(1) This rule applies if—(a) the defendant makes an offer that is not accepted by the plaintiff; and(b) the plaintiff’s proceeding is dismissed; and(c) the court is satisfied that the defendant was at all material times willing and able to carry out what was proposed in the offer.
(2) Unless a party shows another order for costs is appropriate in the circumstances, the court must order the plaintiff to pay the defendant’s costs—(a) calculated on the standard basis, up to and including the day of service of the offer; and(b) calculated on the indemnity basis, after the day of service of the offer.