From 8c6f0adc66423283642ecfdf301266f79cb1b9d2 Mon Sep 17 00:00:00 2001
From: the-djmaze <>
Date: Mon, 12 Aug 2024 16:50:11 +0200
Subject: [PATCH] Improved handling of RFC 2822 dates #1694

---
 .../libraries/MailSo/Base/DateTimeHelper.php    | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/snappymail/v/0.0.0/app/libraries/MailSo/Base/DateTimeHelper.php b/snappymail/v/0.0.0/app/libraries/MailSo/Base/DateTimeHelper.php
index 09a626a99..c4cb6c4bc 100644
--- a/snappymail/v/0.0.0/app/libraries/MailSo/Base/DateTimeHelper.php
+++ b/snappymail/v/0.0.0/app/libraries/MailSo/Base/DateTimeHelper.php
@@ -31,7 +31,7 @@ abstract class DateTimeHelper
 
 	/**
 	 * Parse date string formated as "Thu, 10 Jun 2010 08:58:33 -0700 (PDT)"
-	 * RFC 2822
+	 * https://www.rfc-editor.org/rfc/rfc2822#section-3.3
 	 */
 	public static function ParseRFC2822DateString(string $sDateTime) : int
 	{
@@ -41,10 +41,19 @@ abstract class DateTimeHelper
 			return 0;
 		}
 
-		$sDateTime = \trim(\preg_replace('/ \([a-zA-Z0-9]+\)$/', '', $sDateTime));
+		// Strip invalid data after zone, https://github.com/the-djmaze/snappymail/issues/1554
+		$sDateTime = \preg_replace('/\s+\([a-zA-Z0-9]+\)$/', '', $sDateTime);
+		// https://github.com/the-djmaze/snappymail/issues/1694#issuecomment-2270983942
+		// Strip day-of-week
+		$sDateTime = \preg_replace('/^[^,]+,/', '', $sDateTime);
+		// Add optional seconds
 		$sDateTime = \preg_replace('/ ([0-9]+:[0-9]+) /', ' $1:00 ', $sDateTime);
-		$oDateTime = \DateTime::createFromFormat(\DateTime::RFC2822, $sDateTime, static::GetUtcTimeZoneObject())
-			?: \DateTime::createFromFormat('d M Y H:i:s O', $sDateTime, static::GetUtcTimeZoneObject());
+		$sDateTime = \trim($sDateTime);
+		$oDateTime =
+			// Using O (difference to Greenwich time (GMT) without colon between hours and minutes)
+			\DateTime::createFromFormat('d M Y H:i:s O', $sDateTime, static::GetUtcTimeZoneObject())
+			// Using T (obsolete timezone abbreviation)
+			?: \DateTime::createFromFormat('d M Y H:i:s T', $sDateTime, static::GetUtcTimeZoneObject());
 		// 398045302 is 1982-08-13 00:08:22 the date RFC 822 was created
 		if (!$oDateTime || 398045302 > $oDateTime->getTimestamp()) {
 			\SnappyMail\Log::notice('', "Failed to parse RFC 2822 date '{$sDateTime}'");