eventhanlder.js

var referenceToEventListeners = {},
    etid = 0;

function getTargetIdFromTarget(target) {
    target = target || document;
    var targetId = target.id;
    if (!targetId) {
        targetId = 'Element' + ++etid;
        target.id = targetId;
    }
    return targetId;
}

function capture (event, handler, target) {
    var targetId = getTargetIdFromTarget(target);
    if (!referenceToEventListeners[event]) {
        referenceToEventListeners[event] = {};
    }
    if (!referenceToEventListeners[event][targetId]) {
        referenceToEventListeners[event][targetId] = {};
    }
    referenceToEventListeners[event][targetId].push(handler);
}

function dispatch (event, data, target) {
    if (referenceToEventListeners[event]) {
        var targetId = getTargetIdFromTarget(target), eventArgs;
        if (referenceToEventListeners[event][targetId]) {
            eventArgs = {
                eventName: event,
                eventData: data || null
            };
            referenceToEventListeners[event][targetId].forEach(function (handler) {
                handler(eventArgs);
            });
        }
    }
}