/*

 * stickyfloat - jQuery plugin for verticaly floating anything in a constrained area

 * 

 * Example: jQuery('#menu').stickyfloat({duration: 400});

 * parameters:

 * 		duration 	- the duration of the animation

 *		startOffset - the amount of scroll offset after it the animations kicks in

 *		offsetY		- the offset from the top when the object is animated

 *		lockBottom	- 'true' by default, set to false if you don't want your floating box to stop at parent's bottom

 * jQueryVersion: 05.16.2009 r1

 * Copyright (c) 2009 Yair Even-Or

 * vsync.design@gmail.com

 */



(function( $ ){



$.fn.stickyfloat = function(options, lockBottom) {

				var $obj 				= this;

				var parentPaddingTop 	= parseInt($obj.parent().css('padding-top'));

				var startOffset 		= $obj.parent().offset().top;

				var opts 				= $.extend({ startOffset: startOffset, offsetY: parentPaddingTop, duration: 200, lockBottom:true }, options);

				

				$obj.css({ position: 'absolute' });

				

				if(opts.lockBottom){

					var bottomPos = $obj.parent().height() - $obj.height() + parentPaddingTop; //get the maximum scrollTop value

					if( bottomPos < 0 )

						bottomPos = 0;

				}

				

				$(window).scroll(function () { 

					$obj.stop(); // stop all calculations on scroll event



					var pastStartOffset			= $(document).scrollTop() > opts.startOffset;	// check if the window was scrolled down more than the start offset declared.

					var objFartherThanTopPos	= $obj.offset().top > startOffset;	// check if the object is at it's top position (starting point)

					var objBiggerThanWindow 	= $obj.outerHeight() < $(window).height();	// if the window size is smaller than the Obj size, then do not animate.

					

					// if window scrolled down more than startOffset OR obj position is greater than

					// the top position possible (+ offsetY) AND window size must be bigger than Obj size

					if( (pastStartOffset || objFartherThanTopPos) && objBiggerThanWindow ){ 

						var newpos = ($(document).scrollTop() -startOffset + opts.offsetY );

						if ( newpos > bottomPos )

							newpos = bottomPos;

						if ( $(document).scrollTop() < opts.startOffset ) // if window scrolled < starting offset, then reset Obj position (opts.offsetY);

							newpos = parentPaddingTop;

			

						$obj.animate({ top: newpos }, opts.duration );

					}

				});

			};

		  })( jQuery );