appt.el trivia.

[bpt/emacs.git] / lisp / calendar / appt.el

;;; appt.el --- appointment notification functions

;; Copyright (C) 1989-1990, 1994, 1998, 2001-2011
;;   Free Software Foundation, Inc.

;; Author: Neil Mager <neilm@juliet.ll.mit.edu>
;; Maintainer: Glenn Morris <rgm@gnu.org>
;; Keywords: calendar
;; Package: calendar

;; 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:

;;
;; appt.el - visible and/or audible notification of
;;           appointments from diary file.
;;
;;
;; Thanks to  Edward M. Reingold for much help and many suggestions,
;; And to many others for bug fixes and suggestions.
;;
;;
;; This functions in this file will alert the user of a
;; pending appointment based on his/her diary file.  This package
;; is documented in the Emacs manual.
;;
;; To activate this package, simply use (appt-activate 1).
;; A `diary-file' with appointments of the format described in the
;; documentation of the function `appt-check' is required.
;; Relevant customizable variables are also listed in the
;; documentation of that function.
;;
;; Today's appointment list is initialized from the diary when this
;; package is activated.  Additionally, the appointments list is
;; recreated automatically at 12:01am for those who do not logout
;; every day or are programming late.  It is also updated when the
;; `diary-file' (or a file it includes) is saved.  Calling
;; `appt-check' with an argument (or re-enabling the package) forces a
;; re-initialization at any time.
;;
;; In order to add or delete items from today's list, without
;; changing the diary file, use `appt-add' and `appt-delete'.
;;

;; Brief internal description - Skip this if you are not interested!
;;
;; The function `appt-make-list' creates the appointments list which
;; `appt-check' reads.
;;
;; You can change the way the appointment window is created/deleted by
;; setting the variables
;;
;;           appt-disp-window-function
;; and
;;           appt-delete-window-function
;;
;; For instance, these variables could be set to functions that display
;; appointments in pop-up frames, which are lowered or iconified after
;; `appt-display-interval' minutes.
;;

;;; Code:

(require 'diary-lib)


(defgroup appt nil
  "Appointment notification."
  :prefix "appt-"
  :group 'calendar)

(defcustom appt-message-warning-time 12
  "Default time in minutes before an appointment that the warning begins."
  :type 'integer
  :group 'appt)

(defcustom appt-warning-time-regexp "warntime \\([0-9]+\\)"
  "Regexp matching a string giving the warning time for an appointment.
The first subexpression matches the time in minutes (an integer).
This overrides the default `appt-message-warning-time'.
You may want to put this inside a diary comment (see `diary-comment-start').
For example, to be warned 30 minutes in advance of an appointment:
   2011/06/01 12:00 Do something ## warntime 30
"
  :version "24.1"
  :type 'regexp
  :group 'appt)

(defcustom appt-audible t
  "Non-nil means beep to indicate appointment."
  :type 'boolean
  :group 'appt)

;; TODO - add popup.
(defcustom appt-display-format 'window
  "How appointment reminders should be displayed.
The options are:
   window - use a separate window
   echo   - use the echo area
   nil    - no visible reminder.
See also `appt-audible' and `appt-display-mode-line'."
  :type '(choice
          (const :tag "Separate window" window)
          (const :tag "Echo-area" echo)
          (const :tag "No visible display" nil))
  :group 'appt
  :version "24.1") ; no longer inherit from deleted obsolete variables

(defcustom appt-display-mode-line t
  "Non-nil means display minutes to appointment and time on the mode line.
This is in addition to any other display of appointment messages."
  :type 'boolean
  :group 'appt)

(defcustom appt-display-duration 10
  "The number of seconds an appointment message is displayed.
Only relevant if reminders are to be displayed in their own window."
  :type 'integer
  :group 'appt)

(defcustom appt-display-diary t
  "Non-nil displays the diary when the appointment list is first initialized.
This will occur at midnight when the appointment list is updated."
  :type 'boolean
  :group 'appt)

(defcustom appt-display-interval 3
  "Number of minutes to wait between checking the appointment list."
  :type 'integer
  :group 'appt)

(defcustom appt-disp-window-function 'appt-disp-window
  "Function called to display appointment window.
Only relevant if reminders are being displayed in a window.
It should take three string arguments: the number of minutes till
the appointment, the current time, and the text of the appointment."
  :type '(choice (const appt-disp-window)
                 function)
  :group 'appt)

(defcustom appt-delete-window-function 'appt-delete-window
  "Function called to remove appointment window and buffer.
Only relevant if reminders are being displayed in a window."
  :type '(choice (const appt-delete-window)
                 function)
  :group 'appt)


;;; Internal variables below this point.

