/**
* <p>Adds subscription and delegation support for mouseenter and mouseleave
* events. Unlike mouseover and mouseout, these events aren't fired from child
* elements of a subscribed node.</p>
*
* <p>This avoids receiving three mouseover notifications from a setup like</p>
*
* <pre><code>div#container > p > a[href]</code></pre>
*
* <p>where</p>
*
* <pre><code>Y.one('#container').on('mouseover', callback)</code></pre>
*
* <p>When the mouse moves over the link, one mouseover event is fired from
* #container, then when the mouse moves over the p, another mouseover event is
* fired and bubbles to #container, causing a second notification, and finally
* when the mouse moves over the link, a third mouseover event is fired and
* bubbles to #container for a third notification.</p>
*
* <p>By contrast, using mouseenter instead of mouseover, the callback would be
* executed only once when the mouse moves over #container.</p>
*
* @module event
* @submodule event-mouseenter
*/
var domEventProxies = Y.Env.evt.dom_wrappers,
contains = Y.DOM.contains,
toArray = Y.Array,
noop = function () {},
config = {
proxyType: "mouseover",
relProperty: "fromElement",
_notify: function (e, property, notifier) {
var el = this._node,
related = e.relatedTarget || e[property];
if (el !== related && !contains(el, related)) {
notifier.fire(new Y.DOMEventFacade(e, el,
domEventProxies['event:' + Y.stamp(el) + e.type]));
}
},
on: function (node, sub, notifier) {
var el = Y.Node.getDOMNode(node),
args = [
this.proxyType,
this._notify,
el,
null,
this.relProperty,
notifier];
sub.handle = Y.Event._attach(args, { facade: false });
// node.on(this.proxyType, notify, null, notifier);
},
detach: function (node, sub) {
sub.handle.detach();
},
delegate: function (node, sub, notifier, filter) {
var el = Y.Node.getDOMNode(node),
args = [
this.proxyType,
noop,
el,
null,
notifier
];
sub.handle = Y.Event._attach(args, { facade: false });
sub.handle.sub.filter = filter;
sub.handle.sub.relProperty = this.relProperty;
sub.handle.sub._notify = this._filterNotify;
},
_filterNotify: function (thisObj, args, ce) {
args = args.slice();
if (this.args) {
args.push.apply(args, this.args);
}
var currentTarget = Y.delegate._applyFilter(this.filter, args, ce),
related = args[0].relatedTarget || args[0][this.relProperty],
e, i, len, ret, ct;
if (currentTarget) {
currentTarget = toArray(currentTarget);
for (i = 0, len = currentTarget.length && (!e || !e.stopped); i < len; ++i) {
ct = currentTarget[0];
if (!contains(ct, related)) {
if (!e) {
e = new Y.DOMEventFacade(args[0], ct, ce);
e.container = Y.one(ce.el);
}
e.currentTarget = Y.one(ct);
// TODO: where is notifier? args? this.notifier?
ret = args[1].fire(e);
if (ret === false) {
break;
}
}
}
}
return ret;
},
detachDelegate: function (node, sub) {
sub.handle.detach();
}
};
Y.Event.define("mouseenter", config, true);
Y.Event.define("mouseleave", Y.merge(config, {
proxyType: "mouseout",
relProperty: "toElement"
}), true);