topic-subscribe/build/topic-subscribe.node.js

Universal PubSub module for node (including old versions) and browser with subscription filtering and broadcasting.

'use strict';

/**
 * Turn the given value into an array.  If it is already an array then return it; if it is a set then convert to an
 * array; and if neither then return as the first item in an array. The purpose of this function is for function
 * or method parameters where they can be either a array or not.  You can use this to ensure you are working on
 * an array.
 *
 * @public
 * @param {Array|Set|*} value		Value to return or convert.
 * @returns {Array}					The converted value (or original if already an array).
 */
function makeArray(value) {
	if (value === undefined) return [];
	if (value instanceof Set) return [...value];
	return Array.isArray(value) ? value : [value];
}

/**
 * Test whether the given value a string?
 *
 * @public
 * @param {*} value			Value to test.
 * @returns {boolean}		Is it a string?
 */
function isString(value) {
	return typeof value === 'string';
}

/**
 * Is the given value a function.
 *
 * @public
 * @param {*} value			Value to test.
 * @returns {boolean}		Is it a function?
 */
function isFunction(value) {
	return !!(value && value.constructor && value.call && value.apply);
}

/**
 * Test whether the given value a standard object (and not null).
 *
 * @public
 * @param {*} value			Value to test.
 * @returns {boolean}		Is it an object?
 */
function isObject(value) {
	return Object.prototype.toString.call(value) === '[object Object]' && !(value === null);
}

/**
 * Is the given value a RegExp.
 *
 * @public
 * @param {*} value			Value to test.
 * @returns {boolean}		Is it a RegExp?
 */
function isRegExp(value) {
	return value instanceof RegExp;
}

/**
 * Lop an item of the end of a string with the given separator.  The separator defaults to '/' for handling
 * file-like paths.
 *
 * @public
 * @param {string} text					Text to perform lop on.
 * @param {string} [separator='/']		The separator to use.
 * @returns {string}					Lopped string.
 */
function lop(text, separator = '/') {
	const parts = text.split(separator);
	parts.pop();
	return parts.join(separator);
}

/**
 * Generator for given lop operation.
 *
 * @public
 * @generator
 * @param {string} text					Text to perform lopping on.
 * @param {string} [separator='/']		The separator to use.
 * @yields {string}						Lopped text.
 */
function* lopper(text, separator = '/') {
	let _text = text;
	let last = _text;

	while (_text.length) {
		last = _text;
		yield _text;
		_text = lop(_text, separator = '/');
	}
	if (last !== '/') yield '/';
}

/**
 * Get all the property names (including inherited) of the given object.
 *
 * @public
 * @param {Object} obj		The object to get properties for.
 * @returns {Set}			A set of all the property names.
 */
function getAllPropertyNames(obj) {
	const all = new Set();

	do {
		Object.getOwnPropertyNames(obj).forEach(property => all.add(property));
	} while (obj = Object.getPrototypeOf(obj));

	return all;
}

/**
 * Perform a clone (with deep option) of given object.  Methods are bound to the cloned object.
 *
 * @note This will not clone getter/setters but only their value at clone time.  It does not climb the prototype chain,
 * so no inherited properties are cloned.
 *
 * @param {Object} obj				Object to clone.
 * @param {boolean} [deep=false]	Do a deep clone?
 * @returns {Object}				Cloned object.
 */
function clone(obj, deep = false) {
	const _obj = {};

	Object.getOwnPropertyNames(obj).forEach(property => {
		if (isFunction(obj[property])) {
			_obj[property] = obj[property].bind(_obj);
		} else if (!deep || Array.isArray(obj[property]) || !isObject(obj[property])) {
			_obj[property] = obj[property];
		} else {
			_obj[property] = clone(obj[property], deep);
		}
	});

	return _obj;
}

const $private = new WeakMap();

/**
 * Given a collection, test whether an item exists and if not use the given constructor and constructor parameters
 * to create the value.  The collection can be a Set, Map, Array or Object.
 *
 * @param {Map|Set|Array|Object} collection		The collection to test and set on.
 * @param {string} item							The item to set.
 * @param {Object} constructor					The constructor to use.
 * @param {Array.<*>} [...constructorParams]	The parameters to use on the constructor.
 * @returns {*}
 */
function hasConstruct(collection, item, constructor, ...constructorParams) {
	if (constructor) {
		if (collection.has && !collection.has(item)) {
			if (collection.set) return collection.set(item, new constructor(...constructorParams));
			if (collection.add) return collection.add(new constructor(...constructorParams));
		} else if (Array.isArray(collection) && !collection.includes(item)) {
			collection.push(new constructor(...constructorParams));
		} else if (!getAllPropertyNames(collection).has(item)) {
			collection[item] = new constructor(...constructorParams);
		}
	}
}

