Custom node.js event emitter class

icevents.js

class IcyEmitter {
	constructor() {
		this.listeners = {};
		this.on = this.addEventListener;
	}

	emitAll(event) {
		for(let a in this.listeners) {
			let scopes = this.listeners[a];
			for(let b in scopes) {
				let listener = scopes[b];
				if(listener.event == event)
					listener.callback.apply(null, Array.prototype.slice.call(arguments, 1));

				if(listener.once == true)
					this.removeListeners(event, listener.scope);
			}
		}
	}

	removeAll(event) {
		for(let a in this.listeners) {
			let scopes = this.listeners[a];
			for(let b in scopes) {
				let listener = scopes[b];
				if(listener.event == event)
					this.removeListeners(listener.event, a);
			}
		}
	}

	emitScope(event, scope) {
		if(!this.listeners[scope]) return;
		for(let a in this.listeners[scope]) {
			let listener = this.listeners[scope][a];
			if(listener.event == event)
				listener.callback.apply(null, Array.prototype.slice.call(arguments, 2));

			if(listener.once == true)
				this.removeListeners(event, scope);
		}
	}

	removeListeners(event, scope) {
		if(!this.listeners[scope]) return;
		for(let a in this.listeners[scope]) {
			let listener = this.listeners[scope][a];
			if(listener.event == event) 
				this.listeners[scope].splice(this.listeners[scope].indexOf(listener), 1);
		}
	}

	removeListener(event, scope, callback) {
		if(!this.listeners[scope]) return;
		for(let a in this.listeners[scope]) {
			let listener = this.listeners[scope][a];
			if(listener.event == event && listener.callback == callback) 
				this.listeners[scope].splice(this.listeners[scope].indexOf(listener), 1);
		}
	}

	removeScope(scope) {
		if(!this.listeners[scope]) return;
		this.listeners[scope] = [];
		delete this.listeners[scope];
	}

	addEventListener(event, scope, callback) {
		if(!this.listeners[scope])
			this.listeners[scope] = [];

		this.listeners[scope].push({event: event, callback: callback, once: false});
	}

	once(event, scope, callback) {
		if(!this.listeners[scope])
			this.listeners[scope] = [];

		this.listeners[scope].push({event: event, callback: callback, once: true});
	}
}

module.exports = {
	IcyEmitter: IcyEmitter
}