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

/** What an appointment read asked for; a held appointment shows only on the reads whose query it meets. */
export type AppointmentQuery = {
    patientId?: string;
    organizationId?: string;
    start?: string;
    end?: string;
    statuses?: readonly string[];
    actors?: readonly string[];
};

// A date-only upper bound covers that whole day, as the search does.
const boundAt = (bound: string, upper: boolean): number =>
    Date.parse(bound) + (upper && /^\d{4}-\d{2}-\d{2}$/.test(bound) ? 86_400_000 - 1 : 0);

export const appointmentInQuery = (appointment: Appointment, query: AppointmentQuery): boolean => {
    if (query.patientId !== undefined && appointmentPatientId(appointment) !== query.patientId) return false;
    if (query.organizationId) {
        const practice = appointment.meta?.tag?.find((tag) => tag.system === ORGANIZATION_TAG_SYSTEM)?.code;
        if (practice !== query.organizationId) return false;
    }
    if (query.statuses?.length && !query.statuses.includes(appointment.status)) return false;
    if (query.actors && !(appointment.participant ?? []).some((participant) =>
        participant.actor?.reference !== undefined && query.actors?.includes(participant.actor.reference))) return false;
    if (query.start || query.end) {
        const at = Date.parse(appointment.start ?? '');
        if (!Number.isFinite(at)) return false;
        if (query.start && at < boundAt(query.start, false)) return false;
        if (query.end && at > boundAt(query.end, true)) return false;
    }
    return true;
};