// generateCombinations.js
/*global adventurejs A*/

/**
 * Generate string combinations from an array of substrings.
 * @method adventurejs#generateCombinations
 * @memberOf adventurejs
 * @param {Object} world
 */
adventurejs.generateCombinations = function Adventurejs_generateCombinations(
  arrays
) {
  function combine(prefix, arrays, index, result) {
    if (index === arrays.length) {
      result.push(prefix.join(", "));
      return;
    }
    for (let item of arrays[index]) {
      combine([...prefix, item], arrays, index + 1, result);
    }
  }
  const result = [];
  combine([], arrays, 0, result);
  return result;
};