/**
  * Get artifacts that responds to some criteria
  *
  * @param date    $date      The date criteria
  * @param Integer $trackerId The Tracker Id
  *
  * @return Array
  */
 public function getArtifactsByCriterias($date, $trackerId = null)
 {
     $artifacts = array();
     $dao = new Tracker_ArtifactDao();
     $dar = $dao->getArtifactsBySubmittedOnDate($trackerId, $date);
     if ($dar && !$dar->isError()) {
         $artifactFactory = Tracker_ArtifactFactory::instance();
         foreach ($dar as $row) {
             $artifacts[] = $artifactFactory->getArtifactById($row['artifact_id']);
         }
     }
     return $artifacts;
 }