;; coq-compile-common.el --- common part of compilation feature
;; Copyright (C) 1994-2012 LFCS Edinburgh.
;; Authors: Hendrik Tews
;; License:     GPL (GNU GENERAL PUBLIC LICENSE)
;; Maintainer: Hendrik Tews <hendrik@askra.de>
;;
;; $Id$
;;
;;; Commentary:
;;
;; This file holds constants, options and some general functions for
;; the compilation feature.
;;


(require 'proof-shell)
(require 'coq-system)

(eval-when (compile)
  ;;(defvar coq-pre-v85 nil)
  (defvar coq-confirm-external-compilation nil); defpacustom
  (defvar coq-compile-parallel-in-background nil) ; defpacustom
  (proof-ready-for-assistant 'coq))     ; compile for coq


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; Multiple file handling -- sequential compilation of required modules
;;

;;; enable / disable parallel / sequential compilation
;; I would rather put these functions into coq-seq-compile and
;; coq-par-compile, respectively. However, the :initialization
;; function of a defcustom seems to be evaluated when reading the
;; defcustom form. Therefore, these functions must be defined already,
;; when the defpacustum coq-compile-parallel-in-background is read.

(defun coq-par-enable ()
  "Enable parallel compilation.
Must be used together with `coq-seq-disable'."
  (add-hook 'proof-shell-extend-queue-hook
	    'coq-par-preprocess-require-commands)
  (add-hook 'proof-shell-signal-interrupt-hook
	    'coq-par-emergency-cleanup)
  (add-hook 'proof-shell-handle-error-or-interrupt-hook
	    'coq-par-emergency-cleanup))

(defun coq-par-disable ()
  "Disable parallel compilation.
Must be used together with `coq-seq-enable'."
  (remove-hook 'proof-shell-extend-queue-hook
	       'coq-par-preprocess-require-commands)
  (remove-hook 'proof-shell-signal-interrupt-hook
	       'coq-par-emergency-cleanup)
  (remove-hook 'proof-shell-handle-error-or-interrupt-hook
	       'coq-par-emergency-cleanup))

(defun coq-seq-enable ()
  "Enable sequential synchronous compilation.
Must be used together with `coq-par-disable'."
  (add-hook 'proof-shell-extend-queue-hook
	    'coq-seq-preprocess-require-commands))

(defun coq-seq-disable ()
  "Disable sequential synchronous compilation.
Must be used together with `coq-par-enable'."
  (remove-hook 'proof-shell-extend-queue-hook
	       'coq-seq-preprocess-require-commands))



(defun coq-switch-compilation-method ()
  "Set function for coq-compile-parallel-in-background."
  (if coq-compile-parallel-in-background
      (progn
	(coq-par-enable)
	(coq-seq-disable))
    (coq-par-disable)
    (coq-seq-enable)))

(defun number-of-cpus ()
  (let (status ncpus)
    (condition-case nil
	(with-temp-buffer
	  (setq status
		(call-process "getconf" nil (current-buffer) t 
			      "_NPROCESSORS_ONLN"))
	  (setq ncpus (string-to-number (buffer-string))))
      (error
       (setq status -1)))
    (if (and (eq status 0) (> ncpus 0))
	ncpus
      nil)))

(defvar coq-internal-max-jobs 1
  "Value of `coq-max-background-compilation-jobs' translated to a number.")

(defun coq-max-jobs-setter (symbol new-value)
  ":set function for `coq-max-background-compilation-jobs.
SYMBOL should be 'coq-max-background-compilation-jobs"
  (set symbol new-value)
  (cond
   ((eq new-value 'all-cpus)
    (setq new-value (number-of-cpus))
    (unless new-value
      (setq new-value 1)))
   ((and (integerp new-value) (> new-value 0)) t)
   (t (setq new-value 1)))
  (setq coq-internal-max-jobs new-value))


;;; user options and variables

(defgroup coq-auto-compile ()
  "Customization for automatic compilation of required files"
  :group 'coq
  :package-version '(ProofGeneral . "4.1"))

(defpacustom compile-before-require nil
  "If non-nil, check dependencies of required modules and compile if necessary.
If non-nil ProofGeneral intercepts \"Require\" commands and checks if the
required library module and its dependencies are up-to-date. If not, they
are compiled from the sources before the \"Require\" command is processed.

