/**
 * LavaLamp - A menu plugin for jQuery with cool hover effects.
 * @requires jQuery v1.1.3.1 or above
 *
 * http://gmarwaha.com/blog/?p=7
 *
 * Copyright (c) 2007 Ganeshji Marwaha (gmarwaha.com)
 * Dual licensed under the MIT and GPL licenses:
 * http://www.opensource.org/licenses/mit-license.php
 * http://www.gnu.org/licenses/gpl.html
 *
 * Version: 0.2.0
 * Requires Jquery 1.2.1 from version 0.2.0 onwards. 
 * For jquery 1.1.x, use version 0.1.0 of lavalamp
 */

/**
 * Creates a menu with an unordered list of menu-items. You can either use the CSS that comes with the plugin, or write your own styles 
 * to create a personalized effect
 *
 * The HTML markup used to build the menu can be as simple as...
 *
 *       <ul class="lavaLamp">
 *           <li><a href="#">Home</a></li>
 *           <li><a href="#">Plant a tree</a></li>
 *           <li><a href="#">Travel</a></li>
 *           <li><a href="#">Ride an elephant</a></li>
 *       </ul>
 *
 * Once you have included the style sheet that comes with the plugin, you will have to include 
 * a reference to jquery library, easing plugin(optional) and the LavaLamp(this) plugin.
 *
 * Use the following snippet to initialize the menu.
 *   $(function() { $(".lavaLamp").lavaLamp({ fx: "backout", speed: 700}) });
 *
 * Thats it. Now you should have a working lavalamp menu. 
 *
 * @param an options object - You can specify all the options shown below as an options object param.
 *
 * @option fx - default is "linear"
 * @example
 * $(".lavaLamp").lavaLamp({ fx: "backout" });
 * @desc Creates a menu with "backout" easing effect. You need to include the easing plugin for this to work.
 *
 * @option speed - default is 500 ms
 * @example
 * $(".lavaLamp").lavaLamp({ speed: 500 });
 * @desc Creates a menu with an animation speed of 500 ms.
 *
 * @option click - no defaults
 * @example
 * $(".lavaLamp").lavaLamp({ click: function(event, menuItem) { return false; } });
 * @desc You can supply a callback to be executed when the menu item is clicked. 
 * The event object and the menu-item that was clicked will be passed in as arguments.
 */
(function($) {
$.fn.lavaLamp = function(o) {
    o = $.extend({ fx: "linear", speed: 500, click: function(){} }, o || {});

    return this.each(function() {
        var me = $(this), noop = function(){},
            $back = $('<li class="back"><div class="left"></div></li>').appendTo(me),
            $li = $("li", this), curr = $("li.current", this)[0] || $($li[0]).addClass("current")[0];

        $li.not(".back").hover(function() {
            move(this);
        }, noop);

        $(this).hover(noop, function() {
            move(curr);
        });

        $li.click(function(e) {
            setCurr(this);
            return o.click.apply(this, [e, this]);
        });

        setCurr(curr);

        function setCurr(el) {
            $back.css({ "left": el.offsetLeft+"px", "width": el.offsetWidth+"px" });
            curr = el;
        };

        function move(el) {
            $back.each(function() {
                $(this).dequeue(); }
            ).animate({
                width: el.offsetWidth,
                left: el.offsetLeft
            }, o.speed, o.fx);
        };

    });
};
})(jQuery);


/*
 * jQuery Easing v1.1 - http://gsgd.co.uk/sandbox/jquery.easing.php
 *
 * Uses the built in easing capabilities added in jQuery 1.1
 * to offer multiple easing options
 *
 * Copyright (c) 2007 George Smith
 * Licensed under the MIT License:
 *   http://www.opensource.org/licenses/mit-license.php
 */