(defconst appt-buffer-name "*appt-buf*"
  "Name of the appointments buffer.")

;; TODO Turn this into an alist?  It would be easier to add more
;; optional elements.
;; Why is the first element (MINUTES) rather than just MINUTES?
;; It may just inherit from diary-entries-list, where we have
;; ((MONTH DAY YEAR) ENTRY)
(defvar appt-time-msg-list nil
  "The list of appointments for today.
Use `appt-add' and `appt-delete' to add and delete appointments.
The original list is generated from today's `diary-entries-list', and
can be regenerated using the function `appt-check'.
Each element of the generated list has the form
\((MINUTES) STRING [FLAG] [WARNTIME])
where MINUTES is the time in minutes of the appointment after midnight,
and STRING is the description of the appointment.
FLAG and WARNTIME are not always present.  A non-nil FLAG
indicates that the element was made with `appt-add', so calling
`appt-make-list' again should preserve it.  If WARNTIME is non-nil,
it is an integer to use in place of `appt-message-warning-time'.")

(defconst appt-max-time (1- (* 24 60))
  "11:59pm in minutes - number of minutes in a day minus 1.")

(defvar appt-mode-string nil
  "String being displayed in the mode line saying you have an appointment.
The actual string includes the amount of time till the appointment.
Only used if `appt-display-mode-line' is non-nil.")
(put 'appt-mode-string 'risky-local-variable t) ; for 'face property

(defvar appt-prev-comp-time nil
  "Time of day (mins since midnight) at which we last checked appointments.
A nil value forces the diary file to be (re-)checked for appointments.")

(defvar appt-display-count nil
  "Internal variable used to count number of consecutive reminders.")

(defvar appt-timer nil
  "Timer used for diary appointment notifications (`appt-check').
If this is non-nil, appointment checking is active.")


;;; Functions.

(defun appt-display-message (string mins)
  "Display a reminder about an appointment.
The string STRING describes the appointment, due in integer MINS minutes.
The format of the visible reminder is controlled by `appt-display-format'.
The variable `appt-audible' controls the audible reminder."
  (if appt-audible (beep 1))
  (cond ((eq appt-display-format 'window)
         (funcall appt-disp-window-function
                  (number-to-string mins)
                  ;; TODO - use calendar-month-abbrev-array rather than %b?
                  (format-time-string "%a %b %e " (current-time))
                  string)
         (run-at-time (format "%d sec" appt-display-duration)
                      nil
                      appt-delete-window-function))
        ((eq appt-display-format 'echo)
         (message "%s" string))))


(defun appt-check (&optional force)
  "Check for an appointment and update any reminder display.
If optional argument FORCE is non-nil, reparse the diary file for
appointments.  Otherwise the diary file is only parsed once per day,
or when it (or a file it includes) is saved.

Note: the time must be the first thing in the line in the diary
for a warning to be issued.  The format of the time can be either
24 hour or am/pm.  For example:

              02/23/89
                18:00 Dinner

              Thursday
                11:45am Lunch meeting.

Appointments are checked every `appt-display-interval' minutes.
The following variables control appointment notification:

`appt-display-format'
        Controls the format in which reminders are displayed.

`appt-audible'
        Variable used to determine if reminder is audible.
        Default is t.

`appt-message-warning-time'
        Variable used to determine when appointment message
        should first be displayed.

`appt-display-mode-line'
        If non-nil, a generic message giving the time remaining
        is shown in the mode-line when an appointment is due.

`appt-display-interval'
        Interval in minutes at which to check for pending appointments.

`appt-display-diary'
        Display the diary buffer when the appointment list is
        initialized for the first time in a day.

