Pagination active pages resolver

getActivePages.js

const getActivePages = ({ activePage = 1, pageListLength, pages }) => {
    const pageCount = pages < pageListLength ? pages : pageListLength;
    const array = Array.from({ length: pageCount });
    const middle = Math.ceil(pageCount / 2);

    // When the page number is less than the median of the displayed pages, show first n pages
    if (activePage < middle) {
      return array.map((_, index) => index + 1);
    }

    // When the page number is more than the median of the displayed pages, show last n pages
    if (pages - activePage < middle) {
      return array.map((_, index) => pages - index).reverse();
    }

    // Otherwise show page numbers centered around activePage
    return array.map(
      (_, index) => index + activePage - middle + (pageCount % 2) + 1,
    );
  };