feat: extract references

Signed-off-by: Sebastian Krupinski <krupinski01@gmail.com>

lib/Client/Message.php

@@ -15,6 +15,7 @@ final class Message
      * @param list<MessageAddress> $cc
      * @param list<MessageAddress> $bcc
      * @param array<string, string> $bodySections
+     * @param list<string> $references message ids from the References header, without angle brackets
      */
     public function __construct(
         private readonly int $sequence,
@@ -35,6 +36,7 @@ final class Message
         private readonly array $bcc,
         private readonly ?MessagePart $bodyStructure,
         private readonly array $bodySections,
+        private readonly array $references = [],
     ) {}
 
     public function sequence(): int
@@ -90,6 +92,14 @@ final class Message
         return $this->inReplyTo;
     }
 
+    /**
+     * @return list<string>
+     */
+    public function references(): array
+    {
+        return $this->references;
+    }
+
     /**
      * @return list<MessageAddress>
      */
@@ -185,6 +195,7 @@ final class Message
             $this->bcc,
             $bodyStructure,
             $bodySections,
+            $this->references,
         );
     }
 }

lib/Client/Protocol/Parser/FetchMessageParser.php

@@ -46,7 +46,7 @@ final class FetchMessageParser
             self::decodeMimeHeader(self::envelopeString($envelope, 1)),
             self::envelopeString($envelope, 0),
             self::trimAngles(self::envelopeString($envelope, 9)),
-            self::envelopeString($envelope, 8),
+            self::trimAngles(self::envelopeString($envelope, 8)),
             self::parseAddressList($envelope[2] ?? null),
             self::parseAddressList($envelope[3] ?? null),
             self::parseAddressList($envelope[4] ?? null),
@@ -55,6 +55,7 @@ final class FetchMessageParser
             self::parseAddressList($envelope[7] ?? null),
             $bodyStructure,
             $bodySections,
+            self::extractReferences($headers),
         );
     }
 
@@ -351,6 +352,24 @@ final class FetchMessageParser
         return $parsed;
     }
 
+    /**
+     * Extract the message ids listed in the References header, without angle brackets.
+     *
+     * @param array<string, list<string>> $headers
+     * @return list<string>
+     */
+    private static function extractReferences(array $headers): array
+    {
+        $references = [];
+        foreach ($headers['references'] ?? [] as $value) {
+            if (preg_match_all('/<([^<>\s]+)>/', $value, $matches) > 0) {
+                array_push($references, ...$matches[1]);
+            }
+        }
+
+        return array_values(array_unique($references));
+    }
+
     /**
      * @param array<string, list<string>> $headers
      */