/**
 * Truncates a string to the given number of chars (maxLength) by inserting '...' in the middle of that string.
 * Partially taken from https://stackoverflow.com/a/5723274/3192470.
 *
 * @param {string} string - string to be truncated
 * @param {number} maxLength - maximum size of the resulting string
 * @returns {string}
 */
export default function truncateString(string, maxLength) {
  if (typeof string !== 'string') {
    return '';
  }
  var separator = '...';

  // Return original string if it's already shorter than maxLength
  if (string.length <= maxLength) {
    return string;
    // Return truncated substring without '...' if string can't be meaningfully truncated
  } else if (maxLength <= separator.length) {
    return string.substr(0, maxLength);
    // Return truncated string divided in half by '...'
  } else {
    var charsToShow = maxLength - separator.length;
    var frontChars = Math.ceil(charsToShow / 2);
    var backChars = Math.floor(charsToShow / 2);
    return string.substr(0, frontChars) + separator + string.substr(string.length - backChars);
  }
}