Improve PHP 8 compatibility

Trying to access non-existent array fields is a warning in PHP 8.
Though this error is masked by ddeboer/transcoder#5 in the integration tests when mbstring extension is available.

Also, Dice uses `ReflectionParameter::getClass()`, which is deprecated in PHP 8. Since we have not yet set an error handler at that point because it needs a `Logger` class instantiated by Dice, let’s disable deprecation warnings temporarily. Unfortunately, we cannot just re-enable them and log them in the error handler since fatfree’s error handler is extremely inflexible bcosca/fatfree#999.

src/common.php

@@ -25,6 +25,11 @@
 
 $f3 = Base::instance();
 
+// Disable deprecation warnings.
+// Dice uses ReflectionParameter::getClass(), which is deprecated in PHP 8
+// but we have not set an error handler yet because it needs a Logger instantiated by Dice.
+error_reporting(E_ALL & ~E_DEPRECATED);
+
 $f3->set('DEBUG', 0);
 $f3->set('version', '2.19-SNAPSHOT');
 
@@ -203,6 +208,7 @@
 
 // init logger
 $log = $dice->create(Logger::class);
+
 if ($f3->get('logger_level') === 'NONE') {
     $handler = new NullHandler();
 } else {

src/controllers/Index.php

@@ -127,8 +127,8 @@ private function loadItems(array $params, array $tags) {
         $itemsHtml = '';
 
         $firstPage = $params['offset'] == 0
-            && $params['fromId'] == ''
-            && $params['fromDatetime'] == '';
+            && (!isset($params['fromId']) || $params['fromId'] == '')
+            && (!isset($params['fromDatetime']) || $params['fromDatetime'] == '');
         if ($params['source'] && $this->authentication->allowedToUpdate() && $firstPage) {
             $itemsHtml = '<button type="button" id="refresh-source" class="refresh-source">' . \F3::get('lang_source_refresh') . '</button>';
         }

src/controllers/Sources/Write.php

@@ -83,16 +83,16 @@ public function write(Base $f3, array $params) {
         }
         $tags = array_map('htmlspecialchars', $data['tags']);
         $spout = $data['spout'];
-        $filter = $data['filter'];
+        $filter = isset($data['filter']) ? $data['filter'] : null;
 
         unset($data['title']);
         unset($data['spout']);
         unset($data['filter']);
         unset($data['tags']);
 
         // check if source already exists
-        $id = $params['id'];
-        $sourceExists = $this->sourcesDao->isValid('id', $id);
+        $id = isset($params['id']) ? $params['id'] : null;
+        $sourceExists = $id !== null && $this->sourcesDao->isValid('id', $id);
 
         // load password value if not changed for spouts containing passwords
         if ($sourceExists) {

src/helpers/ContentLoader.php

@@ -215,7 +215,9 @@ public function fetch($source) {
                 'datetime' => $itemDate->format('Y-m-d H:i:s'),
                 'uid' => $item->getId(),
                 'link' => htmLawed($item->getLink(), ['deny_attribute' => '*', 'elements' => '-*']),
-                'author' => $author
+                'author' => $author,
+                'thumbnail' => null,
+                'icon' => null,
             ];
 
             $thumbnailUrl = $item->getThumbnail();