import { setUrlParams } from '~/lib/utils/url_utility';
import { createAlert } from '~/flash';
import { __ } from '~/locale';

export default function redirectToCorrectBlamePage() {
  const { hash } = window.location;
  const linesPerPage = parseInt(document.querySelector('.js-per-page').dataset.perPage, 10);
  const params = new URLSearchParams(window.location.search);
  const currentPage = parseInt(params.get('page'), 10);
  const isPaginationDisabled = params.get('no_pagination');
  if (hash && linesPerPage && !isPaginationDisabled) {
    const lineNumber = parseInt(hash.split('#L')[1], 10);
    const pageToRedirect = Math.ceil(lineNumber / linesPerPage);
    const isRedirectNeeded =
      (pageToRedirect > 1 && pageToRedirect !== currentPage) || pageToRedirect < currentPage;
    if (isRedirectNeeded) {
      createAlert({
        message: __('Please wait a few moments while we load the file history for this line.'),
      });
      window.location.href = setUrlParams({ page: pageToRedirect });
    }
  }
}