'use strict';

Object.defineProperty(exports, '__esModule', { value: true });

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);
  Object.defineProperty(Constructor, "prototype", {
    writable: false
  });
  return Constructor;
}

function _inherits(subClass, superClass) {
  if (typeof superClass !== "function" && superClass !== null) {
    throw new TypeError("Super expression must either be null or a function");
  }

  subClass.prototype = Object.create(superClass && superClass.prototype, {
    constructor: {
      value: subClass,
      writable: true,
      configurable: true
    }
  });
  Object.defineProperty(subClass, "prototype", {
    writable: false
  });
  if (superClass) _setPrototypeOf(subClass, superClass);
}

function _getPrototypeOf(o) {
  _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf.bind() : function _getPrototypeOf(o) {
    return o.__proto__ || Object.getPrototypeOf(o);
  };
  return _getPrototypeOf(o);
}

function _setPrototypeOf(o, p) {
  _setPrototypeOf = Object.setPrototypeOf ? Object.setPrototypeOf.bind() : function _setPrototypeOf(o, p) {
    o.__proto__ = p;
    return o;
  };
  return _setPrototypeOf(o, p);
}

function _isNativeReflectConstruct() {
  if (typeof Reflect === "undefined" || !Reflect.construct) return false;
  if (Reflect.construct.sham) return false;
  if (typeof Proxy === "function") return true;

  try {
    Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function () {}));
    return true;
  } catch (e) {
    return false;
  }
}

function _assertThisInitialized(self) {
  if (self === void 0) {
    throw new ReferenceError("this hasn't been initialised - super() hasn't been called");
  }

  return self;
}

function _possibleConstructorReturn(self, call) {
  if (call && (typeof call === "object" || typeof call === "function")) {
    return call;
  } else if (call !== void 0) {
    throw new TypeError("Derived constructors may only return object or undefined");
  }

  return _assertThisInitialized(self);
}

function _createSuper(Derived) {
  var hasNativeReflectConstruct = _isNativeReflectConstruct();

  return function _createSuperInternal() {
    var Super = _getPrototypeOf(Derived),
        result;

    if (hasNativeReflectConstruct) {
      var NewTarget = _getPrototypeOf(this).constructor;

      result = Reflect.construct(Super, arguments, NewTarget);
    } else {
      result = Super.apply(this, arguments);
    }

    return _possibleConstructorReturn(this, result);
  };
}

function _superPropBase(object, property) {
  while (!Object.prototype.hasOwnProperty.call(object, property)) {
    object = _getPrototypeOf(object);
    if (object === null) break;
  }

  return object;
}

function _get() {
  if (typeof Reflect !== "undefined" && Reflect.get) {
    _get = Reflect.get.bind();
  } else {
    _get = function _get(target, property, receiver) {
      var base = _superPropBase(target, property);

      if (!base) return;
      var desc = Object.getOwnPropertyDescriptor(base, property);

      if (desc.get) {
        return desc.get.call(arguments.length < 3 ? target : receiver);
      }

      return desc.value;
    };
  }

  return _get.apply(this, arguments);
}

var Emitter = /*#__PURE__*/function () {
  function Emitter() {
    _classCallCheck(this, Emitter);

    Object.defineProperty(this, 'listeners', {
      value: {},
      writable: true,
      configurable: true
    });
  }

  _createClass(Emitter, [{
    key: "addEventListener",
    value: function addEventListener(type, callback, options) {
      if (!(type in this.listeners)) {
        this.listeners[type] = [];
      }

      this.listeners[type].push({
        callback: callback,
        options: options
      });
    }
  }, {
    key: "removeEventListener",
    value: function removeEventListener(type, callback) {
      if (!(type in this.listeners)) {
        return;
      }

      var stack = this.listeners[type];

      for (var i = 0, l = stack.length; i < l; i++) {
        if (stack[i].callback === callback) {
          stack.splice(i, 1);
          return;
        }
      }
    }
  }, {
    key: "dispatchEvent",
    value: function dispatchEvent(event) {
      if (!(event.type in this.listeners)) {
        return;
      }

      var stack = this.listeners[event.type];
      var stackToCall = stack.slice();

      for (var i = 0, l = stackToCall.length; i < l; i++) {
        var listener = stackToCall[i];

        try {
          listener.callback.call(this, event);
        } catch (e) {
          Promise.resolve().then(function () {
            throw e;
          });
        }

        if (listener.options && listener.options.once) {
          this.removeEventListener(event.type, listener.callback);
        }
      }

      return !event.defaultPrevented;
    }
  }]);

  return Emitter;
}();

var AbortSignal = /*#__PURE__*/function (_Emitter) {
  _inherits(AbortSignal, _Emitter);

  var _super = _createSuper(AbortSignal);

  function AbortSignal() {
    var _this;

    _classCallCheck(this, AbortSignal);

