prevent php-warnings, fixes #4829

Merge request studip/studip!3611

4 files changed, 15 insertions, 3 deletions

diff --git a/lib/classes/SemBrowse.class.php b/lib/classes/SemBrowse.class.php
index c1cae8d..a3e7c12 100644
--- a/lib/classes/SemBrowse.class.php
+++ b/lib/classes/SemBrowse.class.php
@@ -816,7 +816,7 @@ class SemBrowse {
                 uksort($group_by_data, function($a,$b) {
                     $the_tree = TreeAbstract::GetInstance('StudipSemTree', false);
                     $the_tree->buildIndex();
-                    return $the_tree->tree_data[$a]['index'] - $the_tree->tree_data[$b]['index'];
+                    return ($the_tree->tree_data[$a]['index'] ?? 0) - ($the_tree->tree_data[$b]['index'] ?? 0);
                 });
                 break;
             case 3:
diff --git a/lib/classes/Seminar.class.php b/lib/classes/Seminar.class.php
index 054c337..d9455d3 100644
--- a/lib/classes/Seminar.class.php
+++ b/lib/classes/Seminar.class.php
@@ -1278,7 +1278,8 @@ class Seminar
             $_SESSION['raumzeitFilter'] = 'all';
             $this->applyTimeFilter(0, 0);
         } else {
-            $filterSemester = Semester::findByTimestamp($timestamp);
+            $filterSemester = Semester::findByTimestamp($timestamp)
+                           ?? Semester::findCurrent();
             $_SESSION['raumzeitFilter'] = $filterSemester->beginn;
             $this->applyTimeFilter($filterSemester->beginn, $filterSemester->ende);
         }
diff --git a/lib/classes/calendar/CalendarScheduleModel.php b/lib/classes/calendar/CalendarScheduleModel.php
index 0aeadee..fdca8e3 100644
--- a/lib/classes/calendar/CalendarScheduleModel.php
+++ b/lib/classes/calendar/CalendarScheduleModel.php
@@ -676,6 +676,17 @@ class CalendarScheduleModel
             $schedule_settings['converted'] = true;
         }
 
+        if (empty($schedule_settings['glb_days'])) {
+            $schedule_settings['glb_days'] = [1, 2, 3, 4, 5];
+        }
+
+        if (empty($settings['glb_start_time'])) {
+            $schedule_settings['glb_start_time'] = 8;
+        }
+        if (empty($settings['glb_end_time'])) {
+            $schedule_settings['glb_end_time'] = 19;
+        }
+
         return $schedule_settings;
     }
 
diff --git a/lib/classes/sidebar/Sidebar.php b/lib/classes/sidebar/Sidebar.php
index b9d0338..822fa1b 100644
--- a/lib/classes/sidebar/Sidebar.php
+++ b/lib/classes/sidebar/Sidebar.php
@@ -145,7 +145,7 @@ class Sidebar extends WidgetContainer
                 $this->setContextAvatar($avatar);
             }
             if ($main_navigation === 'profile') {
-                if ($keys[1] !== "index") {
+                if (!empty($keys[1]) && $keys[1] !== 'index') {
                     $user = Request::get("username")
                         ? User::findByUsername(Request::get("username"))
                         : User::findCurrent();