"use strict";

const ENV_PERF = require("../env/preferPerf");

const FROZEN_ARRAY = require("../native/EMPTY_ARRAY");

const MAX_ARRAY_LENGTH = require("../native/MAX_ARRAY_LENGTH");

const stringToArray = require("../cast/stringToArray");

const castSlice = require("../fp/slice");

const isString = require("../is/stringPrimitive");

const isRegExp = require("../is/regexp");

const isUndefined = require("../is/undefined");

const isNill = require("../is/nullOrUndefined");

const hasUnicode = require("./hasUnicode");
/**
 * Splits `string` by `separator`.
 * @symb 🤸
 *
 * @NOTE This method is based on
 * [`String#split`](https://mdn.io/String/split).
 *
 * @curried 2
 * @since 4.0.0
 * @category String
 *
 *
 * @param {string} [string=''] The string to split.
 * @param {RegExp|string} separator The separator pattern to split by.
 * @param {number} [limitArg] The length to truncate results to.
 * @return {Array} Returns the string segments.
 *
 * @see http://speakingjs.com/es5/ch24.html
 *
 * @example
 *
 *   split('a-b-c', '-', 2)
 *   //=> ['a', 'b']
 *
 */


function split(string, separator, limitArg) {
  const limit = isUndefined(limitArg) ? MAX_ARRAY_LENGTH : limitArg >>> 0; // @TODO EMPTY_ARRAY?

  if (!limit) {
    return ENV_PERF ? FROZEN_ARRAY : [];
  } // split the unicode string into an array, then slice it


  if (string && ( // isString, or nill && !regexp
  isString(separator) || isNill(separator) && !isRegExp(separator))) {
    if (!separator && hasUnicode(string)) {
      return castSlice(stringToArray(string), 0, limit);
    }
  } // normal...


  return string.split(separator, limit);
}

module.exports = split;