This option can be set/reset via menu
`Coq -> Settings -> Compile Before Require'."
  :type 'boolean
  :safe 'booleanp
  :group 'coq-auto-compile)

(defpacustom compile-parallel-in-background nil
  "Choose the internal compilation method.
When Proof General compiles itself, you have the choice between
two implementations. If this setting is nil, then Proof General
uses the old implementation and compiles everything sequentially
with synchronous job. With this old method Proof General is
locked during compilation. If this setting is t, then the new
method is used and compilation jobs are dispatched in parallel in
the background. The maximal number of parallel compilation jobs
is set with `coq-max-background-compilation-jobs'.

This option can be set/reset via menu
`Coq -> Settings -> Compile Parallel In Background'."
  :type 'boolean
  :safe 'booleanp
  :group 'coq-auto-compile
  :eval (coq-switch-compilation-method))

;; defpacustom fails to call :eval during inititialization, see trac #456
(coq-switch-compilation-method)

(defcustom coq-max-background-compilation-jobs 'all-cpus
  "Maximal number of parallel jobs, if parallel compilation is enabled.
Use the number of available CPU cores if this is set to
'all-cpus. This variable is the user setting. The value that is
really used is `coq-internal-max-jobs'. Use `coq-max-jobs-setter'
or the customization system to change this variable. Otherwise
your change will have no effect, because `coq-internal-max-jobs'
is not adapted."
  :type '(choice (const :tag "use all CPU cores" all-cpus)
		 (integer :tag "fixed number" :value 1))
  :safe (lambda (v) (or (eq v 'all-cpus) (and (integerp v) (> v 0))))
  :set 'coq-max-jobs-setter
  :group 'coq-auto-compile)

(defcustom coq-compile-command ""
  "External compilation command. If empty ProofGeneral compiles itself.
If unset (the empty string) ProofGeneral computes the dependencies of
required modules with coqdep and compiles as necessary. This internal
dependency checking does currently not handle ML modules.

If a non-empty string, the denoted command is called to do the
dependency checking and compilation. Before executing this
command the following keys are substituted as follows:
  %p  the (physical) directory containing the source of
      the required module
  %o  the Coq object file in the physical directory that will
      be loaded
  %s  the Coq source file in the physical directory whose
      object will be loaded
  %q  the qualified id of the \"Require\" command
  %r  the source file containing the \"Require\"

For instance, \"make -C %p %o\" expands to \"make -C bar foo.vo\"
when module \"foo\" from directory \"bar\" is required.

After the substitution the command can be changed in the
minibuffer if `coq-confirm-external-compilation' is t."
  :type 'string
  :safe (lambda (v)
          (and (stringp v)
               (or (not (boundp 'coq-confirm-external-compilation))
                   coq-confirm-external-compilation)))
  :group 'coq-auto-compile)

(defconst coq-compile-substitution-list
  '(("%p" physical-dir)
    ("%o" module-object)
    ("%s" module-source)
    ("%q" qualified-id)
    ("%r" requiring-file))
  "Substitutions for `coq-compile-command'.
Value must be a list of substitutions, where each substitution is
a 2-element list. The first element of a substitution is the
regexp to substitute, the second the replacement. The replacement
is evaluated before passing it to `replace-regexp-in-string', so
it might be a string, or one of the symbols 'physical-dir,
'module-object, 'module-source, 'qualified-id and
'requiring-file, which are bound to, respectively, the physical
directory containing the source file, the Coq object file in
'physical-dir that will be loaded, the Coq source file in
'physical-dir whose object will be loaded, the qualified module
identifier that occurs in the \"Require\" command, and the file
that contains the \"Require\".")


