classNames.js

import cx from 'classnames';

const defaultPrefix = 'ais';

let classMapper = className => className;

const defaultFormatter = (block, elements) => ({
  className: cx(
    elements
      .filter(element => element !== undefined && element !== false)
      .map(element => `${prefix}-${block}__${element}`)
      .map(classMap)
  ),
});

let prefix = defaultPrefix;

let formatter = defaultFormatter;

export function setPrefix(newPrefix) {
	prefix = newPrefix;
}

export function setFormatter(newFormatter) {
	formatter = newFormatter;
}

export function setClassMapper(newClassMapper) {
	classMapper = newClassMapper;
}

export default function classNames(block) {
  return (...elements) => formatter(block, elements);
}