- Refactors sending queue worker by breaking it into smaller tasks

- Adds arrayUnique method to Helpers for multidimensional arrays

lib/Cron/Workers/SendingQueue/Tasks/Links.php

@@ -0,0 +1,33 @@
+<?php
+namespace MailPoet\Cron\Workers\SendingQueue\Tasks;
+
+use MailPoet\Newsletter\Links\Links as NewsletterLinks;
+use MailPoet\Util\Helpers;
+
+if(!defined('ABSPATH')) exit;
+
+class Links {
+  static function process(array $newsletter, array $queue) {
+    list($newsletter, $links) = self::hashAndReplaceLinks($newsletter, $queue);
+    self::saveLinks($links, $newsletter, $queue);
+    return $newsletter;
+  }
+
+  static function hashAndReplaceLinks(array $newsletter, array $queue) {
+    // join HTML and TEXT rendered body into a text string
+    $content = Helpers::joinObject($newsletter['rendered_body']);
+    list($content, $links) = NewsletterLinks::process($content);
+    // split the processed body with hashed links back to HTML and TEXT
+    list($newsletter['rendered_body']['html'], $newsletter['rendered_body']['text'])
+      = Helpers::splitObject($content);
+    return array(
+      $newsletter,
+      $links
+    );
+  }
+
+  static function saveLinks($links, $newsletter, $queue) {
+    return NewsletterLinks::save($links, $newsletter['id'], $queue['id']);
+  }
+}
+