prevent php-warnings, fixes #4829

Merge request studip/studip!3611

13 files changed, 54 insertions, 22 deletions

diff --git a/app/controllers/avatar.php b/app/controllers/avatar.php
index aafbb98..9068a82 100644
--- a/app/controllers/avatar.php
+++ b/app/controllers/avatar.php
@@ -129,8 +129,12 @@ class AvatarController extends AuthenticatedController
                 $imgdata = Request::get('cropped-image');
 
                 // Extract actual image data (prepended by mime type and meta data)
-                list($type, $imgdata) = explode(';', $imgdata);
-                list(, $imgdata) = explode(',', $imgdata);
+                $chunks = explode(';', $imgdata);
+                $type = $chunks[0];
+                $imgdata = $chunks[1] ?? '';
+
+                $chunks = explode(',', $imgdata);
+                $imgdata = $chunks[1] ?? '';
                 $imgdata = base64_decode($imgdata);
                 // Write data to file.
                 $filename = $GLOBALS['TMP_PATH'] . '/avatar-' . $id . '.png';
diff --git a/lib/classes/SemBrowse.class.php b/lib/classes/SemBrowse.class.php
index c1cae8d..a3e7c12 100644
--- a/lib/classes/SemBrowse.class.php
+++ b/lib/classes/SemBrowse.class.php
@@ -816,7 +816,7 @@ class SemBrowse {
                 uksort($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();
diff --git a/lib/evaluation/classes/EvaluationExportManager.class.php b/lib/evaluation/classes/EvaluationExportManager.class.php
index 0c88e7f..08fd5e2 100644
--- a/lib/evaluation/classes/EvaluationExportManager.class.php
+++ b/lib/evaluation/classes/EvaluationExportManager.class.php
@@ -233,10 +233,14 @@ class EvaluationExportManager extends AuthorObject
             $file = $GLOBALS['TMP_PATH'] . "/" . $file;
             $part = pathinfo($file);
 
-            if (filemtime($file) < (time() - EVALEXPORT_LIFETIME) &&
-                $part["extension"] == $this->extension &&
-                mb_substr($part["basename"], 0, mb_strlen(EVALEXPORT_PREFIX)) == EVALEXPORT_PREFIX)
+            if (
+                filemtime($file) < (time() - EVALEXPORT_LIFETIME)
+                && isset($part['extension'])
+                && $part['extension'] === $this->extension
+                && mb_substr($part['basename'], 0, mb_strlen(EVALEXPORT_PREFIX)) == EVALEXPORT_PREFIX
+            ) {
                 unlink($file);
+            }
         }
         $dirhandle->close();
     }
@@ -264,4 +268,3 @@ class EvaluationExportManager extends AuthorObject
     }
 
 }
-
diff --git a/lib/evaluation/classes/EvaluationExportManagerCSV.class.php b/lib/evaluation/classes/EvaluationExportManagerCSV.class.php
index 4baa3f8..f236457 100644
--- a/lib/evaluation/classes/EvaluationExportManagerCSV.class.php
+++ b/lib/evaluation/classes/EvaluationExportManagerCSV.class.php
@@ -273,10 +273,14 @@ class EvaluationExportManagerCSV extends EvaluationExportManager {
             /* Questiontype: pol or likert scale --------------------------- */
             if ($type == EVALQUESTION_TYPE_LIKERT ||
                 $type == EVALQUESTION_TYPE_POL) {
-               $hasResidual = $this->evalquestions_residual[$evalquestion->getObjectID()];
+               $hasResidual = $this->evalquestions_residual[$evalquestion->getObjectID()] ?? '';
                $entry       = "";
                $residual    = 0;
-               if ($answer = $answers[$evalquestion->getObjectID()][$userID]) {
+               $answer = [];
+               if ($evalquestion->getObjectID() && !empty($answers[$evalquestion->getObjectID()])) {
+                   $answer = $answers[$evalquestion->getObjectID()][$userID];
+               }
+               if (!empty($answer)) {
                    if ($answer['residual']) {
                        $residual = 1;
                    } else {
@@ -295,7 +299,12 @@ class EvaluationExportManagerCSV extends EvaluationExportManager {
             /* Questiontype: multiple chioice ------------------------------ */
             elseif ($type == EVALQUESTION_TYPE_MC) {
                 if ($evalquestion->isMultiplechoice ()) {
-                    $mc_answers = explode(',', $answers[$evalquestion->getObjectID()][$userID]['evalanswer_id']);
+                    if ($evalquestion->getObjectID()) {
+                        $mc_answers = $answers[$evalquestion->getObjectID()][$userID]['evalanswer_id'] ?? [];
+                    } else {
+                        $mc_answers = [];
+                    }
+                    $mc_answers = explode(',', $mc_answers);
                     while ($answer = &$evalquestion->getNextChild ()) {
                         $this->addCol ((int)in_array($answer->getObjectID(), $mc_answers));
                     }
diff --git a/lib/evaluation/classes/EvaluationTreeEditView.class.php b/lib/evaluation/classes/EvaluationTreeEditView.class.php
index 3bfe92a..0fbbe08 100644
--- a/lib/evaluation/classes/EvaluationTreeEditView.class.php
+++ b/lib/evaluation/classes/EvaluationTreeEditView.class.php
@@ -1210,15 +1210,15 @@ class EvaluationTreeEditView
                             $no_answers++;
                     }
                     if ($no_answers == 1) {
-                        if ($this->msg[$this->itemID])
+                        if (!empty($this->msg[$this->itemID]))
                             $this->msg[$this->itemID] .= "<br>" . _("Einer Frage wurden noch keine Antwortenmöglichkeiten zugewiesen.");
                         else
-                            $this->msg[$this->itemID] .= "info§" . _("Einer Frage  wurden noch keine Antwortenmöglichkeiten zugewiesen.");
+                            $this->msg[$this->itemID] = "info§" . _("Einer Frage  wurden noch keine Antwortenmöglichkeiten zugewiesen.");
                     } elseif ($no_answers > 1) {
-                        if ($this->msg[$this->itemID])
+                        if (!empty($this->msg[$this->itemID]))
                             $this->msg[$this->itemID] .= "<br>" . sprintf(_("%s Fragen wurden noch keine Antwortenmöglichkeiten zugewiesen."), $no_answers);
                         else
-                            $this->msg[$this->itemID] .= "info§" . sprintf(_("%s Fragen wurden noch keine Antwortenmöglichkeiten zugewiesen."), $no_answers);
+                            $this->msg[$this->itemID] = "info§" . sprintf(_("%s Fragen wurden noch keine Antwortenmöglichkeiten zugewiesen."), $no_answers);
                     }
 