jQuery.easing = {
	easein: function(x, t, b, c, d) {
		return c*(t/=d)*t + b; // in
	},
	easeinout: function(x, t, b, c, d) {
		if (t < d/2) return 2*c*t*t/(d*d) + b;
		var ts = t - d/2;
		return -2*c*ts*ts/(d*d) + 2*c*ts/d + c/2 + b;		
	},
	easeout: function(x, t, b, c, d) {
		return -c*t*t/(d*d) + 2*c*t/d + b;
	},
	expoin: function(x, t, b, c, d) {
		var flip = 1;
		if (c < 0) {
			flip *= -1;
			c *= -1;
		}
		return flip * (Math.exp(Math.log(c)/d * t)) + b;		
	},
	expoout: function(x, t, b, c, d) {
		var flip = 1;
		if (c < 0) {
			flip *= -1;
			c *= -1;
		}
		return flip * (-Math.exp(-Math.log(c)/d * (t-d)) + c + 1) + b;
	},
	expoinout: function(x, t, b, c, d) {
		var flip = 1;
		if (c < 0) {
			flip *= -1;
			c *= -1;
		}
		if (t < d/2) return flip * (Math.exp(Math.log(c/2)/(d/2) * t)) + b;
		return flip * (-Math.exp(-2*Math.log(c/2)/d * (t-d)) + c + 1) + b;
	},
	bouncein: function(x, t, b, c, d) {
		return c - jQuery.easing['bounceout'](x, d-t, 0, c, d) + b;
	},
	bounceout: function(x, t, b, c, d) {
		if ((t/=d) < (1/2.75)) {
			return c*(7.5625*t*t) + b;
		} else if (t < (2/2.75)) {
			return c*(7.5625*(t-=(1.5/2.75))*t + .75) + b;
		} else if (t < (2.5/2.75)) {
			return c*(7.5625*(t-=(2.25/2.75))*t + .9375) + b;
		} else {
			return c*(7.5625*(t-=(2.625/2.75))*t + .984375) + b;
		}
	},
	bounceinout: function(x, t, b, c, d) {
		if (t < d/2) return jQuery.easing['bouncein'] (x, t*2, 0, c, d) * .5 + b;
		return jQuery.easing['bounceout'] (x, t*2-d,0, c, d) * .5 + c*.5 + b;
	},
	elasin: function(x, t, b, c, d) {
		var s=1.70158;var p=0;var a=c;
		if (t==0) return b;  if ((t/=d)==1) return b+c;  if (!p) p=d*.3;
		if (a < Math.abs(c)) { a=c; var s=p/4; }
		else var s = p/(2*Math.PI) * Math.asin (c/a);
		return -(a*Math.pow(2,10*(t-=1)) * Math.sin( (t*d-s)*(2*Math.PI)/p )) + b;
	},
	elasout: function(x, t, b, c, d) {
		var s=1.70158;var p=0;var a=c;
		if (t==0) return b;  if ((t/=d)==1) return b+c;  if (!p) p=d*.3;
		if (a < Math.abs(c)) { a=c; var s=p/4; }
		else var s = p/(2*Math.PI) * Math.asin (c/a);
		return a*Math.pow(2,-10*t) * Math.sin( (t*d-s)*(2*Math.PI)/p ) + c + b;
	},
	elasinout: function(x, t, b, c, d) {
		var s=1.70158;var p=0;var a=c;
		if (t==0) return b;  if ((t/=d/2)==2) return b+c;  if (!p) p=d*(.3*1.5);
		if (a < Math.abs(c)) { a=c; var s=p/4; }
		else var s = p/(2*Math.PI) * Math.asin (c/a);
		if (t < 1) return -.5*(a*Math.pow(2,10*(t-=1)) * Math.sin( (t*d-s)*(2*Math.PI)/p )) + b;
		return a*Math.pow(2,-10*(t-=1)) * Math.sin( (t*d-s)*(2*Math.PI)/p )*.5 + c + b;
	},
	backin: function(x, t, b, c, d) {
		var s=1.70158;
		return c*(t/=d)*t*((s+1)*t - s) + b;
	},
	backout: function(x, t, b, c, d) {
		var s=1.70158;
		return c*((t=t/d-1)*t*((s+1)*t + s) + 1) + b;
	},
	backinout: function(x, t, b, c, d) {
		var s=1.70158;
		if ((t/=d/2) < 1) return c/2*(t*t*(((s*=(1.525))+1)*t - s)) + b;
		return c/2*((t-=2)*t*(((s*=(1.525))+1)*t + s) + 2) + b;
	},
	linear: function(x, t, b, c, d) {
		return c*t/d + b; //linear
	}
};
