Use define-minor-mode in CEDET where applicable.

[bpt/emacs.git] / lisp / cedet / semantic / idle.el

;;; idle.el --- Schedule parsing tasks in idle time

;; Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009, 2010
;;   Free Software Foundation, Inc.

;; Author: Eric M. Ludlam <zappo@gnu.org>
;; Keywords: syntax

;; This file is part of GNU Emacs.

;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:
;;
;; Originally, `semantic-auto-parse-mode' handled refreshing the
;; tags in a buffer in idle time.  Other activities can be scheduled
;; in idle time, all of which require up-to-date tag tables.
;; Having a specialized idle time scheduler that first refreshes
;; the tags buffer, and then enables other idle time tasks reduces
;; the amount of work needed.  Any specialized idle tasks need not
;; ask for a fresh tags list.
;;
;; NOTE ON SEMANTIC_ANALYZE
;;
;; Some of the idle modes use the semantic analyzer.  The analyzer
;; automatically caches the created context, so it is shared amongst
;; all idle modes that will need it.

(require 'semantic)
(require 'semantic/ctxt)
(require 'semantic/format)
(require 'semantic/tag)
(require 'timer)

;; For the semantic-find-tags-by-name macro.
(eval-when-compile (require 'semantic/find))

(defvar eldoc-last-message)
(declare-function eldoc-message "eldoc")
(declare-function semantic-analyze-interesting-tag "semantic/analyze")
(declare-function semantic-complete-analyze-inline-idle "semantic/complete")
(declare-function semanticdb-deep-find-tags-by-name "semantic/db-find")
(declare-function semanticdb-save-all-db-idle "semantic/db")
(declare-function semanticdb-typecache-refresh-for-buffer "semantic/db-typecache")
(declare-function semantic-decorate-flush-pending-decorations
                  "semantic/decorate/mode")
(declare-function pulse-momentary-highlight-region "pulse")
(declare-function pulse-momentary-highlight-overlay "pulse")
(declare-function semantic-symref-hits-in-region "semantic/symref/filter")

;;; Code:

;;; TIMER RELATED FUNCTIONS
;;
(defvar semantic-idle-scheduler-timer nil
  "Timer used to schedule tasks in idle time.")

(defvar semantic-idle-scheduler-work-timer nil
  "Timer used to schedule tasks in idle time that may take a while.")

(defcustom semantic-idle-scheduler-verbose-flag nil
  "Non-nil means that the idle scheduler should provide debug messages.
Use this setting to debug idle activities."
  :group 'semantic
  :type 'boolean)

(defcustom semantic-idle-scheduler-idle-time 1
  "Time in seconds of idle before scheduling events.
This time should be short enough to ensure that idle-scheduler will be
run as soon as Emacs is idle."
  :group 'semantic
  :type 'number
  :set (lambda (sym val)
         (set-default sym val)
         (when (timerp semantic-idle-scheduler-timer)
           (cancel-timer semantic-idle-scheduler-timer)
           (setq semantic-idle-scheduler-timer nil)
           (semantic-idle-scheduler-setup-timers))))

(defcustom semantic-idle-scheduler-work-idle-time 60
  "Time in seconds of idle before scheduling big work.
This time should be long enough that once any big work is started, it is
unlikely the user would be ready to type again right away."
  :group 'semantic
  :type 'number
  :set (lambda (sym val)
         (set-default sym val)
         (when (timerp semantic-idle-scheduler-timer)
           (cancel-timer semantic-idle-scheduler-timer)
           (setq semantic-idle-scheduler-timer nil)
           (semantic-idle-scheduler-setup-timers))))

(defun semantic-idle-scheduler-setup-timers ()
  "Lazy initialization of the auto parse idle timer."
  ;; REFRESH THIS FUNCTION for XEMACS FOIBLES
  (or (timerp semantic-idle-scheduler-timer)
      (setq semantic-idle-scheduler-timer
            (run-with-idle-timer
             semantic-idle-scheduler-idle-time t
             #'semantic-idle-scheduler-function)))
  (or (timerp semantic-idle-scheduler-work-timer)
      (setq semantic-idle-scheduler-work-timer
            (run-with-idle-timer
             semantic-idle-scheduler-work-idle-time t
             #'semantic-idle-scheduler-work-function)))
  )

(defun semantic-idle-scheduler-kill-timer ()
  "Kill the auto parse idle timer."
  (if (timerp semantic-idle-scheduler-timer)
      (cancel-timer semantic-idle-scheduler-timer))
  (setq semantic-idle-scheduler-timer nil))