    _this = _super.call(this); // Some versions of babel does not transpile super() correctly for IE <= 10, if the parent
    // constructor has failed to run, then "this.listeners" will still be undefined and then we call
    // the parent constructor directly instead as a workaround. For general details, see babel bug:
    // https://github.com/babel/babel/issues/3041
    // This hack was added as a fix for the issue described here:
    // https://github.com/Financial-Times/polyfill-library/pull/59#issuecomment-477558042

    if (!_this.listeners) {
      Emitter.call(_assertThisInitialized(_this));
    } // Compared to assignment, Object.defineProperty makes properties non-enumerable by default and
    // we want Object.keys(new AbortController().signal) to be [] for compat with the native impl


    Object.defineProperty(_assertThisInitialized(_this), 'aborted', {
      value: false,
      writable: true,
      configurable: true
    });
    Object.defineProperty(_assertThisInitialized(_this), 'onabort', {
      value: null,
      writable: true,
      configurable: true
    });
    Object.defineProperty(_assertThisInitialized(_this), 'reason', {
      value: undefined,
      writable: true,
      configurable: true
    });
    return _this;
  }

  _createClass(AbortSignal, [{
    key: "toString",
    value: function toString() {
      return '[object AbortSignal]';
    }
  }, {
    key: "dispatchEvent",
    value: function dispatchEvent(event) {
      if (event.type === 'abort') {
        this.aborted = true;

        if (typeof this.onabort === 'function') {
          this.onabort.call(this, event);
        }
      }

      _get(_getPrototypeOf(AbortSignal.prototype), "dispatchEvent", this).call(this, event);
    }
  }]);

  return AbortSignal;
}(Emitter);
var AbortController = /*#__PURE__*/function () {
  function AbortController() {
    _classCallCheck(this, AbortController);

    // Compared to assignment, Object.defineProperty makes properties non-enumerable by default and
    // we want Object.keys(new AbortController()) to be [] for compat with the native impl
    Object.defineProperty(this, 'signal', {
      value: new AbortSignal(),
      writable: true,
      configurable: true
    });
  }

  _createClass(AbortController, [{
    key: "abort",
    value: function abort(reason) {
      var event;

      try {
        event = new Event('abort');
      } catch (e) {
        if (typeof document !== 'undefined') {
          if (!document.createEvent) {
            // For Internet Explorer 8:
            event = document.createEventObject();
            event.type = 'abort';
          } else {
            // For Internet Explorer 11:
            event = document.createEvent('Event');
            event.initEvent('abort', false, false);
          }
        } else {
          // Fallback where document isn't available:
          event = {
            type: 'abort',
            bubbles: false,
            cancelable: false
          };
        }
      }

      var signalReason = reason;

      if (signalReason === undefined) {
        if (typeof document === 'undefined') {
          signalReason = new Error('This operation was aborted');
          signalReason.name = 'AbortError';
        } else {
          try {
            signalReason = new DOMException('signal is aborted without reason');
          } catch (err) {
            // IE 11 does not support calling the DOMException constructor, use a
            // regular error object on it instead.
            signalReason = new Error('This operation was aborted');
            signalReason.name = 'AbortError';
          }
        }
      }

      this.signal.reason = signalReason;
      this.signal.dispatchEvent(event);
    }
  }, {
    key: "toString",
    value: function toString() {
      return '[object AbortController]';
    }
  }]);

  return AbortController;
}();

if (typeof Symbol !== 'undefined' && Symbol.toStringTag) {
  // These are necessary to make sure that we get correct output for:
  // Object.prototype.toString.call(new AbortController())
  AbortController.prototype[Symbol.toStringTag] = 'AbortController';
  AbortSignal.prototype[Symbol.toStringTag] = 'AbortSignal';
}

function polyfillNeeded(self) {
  if (self.__FORCE_INSTALL_ABORTCONTROLLER_POLYFILL) {
    console.log('__FORCE_INSTALL_ABORTCONTROLLER_POLYFILL=true is set, will force install polyfill');
    return true;
  } // Note that the "unfetch" minimal fetch polyfill defines fetch() without
  // defining window.Request, and this polyfill need to work on top of unfetch
  // so the below feature detection needs the !self.AbortController part.
  // The Request.prototype check is also needed because Safari versions 11.1.2
  // up to and including 12.1.x has a window.AbortController present but still
  // does NOT correctly implement abortable fetch:
  // https://bugs.webkit.org/show_bug.cgi?id=174980#c2


  return typeof self.Request === 'function' && !self.Request.prototype.hasOwnProperty('signal') || !self.AbortController;
}