/**
 * Class for maintaining private values in a given class.
 *
 * @class
 */
class Private {
	/**
  * Get a given private value on the given class instance.  A constructor can be supplied with construct
  * arguments if the value does not exist. If no values exist for given instance create a new value map for
  * future use.
  *
  * @static
  * @method
  * @public
  * @param {Object} classInstance				The class instance to get for.
  * @param {string} property						The property to get.
  * @param {Object} [defaultConstructor]			The constructor to use for new values.
  * @param {Array.<*>} [...constructorParams]	The parameters to pass to the constructor.
  * @returns {*}
  */
	static get(classInstance, property, defaultConstructor, ...constructorParams) {
		hasConstruct($private, classInstance, Map);
		hasConstruct($private.get(classInstance), property, defaultConstructor, ...constructorParams);
		return $private.get(classInstance).get(property);
	}

	/**
  * Set a private value on a given class instance.
  *
  * @static
  * @method
  * @public
  * @param {Object} classInstance	The class instance to set on.
  * @param {string} property			The property to set.
  * @param {*} value					The value to set.
  * @returns {boolean}				Did the value set?
  */
	static set(classInstance, property, value) {
		hasConstruct($private, classInstance, Map);
		return $private.get(classInstance).set(property, value);
	}
}

//removeIf(browser)
//endRemoveIf(browser)

const errors = {
	'CallbackNotFunction': () => `Expected callback to be a function.`,
	'ChannelNotAString': () => `Expected channel to be a channel string (starting with a slash) or regular-expression.`,
	'FilterNotAnObject': () => `Expected filter to be an object.`
};

/**
 * Create an error object against the given id.  If id supplied then look it up in errors object.
 *
 * @public
 * @param {Object} errorConstructor			Error constructor object.
 * @param {string|function|*} errorId		The error id to lookup and use text of.  If id is not found assume id is
 * 											the text to apply to the error. If id is function run function with
 * 										 	supplied parameters to get error constructor params.
 * @param params							Parameters to run through the function returned by error id lookup.
 * @returns {Error}							New error instance that can be thrown.
 */
function createError(errorConstructor, errorId, ...params) {
	if (errors[errorId]) {
		if (isFunction(errors[errorId])) return new errorConstructor(errors[errorId](...params));
		return new errorConstructor(errors[errorId]);
	}
	return new errorConstructor(errorId);
}

//removeIf(browser)
'use strict';

//endRemoveIf(browser)

const AT_TARGET = Symbol('Message at target');
const BUBBLING_PHASE = Symbol('Message in bubbling phase');

/**
 * Message class, this is the class that is passed to listeners, it contains all the given data and other event style
 * information that might be useful.  Each listener get's it's own instance of the class.
 *
 * @class
 */
class Message {
	/**
  * Create a new event instance.
  *
  * @method
  * @param {*} message				The message being published/broadcast.
  * @param {Object} options			The construction options (including channels).
  */
	constructor(message, options) {
		message = message || {};

		Private.set(this, 'data', message);
		Private.set(this, 'target', options.target);
		Private.set(this, 'currentTarget', options.currentTarget);
		if (options.broadcast) Private.set(this, 'broadcast', !!options.broadcast);
		if (options.publish) Private.set(this, 'publish', !!options.publish);
		Private.set(this, 'timestamp', new Date().getTime());
		if (message.sourceTimestamp || message.timestamp) {
			Private.set(this, 'sourceTimestamp', message.sourceTimestamp || message.timestamp);
		}

		const atTarget = !!makeArray(options.target).find(channel => isRegExp(channel) ? channel.test(options.currentTarget) : channel === options.currentTarget);

		Private.set(this, 'eventPhase', atTarget ? Message.AT_TARGET : Message.BUBBLING_PHASE);
	}

	/**
  * The message data.
  *
  * @public
  * @property {*}
  */
	get data() {
		return Private.get(this, 'data');
	}

	/**
  * The original channel this was published/broadcast to.
  *
  * @public
  * @property {Array}
  */
	get target() {
		return Private.get(this, 'target');
	}