\f
;;; MINOR MODE
;;
;; The minor mode portion of this code just sets up the minor mode
;; which does the initial scheduling of the idle timers.
;;

(defcustom semantic-idle-scheduler-mode-hook nil
  "Hook run at the end of the function `semantic-idle-scheduler-mode'."
  :group 'semantic
  :type 'hook)

(defvar semantic-idle-scheduler-mode nil
  "Non-nil if idle-scheduler minor mode is enabled.
Use the command `semantic-idle-scheduler-mode' to change this variable.")
(make-variable-buffer-local 'semantic-idle-scheduler-mode)

(defcustom semantic-idle-scheduler-max-buffer-size 0
  "*Maximum size in bytes of buffers where idle-scheduler is enabled.
If this value is less than or equal to 0, idle-scheduler is enabled in
all buffers regardless of their size."
  :group 'semantic
  :type 'number)

(defsubst semantic-idle-scheduler-enabled-p ()
  "Return non-nil if idle-scheduler is enabled for this buffer.
idle-scheduler is disabled when debugging or if the buffer size
exceeds the `semantic-idle-scheduler-max-buffer-size' threshold."
  (and semantic-idle-scheduler-mode
       (not (and (boundp 'semantic-debug-enabled)
                 semantic-debug-enabled))
       (not semantic-lex-debug)
       (or (<= semantic-idle-scheduler-max-buffer-size 0)
           (< (buffer-size) semantic-idle-scheduler-max-buffer-size))))

;;;###autoload
(define-minor-mode semantic-idle-scheduler-mode
  "Minor mode to auto parse buffer following a change.
When this mode is off, a buffer is only rescanned for tokens when
some command requests the list of available tokens.  When idle-scheduler
is enabled, Emacs periodically checks to see if the buffer is out of
date, and reparses while the user is idle (not typing.)

With prefix argument ARG, turn on if positive, otherwise off.  The
minor mode can be turned on only if semantic feature is available and
the current buffer was set up for parsing.  Return non-nil if the
minor mode is enabled."
  nil nil nil
  (if semantic-idle-scheduler-mode
      (if (not (and (featurep 'semantic) (semantic-active-p)))
          (progn
            ;; Disable minor mode if semantic stuff not available
            (setq semantic-idle-scheduler-mode nil)
            (error "Buffer %s was not set up idle time scheduling"
                   (buffer-name)))
        (semantic-idle-scheduler-setup-timers)))
  (semantic-mode-line-update))

(semantic-add-minor-mode 'semantic-idle-scheduler-mode
                         "ARP")
\f
;;; SERVICES services
;;
;; These are services for managing idle services.
;;
(defvar semantic-idle-scheduler-queue nil
  "List of functions to execute during idle time.
These functions will be called in the current buffer after that
buffer has had its tags made up to date.  These functions
will not be called if there are errors parsing the
current buffer.")

(defun semantic-idle-scheduler-add (function)
  "Schedule FUNCTION to occur during idle time."
  (add-to-list 'semantic-idle-scheduler-queue function))

(defun semantic-idle-scheduler-remove (function)
  "Unschedule FUNCTION to occur during idle time."
  (setq semantic-idle-scheduler-queue
        (delete function semantic-idle-scheduler-queue)))

;;; IDLE Function
;;
(defun semantic-idle-core-handler ()
  "Core idle function that handles reparsing.
And also manages services that depend on tag values."
  (when semantic-idle-scheduler-verbose-flag
    (message "IDLE: Core handler..."))
  (semantic-exit-on-input 'idle-timer
    (let* ((inhibit-quit nil)
           (buffers (delq (current-buffer)
                          (delq nil
                                (mapcar #'(lambda (b)
                                            (and (buffer-file-name b)
                                                 b))
                                        (buffer-list)))))
           safe ;; This safe is not used, but could be.
           others
           mode)
      (when (semantic-idle-scheduler-enabled-p)
        (save-excursion
          ;; First, reparse the current buffer.
          (setq mode major-mode
                safe (semantic-safe "Idle Parse Error: %S"
                       ;(error "Goofy error 1")
                       (semantic-idle-scheduler-refresh-tags)
                       )
                )
          ;; Now loop over other buffers with same major mode, trying to
          ;; update them as well.  Stop on keypress.
          (dolist (b buffers)
            (semantic-throw-on-input 'parsing-mode-buffers)
            (with-current-buffer b
              (if (eq major-mode mode)
                  (and (semantic-idle-scheduler-enabled-p)
                       (semantic-safe "Idle Parse Error: %S"
                         ;(error "Goofy error")
                         (semantic-idle-scheduler-refresh-tags)))
                (push (current-buffer) others))))
          (setq buffers others))
        ;; If re-parse of current buffer completed, evaluate all other
        ;; services.  Stop on keypress.

