Implement better handling of deadlines in iCalendar Export.

Deadlines in TODO entries are now used as DUE dates.

ORGWEBPAGE/Changes.org

@@ -10,11 +10,43 @@
 #+LINK_UP: index.html
 #+LINK_HOME: http://orgmode.org
 
-* Version 6.05
+* Version 6.06
 :PROPERTIES:
 :VISIBILITY: content
 :END:
 
+** Overview
+** Details
+*** Changes in iCalendar export
+    Deadline and scheduling time stamps are now treated
+    differently in iCalendar export.  The default behavior is now
+    the following:
+
+    - a DEADLINE that appears in an entry that is a TODO item is
+      used as the item's DUE date.  Therefore, such a deadline
+      will no longer show up in the calendar.
+
+    - a DEADLINE that appears in an item that is *not* a TODO
+      item is exported as an EVENT and will show up in the
+      calendar.
+
+    - a SCHEDULED timestamp in a TODO item will be used as the
+      items DTSTART.  Therefore, such a timestamp will not show
+      up in the calendar.
+
+    - a SCHEDULED timestamp in an item that is not a TODO has no
+      effect on iCalendar export at all.  It will be ignored.
+
+    Of course this would not be Emacs if you could not configure
+    exactly what you want.  Take a look at the variables
+    =org-icalendar-use-deadlines= and
+    =org-icalendar-use-deadlines= if you want to go back to the
+    old behavior or even do something completely different.
+
+    Thanks to Karen Cooke for triggering this change.
+
+* Version 6.05
+
 If I were to name my releases, this one would be called "Adam".
 Adam, you definitely owe me a beer :-).  And I owe you one, too -
 thanks for all the great ideas.

doc/org.texi

@@ -7546,13 +7546,18 @@ Export only the visible part of the document.
 @section iCalendar export
 @cindex iCalendar export
 
-Some people like to use Org mode for keeping track of projects, but
-still prefer a standard calendar application for anniversaries and
-appointments.  In this case it can be useful to have deadlines and
-other time-stamped items in Org files show up in the calendar
-application.  Org mode can export calendar information in the standard
-iCalendar format.  If you also want to have TODO entries included in the
-export, configure the variable @code{org-icalendar-include-todo}.
+Some people like to use Org mode for keeping track of projects, but still
+prefer a standard calendar application for anniversaries and appointments.
+In this case it can be useful to have deadlines and other time-stamped items
+in Org files show up in the calendar application.  Org mode can export
+calendar information in the standard iCalendar format.  If you also want to
+have TODO entries included in the export, configure the variable
+@code{org-icalendar-include-todo}.  iCalendar export will export plain time
+stamps as VEVENT, and TODO items as VTODO.  It will also create events from
+deadlines that are in non-TODO items.  Deadlines and scheduling dates in TODO
+items will be used to set the start and due dates for the todo
+entry@footnote{See the variables @code{org-icalendar-use-deadline} and
+@code{org-icalendar-use-scheduled}.}.
 
 The iCalendar standard requires each entry to have a globally unique
 identifier (UID).  Org creates these identifiers during export.  If you set
@@ -7586,7 +7591,7 @@ the selected entries have them.  If not, the summary will be derived
 from the headline, and the description from the body (limited to
 @code{org-icalendar-include-body} characters).
 
-How this calendar is best read and updated, depends on the application
+How this calendar is best read and updated, that depends on the application
 you are using.  The FAQ covers this issue.
 
 @node Publishing, Miscellaneous, Exporting, Top

lisp/ChangeLog

@@ -1,5 +1,11 @@
 2008-06-23  Carsten Dominik  <dominik@science.uva.nl>
 
+	* org-exp.el (org-icalendar-use-deadline)
+	(org-icalendar-use-scheduled): New options.
+	(org-icalendar-include-todo): Default changed to t.
+	(org-print-icalendar-entries): Implement better utilization of
+	scheduling and deadline time stamps.
+
 	* org-clock.el (org-clocktable-shift): Also undertand yesterday,
 	lastweek etc.
 	(org-clock-special-range): Also undertand yesterday, lastweek etc.

lisp/org-exp.el

@@ -625,6 +625,46 @@ The file name should be absolute, the file will be overwritten without warning."
   :group 'org-export-icalendar
   :type 'file)
 