	/**
  * The channel now receiving the message (might be different due to broadcast and publish bubbling).
  *
  * @public
  * @property {Array}
  */
	get currentTarget() {
		return Private.get(this, 'currentTarget');
	}

	/**
  * Is the message a broadcast message?
  *
  * @public
  * @property {boolean}
  */
	get broadcast() {
		return Private.get(this, 'broadcast');
	}

	/**
  * Is the message a publish message?.
  *
  * @public
  * @property {boolean}
  */
	get publish() {
		return Private.get(this, 'publish');
	}

	/**
  * The timestamp on message creation.
  *
  * @public
  * @property {integer}		Time in milliseconds.
  */
	get timestamp() {
		return Private.get(this, 'timestamp');
	}

	/**
  * The timestamp from original message if a mirrored message.
  *
  * @public
  * @property {integer|undefined}		Time in milliseconds or undefined if not available.
  */
	get sourceTimestamp() {
		return Private.get(this, 'sourceTimestamp');
	}

	/**
  * The current event phase (bubbling or not).
  *
  * @public
  * @property {Symbol}		The phase value.
  */
	get eventPhase() {
		return Private.get(this, 'eventPhase');
	}

	static get AT_TARGET() {
		return AT_TARGET;
	}

	static get BUBBLING_PHASE() {
		return BUBBLING_PHASE;
	}
}

//removeIf(browser)
module.exports = Message;
//endRemoveIf(browser)
//removeIf(browser)
const sift = require('sift');
//endRemoveIf(browser)

//removeIf(browser)
//endRemoveIf(browser)

const listenerToChannel = new WeakMap();

/**
 * Apply a given action on a given set, against a given channel with the given subscription.
 *
 * @param {Set} subscriptions				The subscriptions to work on.
 * @param {string} channel					The channel to apply this with.
 * @param {string} action					The action to do.
 * @param {object} subscription				The subscription object to apply.
 */
function _subscriptionAction(subscriptions, channel, action, subscription) {
	if (!subscriptions.has(channel)) subscriptions.set(channel, new Set());
	subscriptions.get(channel)[action](subscription);
}

/**
 * Perform a give action on all on the channels supplied using the subscription value supplied.  This is basically, a
 * way of performing the same action on a sets (eg. add or delete).
 *
 * @private
 * @param {Set} subscriptions				The subscriptions to work on.
 * @param {Array.<string|RegExp>} channels	The channels to apply this with.
 * @param {string} action					The action to do.
 * @param {object} subscription				The subscription object to apply.
 */
function _subscriptionsAction(subscriptions, channels, action, subscription) {
	channels.forEach(channel => _subscriptionAction(subscriptions, channel, action, subscription));
}

/**
 * Test an array of channels returning true if all channels are correct type and format.  Returns false if any of the
 * channels fail the criteria.
 *
 * @private
 * @param {Array<string|RegExp>} channels	Channels to test.
 * @param {boolean} allowRegExp				Do we allow regular expressions for channels?
 * @returns {boolean}						Did they all pass?
 */
function _allChannelsAreCorrectType(channels, allowRegExp = true) {
	return channels.filter(channel => isString(channel) ? channel.charAt(0) === '/' : allowRegExp ? isRegExp(channel) : false).length === channels.length;
}

/**
 * Generator for all ancestor channels of a given array of channels.
 *
 * @private
 * @generator
 * @param {Array.<string>} channels		Channels to expand.
 * @yields {string}						Channel.
 */
function* _allAncestorChannels(channels) {
	const loppers = channels.map(channel => lopper(channel));

	while (true) {
		let done = 0;
		for (let n = 0; n < loppers.length; n++) {
			let value = loppers[n].next();
			if (!value.done) {
				yield value.value;
			} else {
				done++;
			}
		}
		if (done >= loppers.length) break;
	}
}

/**
 * Get an array of unique ancestor channels from array of channels.
 *
 * @private
 * @param {Array.<string>} channels		Channels array.
 * @returns {Array.<string>}			All calculated channels.
 */
function _uniqueChannels(channels) {
	const uniqueChannels = new Set();

	const lopper = _allAncestorChannels(channels);
	for (let channel of lopper) uniqueChannels.add(channel);

	return Array.from(uniqueChannels);
}

/**
 * Take a channel string and trim any trailing slashes or empty channel parts.
 *
 * @private
 * @param {sgtring} channel		Thr channel to trim.
 * @returns {string}			The trimmed channel.
 */
function _removingTrailingSlash(channel) {
	return isString(channel) && channel.charAt(0) === '/' ? '/' + channel.split('/').filter(part => part.trim() !== '').join('/') : channel;
}

