/** * Given the number of pages to display, the current page and the total pages, * returns the min and max index of the pages to display in the pagination component. * * @param {integer} pagesToDisplay Maximum number of pages to display in the pagination component. * @param {integer} currentPage Page currently visible. * @param {integer} totalPages Total pages available. * @return {object} Object containing the min and max index to display in the pagination component. */ export const getIndexes = ( pagesToDisplay, currentPage, totalPages ) => { const extraPagesToDisplay = pagesToDisplay - 1; const tentativeMinIndex = Math.max( Math.floor( currentPage - extraPagesToDisplay / 2 ), 1 ); const maxIndex = Math.min( Math.ceil( currentPage + ( extraPagesToDisplay - ( currentPage - tentativeMinIndex ) ) ), totalPages ); const minIndex = Math.max( Math.floor( currentPage - ( extraPagesToDisplay - ( maxIndex - currentPage ) ) ), 1 ); return { minIndex, maxIndex }; };