From 20ae1cfcf07517baadbaac9f3bbf2a06416227a7 Mon Sep 17 00:00:00 2001
From: kolydart <kolydart@macbeth.gateweb.gr>
Date: Sun, 16 Apr 2017 10:19:26 +0300
Subject: [PATCH] New protected method VCard::chunk_split_unicode() to handle
 utf8 strings during VCard::fold(); with tests

---
 src/VCard.php       | 22 +++++++++++++++++++++-
 tests/VCardTest.php | 19 +++++++++++++++++++
 2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/src/VCard.php b/src/VCard.php
index ffacd9f..9fdcf57 100644
--- a/src/VCard.php
+++ b/src/VCard.php
@@ -546,7 +546,27 @@ protected function fold($text)
         }
 
         // split, wrap and trim trailing separator
-        return substr(chunk_split($text, 73, "\r\n "), 0, -3);
+        return substr($this->chunk_split_unicode($text, 73, "\r\n "), 0, -3);
+    }
+
+    /**
+     * multibyte word chunk split
+     * @link http://php.net/manual/en/function.chunk-split.php#107711
+     * 
+     * @param  string  $body     The string to be chunked.
+     * @param  integer $chunklen The chunk length.
+     * @param  string  $end      The line ending sequence.
+     * @return string            Chunked string
+     */
+    protected function chunk_split_unicode($body, $chunklen = 76, $end = "\r\n")
+    {
+        $array = array_chunk(
+            preg_split("//u", $body, -1, PREG_SPLIT_NO_EMPTY), $chunklen);
+        $body = "";
+        foreach ($array as $item) {
+            $body .= join("", $item) . $end;
+        }
+        return $body;
     }
 
     /**
diff --git a/tests/VCardTest.php b/tests/VCardTest.php
index a7415f8..da008c0 100644
--- a/tests/VCardTest.php
+++ b/tests/VCardTest.php
@@ -368,4 +368,23 @@ public function testSpecialFirstNameAndLastName2()
 
         $this->assertEquals('garcon-jeroen', $this->vcard->getFilename());
     }
+
+    public function testChunkSplitUnicode()
+    {
+        $class_handler  = new \ReflectionClass('JeroenDesloovere\VCard\VCard');
+        $method_handler = $class_handler->getMethod('chunk_split_unicode');
+        $method_handler->setAccessible(true);
+
+        $ascii_input="Lorem ipsum dolor sit amet,";
+        $ascii_output = $method_handler->invokeArgs(new VCard(), [$ascii_input,10,'|']);
+        $unicode_input='Τη γλώσσα μου έδωσαν ελληνική το σπίτι φτωχικό στις αμμουδιές του Ομήρου.';
+        $unicode_output = $method_handler->invokeArgs(new VCard(), [$unicode_input,10,'|']);
+
+        $this->assertEquals(
+            "Lorem ipsu|m dolor si|t amet,|",
+            $ascii_output);
+        $this->assertEquals(
+            "Τη γλώσσα |μου έδωσαν| ελληνική |το σπίτι φ|τωχικό στι|ς αμμουδιέ|ς του Ομήρ|ου.|",
+            $unicode_output);
+    }
 }