bug#14509: Centerd calendar buffer

[E Sabof]

The following snippet will center the content of the calendar window. If there is interest in integrating this into emacs, I can reformat it as a patch. A possible interface to enable it could be (setq calendar-left-margin 'auto)

Evgeni

(require 'cl-lib)

(defun calendar-mode-options ()

  (setq calendar-left-margin 1)

  (add-hook 'window-configuration-change-hook

            'es-calendar-win-config-hook nil t))

(add-hook 'calendar-mode-hook 'calendar-mode-options)

(defun es-calendar-win-config-hook ()

  (catch 'exit

    (with-current-buffer

        (or (get-buffer calendar-buffer)

            (throw 'exit nil))

      (dolist (win (get-buffer-window-list nil nil t))

        (with-selected-window win

          (let* (( max (+ (* 7 3 3)

                          (* 2 calendar-intermonth-spacing)

                          -1))

                 ( left (max 0 (/ (- (window-body-width) max) 2))))

            (dolist (ov (overlays-in (point-min) (point-max)))

              (when (and (overlay-get ov 'left-center-margin)

                         (eq (selected-window)

                             (overlay-get ov 'window)))

                (delete-overlay ov)))

            (save-excursion

              (goto-char (point-min))

              (cl-loop for ov

                       = (make-overlay

                          (line-beginning-position)

                          (1+ (line-beginning-position)))

                       do (progn

                            (overlay-put ov 'window (selected-window))

                            (overlay-put ov 'display (make-string left ?\s ))

                            (overlay-put ov 'left-center-margin t)

                            )

                       while (zerop (forward-line))

                       ))))))))

(defadvice calendar-generate (after center-calendar activate)

  (es-calendar-win-config-hook))