+(defcustom org-icalendar-combined-name "OrgMode"
+  "Calendar name for the combined iCalendar representing all agenda files."
+  :group 'org-export-icalendar
+  :type 'string)
+
+(defcustom org-icalendar-use-deadline '(event-if-not-todo todo-due)
+  "Contexts where iCalendar export should use a deadline time stamp.
+This is a list with several symbols in it.  Valid symbol are:
+
+event-if-todo       Deadlines in TODO entries become calendar events.
+event-if-not-todo   Deadlines in non-TODO entries become calendar events.
+todo-due            Use deadlines in TODO entries as due-dates"
+  :group 'org-export-icalendar
+  :type '(set :greedy t
+	      (const :tag "Deadlines in non-TODO entries become events"
+		     event-if-not-todo)
+	      (const :tag "Deadline in TODO entries become events"
+		     event-if-todo)
+	      (const :tag "Deadlines in TODO entries become due-dates"
+		     todo-due)))
+
+(defcustom org-icalendar-use-scheduled '(todo-start)
+  "Contexts where iCalendar export should use a scheduling time stamp.
+This is a list with several symbols in it.  Valid symbol are:
+
+event-if-todo       Scheduling time stamps in TODO entries become an event.
+event-if-not-todo   Scheduling time stamps in non-TODO entries become an event.
+todo-start          Scheduling time stamps in TODO entries become start date.
+                    Some calendar applications show TODO entries only after
+                    that date."
+  :group 'org-export-icalendar
+  :type '(set :greedy t
+	      (const :tag
+		     "SCHEDULED timestamps in non-TODO entries become events"
+		     event-if-not-todo)
+	      (const :tag "SCHEDULED timestamps in TODO entries become events"
+		     event-if-todo)
+	      (const :tag "SCHEDULED in TODO entries become start date"
+		     todo-start)))
+
 (defcustom org-icalendar-include-todo nil
   "Non-nil means, export to iCalendar files should also cover TODO items."
   :group 'org-export-icalendar
@@ -650,11 +690,6 @@ The text will be inserted into the DESCRIPTION field."
 	  (const :tag "Everything" t)
 	  (integer :tag "Max characters")))
 
-(defcustom org-icalendar-combined-name "OrgMode"
-  "Calendar name for the combined iCalendar representing all agenda files."
-  :group 'org-export-icalendar
-  :type 'string)
-
 (defcustom org-icalendar-store-UID nil
   "Non-nil means, store any created UIDs in properties.
 The iCalendar standard requires that all entries have a unique identifyer.
@@ -3933,7 +3968,7 @@ When COMBINE is non nil, add the category to each line."
 	      (format-time-string (cdr org-time-stamp-formats) (current-time))
 	      "DTSTART"))
 	hd ts ts2 state status (inc t) pos b sexp rrule
-	scheduledp deadlinep prefix
+	scheduledp deadlinep todo prefix due start
 	tmp pri category entry location summary desc uid
 	(sexp-buffer (get-buffer-create "*ical-tmp*")))
     (org-refresh-category-properties)
@@ -3982,8 +4017,21 @@ When COMBINE is non nil, add the category to each line."
 			ts)
 		  deadlinep (string-match org-deadline-regexp tmp)
 		  scheduledp (string-match org-scheduled-regexp tmp)
+		  todo (org-get-todo-state)
 		  ;; donep (org-entry-is-done-p)
 		  ))
+	  (when (and
+		 deadlinep
+		 (if todo
+		     (not (memq 'event-if-todo org-icalendar-use-deadline))
+		   (not (memq 'event-if-not-todo org-icalendar-use-deadline))))
+	    (throw :skip t))
+	  (when (and
+		 scheduledp
+		 (if todo
+		     (not (memq 'event-if-todo org-icalendar-use-scheduled))
+		   (not (memq 'event-if-not-todo org-icalendar-use-scheduled))))
+	    (throw :skip t))
 	  (setq prefix (if deadlinep "DL-" (if scheduledp "SC-" "TS-")))
 	  (if (or (string-match org-tr-regexp hd)
 		  (string-match org-ts-regexp hd))
@@ -4071,9 +4119,16 @@ END:VEVENT\n"
 			  t org-icalendar-include-body)
 		    location (org-icalendar-cleanup-string
 			      (org-entry-get nil "LOCATION"))
+		    due (and (member 'todo-due org-icalendar-use-deadline)
+			     (org-entry-get nil "DEADLINE"))
+		    start (and (member 'todo-start org-icalendar-use-scheduled)
+			     (org-entry-get nil "SCHEDULED"))
 		    uid (if org-icalendar-store-UID
 			    (org-id-get-create)
 			  (or (org-id-get) (org-id-new))))
+	      (and due (setq due (org-ical-ts-to-string due "DUE")))
+	      (and start (setq start (org-ical-ts-to-string start "DTSTART")))
+
 	      (if (string-match org-bracket-link-regexp hd)
 		  (setq hd (replace-match (if (match-end 3) (match-string 3 hd)
 					    (match-string 1 hd))
@@ -4089,19 +4144,20 @@ END:VEVENT\n"
 	      (princ (format "BEGIN:VTODO
 UID: %s
 %s
-SUMMARY:%s%s%s
+SUMMARY:%s%s%s%s
 CATEGORIES:%s
 SEQUENCE:1
 PRIORITY:%d
 STATUS:%s
 END:VTODO\n"
 			     (concat prefix uid)
-			     dts
+			     (or start dts)
 			     (or summary hd)
 			     (if (and location (string-match "\\S-" location))
 				 (concat "\nLOCATION: " location) "")
 			     (if (and desc (string-match "\\S-" desc))
 				 (concat "\nDESCRIPTION: " desc) "")
+			     (if due (concat "\n" due) "")
 			     category
 			     pri status)))))))))