        ;; NOTE ON COMMENTED SAFE HERE
        ;; We used to not execute the services if the buffer wsa
        ;; unparseable.  We now assume that they are lexically
        ;; safe to do, because we have marked the buffer unparseable
        ;; if there was a problem.
        ;;(when safe
        (dolist (service semantic-idle-scheduler-queue)
          (save-excursion
            (semantic-throw-on-input 'idle-queue)
            (when semantic-idle-scheduler-verbose-flag
              (message "IDLE: execture service %s..." service))
            (semantic-safe (format "Idle Service Error %s: %%S" service)
              (funcall service))
            (when semantic-idle-scheduler-verbose-flag
              (message "IDLE: execture service %s...done" service))
            )))
        ;;)
      ;; Finally loop over remaining buffers, trying to update them as
      ;; well.  Stop on keypress.
      (save-excursion
        (dolist (b buffers)
          (semantic-throw-on-input 'parsing-other-buffers)
          (with-current-buffer b
            (and (semantic-idle-scheduler-enabled-p)
                 (semantic-idle-scheduler-refresh-tags)))))
      ))
  (when semantic-idle-scheduler-verbose-flag
    (message "IDLE: Core handler...done")))

(defun semantic-debug-idle-function ()
  "Run the Semantic idle function with debugging turned on."
  (interactive)
  (let ((debug-on-error t))
    (semantic-idle-core-handler)
    ))

(defun semantic-idle-scheduler-function ()
  "Function run when after `semantic-idle-scheduler-idle-time'.
This function will reparse the current buffer, and if successful,
call additional functions registered with the timer calls."
  (when (zerop (recursion-depth))
    (let ((debug-on-error nil))
      (save-match-data (semantic-idle-core-handler))
      )))

\f
;;; WORK FUNCTION
;;
;; Unlike the shorter timer, the WORK timer will kick of tasks that
;; may take a long time to complete.
(defcustom semantic-idle-work-parse-neighboring-files-flag t
  "*Non-nil means to parse files in the same dir as the current buffer.
Disable to prevent lots of excessive parsing in idle time."
  :group 'semantic
  :type 'boolean)


(defun semantic-idle-work-for-one-buffer (buffer)
  "Do long-processing work for BUFFER.
Uses `semantic-safe' and returns the output.
Returns t if all processing succeeded."
  (with-current-buffer buffer
    (not (and
          ;; Just in case
          (semantic-safe "Idle Work Parse Error: %S"
            (semantic-idle-scheduler-refresh-tags)
            t)

          ;; Force all our include files to get read in so we
          ;; are ready to provide good smart completion and idle
          ;; summary information
          (semantic-safe "Idle Work Including Error: %S"
            ;; Get the include related path.
            (when (and (featurep 'semantic/db) (semanticdb-minor-mode-p))
              (require 'semantic/db-find)
              (semanticdb-find-translate-path buffer nil)
              )
            t)

          ;; Pre-build the typecaches as needed.
          (semantic-safe "Idle Work Typecaching Error: %S"
            (when (featurep 'semantic/db-typecache)
              (semanticdb-typecache-refresh-for-buffer buffer))
            t)
          ))
    ))

(defun semantic-idle-work-core-handler ()
  "Core handler for idle work processing of long running tasks.
Visits Semantic controlled buffers, and makes sure all needed
include files have been parsed, and that the typecache is up to date.
Uses `semantic-idle-work-for-on-buffer' to do the work."
  (let ((errbuf nil)
        (interrupted
         (semantic-exit-on-input 'idle-work-timer
           (let* ((inhibit-quit nil)
                  (cb (current-buffer))
                  (buffers (delq (current-buffer)
                                 (delq nil
                                       (mapcar #'(lambda (b)
                                                   (and (buffer-file-name b)
                                                        b))
                                               (buffer-list)))))
                  safe errbuf)
             ;; First, handle long tasks in the current buffer.
             (when (semantic-idle-scheduler-enabled-p)
               (save-excursion
                 (setq safe (semantic-idle-work-for-one-buffer (current-buffer))
                       )))
             (when (not safe) (push (current-buffer) errbuf))

