department-of-veterans-affairs/vets-website

import { ROUTES } from '../constants';
import { RESPONSES, SHORT_NAME_MAP } from '../constants/question-data-map';
import { BATCH_MAP } from '../constants/question-batches';

/** ================================================================
 * Find batch (category) for question SHORT_NAME
 */
export const getQuestionBatch = shortName => {
  for (const batch of Object.keys(BATCH_MAP)) {
    if (BATCH_MAP[batch]?.includes(shortName)) {
      return batch;
    }
  }

  return null;
};

/** ================================================================
 * Filter object for a given value (predicate true/false function)
 */
Object.filter = (obj, predicate) =>
  Object.keys(obj)
    .filter(key => predicate(obj[key]))
    .reduce((res, key) => Object.assign(res, { [key]: obj[key] }), {});

export const printErrorMessage = message =>
  // eslint-disable-next-line no-console
  console.error(message);

/** ================================================================
 * Move to given route or error if route not found
 * @param {number} shortName - question to route to
 */
export const pushToRoute = (shortName, router) => {
  const newRoute = ROUTES?.[shortName];

  if (newRoute) {
    router.push(newRoute);
  } else {
    printErrorMessage('Unable to determine page to display');
  }
};

/** ================================================================
 * Return SHORT_NAMEs with answers in the store
 *
 * @param {object} responsesToClean - all answers in the store
 */
export const getNonNullShortNamesFromStore = responsesToClean => {
  const nonNullResponses = Object.filter(
    responsesToClean,
    response => response !== null,
  );

  return Object.keys(nonNullResponses);
};

/** ================================================================
 * Determine the last question answered before a results page
 * so the results page knows quickly where to go back to if "Back" is used
 */
export const getLastQuestionAnswered = formResponses => {
  const nonNullShortNames = getNonNullShortNamesFromStore(formResponses);

  return nonNullShortNames?.reverse()?.[0];
};

/** ================================================================
 * Used for results pages
 * When the Back button is clicked, find the last question that was answered
 * in the flow based on service period response and direct user back there
 * @param {object} formResponses - all answers in the store
 */
export const onResultsBackClick = (formResponses, router) => {
  const previousQuestion = getLastQuestionAnswered(formResponses);

  return pushToRoute(previousQuestion, router);
};

/** ================================================================
 * Get the SERVICE_PERIOD response from the formResponses
 *
 * @param {object} formResponses - all answers in the store
 */
export const getServicePeriodResponse = formResponses =>
  formResponses?.[SHORT_NAME_MAP.SERVICE_PERIOD];

/** ================================================================
 * Removes all answers in the store that are not "Yes"
 *
 * @param {object} formResponses - all answers in the store
 */
export const filterForYesResponses = formResponses => {
  return Object.keys(
    Object.filter(formResponses, response => response === RESPONSES.YES),
  );
};