@graffy/common/esm/decorate/rangeToPage.js

Common libraries that used by various Graffy modules.

import { keyStep } from '../graph';
import { decodeKey } from '../encode';
export default function rangeToPage(key, end, count) {
  const page = {};
  if (typeof count === 'number') page[count > 0 ? 'first' : 'last'] = count;

  if (key !== '') {
    const {
      key: k,
      step
    } = keyStep(key);
    page.after = decodeKey(k);
    if (step === 1) page.excludeAfter = true;
  }

  if (end !== '\uffff') {
    const {
      key: k,
      step
    } = keyStep(end);
    page.before = decodeKey(k);
    if (step === -1) page.excludeBefore = true;
  }

  return page;
}