The following variables are only relevant if reminders are being
displayed in a window:

`appt-display-duration'
        The number of seconds an appointment message is displayed.

`appt-disp-window-function'
        Function called to display appointment window.

`appt-delete-window-function'
        Function called to remove appointment window and buffer."
  (interactive "P")                     ; so people can force updates
  (let* ((min-to-app -1)
         (prev-appt-mode-string appt-mode-string)
         (prev-appt-display-count (or appt-display-count 0))
         now now-mins appt-mins appt-warn-time)
    (save-excursion                   ; FIXME ?
      ;; Convert current time to minutes after midnight (12.01am = 1).
      (setq now (decode-time)
            now-mins (+ (* 60 (nth 2 now)) (nth 1 now)))
      ;; At first check in any day, update appointments to today's list.
      (if (or force                      ; eg initialize, diary save
              (null appt-prev-comp-time) ; first check
              (< now-mins appt-prev-comp-time)) ; new day
          (ignore-errors
            (let ((diary-hook (if (assoc 'appt-make-list diary-hook)
                                  diary-hook
                                (cons 'appt-make-list diary-hook))))
              (if appt-display-diary
                  (diary)
                ;; Not displaying the diary, so we can ignore
                ;; diary-number-of-entries.  Since appt.el only
                ;; works on a daily basis, no need for more entries.
                (diary-list-entries (calendar-current-date) 1 t)))))
      (setq appt-prev-comp-time now-mins
            appt-mode-string nil
            appt-display-count nil)
      ;; Remove any entries that are in the past.
      ;; FIXME how can there be any such entries, given that this
      ;; function removes entries when they hit zero minutes,
      ;; and appt-make-list doesn't add any in the past in the first place?
      (while (and appt-time-msg-list
                  (< (setq appt-mins (caar (car appt-time-msg-list)))
                     now-mins))
        (setq appt-time-msg-list (cdr appt-time-msg-list)))
      ;; If there are entries in the list, and the user wants a
      ;; message issued, get the first time off of the list and
      ;; calculate the number of minutes until the appointment.
      (when appt-time-msg-list
        (setq appt-warn-time (or (nth 3 (car appt-time-msg-list))
                                 appt-message-warning-time)
              min-to-app (- appt-mins now-mins))
        ;; If we have an appointment between midnight and
        ;; `appt-warn-time' minutes after midnight, we
        ;; must begin to issue a message before midnight.  Midnight
        ;; is considered 0 minutes and 11:59pm is 1439
        ;; minutes.  Therefore we must recalculate the minutes to
        ;; appointment variable.  It is equal to the number of
        ;; minutes before midnight plus the number of minutes after
        ;; midnight our appointment is.
        ;; FIXME but appt-make-list constructs appt-time-msg-list to only
        ;; contain entries with today's date, so this cannot work?
        ;; Also above we just removed anything with appt-mins < now-mins.
        (if (and (< appt-mins appt-warn-time)
                 (> (+ now-mins appt-warn-time) appt-max-time))
            (setq min-to-app (+ (- (1+ appt-max-time) now-mins)
                                appt-mins)))
        ;; Issue warning if the appointment time is within
        ;; appt-message-warning time.
        (when (and (<= min-to-app appt-warn-time)
                   (>= min-to-app 0))
          ;; This is true every appt-display-interval minutes.
          (and (zerop (mod prev-appt-display-count appt-display-interval))
               (appt-display-message (cadr (car appt-time-msg-list))
                                     min-to-app))
          (when appt-display-mode-line
            (setq appt-mode-string
                  (concat " " (propertize
                               (format "App't %s"
                                       (if (zerop min-to-app) "NOW"
                                         (format "in %s min." min-to-app)))
                               'face 'mode-line-emphasis))))
          ;; When an appointment is reached, delete it from the
          ;; list.  Reset the count to 0 in case we display another
          ;; appointment on the next cycle.
          (if (zerop min-to-app)
              (setq appt-time-msg-list (cdr appt-time-msg-list)
                    appt-display-count nil)
            (setq appt-display-count (1+ prev-appt-display-count)))))
      ;; If we have changed the mode line string, redisplay all mode lines.
      (and appt-display-mode-line
           (not (string-equal appt-mode-string prev-appt-mode-string))
           (progn
             (force-mode-line-update t)
             ;; If the string now has a notification, redisplay right now.
             (if appt-mode-string
                 (sit-for 0)))))))

