/**
 * - A BLOCK WHOSE ONLY PLACE IS THE VIRTUAL ONE IS A MODALITY, NOT A SITE.
 *
 * Telehealth is a Location on this project, so a diary block offered only at the org's virtual
 * Location can be booked one way and one way only: by video. Choosing that block IS choosing video,
 * before the Location control is ever touched.
 *
 * WHY THIS MATTERS AT THE PICKER. The server gates a video booking three ways - the practice offers
 * video, the block offers it, and the service is marked deliverable by video (default not) - and the
 * third is the one the front desk met as a refusal at the end of a filled-in form:
 *
 *     ERROR: This service cannot be delivered by video. Please book it in person, or contact the practice.
 *
 * Measured at the desk on 2026-09-13: the picker offered exactly one practitioner for a follow-up
 * consultation, "Dr. Practitioner One - Video Visit", and it was the one option that could never be
 * booked. The gate is correct and load-bearing; the list was not applying it.
 *
 * `every` rather than `includes`: a block offered at a site AND by video is a real choice between the
 * two, and the Location control is where that choice is made. This names only the block that leaves
 * no choice at all. An empty list is not video-only either - that is a role scoped to every site.
 */
export const blockIsVideoOnly = (
    locationIds: readonly (string | undefined)[],
    virtualLocationId: string | undefined,
): boolean =>
    !!virtualLocationId &&
    locationIds.length > 0 &&
    locationIds.every((id) => id === virtualLocationId);

/**
 * The server's own two sentences, on the row instead of after the booking.
 *
 * Kept as the reason a row is disabled rather than as a refusal, because the rule they state is the
 * practice's configuration and not a fault: a receptionist reading either one knows what to change,
 * or knows to book the visit in person.
 */
export const VIDEO_ONLY_SERVICE_INELIGIBLE = 'this service cannot be delivered by video';
export const VIDEO_ONLY_PRACTICE_DISABLED = 'this practice does not offer video visits';