dissemination/lib/mixins/EventMixin.js

Lightweight event/command library created to replace Backbone.Radio

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports["default"] = void 0;
var EventMixin = {
  on: function on(name, listener) {
    var options = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : {};
    var once = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : false;

    if (!this._listeners) {
      this._listeners = {};
    }

    if (!this._listeners[name]) {
      this._listeners[name] = [];
    }

    this._listeners[name].push({
      listener: listener,
      options: options,
      once: !!once
    });
  },
  once: function once(name, listener, options) {
    this.on(name, listener, options, true);
  },
  off: function off(name, listener) {
    if (!this.listenersRegistered(name)) {
      throw new TypeError("Listeners for event \"".concat(name, "\" are not registered."));
    }

    if (listener === undefined) {
      // Removing all listeners for a given event
      delete this._listeners[name];
      return;
    }

    var index = this._listeners[name].findIndex(function (item) {
      return item.listener === listener;
    });

    if (index === -1) {
      throw new TypeError("Specified listener for event \"".concat(name, "\" is not registered."));
    }

    this._listeners[name].splice(index, 1);

    if (this._listeners[name].length === 0) {
      delete this._listeners[name];
    }
  },
  fire: function fire(name) {
    var params = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};

    if (!this._listeners || !this._listeners[name]) {
      return;
    }

    var listeners = this._listeners[name];

    for (var i = 0; i < listeners.length; i++) {
      var item = listeners[i];
      var listener = item.listener,
          options = item.options,
          _item$once = item.once,
          once = _item$once === void 0 ? false : _item$once;

      if (once) {
        listeners.splice(i, 1);
        i--;
      }

      if (listener(params, options) === false) {
        break;
      }
    }
  },
  listenersRegistered: function listenersRegistered(name) {
    return this._listeners && !!this._listeners[name];
  }
};
var _default = EventMixin;
exports["default"] = _default;