import type { Patient } from 'fhir/r4';

export type BookingPatientSeed = { patient: Patient; from: 'chart' | 'open-visit' };

/**
 * The patient a new booking starts on, and why.
 *
 * - A chart's Book Appointment names its patient explicitly, so that patient starts picked (deck
 *   practitioner#s-appointments "Booking"). It wins over a visit open on someone else, because the
 *   chart is what the practitioner pressed the button on.
 * - With no chart, the open visit's own patient, as before.
 * - With neither, nobody: a wrong guess is a booking on the wrong record.
 */
export const bookingPatientSeed = (
    chartPatient: Patient | undefined,
    openVisitPatient: Patient | undefined,
): BookingPatientSeed | undefined => {
    if (chartPatient) return { patient: chartPatient, from: 'chart' };
    if (openVisitPatient) return { patient: openVisitPatient, from: 'open-visit' };
    return undefined;
};