breakpoints.js

exports.createBreakpointsApi = ({ breakpoints }) => {
  const breakpointsObject = Object(breakpoints);
  const keys = Object.keys(breakpointsObject);
  const indexMap = {};
  keys.forEach((key, index) => {
    indexMap[key] = index;
  });

  const up = (min) => breakpointsObject[min];

  const down = (max) => calcMaxWidth(breakpointsObject[max]);

  const getNextKey = (key) => {
    const currentIndex = indexMap[key];
    return currentIndex < keys.length - 1 ? keys[currentIndex + 1] : undefined;
  };

  const between = (min, max) => ({
    min: up(min),
    max: down(max),
  });

  const only = (key) =>
    key === keys[keys.length - 1] ? up(key) : between(key, getNextKey(key));

  return {
    keys,
    getNextKey,
    up,
    down,
    between,
    only,
  };
};