/**
 * - WHY A PRACTICE IS NOT GOING TO SEE THIS PATIENT.
 *
 * Spencer ruled (b) on 2026-08-24: the coordinator closes an unservable referral with a reason, and
 * the SENDING practice sees that reason. The argument is about the patient rather than tidiness -
 * *"they declined"* and *"we sent it to the wrong place"* lead the sender to do completely different
 * things for somebody who still needs care.
 *
 * A FIXED LIST, AND THE CODES MUST MATCH THE SERVER'S EXACTLY. This value crosses an organization
 * boundary: written here, read by the practice that sent the referral. Free text is a disclosure
 * surface and *"declined because..."* is arguably clinical - far easier to add later than to take back.
 * `utils/referralClosureReason.ts` in the api repo is the other half; the server refuses anything
 * off this list, so a drift here is a 400 rather than a silent wrong value.
 */

export const REFERRAL_CLOSURE_REASONS = {
    DECLINED_BY_PATIENT: 'declined-by-patient',
    DUPLICATE: 'duplicate',
    NOT_A_SERVICE_WE_OFFER: 'not-a-service-we-offer',
    UNABLE_TO_REACH_PATIENT: 'unable-to-reach-patient',
} as const;

export type ReferralClosureReason =
    (typeof REFERRAL_CLOSURE_REASONS)[keyof typeof REFERRAL_CLOSURE_REASONS];

/**
 * What a coordinator picks from, in the words they would use.
 *
 * ORDERED BY HOW OFTEN A FRONT DESK WILL REACH FOR IT, not alphabetically - "could not reach them" and
 * "they declined" are the everyday outcomes; a duplicate or a wrong-specialty referral is rarer.
 * THE LABEL IS OURS AND THE CODE IS THE CONTRACT. Rewording a label is safe; changing a code is a
 * cross-organization vocabulary change and needs the server in the same commit.
 */
export const REFERRAL_CLOSURE_REASON_LABELS: Record<ReferralClosureReason, string> = {
    [REFERRAL_CLOSURE_REASONS.UNABLE_TO_REACH_PATIENT]: 'We could not reach the patient',
    [REFERRAL_CLOSURE_REASONS.DECLINED_BY_PATIENT]: 'The patient declined',
    [REFERRAL_CLOSURE_REASONS.NOT_A_SERVICE_WE_OFFER]: 'Not a service we offer',
    [REFERRAL_CLOSURE_REASONS.DUPLICATE]: 'Duplicate of another referral',
};

/**
 * The order the choices are offered in.
 *
 * Derived from the label map rather than written twice - a second list is one that silently loses an
 * option the day somebody adds one.
 */
export const REFERRAL_CLOSURE_REASON_CHOICES = Object.keys(
    REFERRAL_CLOSURE_REASON_LABELS,
) as ReferralClosureReason[];

/**
 * What the SENDING practice reads on a closed referral.
 *
 * Falls back to the raw code rather than to "Closed" or an empty string: an unrecognised code means
 * the other side is running a newer vocabulary than we are, and showing the code is honest and still
 * actionable. Swallowing it would tell a sender the referral ended for no reason.
 */
export const referralClosureReasonLabel = (reason?: string): string | undefined => {
    if (!reason) return undefined;

    return REFERRAL_CLOSURE_REASON_LABELS[reason as ReferralClosureReason] ?? reason;
};