             ;; Now loop over other buffers with same major mode, trying to
             ;; update them as well.  Stop on keypress.
             (dolist (b buffers)
               (semantic-throw-on-input 'parsing-mode-buffers)
               (with-current-buffer b
                 (when (semantic-idle-scheduler-enabled-p)
                   (and (semantic-idle-scheduler-enabled-p)
                        (unless (semantic-idle-work-for-one-buffer (current-buffer))
                          (push (current-buffer) errbuf)))
                   ))
               )

             (when (and (featurep 'semantic/db) (semanticdb-minor-mode-p))
               ;; Save everything.
               (semanticdb-save-all-db-idle)

               ;; Parse up files near our active buffer
               (when semantic-idle-work-parse-neighboring-files-flag
                 (semantic-safe "Idle Work Parse Neighboring Files: %S"
                   (set-buffer cb)
                   (semantic-idle-scheduler-work-parse-neighboring-files))
                 t)

               ;; Save everything... again
               (semanticdb-save-all-db-idle)
               )

             ;; Done w/ processing
             nil))))

    ;; Done
    (if interrupted
        "Interrupted"
      (cond ((not errbuf)
             "done")
            ((not (cdr errbuf))
             (format "done with 1 error in %s" (car errbuf)))
            (t
             (format "done with errors in %d buffers."
                     (length errbuf)))))))

(defun semantic-debug-idle-work-function ()
  "Run the Semantic idle work function with debugging turned on."
  (interactive)
  (let ((debug-on-error t))
    (semantic-idle-work-core-handler)
    ))

(defun semantic-idle-scheduler-work-function ()
  "Function run when after `semantic-idle-scheduler-work-idle-time'.
This routine handles difficult tasks that require a lot of parsing, such as
parsing all the header files used by our active sources, or building up complex
datasets."
  (when semantic-idle-scheduler-verbose-flag
    (message "Long Work Idle Timer..."))
  (let ((exit-type (save-match-data
                     (semantic-idle-work-core-handler))))
    (when semantic-idle-scheduler-verbose-flag
      (message "Long Work Idle Timer...%s" exit-type)))
  )

(defun semantic-idle-scheduler-work-parse-neighboring-files ()
  "Parse all the files in similar directories to buffers being edited."
  ;; Lets check to see if EDE matters.
  (let ((ede-auto-add-method 'never))
    (dolist (a auto-mode-alist)
      (when (eq (cdr a) major-mode)
        (dolist (file (directory-files default-directory t (car a) t))
          (semantic-throw-on-input 'parsing-mode-buffers)
          (save-excursion
            (semanticdb-file-table-object file)
            ))))
    ))

\f
;;; REPARSING
;;
;; Reparsing is installed as semantic idle service.
;; This part ALWAYS happens, and other services occur
;; afterwards.

(defvar semantic-before-idle-scheduler-reparse-hook nil
  "Hook run before option `semantic-idle-scheduler' begins parsing.
If any hook function throws an error, this variable is reset to nil.
This hook is not protected from lexical errors.")

(defvar semantic-after-idle-scheduler-reparse-hook nil
  "Hook run after option `semantic-idle-scheduler' has parsed.
If any hook function throws an error, this variable is reset to nil.
This hook is not protected from lexical errors.")

(semantic-varalias-obsolete 'semantic-before-idle-scheduler-reparse-hooks
                            'semantic-before-idle-scheduler-reparse-hook "23.2")
(semantic-varalias-obsolete 'semantic-after-idle-scheduler-reparse-hooks
                            'semantic-after-idle-scheduler-reparse-hook "23.2")

(defun semantic-idle-scheduler-refresh-tags ()
  "Refreshes the current buffer's tags.
This is called by `semantic-idle-scheduler-function' to update the
tags in the current buffer.

Return non-nil if the refresh was successful.
Return nil if there is some sort of syntax error preventing a full
reparse.

Does nothing if the current buffer doesn't need reparsing."

  (prog1
      ;; These checks actually occur in `semantic-fetch-tags', but if we
      ;; do them here, then all the bovination hooks are not run, and
      ;; we save lots of time.
      (cond
       ;; If the buffer was previously marked unparseable,
       ;; then don't waste our time.
       ((semantic-parse-tree-unparseable-p)
        nil)
       ;; The parse tree is already ok.
       ((semantic-parse-tree-up-to-date-p)
        t)
       (t
        ;; If the buffer might need a reparse and it is safe to do so,
        ;; give it a try.
        (let* (;(semantic-working-type nil)
               (inhibit-quit nil)
               ;; (working-use-echo-area-p
               ;;       (not semantic-idle-scheduler-working-in-modeline-flag))
               ;; (working-status-dynamic-type
               ;;       (if semantic-idle-scheduler-no-working-message
               ;;           nil
               ;;         working-status-dynamic-type))
               ;; (working-status-percentage-type
               ;;       (if semantic-idle-scheduler-no-working-message
               ;;           nil
               ;;         working-status-percentage-type))
               (lexically-safe t)
               )
          ;; Let people hook into this, but don't let them hose
          ;; us over!
          (condition-case nil
              (run-hooks 'semantic-before-idle-scheduler-reparse-hook)
            (error (setq semantic-before-idle-scheduler-reparse-hook nil)))

