displayName.js

/*
 * CJK Regex brought from http://apps.timwhitlock.info/js/regex
 */

var CJKRegex = /[⺀-\u2efe\u3000-〾\u3040-ゞ゠-ヾ㇀-\u31eeㇰ-ㇾ㈀-㋾㌀-㏾㐀-\u4dbe一-\u9ffe豈-\ufafe︰-﹎]|[\ud840-\ud868\ud86a-\ud86c][\udc00-\udfff]|\ud82c[\udc00-\udcfe]|\ud869[\udc00-\udede\udf00-\udfff]|\ud86d[\udc00-\udf3e\udf40-\udfff]|\ud86e[\udc00-\udc1e]|\ud87e[\udc00-\ude1e]/;

/*
 * Normalize display name for both Chinese and English names.
 * @function
 * @param {string} firstName
 * @param {string} lastName
 * @returns {string}
 */
function displayName (firstName, lastName) {
  var endOfFirst = firstName[firstName.length - 1],
    beginOfLast = lastName[0];

  if (CJKRegex.test(endOfFirst)) {
    if (CJKRegex.test(beginOfLast)) {
      return lastName + firstName;
    } else {
      return firstName + lastName;
    }
  } else {
    if (CJKRegex.test(beginOfLast)) {
      return lastName + firstName;
    } else {
      return firstName + ' ' + lastName;
    }
  }
}