/**
 * Send a given message to listeners in supplied Set.
 *
 * @private
 * @param {Set.<function>} listeners		Listeners to send messages to.
 * @param {*} message						Message to send.
 * @param {Object} options					Options object used in Message constructor
 * @returns {boolean}						Did any listeners receive?
 */
function _messageListeners(listeners, message, options) {
	listeners.forEach(listener => {
		listener(new Message(message, Object.assign({}, options, {
			currentTarget: getChannelForListener(listeners, listener)
		})));
	});
	return !!listeners.size;
}

function addToFilterSet(filterSet, listener, channel) {
	if (!filterSet.has(listener)) {
		if (!listenerToChannel.has(filterSet)) listenerToChannel.set(filterSet, new WeakMap());
		listenerToChannel.get(filterSet).set(listener, channel);
		filterSet.add(listener);
	}
}

function getChannelForListener(filterSet, listener) {
	if (listenerToChannel.has(filterSet)) return listenerToChannel.get(filterSet).get(listener);
}

/**
 * Add listeners to a set based on whether the given message passes the subscription filter.
 *
 * @private
 * @param {Set} listeners		The listeners to filter.
 * @param {string} channel		Channel listener isattached to.
 * @param {*} message			The message to test against.
 * @param {Set} filterSet		The set to add filtered listeners to.
 */
function _filterListeners(listeners, channel, message, filterSet) {
	listeners.forEach(subscription => {
		if (sift(subscription.filter, [message]).length) {
			if (!filterSet.has(subscription.listener)) addToFilterSet(filterSet, subscription.listener, channel);
		}
	});
}

/**
 * Generator that perform filtered matching from a given lookup of listeners. Run a test function against each channel
 * and yield listeners for each that passes.
 *
 * @private
 * @generator
 * @param {Map} listenerLookup					Channel lookup to cycle through running channel tests against.
 * @param {Array.<string|RegExp>} channels		Channels.
 * @param {function} channelTest				Channel test function.
 * @yields {Set}								Listeners from matching channel.
 */
function* _channelMatcher(listenerLookup, channels, channelTest) {
	for (let [listenerChannel, listeners] of listenerLookup) {
		const filteredChannels = channels.filter(channel => channelTest(listenerChannel, channel));
		if (filteredChannels.length) yield [listenerChannel, listeners];
	}
}

/**
 * Generator for obtaining listeners for given channels.
 *
 * @private
 * @generator
 * @param {Map} listenerLookup					Lookup to test against.
 * @param {Array.<string|RegExp>} channels		Channels to look for.
 * @yield {Set}									Listeners found.
 */
function* _inChannelsLookup(listenerLookup, channels) {
	for (let n = 0; n < channels.length; n++) {
		if (listenerLookup.has(channels[n])) yield [channels[n], listenerLookup.get(channels[n])];
	}
}

/**
 * Given a set of channels and a listener lookup map, get the listeners to publish to.
 *
 * @private
 * @param {Map} listenerLookup					The listener lookup map.
 * @param {Array.<string|RegExp>} channels		The channels array.
 * @param {Object} message						The message we are publishing.
 * @returns {Set.<Function>}					The listeners.
 */
function _getPublishTo(listenerLookup, channels, message) {
	const publishTo = new Set();
	const matcher1 = _channelMatcher(listenerLookup, channels, (listenerChannel, channel) => {
		if (isRegExp(listenerChannel)) return listenerChannel.test(channel);
	});
	const matcher2 = _inChannelsLookup(listenerLookup, channels);

	for (const [listenerChannel, listeners] of [...matcher1, ...matcher2]) _filterListeners(listeners, listenerChannel, message, publishTo);
	return publishTo;
}

