From a34c13fd9421a062986f04b7e3cefff6c0719551 Mon Sep 17 00:00:00 2001
From: Ralf Becker <RalfBecker@outdoor-training.de>
Date: Mon, 8 Nov 2021 18:01:18 +0100
Subject: [PATCH] fix PHP 8.0 error: Illegal offset type when PUTint an all-day
 series

---
 calendar/inc/class.calendar_ical.inc.php | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/calendar/inc/class.calendar_ical.inc.php b/calendar/inc/class.calendar_ical.inc.php
index c026b4ffc0..330bcdafdc 100644
--- a/calendar/inc/class.calendar_ical.inc.php
+++ b/calendar/inc/class.calendar_ical.inc.php
@@ -2706,6 +2706,11 @@ class calendar_ical extends calendar_boupdate
 					break;
 				case 'RECURRENCE-ID':
 				case 'X-RECURRENCE-ID':
+					if (is_array($attributes['value'])) // whole-day event recurrence-id is returned as array
+					{
+						$attributes['value'] = mktime(0, 0, 0,
+							$attributes['value']['month'], $attributes['value']['mday'], $attributes['value']['year']);
+					}
 					$vcardData['recurrence'] = $attributes['value'];
 					break;
 				case 'LOCATION':