/**
+ * Adds focus and blur event listener support. These events normally
+ * do not bubble, so this adds support for that so these events
+ * can be used in event delegation scenarios.
+ *
+ * @module event
+ * @submodule event-focus
+ */
+(function() {
+
+var UA = Y.UA,
+ Event = Y.Event,
+ plugins = Y.Env.evt.plugins,
+ ie = UA.ie,
+ bUseMutation = (UA.opera || UA.webkit),
+ eventNames = {
+ focus: (ie ? 'focusin' : (bUseMutation ? 'DOMFocusIn' : 'focus')),
+ blur: (ie ? 'focusout' : (bUseMutation ? 'DOMFocusOut' : 'blur'))
+ },
+
+ // Only need to use capture phase for Gecko since it doesn't support
+ // focusin, focusout, DOMFocusIn, or DOMFocusOut
+ CAPTURE_CONFIG = { capture: (UA.gecko ? true : false) },
+
+
+ attach = function (args, config) {
+
+ var a = Y.Array(args, 0, true);
+ a[0] = eventNames[a[0]];
+ return Event._attach(a, config);
+
+ },
+
+ eventAdapter = {
+
+ on: function () {
+ return attach(arguments, CAPTURE_CONFIG);
+ }
+
+ };
+
+
+Event._attachFocus = attach;
+Event._attachBlur = attach;
+
+/**
+ * Adds a DOM focus listener. Uses the focusin event in IE,
+ * DOMFocusIn for Opera and Webkit, and the capture phase for Gecko so that
+ * the event propagates in a way that enables event delegation.
+ *
+ * @for YUI
+ * @event focus
+ * @param type {string} 'focus'
+ * @param fn {function} the callback function to execute
+ * @param o {string|HTMLElement|collection} the element(s) to bind
+ * @param context optional context object
+ * @param args 0..n additional arguments to provide to the listener.
+ * @return {EventHandle} the detach handle
+ */
+plugins.focus = eventAdapter;
+
+/**
+ * Adds a DOM blur listener. Uses the focusout event in IE,
+ * DOMFocusOut for Opera and Webkit, and the capture phase for Gecko so that
+ * the event propagates in a way that enables event delegation.
+ *
+ * @for YUI
+ * @event blur
+ * @param type {string} 'blur'
+ * @param fn {function} the callback function to execute
+ * @param o {string|HTMLElement|collection} the element(s) to bind
+ * @param context optional context object
+ * @param args 0..n additional arguments to provide to the listener.
+ * @return {EventHandle} the detach handle
+ */
+plugins.blur = eventAdapter;
+
+})();
+