          (unwind-protect
              ;; Perform the parsing.
              (progn
                (when semantic-idle-scheduler-verbose-flag
                  (message "IDLE: reparse %s..." (buffer-name)))
                (when (semantic-lex-catch-errors idle-scheduler
                        (save-excursion (semantic-fetch-tags))
                        nil)
                  ;; If we are here, it is because the lexical step failed,
                  ;; proably due to unterminated lists or something like that.

                  ;; We do nothing, and just wait for the next idle timer
                  ;; to go off.  In the meantime, remember this, and make sure
                  ;; no other idle services can get executed.
                  (setq lexically-safe nil))
                (when semantic-idle-scheduler-verbose-flag
                  (message "IDLE: reparse %s...done" (buffer-name))))
            ;; Let people hook into this, but don't let them hose
            ;; us over!
            (condition-case nil
                (run-hooks 'semantic-after-idle-scheduler-reparse-hook)
              (error (setq semantic-after-idle-scheduler-reparse-hook nil))))
          ;; Return if we are lexically safe (from prog1)
          lexically-safe)))

    ;; After updating the tags, handle any pending decorations for this
    ;; buffer.
    (require 'semantic/decorate/mode)
    (semantic-decorate-flush-pending-decorations (current-buffer))
    ))

\f
;;; IDLE SERVICES
;;
;; Idle Services are minor modes which enable or disable a services in
;; the idle scheduler.  Creating a new services only requires calling
;; `semantic-create-idle-services' which does all the setup
;; needed to create the minor mode that will enable or disable
;; a services.  The services must provide a single function.

;; FIXME doc is incomplete.
(defmacro define-semantic-idle-service (name doc &rest forms)
  "Create a new idle services with NAME.
DOC will be a documentation string describing FORMS.
FORMS will be called during idle time after the current buffer's
semantic tag information has been updated.
This routine creates the following functions and variables:"
  (let ((global (intern (concat "global-" (symbol-name name) "-mode")))
        (mode   (intern (concat (symbol-name name) "-mode")))
        (hook   (intern (concat (symbol-name name) "-mode-hook")))
        (map    (intern (concat (symbol-name name) "-mode-map")))
        (func   (intern (concat (symbol-name name) "-idle-function"))))

    `(eval-and-compile
       (define-minor-mode ,global
         ,(concat "Toggle " (symbol-name global) ".
With ARG, turn the minor mode on if ARG is positive, off otherwise.

When this minor mode is enabled, `" (symbol-name mode) "' is
turned on in every Semantic-supported buffer.")
         :global t
         :group 'semantic
         :group 'semantic-modes
         :require 'semantic/idle
         (semantic-toggle-minor-mode-globally
          ',mode (if ,global 1 -1)))

       ;; FIXME: Get rid of this when define-minor-mode does it for us.
       (defcustom ,hook nil
         ,(concat "Hook run at the end of function `" (symbol-name mode) "'.")
         :group 'semantic
         :type 'hook)

       (defvar ,map
         (let ((km (make-sparse-keymap)))
           km)
         ,(concat "Keymap for `" (symbol-name mode) "'."))

       (define-minor-mode ,mode
         ,doc
         :keymap ,map
         (if ,mode
             (if (not (and (featurep 'semantic) (semantic-active-p)))
                 (progn
                   ;; Disable minor mode if semantic stuff not available
                   (setq ,mode nil)
                   (error "Buffer %s was not set up for parsing"
                          (buffer-name)))
               ;; Enable the mode mode
               (semantic-idle-scheduler-add #',func))
           ;; Disable the mode mode
           (semantic-idle-scheduler-remove #',func))
         (semantic-mode-line-update))

       (semantic-add-minor-mode ',mode
                                "")     ; idle schedulers are quiet?

