--- loncom/interface/lonannounce.pm	2006/04/23 07:16:07	1.51
+++ loncom/interface/lonannounce.pm	2006/05/12 02:17:50	1.52
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Announce
 #
-# $Id: lonannounce.pm,v 1.51 2006/04/23 07:16:07 albertel Exp $
+# $Id: lonannounce.pm,v 1.52 2006/05/12 02:17:50 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -326,9 +326,43 @@ function dialin(day,month,year) {
 </script>
 ENDDIA
 }
+# ----------------------------------------------------- Summarize all calendars
+sub get_all_calendars {
+    my %allcal=();
+    foreach my $course (sort(&Apache::loncommon::findallcourses())) {
+	%allcal=(%allcal,&readcalendar($course));
+    }
+    return %allcal;
+}
+
+sub output_ics_file {
+    my ($r)=@_;
+# RFC 2445 wants CRLF
+    my $crlf="\015\012";
+# Header
+    $r->print("BEGIN:VCALENDAR$crlf");
+    $r->print("VERSION:2.0$crlf");
+    $r->print("PRODID:-//LONCAPA//LONCAPA Calendar Output//EN$crlf");
+    my %allcal=&get_all_calendars();
+    foreach my $event (keys(%allcal)) {
+	my ($course,$startdate,$enddate)=($event=~/^(\w+)\@(\d+)\_(\d+)$/);
+	$r->print("BEGIN:VEVENT$crlf");
+	$r->print("DTSTART:".&Apache::loncommon::utc_string($startdate).$crlf);
+	$r->print("DTEND:".&Apache::loncommon::utc_string($enddate).$crlf);
+	$r->print("SUMMARY:$allcal{$event}$crlf");
+	$r->print("END:VEVENT$crlf");
+    }
+# Footer
+    $r->print("END:VCALENDAR$crlf");
+}
 
 sub handler {
     my $r = shift;
+    if ($r->uri=~/\.(ics|ical)$/) {
+        &Apache::loncommon::content_type($r,'text/calendar');
+	&output_ics_file($r);
+	return OK;
+    }
     &Apache::loncommon::content_type($r,'text/html');
     $r->send_http_header;
     return OK if $r->header_only;
@@ -479,11 +513,7 @@ SERVERANNOUNCE
         &editfield($r,$today,$tomorrow,'');
     }
 # ----------------------------------------------------- Summarize all calendars
-    my %allcal=();
-    foreach my $course (sort(&Apache::loncommon::findallcourses())) {
-	%allcal=(%allcal,&readcalendar($course));
-    }
-
+    my %allcal=&get_all_calendars();
 # ------------------------------- Initialize table and forward backward buttons
     my ($pm,$py,$fm,$fy)=($month-1,$year,$month+1,$year);
     if ($pm<1) { ($pm,$py)=(12,$year-1); }