public function add($client)
 {
     if ($client->getIdCompte() != null) {
         $idCompte = $client->getIdCompte();
     } else {
         $compte = new Compte(array('solde' => 0));
         $compteManager = new CompteManager($this->db);
         $idCompte = $compteManager->add($compte);
     }
     $date = getEnglishDate($client->getDate_naissance());
     $sql = 'INSERT INTO client(idCompte, nom, prenom, mail, date_naissance, login, pwd) VALUES (:idCompte, :nom, :prenom, :mail, :date_naissance, :login, :pwd)';
     $requete = $this->db->prepare($sql);
     $requete->bindValue(':idCompte', $idCompte);
     $requete->bindValue(':nom', $client->getNom());
     $requete->bindValue(':prenom', $client->getPrenom());
     $requete->bindValue(':mail', $client->getMail());
     $requete->bindValue(':date_naissance', $date);
     $requete->bindValue(':login', $client->getLogin());
     $requete->bindValue(':pwd', $client->getPwd());
     $retour = $requete->execute();
     $idInserted = $this->db->lastInsertId();
     $response = array('idClient' => $idInserted, 'idCompte' => $idCompte, 'ajoutClient' => $retour);
     return json_encode($response);
 }