cal-move.el 12.1 KB
Newer Older
Edward M. Reingold's avatar
Edward M. Reingold committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
;;; cal-move.el --- calendar functions for movement in the calendar

;; Copyright (C) 1995 Free Software Foundation, Inc.

;; Author: Edward M. Reingold <reingold@cs.uiuc.edu>
;; Keywords: calendar
;; Human-Keywords: 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 2, 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
Erik Naggum's avatar
Erik Naggum committed
22 23 24
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.
Edward M. Reingold's avatar
Edward M. Reingold committed
25 26 27 28 29 30 31 32 33 34 35 36 37 38

;;; Commentary:

;; This collection of functions implements movement in the calendar for
;; calendar.el.

;; Comments, corrections, and improvements should be sent to
;;  Edward M. Reingold               Department of Computer Science
;;  (217) 333-6733                   University of Illinois at Urbana-Champaign
;;  reingold@cs.uiuc.edu             1304 West Springfield Avenue
;;                                   Urbana, Illinois 61801

;;; Code:

Richard M. Stallman's avatar
Richard M. Stallman committed
39 40
(require 'calendar)

Edward M. Reingold's avatar
Edward M. Reingold committed
41 42 43 44 45 46 47
(defun calendar-goto-today ()
  "Reposition the calendar window so the current date is visible."
  (interactive)
  (let ((today (calendar-current-date)));; The date might have changed.
    (if (not (calendar-date-is-visible-p today))
        (generate-calendar-window)
      (update-calendar-mode-line)
48 49
      (calendar-cursor-to-visible-date today)))
  (run-hooks 'calendar-move-hook))
Edward M. Reingold's avatar
Edward M. Reingold committed
50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67

(defun calendar-forward-month (arg)
  "Move the cursor forward ARG months.
Movement is backward if ARG is negative."
  (interactive "p")
  (calendar-cursor-to-nearest-date)
  (let* ((cursor-date (calendar-cursor-to-date t))
         (month (extract-calendar-month cursor-date))
         (day (extract-calendar-day cursor-date))
         (year (extract-calendar-year cursor-date)))
    (increment-calendar-month month year arg)
    (let ((last (calendar-last-day-of-month month year)))
      (if (< last day)
        (setq day last)))
    ;; Put the new month on the screen, if needed, and go to the new date.
    (let ((new-cursor-date (list month day year)))
      (if (not (calendar-date-is-visible-p new-cursor-date))
          (calendar-other-month month year))
68 69
      (calendar-cursor-to-visible-date new-cursor-date)))
  (run-hooks 'calendar-move-hook))
Edward M. Reingold's avatar
Edward M. Reingold committed
70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88

(defun calendar-forward-year (arg)
  "Move the cursor forward by ARG years.
Movement is backward if ARG is negative."
  (interactive "p")
  (calendar-forward-month (* 12 arg)))

(defun calendar-backward-month (arg)
  "Move the cursor backward by ARG months.
Movement is forward if ARG is negative."
  (interactive "p")
  (calendar-forward-month (- arg)))

(defun calendar-backward-year (arg)
  "Move the cursor backward ARG years.
Movement is forward is ARG is negative."
  (interactive "p")
  (calendar-forward-month (* -12 arg)))

Dave Love's avatar
Dave Love committed
89
(defun scroll-calendar-left (&optional arg)
Edward M. Reingold's avatar
Edward M. Reingold committed
90 91 92 93
  "Scroll the displayed calendar left by ARG months.
If ARG is negative the calendar is scrolled right.  Maintains the relative
position of the cursor with respect to the calendar as well as possible."
  (interactive "p")
Dave Love's avatar
Dave Love committed
94
  (unless arg (setq arg 1))
Edward M. Reingold's avatar
Edward M. Reingold committed
95 96 97 98
  (calendar-cursor-to-nearest-date)
  (let ((old-date (calendar-cursor-to-date))
        (today (calendar-current-date)))
    (if (/= arg 0)
99 100 101 102
        (let ((month displayed-month)
	      (year displayed-year))
          (increment-calendar-month month year arg)
	  (generate-calendar-window month year)
Edward M. Reingold's avatar
Edward M. Reingold committed
103 104 105 106
          (calendar-cursor-to-visible-date
           (cond
            ((calendar-date-is-visible-p old-date) old-date)
            ((calendar-date-is-visible-p today) today)
107 108
            (t (list month 1 year)))))))
  (run-hooks 'calendar-move-hook))
Edward M. Reingold's avatar
Edward M. Reingold committed
109

