import type { Encounter, Reference } from 'fhir/r4';
import {
    useEncounterServiceContext,
    useFhirServiceContext,
    usePatientServiceContext,
} from '../services';
import { activeEncounterDefault } from '../utils/activeEncounterDefault';

/**
 * The visit to file a clinical record against when it is being recorded from inside one.
 *
 * Every encounter-aware clinical form needs the same three context reads to build one reference, and
 * eight of them were each going to grow their own copy. The rule itself lives in
 * `activeEncounterDefault`, so it stays testable without React; this is only the wiring.
 *
 * Undefined outside a visit, which is what makes the chart route open its picker empty.
 */
export const useActiveEncounterReference = (): Reference | undefined => {
    const { encounterState } = usePatientServiceContext();
    const { createReferenceObject } = useFhirServiceContext();
    const { getEncounterDisplay } = useEncounterServiceContext();

    return activeEncounterDefault(encounterState, (id) =>
        createReferenceObject('Encounter', id, getEncounterDisplay(encounterState as Encounter)));
};