       (defun ,func ()
         ,(concat "Perform idle activity for the minor mode `"
                  (symbol-name mode) "'.")
         ,@forms))))
(put 'define-semantic-idle-service 'lisp-indent-function 1)

\f
;;; SUMMARY MODE
;;
;; A mode similar to eldoc using semantic

(defcustom semantic-idle-summary-function
  'semantic-format-tag-summarize-with-file
  "Function to call when displaying tag information during idle time.
This function should take a single argument, a Semantic tag, and
return a string to display.
Some useful functions are found in `semantic-format-tag-functions'."
  :group 'semantic
  :type semantic-format-tag-custom-list)

(defsubst semantic-idle-summary-find-current-symbol-tag (sym)
  "Search for a semantic tag with name SYM in database tables.
Return the tag found or nil if not found.
If semanticdb is not in use, use the current buffer only."
  (car (if (and (featurep 'semantic/db)
                semanticdb-current-database
                (require 'semantic/db-find))
           (cdar (semanticdb-deep-find-tags-by-name sym))
         (semantic-deep-find-tags-by-name sym (current-buffer)))))

(defun semantic-idle-summary-current-symbol-info-brutish ()
  "Return a string message describing the current context.
Gets a symbol with `semantic-ctxt-current-thing' and then
tries to find it with a deep targeted search."
  ;; Try the current "thing".
  (let ((sym (car (semantic-ctxt-current-thing))))
    (when sym
      (semantic-idle-summary-find-current-symbol-tag sym))))

(defun semantic-idle-summary-current-symbol-keyword ()
  "Return a string message describing the current symbol.
Returns a value only if it is a keyword."
  ;; Try the current "thing".
  (let ((sym (car (semantic-ctxt-current-thing))))
    (if (and sym (semantic-lex-keyword-p sym))
        (semantic-lex-keyword-get sym 'summary))))

(defun semantic-idle-summary-current-symbol-info-context ()
  "Return a string message describing the current context.
Use the semantic analyzer to find the symbol information."
  (let ((analysis (condition-case nil
                      (semantic-analyze-current-context (point))
                    (error nil))))
    (when analysis
      (require 'semantic/analyze)
      (semantic-analyze-interesting-tag analysis))))

(defun semantic-idle-summary-current-symbol-info-default ()
  "Return a string message describing the current context.
This function will disable loading of previously unloaded files
by semanticdb as a time-saving measure."
  (let (
        (semanticdb-find-default-throttle
         (if (featurep 'semantic/db-find)
             (remq 'unloaded semanticdb-find-default-throttle)
           nil))
        )
    (save-excursion
      ;; use whicever has success first.
      (or
       (semantic-idle-summary-current-symbol-keyword)

       (semantic-idle-summary-current-symbol-info-context)

       (semantic-idle-summary-current-symbol-info-brutish)
       ))))

(defvar semantic-idle-summary-out-of-context-faces
  '(
    font-lock-comment-face
    font-lock-string-face
    font-lock-doc-string-face           ; XEmacs.
    font-lock-doc-face                  ; Emacs 21 and later.
    )
  "List of font-lock faces that indicate a useless summary context.
Those are generally faces used to highlight comments.

It might be useful to override this variable to add comment faces
specific to a major mode.  For example, in jde mode:

\(defvar-mode-local jde-mode semantic-idle-summary-out-of-context-faces
   (append (default-value 'semantic-idle-summary-out-of-context-faces)
           '(jde-java-font-lock-doc-tag-face
             jde-java-font-lock-link-face
             jde-java-font-lock-bold-face
             jde-java-font-lock-underline-face
             jde-java-font-lock-pre-face
             jde-java-font-lock-code-face)))")

(defun semantic-idle-summary-useful-context-p ()
  "Non-nil if we should show a summary based on context."
  (if (and (boundp 'font-lock-mode)
           font-lock-mode
           (memq (get-text-property (point) 'face)
                 semantic-idle-summary-out-of-context-faces))
      ;; The best I can think of at the moment is to disable
      ;; in comments by detecting with font-lock.
      nil
    t))

(define-overloadable-function semantic-idle-summary-current-symbol-info ()
  "Return a string message describing the current context.")

(make-obsolete-overload 'semantic-eldoc-current-symbol-info
                        'semantic-idle-summary-current-symbol-info
                        "23.2")

(defcustom semantic-idle-summary-mode-hook nil
  "Hook run at the end of `semantic-idle-summary'."
  :group 'semantic
  :type 'hook)

(defun semantic-idle-summary-idle-function ()
  "Display a tag summary of the lexical token under the cursor.
Call `semantic-idle-summary-current-symbol-info' for getting the
current tag to display information."
  (or (eq major-mode 'emacs-lisp-mode)
      (not (semantic-idle-summary-useful-context-p))
      (let* ((found (semantic-idle-summary-current-symbol-info))
             (str (cond ((stringp found) found)
                        ((semantic-tag-p found)
                         (funcall semantic-idle-summary-function
                                  found nil t)))))
        ;; Show the message with eldoc functions
        (unless (and str (boundp 'eldoc-echo-area-use-multiline-p)
                     eldoc-echo-area-use-multiline-p)
          (let ((w (1- (window-width (minibuffer-window)))))
            (if (> (length str) w)
                (setq str (substring str 0 w)))))
        (eldoc-message str))))

(define-minor-mode semantic-idle-summary-mode
  "Toggle Semantic Idle Summary mode.
With ARG, turn Semantic Idle Summary mode on if ARG is positive,
off otherwise.