(defcustom coq-compile-auto-save 'ask-coq
  "Buffers to save before checking dependencies for compilation.
There are two orthogonal choices: Firstly one can save all or only the coq
buffers, where coq buffers means all buffers in coq mode except the current
buffer. Secondly, Emacs can ask about each such buffer or save all of them
unconditionally.

This makes four permitted values: 'ask-coq to confirm saving all
modified Coq buffers, 'ask-all to confirm saving all modified
buffers, 'save-coq to save all modified Coq buffers without
confirmation and 'save-all to save all modified buffers without
confirmation."
  :type
  '(radio
    (const :tag "ask for each coq-mode buffer, except the current buffer"
           ask-coq)
    (const :tag "ask for all buffers" ask-all)
    (const
     :tag
     "save all coq-mode buffers except the current buffer without confirmation"
     save-coq)
    (const :tag "save all buffers without confirmation" save-all))
  :safe (lambda (v) (member v '(ask-coq ask-all save-coq save-all)))
  :group 'coq-auto-compile)

(defcustom coq-lock-ancestors t
  "If non-nil, lock ancestor module files.
If external compilation is used (via `coq-compile-command') then
only the direct ancestors are locked. Otherwise all ancestors are
locked when the \"Require\" command is processed."
  :type 'boolean
  :safe 'booleanp
  :group 'coq-auto-compile)

(defpacustom confirm-external-compilation t
  "If set let user change and confirm the compilation command.
Otherwise start the external compilation without confirmation.

This option can be set/reset via menu
`Coq -> Settings -> Confirm External Compilation'."
  :type 'boolean
  :group 'coq-auto-compile)


(defcustom coq-compile-ignored-directories nil
  "Directories in which ProofGeneral should not compile modules.
List of regular expressions for directories in which ProofGeneral
should not compile modules. If a library file name matches one
of the regular expressions in this list then ProofGeneral does
neither compile this file nor check its dependencies for
compilation. It makes sense to include non-standard coq library
directories here if they are not changed and if they are so big
that dependency checking takes noticeable time."
  :type '(repeat regexp)
  :safe (lambda (v) (every 'stringp v))
  :group 'coq-auto-compile)

(defcustom coq-compile-ignore-library-directory t
  "If non-nil, ProofGeneral does not compile modules from the coq library.
Should be `t' for normal coq users. If `nil' library modules are
compiled if their sources are newer.

This option has currently no effect, because Proof General uses
coqdep to translate qualified identifiers into library file names
and coqdep does not output dependencies in the standard library."
  :type 'boolean
  :safe 'booleanp
  :group 'coq-auto-compile)

(defcustom coq-coqdep-error-regexp
  (concat "^\\*\\*\\* Warning: in file .*, library .* is required "
          "and has not been found")
  "Regexp to match errors in the output of coqdep.
coqdep indicates errors not always via a non-zero exit status,
but sometimes only via printing warnings. This regular expression
is used for recognizing error conditions in the output of
coqdep (when coqdep terminates with exit status 0). Its default
value matches the warning that some required library cannot be
found on the load path and ignores the warning for finding a
library at multiple places in the load path. If you want to turn
the latter condition into an error, then set this variable to
\"^\\*\\*\\* Warning\"."
  :type 'string
  :safe 'stringp
  :group 'coq-auto-compile)


(defconst coq-require-id-regexp
  "[ \t\n]*\\([A-Za-z0-9_']+\\(\\.[A-Za-z0-9_']+\\)*\\)[ \t\n]*"
  "Regular expression matching one Coq module identifier.
Should match precisely one complete module identifier and surrounding
white space. The module identifier must be matched with group number 1.
Note that the trailing dot in \"Require A.\" is not part of the module
identifier and should therefore not be matched by this regexp.")

(defconst coq-require-command-regexp
  "\\(?:^From[ \t\n]+\\(?1:[A-Za-z0-9_']+\\(?:\\.[A-Za-z0-9_']+\\)*\\)[ \t\n]*\\)?\\(?2:Require[ \t\n]+\\(?:Import\\|Export\\)?\\)[ \t\n]*"
  "Regular expression matching Require commands in Coq.
Should match \"Require\" with its import and export variants up to (but not
including) the first character of the first required module. The required
modules are matched separately with `coq-require-id-regexp'")

(defvar coq-compile-history nil
  "History of external Coq compilation commands.")