Dave Love's avatar
Dave Love committed
110
(defun scroll-calendar-right (&optional arg)
Edward M. Reingold's avatar
Edward M. Reingold committed
111 112 113 114
  "Scroll the displayed calendar window right by ARG months.
If ARG is negative the calendar is scrolled left.  Maintains the relative
position of the cursor with respect to the calendar as well as possible."
  (interactive "p")
Dave Love's avatar
Dave Love committed
115
  (scroll-calendar-left (- (or arg 1))))
Edward M. Reingold's avatar
Edward M. Reingold committed
116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174

(defun scroll-calendar-left-three-months (arg)
  "Scroll the displayed calendar window left by 3*ARG months.
If ARG is negative the calendar is scrolled right.  Maintains the relative
position of the cursor with respect to the calendar as well as possible."
  (interactive "p")
  (scroll-calendar-left (* 3 arg)))

(defun scroll-calendar-right-three-months (arg)
  "Scroll the displayed calendar window right by 3*ARG months.
If ARG is negative the calendar is scrolled left.  Maintains the relative
position of the cursor with respect to the calendar as well as possible."
  (interactive "p")
  (scroll-calendar-left (* -3 arg)))

(defun calendar-cursor-to-nearest-date ()
  "Move the cursor to the closest date.
The position of the cursor is unchanged if it is already on a date.
Returns the list (month day year) giving the cursor position."
  (let ((date (calendar-cursor-to-date))
        (column (current-column)))
    (if date
        date
      (if (> 3 (count-lines (point-min) (point)))
          (progn
            (goto-line 3)
            (move-to-column column)))
      (if (not (looking-at "[0-9]"))
          (if (and (not (looking-at " *$"))
                   (or (< column 25)
                       (and (> column 27)
                            (< column 50))
                       (and (> column 52)
                            (< column 75))))
              (progn
                (re-search-forward "[0-9]" nil t)
                (backward-char 1))
            (re-search-backward "[0-9]" nil t)))
      (calendar-cursor-to-date))))

(defun calendar-forward-day (arg)
  "Move the cursor forward ARG days.
Moves backward if ARG is negative."
  (interactive "p")
  (if (/= 0 arg)
      (let*
          ((cursor-date (calendar-cursor-to-date))
           (cursor-date (if cursor-date
                            cursor-date
                          (if (> arg 0) (setq arg (1- arg)))
                          (calendar-cursor-to-nearest-date)))
           (new-cursor-date
            (calendar-gregorian-from-absolute
             (+ (calendar-absolute-from-gregorian cursor-date) arg)))
           (new-display-month (extract-calendar-month new-cursor-date))
           (new-display-year (extract-calendar-year new-cursor-date)))
        ;; Put the new month on the screen, if needed, and go to the new date.
        (if (not (calendar-date-is-visible-p new-cursor-date))
            (calendar-other-month new-display-month new-display-year))
175 176
        (calendar-cursor-to-visible-date new-cursor-date)))
  (run-hooks 'calendar-move-hook))
Edward M. Reingold's avatar
Edward M. Reingold committed
177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250

(defun calendar-backward-day (arg)
  "Move the cursor back ARG days.
Moves forward if ARG is negative."
  (interactive "p")
  (calendar-forward-day (- arg)))

(defun calendar-forward-week (arg)
  "Move the cursor forward ARG weeks.
Moves backward if ARG is negative."
  (interactive "p")
  (calendar-forward-day (* arg 7)))

(defun calendar-backward-week (arg)
  "Move the cursor back ARG weeks.
Moves forward if ARG is negative."
  (interactive "p")
  (calendar-forward-day (* arg -7)))

(defun calendar-beginning-of-week (arg)
  "Move the cursor back ARG calendar-week-start-day's."
  (interactive "p")
  (calendar-cursor-to-nearest-date)
  (let ((day (calendar-day-of-week (calendar-cursor-to-date))))
    (calendar-backward-day
     (if (= day calendar-week-start-day)
         (* 7 arg)
       (+ (mod (- day calendar-week-start-day) 7)
          (* 7 (1- arg)))))))

(defun calendar-end-of-week (arg)
  "Move the cursor forward ARG calendar-week-start-day+6's."
  (interactive "p")
  (calendar-cursor-to-nearest-date)
  (let ((day (calendar-day-of-week (calendar-cursor-to-date))))
    (calendar-forward-day
     (if (= day (mod (1- calendar-week-start-day) 7))
         (* 7 arg)
       (+ (- 6 (mod (- day calendar-week-start-day) 7))
          (* 7 (1- arg)))))))

