Add getOrdersCount() to WooCommerce helper

[MAILPOET-1732]

lib/WooCommerce/Helper.php

@@ -1,7 +1,20 @@
 <?php
 namespace MailPoet\WooCommerce;
 
+use MailPoet\WP\Functions;
+
 class Helper {
+
+  /** @var Functions */
+  private $wp;
+
+  function __construct(Functions $wp = null) {
+    if (!$wp) {
+      $wp = Functions::get();
+    }
+    $this->wp = $wp;
+  }
+
   function isWooCommerceActive() {
     return class_exists('WooCommerce');
   }
@@ -21,4 +34,11 @@ class Helper {
   function wcGetProduct($the_product = false) {
     return wc_get_product($the_product);
   }
+
+  function getOrdersCount() {
+    $counts = $this->wp->wpCountPosts('shop_order');
+    return array_reduce((array)$counts, function($sum, $count_for_state) {
+      return $sum + (int)$count_for_state;
+    });
+  }
 }