/**
 * Given a set of channels and a listener lookup map, get the listeners to broadcast to.
 *
 * @private
 * @param {Map} listenerLookup			The listener lookup map.
 * @param {Array.<string>} channels		The channels array.
 * @param {Object} message				The message we are broadcasting.
 * @returns {Set.<Function>}			The listeners.
 */
function _getBroadcastTo(listenerLookup, channels, message) {
	const broadcastTo = new Set();
	const matcher = _channelMatcher(listenerLookup, channels, (listenerChannel, channel) => {
		if (isRegExp(listenerChannel)) return false;
		return listenerChannel.substr(0, channel.length) === channel;
	});

	for (const [listenerChannel, listeners] of matcher) _filterListeners(listeners, listenerChannel, message, broadcastTo);

	return broadcastTo;
}

/**
 * Given a channel, and a listener lookup map unsubscribe all listeners from it.
 *
 * @private
 * @param {Map} listenerLookup			The listener lookup to use.
 * @param {string|RegExp} channel		The channel to unsubscribe listeners from.
 * @returns {boolean}					Did anything unsubscibe?
 */
function _unsubscribeChannel(listenerLookup, channel) {
	let unsubscribed = false;

	if (listenerLookup.has(channel)) {
		listenerLookup.get(channel).clear();
		listenerLookup.delete(channel);
		unsubscribed = true;
	}

	return unsubscribed;
}

/**
 * Given a listener and listener lookup map, unsubscribe the listener on every channel it listens on.
 *
 * @private
 * @param {Map} listenerLookup			The listener lookup to use.
 * @param {Function} listener			The listener to unsubscribe.
 * @returns {boolean}					Did anything unsubscibe?
 */
function _unsubscribeListener(listenerLookup, listener) {
	let unsubscribed = false;

	listenerLookup.forEach(subscriptions => {
		subscriptions.forEach(subscription => {
			if (subscription.listener === listener) {
				subscriptions.delete(subscription);
				unsubscribed = true;
			}
		});
	});

	return unsubscribed;
}

/**
 * Get an array of channels corrected with no-trailing slashes from given array, string or regular-expression.
 *
 * @private
 * @param {string|Array|set} channels		Channel(s) to publish on (including RegExp).
 * @returns {Array.<string|RegExp>} 		The channels to publish on.
 */
function _getCorrectedChannelsArray(channels) {
	const correctedChannels = makeArray(channels).map(channel => _removingTrailingSlash(channel));
	if (!_allChannelsAreCorrectType(correctedChannels, false)) throw createError(TypeError, 'ChannelNotAString');
	return correctedChannels;
}

/**
 * Parse the given message to make ready for publishing / broadcasting via PubSub.
 *
 * @private
 * @param {Message|Object|*} message			The message object to mirror.
 * @param {Array.<Function>} [parsers=[]]		The parsers to use in converting into the correct format.
 * @param {string} [base='']					The base to prepend to channels.
 * @returns {Object}							The parsed message object.
 */
function _mirrorMessageParse(message, parsers = [], base = '') {
	let _message = clone(message || {});
	base = isString(parsers) ? parsers : base;

	(isString(parsers) ? [] : makeArray(parsers)).forEach(parser => {
		_message = parser(_message, base) || _message;
	});

	_message.target = makeArray(_message.target || []);
	_message.target = (_message.target.length ? _message.target : base !== '' ? [''] : []).map(channel => {
		if (isString(channel)) return base + channel;
		return channel;
	});

	return _message;
}

function getSourceSubscriber(pubsub, name) {
	const sourceSubscribers = Private.get(pubsub, 'sourceSubscribers', Map);
	const staticSourceSubscribers = Private.get(PubSub, 'sourceSubscribers', Map);
	return sourceSubscribers.get(name) || staticSourceSubscribers.get(name);
}

function _sourceGeneric(emitter, method, channel, params) {
	params.forEach(params => emitter[method](channel, ...params));
}

function _getOnParams(pubsub, channel, options) {
	return makeArray(channel).map(channel => {
		return [(message, ...params) => {
			pubsub.mirror(message, options.parsers, options.base);
		}];
	});
}

/**
 * Given an subscription method (like PubSub) on an emitter, mirror given events to pubsub instance. The method name is
 * given via options.on.
 *
 * @private
 * @param {PubSub} pubsub				PubSub instance to mirror to.
 * @param {Object} emitter				Emitter to source from.
 * @param {Array|string} channel		Channel(s) to listen on.
 * @param {Object} options				Options used to create mirroring.
 */
function _sourceSubscribe(pubsub, emitter, channel, options) {
	const params = _getOnParams(pubsub, channel, options).map(params => {
		if (options.filter) params.unshift(options.filter);
		return params;
	});