When this minor mode is enabled, the echo area displays a summary
of the lexical token at point whenever Emacs is idle."
  :group 'semantic
  :group 'semantic-modes
  (if semantic-idle-summary-mode
      ;; Enable the mode
      (progn
        (unless (and (featurep 'semantic) (semantic-active-p))
          ;; Disable minor mode if semantic stuff not available
          (setq semantic-idle-summary-mode nil)
          (error "Buffer %s was not set up for parsing"
                 (buffer-name)))
        (require 'eldoc)
        (semantic-idle-scheduler-add 'semantic-idle-summary-idle-function)
        (add-hook 'pre-command-hook 'semantic-idle-summary-refresh-echo-area t))
    ;; Disable the mode
    (semantic-idle-scheduler-remove 'semantic-idle-summary-idle-function)
    (remove-hook 'pre-command-hook 'semantic-idle-summary-refresh-echo-area t))
  (semantic-mode-line-update))

(defun semantic-idle-summary-refresh-echo-area ()
  (and semantic-idle-summary-mode
       eldoc-last-message
       (if (and (not executing-kbd-macro)
                (not (and (boundp 'edebug-active) edebug-active))
                (not cursor-in-echo-area)
                (not (eq (selected-window) (minibuffer-window))))
           (eldoc-message eldoc-last-message)
         (setq eldoc-last-message nil))))

(semantic-add-minor-mode 'semantic-idle-summary-mode "")

(define-minor-mode global-semantic-idle-summary-mode
  "Toggle Global Semantic Idle Summary mode.
With ARG, turn Global Semantic Idle Summary mode on if ARG is
positive, off otherwise.

When this minor mode is enabled, `semantic-idle-summary-mode' is
turned on in every Semantic-supported buffer."
  :global t
  :group 'semantic
  :group 'semantic-modes
  (semantic-toggle-minor-mode-globally
   'semantic-idle-summary-mode
   (if global-semantic-idle-summary-mode 1 -1)))

\f
;;; Current symbol highlight
;;
;; This mode will use context analysis to perform highlighting
;; of all uses of the symbol that is under the cursor.
;;
;; This is to mimic the Eclipse tool of a similar nature.
(defvar semantic-idle-summary-highlight-face 'region
  "Face used for the summary highlight.")

(defun semantic-idle-summary-maybe-highlight (tag)
  "Perhaps add highlighting onto TAG.
TAG was found as the thing under point.  If it happens to be
visible, then highlight it."
  (require 'pulse)
  (let* ((region (when (and (semantic-tag-p tag)
                            (semantic-tag-with-position-p tag))
                   (semantic-tag-overlay tag)))
         (file (when (and (semantic-tag-p tag)
                          (semantic-tag-with-position-p tag))
                 (semantic-tag-file-name tag)))
         (buffer (when file (get-file-buffer file)))
         ;; We use pulse, but we don't want the flashy version,
         ;; just the stable version.
         (pulse-flag nil)
         )
    (cond ((semantic-overlay-p region)
           (with-current-buffer (semantic-overlay-buffer region)
             (goto-char (semantic-overlay-start region))
             (when (pos-visible-in-window-p
                    (point) (get-buffer-window (current-buffer) 'visible))
               (if (< (semantic-overlay-end region) (point-at-eol))
                   (pulse-momentary-highlight-overlay
                    region semantic-idle-summary-highlight-face)
                 ;; Not the same
                 (pulse-momentary-highlight-region
                  (semantic-overlay-start region)
                  (point-at-eol)
                  semantic-idle-summary-highlight-face)))
             ))
          ((vectorp region)
           (let ((start (aref region 0))
                 (end (aref region 1)))
             (save-excursion
               (when buffer (set-buffer buffer))
               ;; As a vector, we have no filename.  Perhaps it is a
               ;; local variable?
               (when (and (<= end (point-max))
                          (pos-visible-in-window-p
                           start (get-buffer-window (current-buffer) 'visible)))
                 (goto-char start)
                 (when (re-search-forward
                        (regexp-quote (semantic-tag-name tag))
                        end t)
                   ;; This is likely it, give it a try.
                   (pulse-momentary-highlight-region
                    start (if (<= end (point-at-eol)) end
                            (point-at-eol))
                    semantic-idle-summary-highlight-face)))
               ))))
    nil))

