsing.
Set to nil to disable this feature."
  :type '(choice regexp (const :tag "Disabled" nil))
  :group 'proof-shell)

(defcustom proof-shell-eager-annotation-end "\n"
  "Eager annotation field end.  A regular expression or nil.
An eager annotation indicates to Emacs that some following output
should be displayed immediately and not accumulated for parsing.

The default value is \"\\n\" to match up to the end of the line."
  :type '(choice regexp (const :tag "Unset" nil))
  :group 'proof-shell)

(defcustom proof-shell-assumption-regexp nil
  "A regular expression matching the name of assumptions."
  :type '(choice regexp (const :tag "Unset" nil))
  :group 'proof-shell)

(defcustom proof-shell-process-file nil
  "A pair (REGEXP . FUNCTION) to match a processed file name.

If REGEXP matches output, then the function FUNCTION is invoked on the
output string chunk. It must return a script file name (with complete
path) the system is currently processing. In practice, FUNCTION is
likely to inspect the match data.  If it returns the empty string,
the file name of the scripting buffer is used instead.  If it
returns nil, no action is taken.

Care has to be taken in case the prover only reports on compiled
versions of files it is processing. In this case, FUNCTION needs to
reconstruct the corresponding script file name. The new (true) file
name is added to the front of `proof-included-files-list'."
  :type '(choice (cons regexp function) (const nil))
  :group 'proof-shell)


;; FIXME da: why not amalgamate the next two into a single
;;	     variable as above?

(defcustom proof-shell-retract-files-regexp nil
  "A REGEXP to match that the prover has retracted across file boundaries.

At this stage, Proof General's view of the processed files is out of
date and needs to be updated with the help of the function
`proof-shell-compute-new-files-list'."
  :type '(choice regexp (const nil))
  :group 'proof-shell)

(defcustom proof-shell-compute-new-files-list nil
  "Function to update `proof-included-files list'.

It needs to return an up to date list of all processed files. Its
output is stored in `proof-included-files-list'. Its input is the
string of which `proof-shell-retract-files-regexp' matched a
substring. In practice, this function is likely to inspect the
previous (global) variable `proof-included-files-list' and the match
data triggered by `proof-shell-retract-files-regexp'."
  :type '(choice function (const nil))
  :group 'proof-shell)



;;
;; 5c. hooks and hook-related variables
;;

(defcustom proof-shell-insert-hook nil 
  "Hooks run by proof-shell-insert before inserting a command.
Can be used to configure the proof assistant to the interface in
various ways -- for example, to observe or alter the commands sent to
the prover, or to sneak in extra commands to configure the 
prover (LEGO uses this to set the pretty printer's line width if 
the window width has changed).

This hook is called inside a save-excursion with the proof-shell-buffer 
current, just before inserting and sending the text in the 
variable STRING.  The hook can massage STRING or insert additional 
text directly into the proof-shell-buffer.  
Before sending STRING, it will be stripped of carriage returns.

NB: You should be very careful about setting this hook.  Proof General
relies on a careful synchronization with the process between inputs
and outputs.  It expects to see a prompt for each input it sends from
the queue.  If you add extra input here and it causes more prompts
than expected, things will break!  Massaging the STRING variable
may be safer since it is stripped of carriage returns 
before being sent."
  :type '(repeat function)
  :group 'proof-shell)

(defcustom proof-pre-shell-start-hook nil
  "Hooks run before proof shell is started.
This may be set to a function which configures the proof shell
variables."
  :type '(repeat function)
  :group 'proof-shell)

(defcustom proof-shell-handle-delayed-output-hook
  '(proof-pbp-focus-on-first-goal)
  "Hooks run after new output has been displayed in the response buffer."
  :type '(repeat function)
  :group 'proof-shell)

(defcustom proof-shell-handle-error-hook
  '(proof-goto-end-of-locked-if-pos-not-visible-in-window)
  "Hooks run after an error has been reported in the response buffer."
  :type '(repeat function)
  :group 'proof-shell)

(defcustom proof-shell-process-output-system-specific nil
  "Set this variable to handle system specific output.
Errors, start of proofs, abortions of proofs and completions of
proofs are recognised in the function `proof-shell-process-output'.
All other output from the proof engine is simply reported to the
user in the RESPONSE buffer.

To catch further special cases, set this variable to a pair of
functions '(condf . actf). Both are given (cmd string) as arguments.
`cmd' is a string containing the currently processed command.
`string' is the response from the proof system. To change the
behaviour of `proof-shell-process-output', (condf cmd string) must
return a non-nil value. Then (actf cmd string) is invoked. See the
documentation of `proof-shell-process-output' for the required
output format."
  :type '(cons (function function))
  :group 'proof-shell)

(defcustom proof-state-change-hook nil
  "This hook is called when state change may have occurred. 
Specifically, this hook is called after a region has been
asserted or retracted, or after a command has been sent
to the prover with proof-shell-invisible-command.