(defvar coq-compile-response-buffer "*coq-compile-response*"
  "Name of the buffer to display error messages from coqc and coqdep.")


(defvar coq-debug-auto-compilation nil
  "*Display more messages during compilation")


;;; basic utilities

(defun time-less-or-equal (time-1 time-2)
  "Return `t' if time value time-1 is earlier or equal to time-2.
A time value is a list of two integers as returned by `file-attributes'.
The first integer contains the upper 16 bits and the second the lower
16 bits of the time."
  (or (time-less-p time-1 time-2)
      (equal time-1 time-2)))

(defun coq-max-dep-mod-time (dep-mod-times)
  "Return the maximum in DEP-MOD-TIMES.
Argument DEP-MOD-TIMES is a list where each element is either a
time value (see `time-less-or-equal') or 'just-compiled. The
function returns the maximum of the elements in DEP-MOD-TIMES,
where 'just-compiled is considered the greatest time value. If
DEP-MOD-TIMES is empty it returns nil."
  (let ((max nil))
    (while dep-mod-times
      (cond
       ((eq (car dep-mod-times) 'just-compiled)
        (setq max 'just-compiled
              dep-mod-times nil))
       ((eq max nil)
        (setq max (car dep-mod-times)))
       ((time-less-p max (car dep-mod-times))
        (setq max (car dep-mod-times))))
      (setq dep-mod-times (cdr-safe dep-mod-times)))
    max))


;;; Compute command line for starting coqtop





;;; ignore library files

(defun coq-compile-ignore-file (lib-obj-file)
  "Check whether ProofGeneral should handle compilation of LIB-OBJ-FILE.
Return `t' if ProofGeneral should skip LIB-OBJ-FILE and `nil' if
ProofGeneral should handle the file. For normal users it does, for instance,
not make sense to let ProofGeneral check if the coq standard library
is up-to-date."
  (or
   (and
    coq-compile-ignore-library-directory
    (eq (compare-strings coq-library-directory 0 nil
                         lib-obj-file 0 (length coq-library-directory))
        t)
    (if coq-debug-auto-compilation
        (message "Ignore lib file %s" lib-obj-file))
    t)
   (if (some
          (lambda (dir-regexp) (string-match dir-regexp lib-obj-file))
          coq-compile-ignored-directories)
       (progn
         (if coq-debug-auto-compilation
             (message "Ignore %s" lib-obj-file))
         t)
     nil)))

;;; convert .vo files to .v files

(defun coq-library-src-of-obj-file (lib-obj-file)
  "Return source file name for LIB-OBJ-FILE.
Chops off the last character of LIB-OBJ-FILE to convert \"x.vo\" to \"x.v\"."
  (substring lib-obj-file 0 (- (length lib-obj-file) 1)))


;;; ancestor unlocking
;;; (locking is different for sequential and parallel compilation)

(defun coq-unlock-ancestor (ancestor-src)
  "Unlock ANCESTOR-SRC."
  (let* ((true-ancestor (file-truename ancestor-src)))
    (setq proof-included-files-list
          (delete true-ancestor proof-included-files-list))
    (proof-restart-buffers (proof-files-to-buffers (list true-ancestor)))))

(defun coq-unlock-all-ancestors-of-span (span)
  "Unlock all ancestors that have been locked when SPAN was asserted."
  (mapc 'coq-unlock-ancestor (span-property span 'coq-locked-ancestors))
  (span-set-property span 'coq-locked-ancestors ()))


