/**
 * WHAT THE REVIEW STEP AND THE RECEIPT CALL THE VISIT.
 *
 * MEASURED 2026-09-15, booking as a patient at a practice that requires a new patient consultation
 * first. Two steps earlier the flow had locked the care type itself and said why - "New patient
 * consultation, required for your first visit with this practice" - and then the review step, and the
 * receipt after it, both read **"Service : Not specified"**. The patient's home card and the
 * appointment's own detail screen named it correctly, so the value was never missing: the review step
 * asked two sources and the answer was in a third.
 *
 * WHY IT MATTERS MORE THAN THE WORDING. The review step is the last thing a patient sees before the
 * write, and its whole job is letting them check what they are about to book. Telling them the service
 * is unspecified, on a flow that had just told them a specific one was required, is two answers to one
 * question on the screen asking them to confirm - and the receipt is the artifact they keep.
 *
 * THE ORDER IS MOST SPECIFIC FIRST: the block the booking is actually filed against, then what the
 * patient chose, then what the flow chose for them. The third is the one that was missing.
 */

export const SERVICE_NOT_STATED = 'Not specified';

export const reviewServiceLabel = (
    onTheBlock: string | undefined,
    chosenByThePatient: string | undefined,
    pinnedByTheFlow: string | undefined,
): string => {
    const named = [onTheBlock, chosenByThePatient, pinnedByTheFlow]
        .map((candidate) => candidate?.trim())
        .find((candidate) => Boolean(candidate));

    // Still a last resort rather than an empty gap: a blank where the service goes reads as a service
    // with no name, and this at least says the screen does not know.
    return named ?? SERVICE_NOT_STATED;
};