/**
* Functionality to make the node a delegated event container
* @module node
* @submodule node-event-delegate
*/
/**
* <p>Sets up a delegation listener for an event occurring inside the Node.
* The delegated event will be verified against a supplied selector or
* filtering function to test if the event references at least one node that
* should trigger the subscription callback.</p>
*
* <p>Selector string filters will trigger the callback if the event originated
* from a node that matches it or is contained in a node that matches it.
* Function filters are called for each Node up the parent axis to the
* subscribing container node, and receive at each level the Node and the event
* object. The function should return true (or a truthy value) if that Node
* should trigger the subscription callback. Note, it is possible for filters
* to match multiple Nodes for a single event. In this case, the delegate
* callback will be executed for each matching Node.</p>
*
* <p>For each matching Node, the callback will be executed with its 'this'
* object set to the Node matched by the filter (unless a specific context was
* provided during subscription), and the provided event's
* <code>currentTarget</code> will also be set to the matching Node. The
* containing Node from which the subscription was originally made can be
* referenced as <code>e.container</code>.
*
* @method delegate
* @param type {String} the event type to delegate
* @param fn {Function} the callback function to execute. This function
* will be provided the event object for the delegated event.
* @param spec {String|Function} a selector that must match the target of the
* event or a function to test target and its parents for a match
* @param context {Object} optional argument that specifies what 'this' refers to.
* @param args* {any} 0..n additional arguments to pass on to the callback function.
* These arguments will be added after the event object.
* @return {EventHandle} the detach handle
* @for Node
*/
Y.Node.prototype.delegate = function(type) {
var args = Y.Array(arguments, 0, true),
index = (Y.Lang.isObject(type) && !Y.Lang.isArray(type)) ? 1 : 2;
args.splice(index, 0, this._node);
return Y.delegate.apply(Y, args);
};