/**
 * Note: the "fetch.Request" default value is available for fetch imported from
 * the "node-fetch" package and not in browsers. This is OK since browsers
 * will be importing umd-polyfill.js from that path "self" is passed the
 * decorator so the default value will not be used (because browsers that define
 * fetch also has Request). One quirky setup where self.fetch exists but
 * self.Request does not is when the "unfetch" minimal fetch polyfill is used
 * on top of IE11; for this case the browser will try to use the fetch.Request
 * default value which in turn will be undefined but then then "if (Request)"
 * will ensure that you get a patched fetch but still no Request (as expected).
 * @param {fetch, Request = fetch.Request}
 * @returns {fetch: abortableFetch, Request: AbortableRequest}
 */

function abortableFetchDecorator(patchTargets) {
  if ('function' === typeof patchTargets) {
    patchTargets = {
      fetch: patchTargets
    };
  }

  var _patchTargets = patchTargets,
      fetch = _patchTargets.fetch,
      _patchTargets$Request = _patchTargets.Request,
      NativeRequest = _patchTargets$Request === void 0 ? fetch.Request : _patchTargets$Request,
      NativeAbortController = _patchTargets.AbortController,
      _patchTargets$__FORCE = _patchTargets.__FORCE_INSTALL_ABORTCONTROLLER_POLYFILL,
      __FORCE_INSTALL_ABORTCONTROLLER_POLYFILL = _patchTargets$__FORCE === void 0 ? false : _patchTargets$__FORCE;

  if (!polyfillNeeded({
    fetch: fetch,
    Request: NativeRequest,
    AbortController: NativeAbortController,
    __FORCE_INSTALL_ABORTCONTROLLER_POLYFILL: __FORCE_INSTALL_ABORTCONTROLLER_POLYFILL
  })) {
    return {
      fetch: fetch,
      Request: Request
    };
  }

  var Request = NativeRequest; // Note that the "unfetch" minimal fetch polyfill defines fetch() without
  // defining window.Request, and this polyfill need to work on top of unfetch
  // hence we only patch it if it's available. Also we don't patch it if signal
  // is already available on the Request prototype because in this case support
  // is present and the patching below can cause a crash since it assigns to
  // request.signal which is technically a read-only property. This latter error
  // happens when you run the main5.js node-fetch example in the repo
  // "abortcontroller-polyfill-examples". The exact error is:
  //   request.signal = init.signal;
  //   ^
  // TypeError: Cannot set property signal of #<Request> which has only a getter

  if (Request && !Request.prototype.hasOwnProperty('signal') || __FORCE_INSTALL_ABORTCONTROLLER_POLYFILL) {
    Request = function Request(input, init) {
      var signal;

      if (init && init.signal) {
        signal = init.signal; // Never pass init.signal to the native Request implementation when the polyfill has
        // been installed because if we're running on top of a browser with a
        // working native AbortController (i.e. the polyfill was installed due to
        // __FORCE_INSTALL_ABORTCONTROLLER_POLYFILL being set), then passing our
        // fake AbortSignal to the native fetch will trigger:
        // TypeError: Failed to construct 'Request': member signal is not of type AbortSignal.

        delete init.signal;
      }

      var request = new NativeRequest(input, init);

      if (signal) {
        Object.defineProperty(request, 'signal', {
          writable: false,
          enumerable: false,
          configurable: true,
          value: signal
        });
      }

      return request;
    };

    Request.prototype = NativeRequest.prototype;
  }

  var realFetch = fetch;

  var abortableFetch = function abortableFetch(input, init) {
    var signal = Request && Request.prototype.isPrototypeOf(input) ? input.signal : init ? init.signal : undefined;

    if (signal) {
      var abortError;

      try {
        abortError = new DOMException('Aborted', 'AbortError');
      } catch (err) {
        // IE 11 does not support calling the DOMException constructor, use a
        // regular error object on it instead.
        abortError = new Error('Aborted');
        abortError.name = 'AbortError';
      } // Return early if already aborted, thus avoiding making an HTTP request


      if (signal.aborted) {
        return Promise.reject(abortError);
      } // Turn an event into a promise, reject it once `abort` is dispatched


      var cancellation = new Promise(function (_, reject) {
        signal.addEventListener('abort', function () {
          return reject(abortError);
        }, {
          once: true
        });
      });

      if (init && init.signal) {
        // Never pass .signal to the native implementation when the polyfill has
        // been installed because if we're running on top of a browser with a
        // working native AbortController (i.e. the polyfill was installed due to
        // __FORCE_INSTALL_ABORTCONTROLLER_POLYFILL being set), then passing our
        // fake AbortSignal to the native fetch will trigger:
        // TypeError: Failed to execute 'fetch' on 'Window': member signal is not of type AbortSignal.
        delete init.signal;
      } // Return the fastest promise (don't need to wait for request to finish)


      return Promise.race([cancellation, realFetch(input, init)]);
    }

    return realFetch(input, init);
  };

  return {
    fetch: abortableFetch,
    Request: Request
  };
}

exports.AbortController = AbortController;
exports.AbortSignal = AbortSignal;
exports.abortableFetch = abortableFetchDecorator;