(defun calendar-beginning-of-month (arg)
  "Move the cursor backward ARG month beginnings."
  (interactive "p")
  (calendar-cursor-to-nearest-date)
  (let* ((date (calendar-cursor-to-date))
         (month (extract-calendar-month date))
         (day (extract-calendar-day date))
         (year (extract-calendar-year date)))
    (if (= day 1)
        (calendar-backward-month arg)
      (calendar-cursor-to-visible-date (list month 1 year))
      (calendar-backward-month (1- arg)))))

(defun calendar-end-of-month (arg)
  "Move the cursor forward ARG month ends."
  (interactive "p")
  (calendar-cursor-to-nearest-date)
  (let* ((date (calendar-cursor-to-date))
         (month (extract-calendar-month date))
         (day (extract-calendar-day date))
         (year (extract-calendar-year date))
         (last-day (calendar-last-day-of-month month year)))
    (if (/= day last-day)
        (progn
          (calendar-cursor-to-visible-date (list month last-day year))
          (setq arg (1- arg))))
    (increment-calendar-month month year arg)
    (let ((last-day (list
                     month
                     (calendar-last-day-of-month month year)
                     year)))
      (if (not (calendar-date-is-visible-p last-day))
          (calendar-other-month month year)
251 252
      (calendar-cursor-to-visible-date last-day))))
  (run-hooks 'calendar-move-hook))
Edward M. Reingold's avatar
Edward M. Reingold committed
253 254 255 256 257 258 259 260 261

(defun calendar-beginning-of-year (arg)
  "Move the cursor backward ARG year beginnings."
  (interactive "p")
  (calendar-cursor-to-nearest-date)
  (let* ((date (calendar-cursor-to-date))
         (month (extract-calendar-month date))
         (day (extract-calendar-day date))
         (year (extract-calendar-year date))
262 263
         (jan-first (list 1 1 year))
         (calendar-move-hook nil))
Edward M. Reingold's avatar
Edward M. Reingold committed
264 265 266 267 268
    (if (and (= day 1) (= 1 month))
        (calendar-backward-month (* 12 arg))
      (if (and (= arg 1)
               (calendar-date-is-visible-p jan-first))
          (calendar-cursor-to-visible-date jan-first)
269 270
        (calendar-other-month 1 (- year (1- arg))))))
  (run-hooks 'calendar-move-hook))
Edward M. Reingold's avatar
Edward M. Reingold committed
271 272 273 274 275 276 277 278 279

(defun calendar-end-of-year (arg)
  "Move the cursor forward ARG year beginnings."
  (interactive "p")
  (calendar-cursor-to-nearest-date)
  (let* ((date (calendar-cursor-to-date))
         (month (extract-calendar-month date))
         (day (extract-calendar-day date))
         (year (extract-calendar-year date))
280 281
         (dec-31 (list 12 31 year))
         (calendar-move-hook nil))
Edward M. Reingold's avatar
Edward M. Reingold committed
282 283 284 285 286 287
    (if (and (= day 31) (= 12 month))
        (calendar-forward-month (* 12 arg))
      (if (and (= arg 1)
               (calendar-date-is-visible-p dec-31))
          (calendar-cursor-to-visible-date dec-31)
        (calendar-other-month 12 (- year (1- arg)))
288 289
        (calendar-cursor-to-visible-date (list 12 31 displayed-year)))))
  (run-hooks 'calendar-move-hook))
Edward M. Reingold's avatar
Edward M. Reingold committed
290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323

(defun calendar-cursor-to-visible-date (date)
  "Move the cursor to DATE that is on the screen."
  (let* ((month (extract-calendar-month date))
	 (day (extract-calendar-day date))
	 (year (extract-calendar-year date))
	 (first-of-month-weekday (calendar-day-of-week (list month 1 year))))
    (goto-line (+ 3
		  (/ (+ day  -1
                        (mod
                         (- (calendar-day-of-week (list month 1 year))
                            calendar-week-start-day)
                         7))
                     7)))
    (move-to-column (+ 6
		       (* 25
			  (1+ (calendar-interval
			       displayed-month displayed-year month year)))
		       (* 3 (mod
                             (- (calendar-day-of-week date)
                                calendar-week-start-day)
                             7))))))

(defun calendar-goto-date (date)
  "Move cursor to DATE."
  (interactive (list (calendar-read-date)))
  (let ((month (extract-calendar-month date))
        (year (extract-calendar-year date)))
    (if (not (calendar-date-is-visible-p date))
        (calendar-other-month
         (if (and (= month 1) (= year 1))
             2
           month)
         year)))
324 325
  (calendar-cursor-to-visible-date date)
  (run-hooks 'calendar-move-hook))
Edward M. Reingold's avatar
Edward M. Reingold committed
326 327 328 329

(provide 'cal-move)

;;; cal-move.el ends here