Add earlier work on timezones.

Add earlier work on timezones, with a few inline modifications. This is
really to big of a commit. But we are so far from a stable release that
it should be fine.

The current version seems to eager, and recalculates to many times. This
will soon be fixed in a future version.

1 files changed, 12 insertions, 10 deletions

diff --git a/module/vcalendar/datetime.scm b/module/vcalendar/datetime.scm
index f6df03d5..9b1cc82d 100644
--- a/module/vcalendar/datetime.scm
+++ b/module/vcalendar/datetime.scm
@@ -2,22 +2,24 @@
   #:use-module (vcalendar)
   #:use-module (srfi srfi-19)
   #:use-module (srfi srfi-19 util)
+  #:use-module (util)
 
   #:export (parse-datetime
             event-overlaps?
-            event-in?)
+            event-in?
+            ev-time<?)
   )
 
+;;; date time pointer
 (define (parse-datetime dtime)
   "Parse the given date[time] string into a date object."
-  ;; localize-date
-  (date->time-utc
-   (string->date
-    dtime
-    (case (string-length dtime)
-      ((8) "~Y~m~d")
-      ((15) "~Y~m~dT~H~M~S")
-      ((16) "~Y~m~dT~H~M~S~z")))))
+  (let* ((str type (case (string-length dtime)
+                     ((8) (values "~Y~m~d" 'all-day))        ; All day
+                     ((15) (values "~Y~m~dT~H~M~S" 'local))  ; "local" or TZID-param
+                     ((16) (values "~Y~m~dT~H~M~S~z" 'utc))  ; UTC-time
+                     ))
+         (date (string->date dtime str)))
+    (values date type)))
 
 (define (event-overlaps? event begin end)
   "Returns if the event overlaps the timespan.
@@ -33,6 +35,6 @@ Event must have the DTSTART and DTEND attribute set."
          (end (add-day start)))
     (event-overlaps? ev start end)))
 
-(define-public (ev-time<? a b)
+(define (ev-time<? a b)
   (time<? (attr a 'DTSTART)
           (attr b 'DTSTART)))