Use Doctrine in WooCommercePastOrders cron worker

[MAILPOET-3814]

lib/Cron/Workers/WooCommercePastOrders.php

@@ -3,8 +3,8 @@
 namespace MailPoet\Cron\Workers;
 
 use MailPoet\Entities\ScheduledTaskEntity;
-use MailPoet\Models\StatisticsClicks;
-use MailPoet\Models\StatisticsWooCommercePurchases;
+use MailPoet\Entities\StatisticsClickEntity;
+use MailPoet\Statistics\StatisticsClicksRepository;
 use MailPoet\Statistics\Track\WooCommercePurchases;
 use MailPoet\WooCommerce\Helper as WCHelper;
 use MailPoetVendor\Carbon\Carbon;
@@ -19,12 +19,17 @@ class WooCommercePastOrders extends SimpleWorker {
   /** @var WooCommercePurchases */
   private $woocommercePurchases;
 
+  /** @var StatisticsClicksRepository */
+  private $statisticsClicksRepository;
+
   public function __construct(
     WCHelper $woocommerceHelper,
+    StatisticsClicksRepository $statisticsClicksRepository,
     WooCommercePurchases $woocommercePurchases
   ) {
     $this->woocommerceHelper = $woocommerceHelper;
     $this->woocommercePurchases = $woocommercePurchases;
+    $this->statisticsClicksRepository = $statisticsClicksRepository;
     parent::__construct();
   }
 
@@ -33,8 +38,8 @@ class WooCommercePastOrders extends SimpleWorker {
   }
 
   public function processTaskStrategy(ScheduledTaskEntity $task, $timer) {
-    $oldestClick = StatisticsClicks::orderByAsc('created_at')->limit(1)->findOne();
-    if (!$oldestClick instanceof StatisticsClicks) {
+    $oldestClick = $this->statisticsClicksRepository->findOneBy([], ['createdAt' => 'asc']);
+    if (!$oldestClick instanceof StatisticsClickEntity) {
       return true;
     }
 
@@ -48,7 +53,7 @@ class WooCommercePastOrders extends SimpleWorker {
 
     $orderIds = $this->woocommerceHelper->wcGetOrders([
       'status' => 'completed',
-      'date_completed' => '>=' . $oldestClick->createdAt,
+      'date_completed' => '>=' . $oldestClick->getCreatedAt()->format('Y-m-d H:i:s'),
       'orderby' => 'ID',
       'order' => 'ASC',
       'limit' => self::BATCH_SIZE,