	_sourceGeneric(emitter, 'subscribe', channel, params);
}

/**
 * Given an addEventListener subscription method (DOM style) on an emitter, mirror given events to pubsub instance.
 * The method name is given via options.on.
 *
 * @private
 * @param {PubSub} pubsub				PubSub instance to mirror to.
 * @param {Object} emitter				Emitter to source from.
 * @param {Array|string} channel		Channel(s) to listen on.
 * @param {Object} options				Options used to create mirroring.
 */
function _sourceAddEventListener(pubsub, emitter, channel, options) {
	const params = _getOnParams(pubsub, channel, options).map(params => {
		if (options.options) {
			params.push(options.options);
		} else if (options.useCapture) {
			params.push(options.useCapture);
			if (options.wantsUntrusted) params.push(options.wantsUntrusted);
		}
		return params;
	});
	_sourceGeneric(emitter, 'addEventListener', channel, params);
}

/**
 * Given an $on style (Angular like) subscription method on an emitter, mirror given events to pubsub instance. The
 * method name is given via options.on.
 *
 * @private
 * @param {PubSub} pubsub				PubSub instance to mirror to.
 * @param {Object} emitter				Emitter to source from.
 * @param {Array|string} channel		Channel(s) to listen on.
 * @param {Object} options				Options used to create mirroring.
 */
function _source$On(pubsub, emitter, channel, options) {
	_sourceGeneric(emitter, '$on', channel, _getOnParams(pubsub, channel, options));
}

/**
 * Given an user-defined subscription method on an emitter, mirror given events to pubsub instance. The method name is
 * given via options.on.
 *
 * @private
 * @param {PubSub} pubsub				PubSub instance to mirror to.
 * @param {Object} emitter				Emitter to source from.
 * @param {Array|string} channel		Channel(s) to listen on.
 * @param {Object} options				Options used to create mirroring.
 */
function _sourceUserDefined(pubsub, emitter, channel, options) {
	const params = _getOnParams(pubsub, channel, options).map(params => {
		return [...makeArray(options.beforeListenerParams), ...params, ...makeArray(options.afterListenerParams)];
	});

	_sourceGeneric(emitter, options.on, channel, params);
}

/**
 * Given an on style method (jQuery-like) on an emitter, mirror given events to pubsub instance.
 *
 * @private
 * @param {PubSub} pubsub				PubSub instance to mirror to.
 * @param {Object} emitter				Emitter to source from.
 * @param {Array|string} channel		Channel(s) to listen on.
 * @param {Object} options				Options used to create mirroring.
 */
function _sourceOn(pubsub, emitter, channel, options) {
	const params = _getOnParams(pubsub, channel, options).map(params => {
		if (options.selector) params.unshift(options.selector);
		if (options.data) params.unshift(options.data);
		return params;
	});
	_sourceGeneric(emitter, 'on', channel, params);
}

/**
 * Publish a message to the given listeners on the given channels.
 *
 * @param {Map} listenerLookup					The listener lookup to use.
 * @param {Array.<string|RegExp>} channels		The channels to publish on.
 * @param {*} message							The publish message.
 * @returns {boolean}							Did any listeners receive the message.
 */
function _publish(listenerLookup, channels, message) {
	const publishTo = _getPublishTo(listenerLookup, _uniqueChannels(channels), message);
	return _messageListeners(publishTo, message, { target: channels, publish: true });
}

/**
 * Broadcast a message to the given listeners on the given channels.
 *
 * @param {Map} listenerLookup			The listener lookup to use.
 * @param {Array.<string>} channels		The channels to broadcast on.
 * @param {*} message					The broadcast message.
 * @returns {boolean}					Did any listeners receive the message.
 */
function _broadcast(listenerLookup, channels, message) {
	const broadcastTo = _getBroadcastTo(listenerLookup, channels, message);
	return _messageListeners(broadcastTo, message, { target: channels, broadcast: true });
}

/**
 * Take an input message of type similar to Message.  Based on it's content broadcast or publish to given
 * PubSub instance.
 *
 * @private
 * @param {Map} listenerLookup			The Pubsub instance.
 * @param {Message|Object} message		Message to mirror.
 * @returns {boolean}					Did anything receive the message?
 */
function _mirror(listenerLookup, message) {
	const channels = _getCorrectedChannelsArray(message.target);

	let mirrored = false;

	if (!message.data) message.data = {};
	if (!message.broadcast && !message.publish) message.publish = true;

	let mirrorTo;
	const options = { target: channels };

