/*
* stickyfloat - jQuery plugin for verticaly floating anything in a constrained area
* 
* Example: jQuery('#menu').stickyfloat({duration: 400});
* parameters:
* 		duration 	(200)	 - the duration of the animation
*		startOffset (number) - the amount of scroll offset after the animations kicks in
*		offsetY		(number) - the offset from the top when the object is animated
*		lockBottom	(true)	 - set to false if you don't want your floating box to stop at parent's bottom
*		delay		(0)		 - delay in milliseconds  until the animnations starts
easing		(linear) - easing function (jQuery has by default only 'swing' & 'linear')
* $Version: 08.10.2011 r2
* $Version: 05.16.2009 r1
* Copyright (c) 2009 Yair Even-Or
* vsync.design@gmail.com
*/
(function ($)
{   
    $.fn.stickyfloat = function (options, lockBottom)
    {
        var windowHeight = $(document).height()
        var $obj = this,
			doc = $(document),
			opts, bottomPos, pastStartOffset, objFartherThanTopPos, objBiggerThanWindow, newpos, checkTimer, lastDocPos = doc.scrollTop(),
			parentPaddingTop = $(window).height()-80; // parseInt($obj.parent().css('padding-top')),
            startOffset = $obj.parent().offset().top;

        $.extend($.fn.stickyfloat.opts, options, { startOffset: startOffset, offsetY: parentPaddingTop });
        opts = $.fn.stickyfloat.opts;
        $obj.css({ position: 'absolute' });

        if (opts.lockBottom)
        {
            bottomPos = $obj.parent().height(); // - $obj.outerHeight() +parentPaddingTop; //get the maximum scrollTop value
            if (bottomPos < 0)
                bottomPos = 0;
        }

        function checkScroll()
        {
            if (opts.duration > 40)
            {
                clearTimeout(checkTimer);
                checkTimer = setTimeout(function ()
                {
                    if (Math.abs(doc.scrollTop() - lastDocPos) > 0)
                    {
                        lastDocPos = doc.scrollTop();
                        initFloat();
                    }
                }, 40);
            }
            else initFloat();
        }

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

            pastStartOffset = doc.scrollTop() > opts.startOffset; // check if the window was scrolled down more than the start offset declared.
            objFartherThanTopPos = $obj.offset().top > startOffset; // check if the object is at it's top position (starting point)
            objBiggerThanWindow = $obj.outerHeight() < $(window).height(); // if the window size is smaller than the Obj size, then do not animate.
            contentBiggerThanWindow = $("#wrapper").outerHeight() > $(window).height();

            //alert($obj.outerHeight() + " " + $(window).height());

            // 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 && contentBiggerThanWindow)
            {
                newpos = (doc.scrollTop() - startOffset + opts.offsetY);
                //alert(doc.scrollTop() + " " + startOffset + " " + opts.offsetY);
                if (newpos > bottomPos)
                    newpos = bottomPos;
                if (doc.scrollTop() < opts.startOffset) // if window scrolled < starting offset, then reset Obj position (opts.offsetY);
                    newpos = parentPaddingTop;

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

        $(window).scroll(checkScroll);
        initFloat();
    };

    $.fn.stickyfloat.opts = { duration: 200, lockBottom: true, delay: 0, easing: 'linear' };
    
})(jQuery);