(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
  typeof define === 'function' && define.amd ? define(factory) :
  (global = global || self, global.i18nextBrowserLanguageDetector = factory());
}(this, (function () { 'use strict';

  function _classCallCheck(instance, Constructor) {
    if (!(instance instanceof Constructor)) {
      throw new TypeError("Cannot call a class as a function");
    }
  }

  function _defineProperties(target, props) {
    for (var i = 0; i < props.length; i++) {
      var descriptor = props[i];
      descriptor.enumerable = descriptor.enumerable || false;
      descriptor.configurable = true;
      if ("value" in descriptor) descriptor.writable = true;
      Object.defineProperty(target, descriptor.key, descriptor);
    }
  }

  function _createClass(Constructor, protoProps, staticProps) {
    if (protoProps) _defineProperties(Constructor.prototype, protoProps);
    if (staticProps) _defineProperties(Constructor, staticProps);
    return Constructor;
  }

  var arr = [];
  var each = arr.forEach;
  var slice = arr.slice;
  function defaults(obj) {
    each.call(slice.call(arguments, 1), function (source) {
      if (source) {
        for (var prop in source) {
          if (obj[prop] === undefined) obj[prop] = source[prop];
        }
      }
    });
    return obj;
  }

  // eslint-disable-next-line no-control-regex
  var fieldContentRegExp = /^[\u0009\u0020-\u007e\u0080-\u00ff]+$/;

  var serializeCookie = function serializeCookie(name, val, options) {
    var opt = options || {};
    opt.path = opt.path || '/';
    var value = encodeURIComponent(val);
    var str = name + '=' + value;

    if (opt.maxAge > 0) {
      var maxAge = opt.maxAge - 0;
      if (isNaN(maxAge)) throw new Error('maxAge should be a Number');
      str += '; Max-Age=' + Math.floor(maxAge);
    }

    if (opt.domain) {
      if (!fieldContentRegExp.test(opt.domain)) {
        throw new TypeError('option domain is invalid');
      }

      str += '; Domain=' + opt.domain;
    }

    if (opt.path) {
      if (!fieldContentRegExp.test(opt.path)) {
        throw new TypeError('option path is invalid');
      }

      str += '; Path=' + opt.path;
    }

    if (opt.expires) {
      if (typeof opt.expires.toUTCString !== 'function') {
        throw new TypeError('option expires is invalid');
      }

      str += '; Expires=' + opt.expires.toUTCString();
    }

    if (opt.httpOnly) str += '; HttpOnly';
    if (opt.secure) str += '; Secure';

    if (opt.sameSite) {
      var sameSite = typeof opt.sameSite === 'string' ? opt.sameSite.toLowerCase() : opt.sameSite;

      switch (sameSite) {
        case true:
          str += '; SameSite=Strict';
          break;

        case 'lax':
          str += '; SameSite=Lax';
          break;

        case 'strict':
          str += '; SameSite=Strict';
          break;

        case 'none':
          str += '; SameSite=None';
          break;

        default:
          throw new TypeError('option sameSite is invalid');
      }
    }

    return str;
  };

  var cookie = {
    create: function create(name, value, minutes, domain) {
      var cookieOptions = arguments.length > 4 && arguments[4] !== undefined ? arguments[4] : {
        path: '/',
        sameSite: 'strict'
      };

      if (minutes) {
        cookieOptions.expires = new Date();
        cookieOptions.expires.setTime(cookieOptions.expires.getTime() + minutes * 60 * 1000);
      }

      if (domain) cookieOptions.domain = domain;
      document.cookie = serializeCookie(name, encodeURIComponent(value), cookieOptions);
    },
    read: function read(name) {
      var nameEQ = name + '=';
      var ca = document.cookie.split(';');

      for (var i = 0; i < ca.length; i++) {
        var c = ca[i];

        while (c.charAt(0) === ' ') {
          c = c.substring(1, c.length);
        }

        if (c.indexOf(nameEQ) === 0) return c.substring(nameEQ.length, c.length);
      }

      return null;
    },
    remove: function remove(name) {
      this.create(name, '', -1);
    }
  };
  var cookie$1 = {
    name: 'cookie',
    lookup: function lookup(options) {
      var found;

