ics: print the timezone name in the ICS file

Add the correct timezone in generated ICS files.  The timezone is
fetched from /etc/timezone.

Even though this is not standard, if a tool needs it, it should be able
to understand it correctly.

Signed-off-by: Alban Gruin <alban at pa1ch dot fr>

1 files changed, 13 insertions, 1 deletions

diff --git a/src/ics.ml b/src/ics.ml
index 6dd747d..d1bb808 100644
--- a/src/ics.ml
+++ b/src/ics.ml
@@ -61,8 +61,19 @@ type t = Event.t list
 
 let make events = events
 
-let to_string events =
+let gen_vtimezone tz =
+  if tz <> "" then
+  ["BEGIN:VTIMEZONE";
+   "TZID:" ^ tz;
+   "END:VTIMEZONE\n"]
+  |> List.map ics_split_line
+  |> String.concat "\n"
+  else
+    ""
+
+let to_string tz events =
   let date = current_date () in
+  let vtimezone = gen_vtimezone tz in
   let rec gen_events id str = function
     | [] -> str
     | event :: l ->
@@ -70,5 +81,6 @@ let to_string events =
   "BEGIN:VCALENDAR\n\
    VERSION:2.0\n\
    PRODID:-//ucs//\n"
+  ^ vtimezone
   ^ gen_events 0 "" events
   ^ "END:VCALENDAR\n"