(defun appt-disp-window (min-to-app new-time appt-msg)
  "Display appointment due in MIN-TO-APP (a string) minutes.
NEW-TIME is a string giving the date.  Displays the appointment
message APPT-MSG in a separate buffer."
  (let ((this-window (selected-window))
        (appt-disp-buf (get-buffer-create appt-buffer-name)))
    ;; Make sure we're not in the minibuffer before splitting the window.
    ;; FIXME this seems needlessly complicated?
    (when (minibufferp)
      (other-window 1)
      (and (minibufferp) (display-multi-frame-p) (other-frame 1)))
    (if (cdr (assq 'unsplittable (frame-parameters)))
        ;; In an unsplittable frame, use something somewhere else.
        (progn
          (set-buffer appt-disp-buf)
          (display-buffer appt-disp-buf))
      (unless (or (special-display-p (buffer-name appt-disp-buf))
                  (same-window-p (buffer-name appt-disp-buf)))
        ;; By default, split the bottom window and use the lower part.
        (appt-select-lowest-window)
        ;; Split the window, unless it's too small to do so.
        (when (>= (window-height) (* 2 window-min-height))
          (select-window (split-window))))
      (switch-to-buffer appt-disp-buf))
    ;; FIXME Link to diary entry?
    (calendar-set-mode-line
     (format " Appointment %s. %s "
             (if (string-equal "0" min-to-app) "now"
               (format "in %s minute%s" min-to-app
                       (if (string-equal "1" min-to-app) "" "s")))
             new-time))
    (setq buffer-read-only nil
          buffer-undo-list t)
    (erase-buffer)
    (insert appt-msg)
    (shrink-window-if-larger-than-buffer (get-buffer-window appt-disp-buf t))
    (set-buffer-modified-p nil)
    (setq buffer-read-only t)
    (raise-frame (selected-frame))
    (select-window this-window)))

(defun appt-delete-window ()
  "Function called to undisplay appointment messages.
Usually just deletes the appointment buffer."
  (let ((window (get-buffer-window appt-buffer-name t)))
    (and window
         (or (eq window (frame-root-window (window-frame window)))
             (delete-window window))))
  (kill-buffer appt-buffer-name)
  (if appt-audible
      (beep 1)))

(defun appt-select-lowest-window ()
  "Select the lowest window on the frame."
  (let ((lowest-window (selected-window))
        (bottom-edge (nth 3 (window-edges)))
        next-bottom-edge)
    (walk-windows (lambda (w)
                    (when (< bottom-edge (setq next-bottom-edge
                                               (nth 3 (window-edges w))))
                      (setq bottom-edge next-bottom-edge
                            lowest-window w))) 'nomini)
    (select-window lowest-window)))

(defconst appt-time-regexp
  "[0-9]?[0-9]\\(h\\([0-9][0-9]\\)?\\|[:.][0-9][0-9]\\)\\(am\\|pm\\)?")

;;;###autoload
(defun appt-add (time msg &optional warntime)
  "Add an appointment for today at TIME with message MSG.
The time should be in either 24 hour format or am/pm format.
Optional argument WARNTIME is an integer (or string) giving the number
of minutes before the appointment at which to start warning.
The default is `appt-message-warning-time'."
  (interactive "sTime (hh:mm[am/pm]): \nsMessage: 
sMinutes before the appointment to start warning: ")
  (unless (string-match appt-time-regexp time)
    (error "Unacceptable time-string"))
  (and (stringp warntime)
       (setq warntime (unless (string-equal warntime "")
                        (string-to-number warntime))))
  (and warntime
       (not (integerp warntime))
       (error "Argument WARNTIME must be an integer, or nil"))
  (or appt-timer (appt-activate))
  (let ((time-msg (list (list (appt-convert-time time))
                        (concat time " " msg) t)))
    ;; It is presently non-sensical to have multiple warnings about
    ;; the same appointment with just different delays, but it might
    ;; not always be so.  TODO
    (if warntime (setq time-msg (append time-msg (list warntime))))
    (unless (member time-msg appt-time-msg-list)
      (setq appt-time-msg-list
            (appt-sort-list (nconc appt-time-msg-list (list time-msg)))))))

