/*!
 * pascalcase <https://github.com/jonschlinkert/pascalcase>
 *
 * Copyright (c) 2015, Jon Schlinkert.
 * Licensed under the MIT License.
 */

function pascalcase(str) {
  if (typeof str !== 'string') {
    throw new TypeError('expected a string.');
  }
  str = str.replace(/([A-Z])/g, ' $1');
  if (str.length === 1) { return str.toUpperCase(); }
  str = str.replace(/^[\W_]+|[\W_]+$/g, '').toLowerCase();
  str = str.charAt(0).toUpperCase() + str.slice(1);
  return str.replace(/[\W_]+(\w|$)/g, function (_, ch) {
    return ch.toUpperCase();
  });
}

module.exports = pascalcase;