Here are the settings I use for diary loaded into org-mode. You need to get urls for the apple calendars you want to show in org.
I found the discussion by Adolfo
Villafiorita very helpful.
You'll also probably want to set up some sort of script to automate checking your calendars for new entries. I think the easiest way to do this is to run a script for emacs in batch mode.
(setq diary-file (concat cpm-local-dir "diary-files/diary"))
(setq diary-location (concat cpm-local-dir "diary-files/"))
(setq org-agenda-include-diary t)
(setq diary-display-function 'diary-fancy-display)
(add-hook 'diary-list-entries-hook 'diary-include-other-diary-files)
(add-hook 'diary-list-entries-hook 'diary-sort-entries t)
; calendars you want to download
; each item links to a remote iCal calendar
'(("work" . "https://path/to/work/cal")
("gcal" . "https://path/to/gcal")
("family" . "https://path/to/fam/cal")
(defun cpm--getcal (url file)
"Download ics file and add it to file"
(let ((tmpfile (url-file-local-copy url)))
(icalendar-import-file tmpfile file)
(kill-buffer (car (last (split-string tmpfile "/"))))))
(defun cpm/getcals ()
"Load a set of ics calendars into emacs diary files"
(mapcar #'(lambda (x)
(let ((file (concat diary-location (car x)))
(url (cdr x)))
(message (concat "Loading " url " into " file))
;; (flush-lines "^[& ]") ;; if you import ical as non marking
(erase-buffer) ;; to avoid duplicating events
(cpm--getcal url file)
;; send everything to a diary file
(shell-command-to-string "cat work family gcal > diary"))