(defun appt-delete ()
  "Delete an appointment from the list of appointments."
  (interactive)
  (let ((tmp-msg-list appt-time-msg-list))
    (dolist (element tmp-msg-list)
      (if (y-or-n-p (concat "Delete "
                            ;; We want to quote any doublequotes in the
                            ;; string, as well as put doublequotes around it.
                            (prin1-to-string
                             (substring-no-properties (cadr element) 0))
                            " from list? "))
          (setq appt-time-msg-list (delq element appt-time-msg-list)))))
  (appt-check)
  (message ""))


(defvar number)
(defvar original-date)
(defvar diary-entries-list)

(defun appt-make-list ()
  "Update the appointments list from today's diary buffer.
The time must be at the beginning of a line for it to be
put in the appointments list (see examples in documentation of
the function `appt-check').  We assume that the variables DATE and
NUMBER hold the arguments that `diary-list-entries' received.
They specify the range of dates that the diary is being processed for.

Any appointments made with `appt-add' are not affected by this function."
  ;; We have something to do if the range of dates that the diary is
  ;; considering includes the current date.
  (if (and (not (calendar-date-compare
                 (list (calendar-current-date))
                 (list original-date)))
           (calendar-date-compare
            (list (calendar-current-date))
            (list (calendar-gregorian-from-absolute
                   (+ (calendar-absolute-from-gregorian original-date)
                      number)))))
      (save-excursion
        ;; Clear the appointments list, then fill it in from the diary.
        (dolist (elt appt-time-msg-list)
          ;; Delete any entries that were not made with appt-add.
          (unless (nth 2 elt)
            (setq appt-time-msg-list
                  (delq elt appt-time-msg-list))))
        (if diary-entries-list
            ;; Cycle through the entry-list (diary-entries-list)
            ;; looking for entries beginning with a time.  If the
            ;; entry begins with a time, add it to the
            ;; appt-time-msg-list.  Then sort the list.
            (let ((entry-list diary-entries-list)
                  time-string literal)
              ;; Below, we assume diary-entries-list was in date
              ;; order.  It is, unless something on
              ;; diary-list-entries-hook has changed it, eg
              ;; diary-include-other-files (bug#7019).  It must be
              ;; in date order if number = 1.
              (and diary-list-entries-hook
                   appt-display-diary
                   (not (eq diary-number-of-entries 1))
                   (not (memq (car (last diary-list-entries-hook))
                              '(diary-sort-entries sort-diary-entries)))
                   (setq entry-list (sort entry-list 'diary-entry-compare)))
              ;; Skip diary entries for dates before today.
              (while (and entry-list
                          (calendar-date-compare
                           (car entry-list) (list (calendar-current-date))))
                (setq entry-list (cdr entry-list)))
              ;; Parse the entries for today.
              (while (and entry-list
                          (calendar-date-equal
                           (calendar-current-date) (caar entry-list)))
                (setq time-string (cadr (car entry-list))
                      ;; Including any comments.
                      literal (or (nth 2 (nth 3 (car entry-list)))
                                  time-string))
                (while (string-match appt-time-regexp time-string)
                  (let* ((beg (match-beginning 0))
                         ;; Get just the time for this appointment.
                         (only-time (match-string 0 time-string))
                         ;; Find the end of this appointment
                         ;; (the start of the next).
                         (end (string-match
                               (concat "\n[ \t]*" appt-time-regexp)
                               time-string
                               (match-end 0)))
                         (warntime
                          (if (string-match appt-warning-time-regexp literal)
                              (string-to-number (match-string 1 literal))))
                         ;; Get the whole string for this appointment.
                         (appt-time-string
                          (substring time-string beg end))
                         ;; FIXME why the list?  It makes the first
                         ;; element (MINUTES) rather than MINUTES.
                         (appt-time (list (appt-convert-time only-time)))
                         (time-msg (append
                                    (list appt-time appt-time-string)
                                    (if warntime (list nil warntime)))))
                    ;; Add this appointment to appt-time-msg-list.
                    (setq appt-time-msg-list
                          (nconc appt-time-msg-list (list time-msg))
                          ;; Discard this appointment from the string.
                          ;; (This allows for multiple appts per entry.)
                          time-string
                          (if end (substring time-string end) ""))
                    ;; Similarly, discard the start of literal.
                    (and (> (length time-string) 0)
                         (string-match appt-time-regexp literal)
                         (setq end (string-match
                                    (concat "\n[ \t]*" appt-time-regexp)
                                    literal (match-end 0)))
                         (setq literal (substring literal end)))))
                (setq entry-list (cdr entry-list)))))
        (setq appt-time-msg-list (appt-sort-list appt-time-msg-list))
        ;; Convert current time to minutes after midnight (12:01am = 1),
        ;; and remove elements in the list that are in the past.
        (let* ((now (decode-time))
               (now-mins (+ (* 60 (nth 2 now)) (nth 1 now))))
          (while (and appt-time-msg-list
                      (< (caar (car appt-time-msg-list)) now-mins))
            (setq appt-time-msg-list (cdr appt-time-msg-list)))))))


