Extract subscribers to a separate table in the Bounce worker [MAILPOET-940]

lib/Models/ScheduledTaskSubscriber.php

@@ -0,0 +1,61 @@
+<?php
+namespace MailPoet\Models;
+
+if(!defined('ABSPATH')) exit;
+
+class ScheduledTaskSubscriber extends Model {
+  const STATUS_TO_PROCESS = 0;
+  const STATUS_PROCESSED = 1;
+
+  public static $_table = MP_SCHEDULED_TASK_SUBSCRIBERS_TABLE;
+  public static $_id_column = array('task_id', 'subscriber_id');
+
+  static function createOrUpdate($data = array()) {
+    if(!is_array($data) || empty($data['task_id']) || empty($data['subscriber_id'])) return;
+
+    $task_subscriber = self::where('subscriber_id', $data['subscriber_id'])
+      ->where('task_id', $data['task_id'])
+      ->findOne();
+
+    if(empty($task_subscriber)) $task_subscriber = self::create();
+
+    $task_subscriber->task_id = $data['task_id'];
+    $task_subscriber->subscriber_id = $data['subscriber_id'];
+    $task_subscriber->processed = self::STATUS_TO_PROCESS;
+    $task_subscriber->save();
+
+    return $task_subscriber;
+  }
+
+  static function addSubscribers($task_id, array $subscriber_ids) {
+    foreach($subscriber_ids as $subscriber_id) {
+      self::createOrUpdate(array(
+        'task_id' => $task_id,
+        'subscriber_id' => $subscriber_id
+      ));
+    }
+  }
+
+  static function getToProcessCount($task_id) {
+    return self::getCount($task_id, false);
+  }
+
+  static function getProcessedCount($task_id) {
+    return self::getCount($task_id, true);
+  }
+
+  static function getTotalCount($task_id) {
+    return self::getCount($task_id);
+  }
+
+  private static function getCount($task_id, $processed = null) {
+    $orm = self::where('task_id', $task_id);
+    if(!is_null($processed)) {
+      $orm->where(
+        'processed',
+        ($processed) ? self::STATUS_PROCESSED : self::STATUS_TO_PROCESS
+      );
+    }
+    return $orm->count();
+  }
+}