fix: more resilient date format

fixes: #72 thank you @batgithub

Author: mauricerenck

app/Feed.php

@@ -4,6 +4,8 @@
 
 use Kirby\Toolkit\Xml;
 use Kirby\Toolkit\Str;
+use IntlDateFormatter;
+
 
 class Feed extends Podcast
 {
@@ -145,4 +147,10 @@ public function getTranscript($episode)
 
         return $transcriptList;
     }
+
+    public function getRssDate($timestamp)
+    {
+        $formatter = new IntlDateFormatter('en_US', IntlDateFormatter::FULL, IntlDateFormatter::FULL, 'UTC', IntlDateFormatter::GREGORIAN, "EEE, dd MMM yyyy HH:mm:ss +0000");
+        return datefmt_format($formatter,$timestamp);
+    }
 }

snippets/xml/item.php

@@ -5,13 +5,14 @@
 $feed = new Feed();
 $useUuid = option('mauricerenck.podcaster.feed.uuid', false);
 $audioFile = $feed->getAudioFile($episode);
+$pubDate = $feed->getRssDate($episode->date()->modified()->toDate());
 
 if(is_null($audioFile)) {
     return;
 }
 ?>
 <item>
-    <?=$feed->xmlTag('pubDate', $episode->date()->toDate(DATE_RSS));?>
+    <?=$feed->xmlTag('pubDate', $pubDate);?>
 
     <?=$feed->xmlTag('title', $episode->podcasterTitle()->or($episode->title()));?>
     <?=$feed->xmlTag('itunes:title', $episode->podcasterTitle()->or($episode->title()));?>

templates/podcasterfeed.php

@@ -8,6 +8,7 @@
 $feed = new Feed();
 kirby()->response()->type('application/rss+xml');
 //kirby()->response()->type('text/xml'); // TODO for debugging
+
 ?>
 <?php snippet('podcaster-feed-header'); ?>
 
@@ -73,4 +74,4 @@
             <?php snippet('podcaster-feed-item', ['episode' => $episode]); ?>
         <?php endforeach; ?>
     </channel>
-</rss>
+</rss>