/**
 * Hook of List UI state manager
 * - filter
 * - pagination
 * - sort
 *
 * @flow
 */
export const useFunctionalList = ({ items, filterableColumns }) => {
  const [listOpts, setListOpts] = React.useState({
    page: 1,
    per: 10,
    query: '',
    sortBy: null,
    sortDirection: ''
  });
  const handleChangeFilter = (query: string) =>
    setListOpts(s => ({ ...s, page: 1, query }));
  const handleChangeSort = (sortBy: string, sortDirection: 'ASC' | 'DESC') =>
    setListOpts(s => ({ ...s, sortBy, sortDirection }));
  const handleChangePage = (page: number) => setListOpts(s => ({ ...s, page }));
  const handleChangePer = (per: number) =>
    setListOpts(s => ({ ...s, page: 1, per }));

  const filteredItems = items.filter(row =>
    filterableColumns.some(propName =>
      (row[propName] || '').includes(listOpts.query)
    )
  );
  const sortSign = listOpts.sortDirection === 'ASC' ? 1 : -1;
  const showingItems = filteredItems
    .sort((a, b) => {
      if (listOpts.sortBy == null) return 0;
      const av = a[listOpts.sortBy];
      const bv = b[listOpts.sortBy];
      return av === bv ? 0 : (av > bv ? 1 : -1) * sortSign;
    })
    .slice(listOpts.per * (listOpts.page - 1), listOpts.per * listOpts.page);

  return {
    filteredItems,
    handleChangeFilter,
    handleChangePage,
    handleChangePer,
    handleChangeSort,
    listOpts,
    showingItems
  };
};