(a) A court may stay an arbitration commenced or threatened on application and a showing that there is not an agreement to arbitrate.
(b) If there is a substantial bona fide dispute as to whether an agreement to arbitrate exists, the court shall try the issue promptly and summarily.
(c) The court shall stay the arbitration if the court finds for the party moving for the stay. If the court finds for the party opposing the stay, the court shall order the parties to arbitrate.