file-commons/src/formatFileSize.ts

import numeral from 'numeral'

type FormatFileSize = (maybeNumber: unknown) => string

const formatFileSize: FormatFileSize = maybeNumber => {
  if (typeof maybeNumber! !== 'number') {
    throw TypeError('Argument should be a number.')
  }

  const n = maybeNumber as number
  if (isNaN(n)) {
    throw RangeError('Cannot format NaN.')
  }

  const base = numeral(Math.abs(n)).format(Math.abs(n) < 1000 ? '0 b' : '0.00 b')

  return `${n < 0 ? '-' : ''}${base}`
}

export default formatFileSize