                 }
@@ -1507,6 +1507,7 @@ class EvaluationTreeEditView
         $qgroup = &$this->tree->getGroupObject($this->itemID);
         $questionsDB = $qgroup->getChildren();
         $cmd = Request::optionArray('cmd');
+        $delete_empty_questions = 0;
         if (!empty($cmd))
             if (key($cmd) == "UpdateItem")
                 $delete_empty_questions = 1;
diff --git a/lib/evaluation/classes/EvaluationTreeShowUser.class.php b/lib/evaluation/classes/EvaluationTreeShowUser.class.php
index e999cb5..9968ff0 100644
--- a/lib/evaluation/classes/EvaluationTreeShowUser.class.php
+++ b/lib/evaluation/classes/EvaluationTreeShowUser.class.php
@@ -507,7 +507,7 @@ class EvaluationTreeShowUser
                                     ? "checked"
                                     : "";
                             else
-                                $checked = (is_array($answers[$question->getObjectID()]) &&
+                                $checked = (!empty($answers[$question->getObjectID()]) &&
                                     in_array($answer->getObjectID(), $answers[$question->getObjectID()]))
                                     ? "checked"
                                     : "";
diff --git a/lib/meine_seminare_func.inc.php b/lib/meine_seminare_func.inc.php
index 297bf3f..f0b5940 100644
--- a/lib/meine_seminare_func.inc.php
+++ b/lib/meine_seminare_func.inc.php
@@ -83,7 +83,7 @@ function sort_groups($group_field, &$groups)
         case 'sem_tree_id':
             uksort($groups, function ($a, $b) {
                 $the_tree = TreeAbstract::GetInstance('StudipSemTree', ['build_index' => true]);
-                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;
 
diff --git a/public/eval_summary_export.php b/public/eval_summary_export.php
index 77b349a..118cd92 100644
--- a/public/eval_summary_export.php
+++ b/public/eval_summary_export.php
@@ -138,7 +138,10 @@ function do_graph($data, $evalquestion_id)
     );
 
     if(!empty($data)) {
-        $max_x = max(array_map('next',$data));
+        array_walk($data, function($d) use (&$_data) {
+            $_data[] = next($d);
+        });
+        $max_x = max($_data);
         $graph->SetPlotAreaWorld(NULL, 0); // y-achse bei 0 starten
         $graph->SetPrecisionY(0); //anzahl kommastellen y-achse
         $graph->SetYTickIncrement($max_x < 10 ? 1 : round($max_x/10));
@@ -169,7 +172,7 @@ function freetype_answers ($parent_id, $anz_nutzer) {
               ORDER BY position";
     $statement = DBManager::get()->prepare($query);
     $statement->execute([$parent_id]);
-
+    $counter = 0;
     while ($answer = $statement->fetchColumn()) {
         $counter++;
         fputs($fo_file,"                <fo:table-row>\n");
diff --git a/public/show_bereich.php b/public/show_bereich.php
index 2a5e55d..94bda5e 100644
--- a/public/show_bereich.php
+++ b/public/show_bereich.php
@@ -47,7 +47,7 @@ if (Request::option('select_sem')) {
     $_SESSION['_default_sem'] = Request::option('select_sem');
 }
 
-$show_semester = Request::option('select_sem', $_SESSION['_default_sem']);
+$show_semester = Request::option('select_sem', $_SESSION['_default_sem'] ?? '');
 $sem_browse_obj = new SemBrowse(['group_by' => 0]);
 $sem_browse_obj->sem_browse_data['default_sem'] = "all";
 $sem_browse_obj->sem_number = false;
diff --git a/public/show_evaluation.php b/public/show_evaluation.php
index e81510a..76f6c1f 100644
--- a/public/show_evaluation.php
+++ b/public/show_evaluation.php
@@ -240,7 +240,7 @@ page_close();
            ( is_array($answers) &&
          ! in_array($item->getObjectID(), array_keys($answers)) )
            ) &&
-         trim($freetexts[$item->getObjectID()]) == ''
+         empty($freetexts[$item->getObjectID()])
          )
          {
              $mandatories[] = $item->getObjectID();