Merge branch 'hotfix/204-multiline-multibyte-headers'

Close #204
Fixes #194

Author: weierophinney

CHANGELOG.md

@@ -42,6 +42,9 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Fixed
 
+- [#204](https://github.com/zendframework/zend-mail/pull/204) fixes `HeaderWrap::mimeDecodeValue()` behavior when handling a multiline UTF-8
+  header split across a character. The fix will only work when ext-imap is present, however.
+
 - [#164](https://github.com/zendframework/zend-mail/pull/164) fixes the return value from `Zend\Mail\Protocol\Imap::capability()` when no response is
   returned from the server; previously, it returned `false`, but now correctly returns an empty array.
 

src/Header/HeaderWrap.php

@@ -110,9 +110,27 @@ public static function mimeDecodeValue($value)
 
         $decodedValue = iconv_mime_decode($value, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8');
 
+        // imap (unlike iconv) can handle multibyte headers which are splitted across multiple line
+        if (self::isNotDecoded($value, $decodedValue) && extension_loaded('imap')) {
+            return array_reduce(
+                imap_mime_header_decode(imap_utf8($value)),
+                function ($accumulator, $headerPart) {
+                    return $accumulator . $headerPart->text;
+                },
+                ''
+            );
+        }
+
         return $decodedValue;
     }
 
+    private static function isNotDecoded($originalValue, $value)
+    {
+        return 0 === strpos($value, '=?')
+            && strlen($value) - 2 === strpos($value, '?=')
+            && false !== strpos($originalValue, $value);
+    }
+
     /**
      * Test if is possible apply MIME-encoding
      *

test/Header/HeaderWrapTest.php

@@ -113,4 +113,24 @@ public function testCanBeEncoded()
         $res = HeaderWrap::canBeEncoded($value);
         $this->assertTrue($res);
     }
+
+    /**
+     * @requires extension imap
+     */
+    public function testMultilineWithMultibyteSplitAcrossCharacter()
+    {
+        $originalValue = 'аф';
+
+        $this->assertEquals(strlen($originalValue), 4);
+
+        $part1 = base64_encode(substr($originalValue, 0, 3));
+        $part2 = base64_encode(substr($originalValue, 3));
+
+        $header = '=?utf-8?B?' . $part1 . '?==?utf-8?B?' . $part2 . '?=';
+
+        $this->assertEquals(
+            $originalValue,
+            HeaderWrap::mimeDecodeValue($header)
+        );
+    }
 }