	if (message.broadcast === true) {
		mirrorTo = _getBroadcastTo(listenerLookup, channels, message.data);
		options.broadcast = true;
	} else if (message.publish === true) {
		mirrorTo = _getPublishTo(listenerLookup, _uniqueChannels(channels), message.data);
		options.publish = true;
	}
	if (mirrorTo && mirrorTo.size) {
		if (message.timestamp) options.timestamp = message.timestamp;
		mirrored = _messageListeners(mirrorTo, message.data, options) || mirrored;
	}

	return mirrored;
}

/**
 * Subscribe to the given channels with the supplied listener and filter. Will use the supplied listener lookup map to
 * set listeners.
 *
 * @private
 * @param {Map} listenerLookup										The listener lookup map.
 * @param {Array.<string|RegExp>|Set.<string|RegExp>} channels		The channels to subscribe to.
 * @param {Object} filter											The sift filter to use.
 * @param {Function} listener										The listener to fire when messages received.
 * @returns {Function}												Unsubscribe function.
 */
function _subscribe(listenerLookup, channels, filter, listener) {
	if (!isFunction(listener)) throw createError(TypeError, 'CallbackNotFunction');
	if (!isObject(filter)) throw createError(TypeError, 'FilterNotAnObject');
	if (!_allChannelsAreCorrectType(channels)) throw createError(TypeError, 'ChannelNotAString');

	const subscription = { listener, filter };
	_subscriptionsAction(listenerLookup, channels, 'add', subscription);
	return () => _subscriptionsAction(listenerLookup, channels, 'delete', subscription);
}

/**
 * Unsubscribe the given listener throughout this PubSub instance or if channel(s) given unsubscribe from the given
 * channel(s) through PubSub instance.
 *
 * @private
 * @method
 * @param {Map} listenerLookup										The listener lookup to use.
 * @param {Array.<string|Function|RegExp>} channelsOrListeners		The channel or listener to unsubscribe.
 * @return {boolean}												Did anything unsubscibe?
 */
function _unsubscribe(listenerLookup, channelsOrListeners) {
	let unsubscribed = false;

	channelsOrListeners.forEach(channel => {
		if (isFunction(channel)) {
			unsubscribed = _unsubscribeListener(listenerLookup, channel) || unsubscribed;
		} else {
			unsubscribed = _unsubscribeChannel(listenerLookup, channel) || unsubscribed;
		}
	});

	return unsubscribed;
}

/**
 * Publish and Subscription class.
 *
 * @public
 * @class
 */
class PubSub {
	constructor() {
		const emitterSourceOrder = this.emitterSourceOrder;
		emitterSourceOrder.add({ name: 'Generic', fromOptions: true, method: 'on' });
		emitterSourceOrder.add({ name: 'jQuery', fromOptions: false, method: 'on' });
		emitterSourceOrder.add({ name: 'Angular', fromOptions: false, method: '$on' });
		emitterSourceOrder.add({ name: 'PubSub', fromOptions: false, method: 'subscribe' });
		emitterSourceOrder.add({ name: 'DOM', fromOptions: false, method: 'addEventListener' });
	}

	/**
  * Subscribe to information published on a given channel(s) path with optional filtering. If a regular-expression is
  * given for a channel it will receive published data but not broadcast data.
  *
  * @public
  * @method
  * @param {string|RegExp|Array.<string|RegExp>|Set.<string|RegExp>} channel		Channel(s) to subscribe to
  * 																				(including glob-style patterns).
  * @param {Object} [filter={}]														Filter to filter-out messages that
  * 																				are not wanted.
  * @param {Function} listener													Listener for caught messages.
  * @returns {Function}															Unsubscribe function.
  */
	subscribe(channel, filter, listener) {
		return _subscribe(Private.get(this, 'channels', Map), makeArray(channel).map(channel => _removingTrailingSlash(channel)), listener ? filter : {}, listener ? listener : filter);
	}

	/**
  * Unsubscribe the given listener throughout this PubSub instance or if channel(s) given unsubscribe from the given
  * channel(s) through PubSub instance.
  *
  * @public
  * @method
  * @param {string|Function|RegExp|Array.<string|Function|RegExp>} channel	The channel or listener to unsubscribe.
  * @return {boolean}														Did anything unsubscibe?
  */
	unsubscribe(channel) {
		const channels = Private.get(this, 'channels', Map);
		return _unsubscribe(channels, makeArray(channel));
	}