      if (options.lookupCookie && typeof document !== 'undefined') {
        var c = cookie.read(options.lookupCookie);
        if (c) found = c;
      }

      return found;
    },
    cacheUserLanguage: function cacheUserLanguage(lng, options) {
      if (options.lookupCookie && typeof document !== 'undefined') {
        cookie.create(options.lookupCookie, lng, options.cookieMinutes, options.cookieDomain, options.cookieOptions);
      }
    }
  };

  var querystring = {
    name: 'querystring',
    lookup: function lookup(options) {
      var found;

      if (typeof window !== 'undefined') {
        var query = window.location.search.substring(1);
        var params = query.split('&');

        for (var i = 0; i < params.length; i++) {
          var pos = params[i].indexOf('=');

          if (pos > 0) {
            var key = params[i].substring(0, pos);

            if (key === options.lookupQuerystring) {
              found = params[i].substring(pos + 1);
            }
          }
        }
      }

      return found;
    }
  };

  var hasLocalStorageSupport = null;

  var localStorageAvailable = function localStorageAvailable() {
    if (hasLocalStorageSupport !== null) return hasLocalStorageSupport;

    try {
      hasLocalStorageSupport = window !== 'undefined' && window.localStorage !== null;
      var testKey = 'i18next.translate.boo';
      window.localStorage.setItem(testKey, 'foo');
      window.localStorage.removeItem(testKey);
    } catch (e) {
      hasLocalStorageSupport = false;
    }

    return hasLocalStorageSupport;
  };

  var localStorage = {
    name: 'localStorage',
    lookup: function lookup(options) {
      var found;

      if (options.lookupLocalStorage && localStorageAvailable()) {
        var lng = window.localStorage.getItem(options.lookupLocalStorage);
        if (lng) found = lng;
      }

      return found;
    },
    cacheUserLanguage: function cacheUserLanguage(lng, options) {
      if (options.lookupLocalStorage && localStorageAvailable()) {
        window.localStorage.setItem(options.lookupLocalStorage, lng);
      }
    }
  };

  var hasSessionStorageSupport = null;

  var sessionStorageAvailable = function sessionStorageAvailable() {
    if (hasSessionStorageSupport !== null) return hasSessionStorageSupport;

    try {
      hasSessionStorageSupport = window !== 'undefined' && window.sessionStorage !== null;
      var testKey = 'i18next.translate.boo';
      window.sessionStorage.setItem(testKey, 'foo');
      window.sessionStorage.removeItem(testKey);
    } catch (e) {
      hasSessionStorageSupport = false;
    }

    return hasSessionStorageSupport;
  };

  var sessionStorage = {
    name: 'sessionStorage',
    lookup: function lookup(options) {
      var found;

      if (options.lookupSessionStorage && sessionStorageAvailable()) {
        var lng = window.sessionStorage.getItem(options.lookupSessionStorage);
        if (lng) found = lng;
      }

      return found;
    },
    cacheUserLanguage: function cacheUserLanguage(lng, options) {
      if (options.lookupSessionStorage && sessionStorageAvailable()) {
        window.sessionStorage.setItem(options.lookupSessionStorage, lng);
      }
    }
  };

  var navigator$1 = {
    name: 'navigator',
    lookup: function lookup(options) {
      var found = [];

      if (typeof navigator !== 'undefined') {
        if (navigator.languages) {
          // chrome only; not an array, so can't use .push.apply instead of iterating
          for (var i = 0; i < navigator.languages.length; i++) {
            found.push(navigator.languages[i]);
          }
        }

        if (navigator.userLanguage) {
          found.push(navigator.userLanguage);
        }

        if (navigator.language) {
          found.push(navigator.language);
        }
      }

      return found.length > 0 ? found : undefined;
    }
  };

  var htmlTag = {
    name: 'htmlTag',
    lookup: function lookup(options) {
      var found;
      var htmlTag = options.htmlTag || (typeof document !== 'undefined' ? document.documentElement : null);

      if (htmlTag && typeof htmlTag.getAttribute === 'function') {
        found = htmlTag.getAttribute('lang');
      }

