import { AssessorApiClient } from '../../api/assessor-api-client';
import { readEnginePreferences, subscribeEnginePreferences } from '../../app/engine-preferences';

let unlink: (() => void) | undefined;

/**
 * Switching the Compliance Engine off also switches off the server-side automatic ISO mapping, in whichever
 * view the Engines popup is used. Switching it on again leaves automatic mapping off until the Data Hub
 * switch is used. Batches that already started are not cancelled.
 */
export function linkAutoMappingToEngineSwitch(api: Pick<AssessorApiClient, 'setIsoAutoMapping'> = new AssessorApiClient()): () => void {
  unlink?.();
  let active = readEnginePreferences().compliance;
  const unsubscribe = subscribeEnginePreferences(() => {
    const next = readEnginePreferences().compliance;
    if (active && !next) void Promise.resolve().then(() => api.setIsoAutoMapping(false)).catch(() => undefined);
    active = next;
  });
  unlink = () => { unsubscribe(); unlink = undefined; };
  return unlink;
}