	/**
  * Publish a message to the given channel(s). Publishing causes a message to be read on given channel and all
  * parent channels.
  *
  * @public
  * @method
  * @param {string|Array|set} channel		Channel(s) to publish on (including glob-style patterns).
  * @param {*} message						Message to publish.
  * @returns {boolean}						Did the message publish?
  */
	publish(channel, message) {
		return _publish(Private.get(this, 'channels', Map), _getCorrectedChannelsArray(channel), message);
	}

	/**
  * Broadcast a message to the given channel(s). Broadcasting causes a message to be read on given channel and all
  * descendant channels. Will not be read on channel subscriptions that are regular-expressions.
  *
  * @public
  * @method
  * @param {string|Array|set} channel		Channel(s) to publish on (including glob-style patterns).
  * @param {*} message						Message to publish.
  * @returns {boolean}						Did the message publish?
  */
	broadcast(channel, message) {
		return _broadcast(Private.get(this, 'channels', Map), _getCorrectedChannelsArray(channel), message);
	}

	/**
  * Mirror a message from on pubsub source into this instance.  It expects a message object in a similar format to
  * the one used in this class.  Messages do not have to be identical but they should have a target, which is the
  * channels to broadcast/publish to; a data property, which is the message; and either a publish or broadcast
  * boolean property.
  *
  * Parsers can be supplied to parse the message into the correct format. A base maybe supplied if we want to prepend
  * a new base to each channel.
  *
  * @note: Messages are mirrored not republished; original messages are cloned.
  *
  * @param {Message|Object|*} message			The message object to mirror.
  * @param {Array.<Function>} [parsers=[]]		The parsers to use in converting into the correct format.
  * @param {string} [base='']					The base to prepend to channels.
  * @returns {boolean}							Did anything receive the message?
  */
	mirror(message, parsers = [], base = '/') {
		return _mirror(Private.get(this, 'channels', Map), _mirrorMessageParse(message, parsers, base));
	}

	/**
  * Given a source emitter, mirror given events to this pubsub instance.  This is a convenience method, to easily
  * mirror events from the DOM, jQuery or Angular.  It covers most use cases and therefore makes it easier to just
  * plug another emitter into this PubSub class.
  *
  * Method can be called with options but without channel.  In this case the default channel of '/' is applied.
  *
  * @param {Object} emitter								The source emitter.
  * @param {string|Array.<string>|*} [channel='/']		The 'channel' to 'subscribe' on the emitter.
  * @param {Object} [options={}]							Options object for creating the mirror.
  */
	source(emitter, channel = '/', options = {}) {
		if (!isString(channel) && !Array.isArray(channel) && !(channel instanceof Set)) {
			if (isObject(options) && !Object.keys(options).length) {
				options = channel;
				channel = '/';
			}
		}

		if (options.type) {
			const sourceMirror = getSourceSubscriber(this, options.type);
			if (sourceMirror) return sourceMirror(this, emitter, channel, options);
		}

		[...this.emitterSourceOrder].every(details => {
			const method = details.fromOptions ? options[details.method] : details.method;
			if (emitter[method]) {
				const sourceMirror = getSourceSubscriber(this, details.name);
				if (sourceMirror) {
					sourceMirror(this, emitter, channel, options);
					return false;
				}
			}
			return true;
		});
	}

	addSourceSubscriber(name, method) {
		const sourceSubscribers = Private.get(this, 'sourceSubscribers', Map);
		sourceSubscribers.set(name, method);
	}

	deleteSourceSubscriber(name) {
		const sourceSubscribers = Private.get(this, 'sourceSubscribers', Map);
		sourceSubscribers.delete(name);
	}

	static addSourceSubscriber(name, method) {
		const sourceSubscribers = Private.get(PubSub, 'sourceSubscribers', Map);
		sourceSubscribers.set(name, method);
	}

	static deleteSourceSubscriber(name) {
		const sourceSubscribers = Private.get(PubSub, 'sourceSubscribers', Map);
		sourceSubscribers.delete(name);
	}

	get emitterSourceOrder() {
		return Private.get(this, 'emitterSourceOrder', Set);
	}
}

PubSub.addSourceSubscriber('jQuery', _sourceOn);
PubSub.addSourceSubscriber('Angular', _source$On);
PubSub.addSourceSubscriber('PubSub', _sourceSubscribe);
PubSub.addSourceSubscriber('DOM', _sourceAddEventListener);
PubSub.addSourceSubscriber('Generic', _sourceUserDefined);

//removeIf(browser)
module.exports = PubSub;
//endRemoveIf(browser)