(define-semantic-idle-service semantic-idle-tag-highlight
  "Highlight the tag, and references of the symbol under point.
Call `semantic-analyze-current-context' to find the reference tag.
Call `semantic-symref-hits-in-region' to identify local references."
  (require 'pulse)
  (when (semantic-idle-summary-useful-context-p)
    (let* ((ctxt (semantic-analyze-current-context))
           (Hbounds (when ctxt (oref ctxt bounds)))
           (target (when ctxt (car (reverse (oref ctxt prefix)))))
           (tag (semantic-current-tag))
           ;; We use pulse, but we don't want the flashy version,
           ;; just the stable version.
           (pulse-flag nil))
      (when ctxt
        ;; Highlight the original tag?  Protect against problems.
        (condition-case nil
            (semantic-idle-summary-maybe-highlight target)
          (error nil))
        ;; Identify all hits in this current tag.
        (when (semantic-tag-p target)
          (require 'semantic/symref/filter)
          (semantic-symref-hits-in-region
           target (lambda (start end prefix)
                    (when (/= start (car Hbounds))
                      (pulse-momentary-highlight-region
                       start end semantic-idle-summary-highlight-face))
                    (semantic-throw-on-input 'symref-highlight)
                    )
           (semantic-tag-start tag)
           (semantic-tag-end tag)))
        ))))

\f
;;;###autoload
(define-minor-mode global-semantic-idle-scheduler-mode
  "Toggle global use of option `semantic-idle-scheduler-mode'.
The idle scheduler will automatically reparse buffers in idle time,
and then schedule other jobs setup with `semantic-idle-scheduler-add'.
If ARG is positive or nil, enable, if it is negative, disable."
  :global t
  :group 'semantic
  :group 'semantic-modes
  ;; When turning off, disable other idle modes.
  (when (null global-semantic-idle-scheduler-mode)
    (global-semantic-idle-summary-mode -1)
    (global-semantic-idle-tag-highlight-mode -1)
    (global-semantic-idle-completions-mode -1))
  (semantic-toggle-minor-mode-globally
   'semantic-idle-scheduler-mode
   (if global-semantic-idle-scheduler-mode 1 -1)))

\f
;;; Completion Popup Mode
;;
;; This mode uses tooltips to display a (hopefully) short list of possible
;; completions available for the text under point.  It provides
;; NO provision for actually filling in the values from those completions.

(defun semantic-idle-completion-list-default ()
  "Calculate and display a list of completions."
  (when (semantic-idle-summary-useful-context-p)
    ;; This mode can be fragile.  Ignore problems.
    ;; If something doesn't do what you expect, run
    ;; the below command by hand instead.
    (condition-case nil
        (let (
              ;; Don't go loading in oodles of header libraries in
              ;; IDLE time.
              (semanticdb-find-default-throttle
               (if (featurep 'semantic/db-find)
                   (remq 'unloaded semanticdb-find-default-throttle)
                 nil))
              )
          ;; Use idle version.
          (require 'semantic/complete)
          (semantic-complete-analyze-inline-idle)
          )
      (error nil))
    ))

(define-semantic-idle-service semantic-idle-completions
  "Toggle Semantic Idle Completions mode.
With ARG, turn Semantic Idle Completions mode on if ARG is
positive, off otherwise.

This minor mode only takes effect if Semantic is active and
`semantic-idle-scheduler-mode' is enabled.

When enabled, Emacs displays a list of possible completions at
idle time.  The method for displaying completions is given by
`semantic-complete-inline-analyzer-idle-displayor-class'; the
default is to show completions inline.

While a completion is displayed, RET accepts the completion; M-n
and M-p cycle through completion alternatives; TAB attempts to
complete as far as possible, and cycles if no additional
completion is possible; and any other command cancels the
completion.

\\{semantic-complete-inline-map}"
  ;; Add the ability to override sometime.
  (semantic-idle-completion-list-default))

(provide 'semantic/idle)

;; Local variables:
;; generated-autoload-file: "loaddefs.el"
;; generated-autoload-load-name: "semantic/idle"
;; End:

;; arch-tag: 4bfd54da-5023-4cc1-91ae-e1fefc1a8d1b
;;; semantic-idle.el ends here