(defun appt-sort-list (appt-list)
  "Sort an appointment list, putting earlier items at the front.
APPT-LIST is a list of the same format as `appt-time-msg-list'."
  (sort appt-list (lambda (e1 e2) (< (caar e1) (caar e2)))))


(defun appt-convert-time (time2conv)
  "Convert hour:min[am/pm] format TIME2CONV to minutes from midnight.
A period (.) can be used instead of a colon (:) to separate the
hour and minute parts."
  ;; Formats that should be accepted:
  ;;   10:00 10.00 10h00 10h 10am 10:00am 10.00am
  (let ((min (if (string-match "[h:.]\\([0-9][0-9]\\)" time2conv)
                 (string-to-number (match-string 1 time2conv))
               0))
        (hr (if (string-match "[0-9]*[0-9]" time2conv)
                (string-to-number (match-string 0 time2conv))
              0)))
    ;; Convert the time appointment time into 24 hour time.
    (cond ((and (string-match "pm" time2conv) (< hr 12))
           (setq hr (+ 12 hr)))
          ((and (string-match "am" time2conv) (= hr 12))
           (setq hr 0)))
    ;; Convert the actual time into minutes.
    (+ (* hr 60) min)))

(defun appt-update-list ()
  "If the current buffer is visiting the diary, update appointments.
This function also acts on any file listed in `diary-included-files'.
It is intended for use with `write-file-functions'."
  (and (member buffer-file-name (append diary-included-files
                                        (list (expand-file-name diary-file))))
       appt-timer
       (let ((appt-display-diary nil))
         (appt-check t)))
  nil)

;;;###autoload
(defun appt-activate (&optional arg)
  "Toggle checking of appointments.
With optional numeric argument ARG, turn appointment checking on if
ARG is positive, otherwise off."
  (interactive "P")
  (let ((appt-active appt-timer))
    (setq appt-active (if arg (> (prefix-numeric-value arg) 0)
                        (not appt-active)))
    (remove-hook 'write-file-functions 'appt-update-list)
    (or global-mode-string (setq global-mode-string '("")))
    (delq 'appt-mode-string global-mode-string)
    (when appt-timer
      (cancel-timer appt-timer)
      (setq appt-timer nil))
    (if appt-active
        (progn
          (add-hook 'write-file-functions 'appt-update-list)
          (setq appt-timer (run-at-time t 60 'appt-check)
                global-mode-string
                (append global-mode-string '(appt-mode-string)))
          (appt-check t)
          (message "Appointment reminders enabled%s"
                   ;; Someone might want to use appt-add without a diary.
                   (if (ignore-errors (diary-check-diary-file))
                       ""
                     " (no diary file found)")))
      (message "Appointment reminders disabled"))))


(provide 'appt)

;;; appt.el ends here