keycloak-scim/js/apps/admin-ui/src/utils/useLocaleSort.ts

import { useWhoAmI } from "../context/whoami/WhoAmI";

export type ValueMapperFn<T> = (item: T) => string | undefined;

export default function useLocaleSort() {
  const { whoAmI } = useWhoAmI();

  return function localeSort<T>(items: T[], mapperFn: ValueMapperFn<T>): T[] {
    const locale = whoAmI.getLocale();

    return [...items].sort((a, b) => {
      const valA = mapperFn(a);
      const valB = mapperFn(b);

      if (valA === undefined || valB === undefined) {
        return 0;
      }

      return valA.localeCompare(valB, locale);
    });
  };
}

// TODO: This might be built into TypeScript into future.
// See: https://github.com/microsoft/TypeScript/issues/48992
type KeysMatching<T, V> = {
  [K in keyof T]: T[K] extends V ? K : never;
}[keyof T];

export const mapByKey =
  <
    T extends { [_ in K]?: string },
    K extends KeysMatching<T, string | undefined>,
  >(
    key: K,
  ) =>
  (item: T) =>
    item[key];