class QueueTest

class QueueTest extends DrupalUnitTestBase {

  /**
   * The modules to enable.
   *
   * @var array
   */
  public static $modules = array(
    'system',
  );
  public static function getInfo() {
    return array(
      'name' => 'Queue functionality',
      'description' => 'Queues and dequeues a set of items to check the basic queue functionality.',
      'group' => 'Queue',
    );
  }

  /**
   * Tests the System queue.
   */
  public function testSystemQueue() {
    $this
      ->installSchema('system', 'queue');

    // Create two queues.
    $queue1 = new DatabaseQueue($this
      ->randomName(), Database::getConnection());
    $queue1
      ->createQueue();
    $queue2 = new DatabaseQueue($this
      ->randomName(), Database::getConnection());
    $queue2
      ->createQueue();
    $this
      ->queueTest($queue1, $queue2);
  }

  /**
   * Tests the Memory queue.
   */
  public function testMemoryQueue() {

    // Create two queues.
    $queue1 = new Memory($this
      ->randomName());
    $queue1
      ->createQueue();
    $queue2 = new Memory($this
      ->randomName());
    $queue2
      ->createQueue();
    $this
      ->queueTest($queue1, $queue2);
  }

  /**
   * Queues and dequeues a set of items to check the basic queue functionality.
   *
   * @param Drupal\Core\Queue\QueueInterface $queue1
   *   An instantiated queue object.
   * @param Drupal\Core\Queue\QueueInterface $queue2
   *   An instantiated queue object.
   */
  protected function queueTest($queue1, $queue2) {

    // Create four items.
    $data = array();
    for ($i = 0; $i < 4; $i++) {
      $data[] = array(
        $this
          ->randomName() => $this
          ->randomName(),
      );
    }

    // Queue items 1 and 2 in the queue1.
    $queue1
      ->createItem($data[0]);
    $queue1
      ->createItem($data[1]);

    // Retrieve two items from queue1.
    $items = array();
    $new_items = array();
    $items[] = $item = $queue1
      ->claimItem();
    $new_items[] = $item->data;
    $items[] = $item = $queue1
      ->claimItem();
    $new_items[] = $item->data;

    // First two dequeued items should match the first two items we queued.
    $this
      ->assertEqual($this
      ->queueScore($data, $new_items), 2, 'Two items matched');

    // Add two more items.
    $queue1
      ->createItem($data[2]);
    $queue1
      ->createItem($data[3]);
    $this
      ->assertTrue($queue1
      ->numberOfItems(), 'Queue 1 is not empty after adding items.');
    $this
      ->assertFalse($queue2
      ->numberOfItems(), 'Queue 2 is empty while Queue 1 has items');
    $items[] = $item = $queue1
      ->claimItem();
    $new_items[] = $item->data;
    $items[] = $item = $queue1
      ->claimItem();
    $new_items[] = $item->data;

    // All dequeued items should match the items we queued exactly once,
    // therefore the score must be exactly 4.
    $this
      ->assertEqual($this
      ->queueScore($data, $new_items), 4, 'Four items matched');

    // There should be no duplicate items.
    $this
      ->assertEqual($this
      ->queueScore($new_items, $new_items), 4, 'Four items matched');

    // Delete all items from queue1.
    foreach ($items as $item) {
      $queue1
        ->deleteItem($item);
    }

    // Check that both queues are empty.
    $this
      ->assertFalse($queue1
      ->numberOfItems(), 'Queue 1 is empty');
    $this
      ->assertFalse($queue2
      ->numberOfItems(), 'Queue 2 is empty');
  }

  /**
   * Returns the number of equal items in two arrays.
   */
  protected function queueScore($items, $new_items) {
    $score = 0;
    foreach ($items as $item) {
      foreach ($new_items as $new_item) {
        if ($item === $new_item) {
          $score++;
        }
      }
    }
    return $score;
  }

}