text: ﻿/**
  * hoverIntent is similar to jQuery's built-in "hover" function except that
  * instead of firing the onMouseOver event immediately, hoverIntent checks
  * to see if the user's mouse has slowed down (beneath the sensitivity
  * threshold) before firing the onMouseOver event.
  * 
  * hoverIntent r5 // 2007.03.27 // jQuery 1.1.2+
  * <http://cherne.net/brian/resources/jquery.hoverIntent.html>
  * 
  * hoverIntent is currently available for use in all personal or commercial 
  * projects under both MIT and GPL licenses. This means that you can choose 
  * the license that best suits your project, and use it accordingly.
  * 
  * // basic usage (just like .hover) receives onMouseOver and onMouseOut functions
  * $("ul li").hoverIntent( showNav , hideNav );
  * 
  * // advanced usage receives configuration object only
  * $("ul li").hoverIntent({
  *	sensitivity: 7, // number = sensitivity threshold (must be 1 or higher)
  *	interval: 100,   // number = milliseconds of polling interval
  *	over: showNav,  // function = onMouseOver callback (required)
  *	timeout: 0,   // number = milliseconds delay before onMouseOut function call
  *	out: hideNav    // function = onMouseOut callback (required)
  * });
  * 
  * @param  f  onMouseOver function || An object with configuration options
  * @param  g  onMouseOut function  || Nothing (use configuration options object)
  * @author    Brian Cherne <brian@cherne.net>
  */
  (function($) {
  	$.fn.hoverIntent = function(f,g) {
  		// default configuration options
  		var cfg = {
  			sensitivity: 7,
  			interval: 100,
  			timeout: 0
  		};
  		// override configuration options with user supplied object
  		cfg = $.extend(cfg, g ? { over: f, out: g } : f );
  
  		// instantiate variables
  		// cX, cY = current X and Y position of mouse, updated by mousemove event
  		// pX, pY = previous X and Y position of mouse, set by mouseover and polling interval
  		var cX, cY, pX, pY;
  
  		// A private function for getting mouse position
  		var track = function(ev) {
  			cX = ev.pageX;
  			cY = ev.pageY;
  		};
  
  		// A private function for comparing current and previous mouse position
  		var compare = function(ev,ob) {
  			ob.hoverIntent_t = clearTimeout(ob.hoverIntent_t);
  			// compare mouse positions to see if they've crossed the threshold
  			if ( ( Math.abs(pX-cX) + Math.abs(pY-cY) ) < cfg.sensitivity ) {
  				$(ob).unbind("mousemove",track);
  				// set hoverIntent state to true (so mouseOut can be called)
  				ob.hoverIntent_s = 1;
  				return cfg.over.apply(ob,[ev]);
  			} else {
  				// set previous coordinates for next time
  				pX = cX; pY = cY;
  				// use self-calling timeout, guarantees intervals are spaced out properly (avoids JavaScript timer bugs)
  				ob.hoverIntent_t = setTimeout( function(){compare(ev, ob);} , cfg.interval );
  			}
  		};
  
  		// A private function for delaying the mouseOut function
  		var delay = function(ev,ob) {
  			ob.hoverIntent_t = clearTimeout(ob.hoverIntent_t);
  			ob.hoverIntent_s = 0;
  			return cfg.out.apply(ob,[ev]);
  		};
  
  		// A private function for handling mouse 'hovering'
  		var handleHover = function(e) {
  			// next three lines copied from jQuery.hover, ignore children onMouseOver/onMouseOut
  			var p = (e.type == "mouseover" ? e.fromElement : e.toElement) || e.relatedTarget;
  			while ( p && p != this ) { try { p = p.parentNode; } catch(e) { p = this; } }
  			if ( p == this ) { return false; }
  
  			// copy objects to be passed into t (required for event object to be passed in IE)
  			var ev = jQuery.extend({},e);
  			var ob = this;
  
  			// cancel hoverIntent timer if it exists
  			if (ob.hoverIntent_t) { ob.hoverIntent_t = clearTimeout(ob.hoverIntent_t); }
  
  			// else e.type == "onmouseover"
  			if (e.type == "mouseover") {
  				// set "previous" X and Y position based on initial entry point
  				pX = ev.pageX; pY = ev.pageY;
  				// update "current" X and Y position based on mousemove
  				$(ob).bind("mousemove",track);
  				// start polling interval (self-calling timeout) to compare mouse coordinates over time
  				if (ob.hoverIntent_s != 1) { ob.hoverIntent_t = setTimeout( function(){compare(ev,ob);} , cfg.interval );}
  
  			// else e.type == "onmouseout"
  			} else {
  				// unbind expensive mousemove event
  				$(ob).unbind("mousemove",track);
  				// if hoverIntent state is true, then call the mouseOut function after the specified delay
  				if (ob.hoverIntent_s == 1) { ob.hoverIntent_t = setTimeout( function(){delay(ev,ob);} , cfg.timeout );}
  			}
  		};
  
  		// bind the function to the two event listeners
  		return this.mouseover(handleHover).mouseout(handleHover);
  	};
  })(jQuery);