      return found;
    }
  };

  var path = {
    name: 'path',
    lookup: function lookup(options) {
      var found;

      if (typeof window !== 'undefined') {
        var language = window.location.pathname.match(/\/([a-zA-Z-]*)/g);

        if (language instanceof Array) {
          if (typeof options.lookupFromPathIndex === 'number') {
            if (typeof language[options.lookupFromPathIndex] !== 'string') {
              return undefined;
            }

            found = language[options.lookupFromPathIndex].replace('/', '');
          } else {
            found = language[0].replace('/', '');
          }
        }
      }

      return found;
    }
  };

  var subdomain = {
    name: 'subdomain',
    lookup: function lookup(options) {
      var found;

      if (typeof window !== 'undefined') {
        var language = window.location.href.match(/(?:http[s]*\:\/\/)*(.*?)\.(?=[^\/]*\..{2,5})/gi);

        if (language instanceof Array) {
          if (typeof options.lookupFromSubdomainIndex === 'number') {
            found = language[options.lookupFromSubdomainIndex].replace('http://', '').replace('https://', '').replace('.', '');
          } else {
            found = language[0].replace('http://', '').replace('https://', '').replace('.', '');
          }
        }
      }

      return found;
    }
  };

  function getDefaults() {
    return {
      order: ['querystring', 'cookie', 'localStorage', 'sessionStorage', 'navigator', 'htmlTag'],
      lookupQuerystring: 'lng',
      lookupCookie: 'i18next',
      lookupLocalStorage: 'i18nextLng',
      lookupSessionStorage: 'i18nextLng',
      // cache user language
      caches: ['localStorage'],
      excludeCacheFor: ['cimode'] //cookieMinutes: 10,
      //cookieDomain: 'myDomain'

    };
  }

  var Browser =
  /*#__PURE__*/
  function () {
    function Browser(services) {
      var options = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};

      _classCallCheck(this, Browser);

      this.type = 'languageDetector';
      this.detectors = {};
      this.init(services, options);
    }

    _createClass(Browser, [{
      key: "init",
      value: function init(services) {
        var options = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
        var i18nOptions = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : {};
        this.services = services;
        this.options = defaults(options, this.options || {}, getDefaults()); // backwards compatibility

        if (this.options.lookupFromUrlIndex) this.options.lookupFromPathIndex = this.options.lookupFromUrlIndex;
        this.i18nOptions = i18nOptions;
        this.addDetector(cookie$1);
        this.addDetector(querystring);
        this.addDetector(localStorage);
        this.addDetector(sessionStorage);
        this.addDetector(navigator$1);
        this.addDetector(htmlTag);
        this.addDetector(path);
        this.addDetector(subdomain);
      }
    }, {
      key: "addDetector",
      value: function addDetector(detector) {
        this.detectors[detector.name] = detector;
      }
    }, {
      key: "detect",
      value: function detect(detectionOrder) {
        var _this = this;

        if (!detectionOrder) detectionOrder = this.options.order;
        var detected = [];
        detectionOrder.forEach(function (detectorName) {
          if (_this.detectors[detectorName]) {
            var lookup = _this.detectors[detectorName].lookup(_this.options);

            if (lookup && typeof lookup === 'string') lookup = [lookup];
            if (lookup) detected = detected.concat(lookup);
          }
        });
        if (this.services.languageUtils.getBestMatchFromCodes) return detected; // new i18next v19.5.0

        return detected.length > 0 ? detected[0] : null; // a little backward compatibility
      }
    }, {
      key: "cacheUserLanguage",
      value: function cacheUserLanguage(lng, caches) {
        var _this2 = this;

        if (!caches) caches = this.options.caches;
        if (!caches) return;
        if (this.options.excludeCacheFor && this.options.excludeCacheFor.indexOf(lng) > -1) return;
        caches.forEach(function (cacheName) {
          if (_this2.detectors[cacheName]) _this2.detectors[cacheName].cacheUserLanguage(lng, _this2.options);
        });
      }
    }]);

    return Browser;
  }();

  Browser.type = 'languageDetector';

  return Browser;

})));