This hook is used within Proof General to refresh the 
toolbar.")



;;
;; 6. Goals buffer
;;

(defgroup proof-goals nil
  "Settings for configuring the goals buffer."
  :group 'prover-config
  :prefix "pbp-")

(defcustom pbp-change-goal nil
  "Command to change to the goal `%s'"
  :type 'string
  :group 'proof-goals)

(defcustom pbp-goal-command nil
  "Command informing the prover that `pbp-button-action' has been
requested on a goal."
  :type 'regexp
  :group 'proof-goals)

(defcustom pbp-hyp-command nil
  "Command informing the prover that `pbp-button-action' has been
requested on an assumption."
  :type 'regexp
  :group 'proof-goals)

(defcustom pbp-error-regexp nil
  "Regexp indicating that the proof process has identified an error."
  :type 'regexp
  :group 'proof-goals)

(defcustom proof-shell-result-start ""
  "Regexp matching start of an output from the prover after pbp commands.
In particular, after a `pbp-goal-command' or a `pbp-hyp-command'."
  :type 'regexp
  :group 'proof-goals)

(defcustom proof-shell-result-end ""
  "Regexp matching end of output from the prover after pbp commands.
In particular, after a `pbp-goal-command' or a `pbp-hyp-command'."
  :type 'regexp
  :group 'proof-goals)

(defcustom proof-shell-start-char nil
  "Starting special for a subterm markup.
Subsequent characters with values *below* proof-shell-first-special-char
are assumed to be subterm position indicators.  Subterm markups should
be finished with proof-shell-end-char."
  :type '(choice character (const nil))
  :group 'proof-goals)

(defcustom proof-shell-end-char nil
  "Finishing special for a subterm markup.
See documentation of proof-shell-start-char."
  :type '(choice character (const nil))
  :group 'proof-goals)

(defcustom proof-shell-goal-char nil
  "goal mark"
  :type 'character
  :group 'proof-goals)

(defcustom proof-shell-field-char nil
  "annotated field end"
  :type 'character
  :group 'proof-goals)

(defcustom proof-shell-start-char nil
  "Starting special for a subterm markup.
Subsequent characters with values *below* proof-shell-first-special-char
are assumed to be subterm position indicators.  Subterm markups should
be finished with proof-shell-end-char."
  :type '(choice character (const nil))
  :group 'proof-goals)

(defcustom proof-shell-end-char nil
  "Finishing special for a subterm markup.
See documentation of proof-shell-start-char."
  :type '(choice character (const nil))
  :group 'proof-goals)

(defcustom proof-shell-goal-char nil
  "goal mark"
  :type '(choice character (const nil))
  :group 'proof-goals)

(defcustom proof-shell-field-char nil
  "annotated field end"
  :type '(choice character (const nil))
  :group 'proof-goals)



;;
;; 7. Splash screen settings
;;

(defcustom proof-splash-time 1.5
  "Minimum number of seconds to display splash screen for.
The splash screen may be displayed for a couple of seconds longer than
this, depending on how long it takes the machine to initialise 
Proof General."
  :type 'number
  :group 'proof-general-internals)

(defcustom proof-splash-contents
  '(list
    nil
    nil
;;; Remove the text for now: XEmacs makes a mess of displaying the
;;; transparent parts of the gif (at least, on all machines I have seen)
;;;    (proof-splash-display-image "pg-text" t)
    nil
    (proof-splash-display-image "ProofGeneral")
    nil
    "Welcome to"
    (concat proof-assistant " Proof General!")
    nil)
  "Evaluated to configure splash screen displayed when entering Proof General.
If an element is a string or an image specifier, it is displayed
centred on the window on its own line.  If it is nil, a new line is
inserted."
  :type 'sexp
  :group 'proof-general-internals)

(defcustom proof-splash-extensions nil
  "Prover specific extensions of splash screen.
These are evaluated and appended to `proof-splash-contents'."
  :type 'sexp
  :group 'proof-config)
  






;;
;; 8. Global constants
;; 
(defcustom proof-general-name "Proof-General"
  "Proof General name used internally and in menu titles."
  :type 'string
  :group 'proof-general-internals)

(defcustom proof-proof-general-home-page
  "http://www.dcs.ed.ac.uk/home/proofgen"
  "*Web address for Proof General"
  :type 'string
  :group 'proof-general-internals)

;; FIXME: da: could we put these into another keymap shared across the
;; various PG modes?
(defcustom proof-universal-keys
  '(([(control c) (control c)] . proof-interrupt-process)
    ([(control c) (control v)] . proof-execute-minibuffer-cmd))
"List of keybindings made for the script, goals and response buffer. 
Elements of the list are tuples `(k . f)' 
where `k' is a keybinding (vector) and `f' the designated function."
  :type 'sexp
  :group 'proof-general-internals)



;; End of proof-config.el
(provide 'proof-config)