import type { Appointment } from 'fhir/r4';
import { ORGANIZATION_TAG_SYSTEM } from './carePlanAuthorship';

// The statuses the server cancels when a patient withdraws a grant (cancelAppointment.ts).
const CANCELLED_ON_WITHDRAWAL: ReadonlySet<string> = new Set([
    'proposed', 'pending', 'booked', 'arrived', 'checked-in', 'waitlist',
]);

/**
 * The visits a withdrawal from this practice will cancel, by the server's own rule: tagged with this
 * practice, still standing, and starting after the instant. A visit with no start is left alone there,
 * so it is not counted here.
 */
export const visitsAWithdrawalCancels = (
    appointments: readonly Appointment[],
    organizationId: string,
    now: string,
): Appointment[] => appointments.filter((appointment) =>
    appointment.meta?.tag?.some((tag) => tag.system === ORGANIZATION_TAG_SYSTEM && tag.code === organizationId)
    && CANCELLED_ON_WITHDRAWAL.has(appointment.status ?? '')
    && Boolean(appointment.start)
    && Date.parse(appointment.start as string) > Date.parse(now))
    .sort((a, b) => Date.parse(a.start as string) - Date.parse(b.start as string));

/** What the visit is, falling back to the plain word so a listed visit is never nameless. */
export const withdrawnVisitName = (appointment: Appointment): string =>
    appointment.serviceType?.[0]?.text?.trim()
    || appointment.serviceType?.[0]?.coding?.find((coding) => coding.display?.trim())?.display?.trim()
    || appointment.appointmentType?.text?.trim()
    || appointment.description?.trim()
    || 'Visit';