;;; manage coq-compile-respose-buffer

(defun coq-init-compile-response-buffer (command)
  "Initialize the buffer for the compilation output.
If `coq-compile-response-buffer' exists, empty it. Otherwise
create a buffer with name `coq-compile-response-buffer', put
it into `compilation-mode' and store it in
`coq-compile-response-buffer' for later use. Argument COMMAND is
the command whose output will appear in the buffer."
  (let ((buffer-object (get-buffer coq-compile-response-buffer)))
    (if buffer-object
        (let ((inhibit-read-only t))
          (with-current-buffer buffer-object
            (erase-buffer)))
      (setq buffer-object
            (get-buffer-create coq-compile-response-buffer))
      (with-current-buffer buffer-object
        (compilation-mode)
	;; read-only-mode makes compilation fail if some messages need
	;; to be displayed by compilation. there was a bug in emacs 23
	;; which make it work some time without this, but now it seems
	;; mandatory:
	(read-only-mode 0)))
    ;; I don't really care if somebody gets the right mode when
    ;; he saves and reloads this buffer. However, error messages in
    ;; the first line are not found for some reason ...
    (let ((inhibit-read-only t))
      (with-current-buffer buffer-object
        (insert "-*- mode: compilation; -*-\n\n" command "\n")))))

(defun coq-display-compile-response-buffer ()
  "Display the errors in `coq-compile-response-buffer'."
  (with-current-buffer coq-compile-response-buffer
    ;; fontification enables the error messages
    (let ((font-lock-verbose nil)) ; shut up font-lock messages
      (font-lock-fontify-buffer)))
  ;; Make it so the next C-x ` will use this buffer.
  (setq next-error-last-buffer (get-buffer coq-compile-response-buffer))
  (proof-display-and-keep-buffer coq-compile-response-buffer 1 t))


;;; save some buffers

(defvar coq-compile-buffer-with-current-require
  "Local variable for two coq-seq-* functions.
This only locally used variable communicates the current buffer
from `coq-compile-save-some-buffers' to
`coq-compile-save-buffer-filter'.")

(defun coq-compile-save-buffer-filter ()
  "Filter predicate for `coq-compile-save-some-buffers'.
See also `save-some-buffers'. Returns t for buffers with major
mode 'coq-mode' different from
`coq-compile-buffer-with-current-require' and nil for all other
buffers. The buffer to test must be current."
  (and
   (eq major-mode 'coq-mode)
   (not (eq coq-compile-buffer-with-current-require
            (current-buffer)))))
  
(defun coq-compile-save-some-buffers ()
  "Save buffers according to `coq-compile-auto-save'.
Uses the local variable coq-compile-buffer-with-current-require to pass the
current buffer (which contains the Require command) to
`coq-compile-save-buffer-filter'."
  (let ((coq-compile-buffer-with-current-require (current-buffer))
        unconditionally buffer-filter)
    (cond
     ((eq coq-compile-auto-save 'ask-coq)
      (setq unconditionally nil
            buffer-filter 'coq-compile-save-buffer-filter))
     ((eq coq-compile-auto-save 'ask-all)
      (setq unconditionally nil
            buffer-filter nil))
     ((eq coq-compile-auto-save 'save-coq)
      (setq unconditionally t
            buffer-filter 'coq-compile-save-buffer-filter))
     ((eq coq-compile-auto-save 'save-all)
      (setq unconditionally t
            buffer-filter nil)))
    (save-some-buffers unconditionally buffer-filter)))


;;; kill coqtop on script buffer change

(defun coq-switch-buffer-kill-proof-shell ()
  "Kill the proof shell without asking the user.
This function is for `proof-deactivate-scripting-hook'. It kills
the proof shell without asking the user for
confirmation (assuming she agreed already on switching the active
scripting buffer). This is needed to ensure the load path is
correct in the new scripting buffer."
  (unless proof-shell-exit-in-progress
    (proof-shell-exit t)))

;; This is now always done (in coq.el)
;(add-hook 'proof-deactivate-scripting-hook
;          'coq-switch-buffer-kill-proof-shell
;          t)


(provide 'coq-compile-common)

;;   Local Variables: ***
;;   coding: utf-8 ***
;;   End: ***

;;; coq-compile-common.el ends here
