pubsub

eventsystem.js

var eventsystem = (function (eventsystem) {
	var topics = {};

	eventsystem = eventsystem || {
		subscribe: function (topic, listener) {
			// Create the topic's object if not yet created
			if (!topics[topic]) topics[topic] = { queue: [] };

			// Add the listener to queue
			var index = topics[topic].queue.push(listener) - 1;

			// Provide handle back for removal of topic
			return {
				remove: function () {
					delete topics[topic].queue[index];
				}
			};
		},
		publish: function (topic, info) {
			// If the topic doesn't exist, or there's no listeners in queue, just leave
			if (!topics[topic] || !topics[topic].queue.length) return;

			// Cycle through topics queue, fire!
			var items = topics[topic].queue;
			items.forEach(function (item) {
				item(info || {});
			});
		}
	};

	return eventsystem;
})(eventsystem);