var module = angular.module('App');

module.factory('Stream', () => {

class Stream {

constructor() {

this.listeners = [];

this.children = [];

}

listen(listener) {

this.listeners.push(listener);

// unsubscriber

return () => {

this.listeners.splice( this.listeners.indexOf(listener), 1 );

};

}

push(data) {

// allow listeners to modify the data (use sparingly)

let changeData = (newValue) => data = newValue;

for (let listener in this.listeners) {

data = this.listeners[listener](data, changeData) || data;

}

for (let childStream in this.children) {

this.children[childStream].push(data);

}

}

destroy() {

this.listeners = [];

this.children = [];

}

// Events from this stream will then go into the passed stream

child(stream) {

this.children.push(stream);

// unsubscriber

return () => {

this.children.splice( this.children.indexOf(stream), 1 );

};

}

}

return Stream;

});