/*-------------------------------------------------------------------- 
 * JQuery Plugin: "EqualHeights"
 * by:  Scott Jehl, Todd Parker, Maggie Costello Wachs (http://www.filamentgroup.com)
 *
 * Copyright (c) 2008 Filament Group
 * Licensed under GPL (http://www.opensource.org/licenses/gpl-license.php)
 *
 * Description: Compares the heights or widths of the top-level children of a provided element 
                and sets their min-height to the tallest height (or width to widest width). Sets in em units 
                by default if pxToEm() method is available.
 * Dependencies: jQuery library, pxToEm method  (article: 
                http://www.filamentgroup.com/lab/retaining_scalable_interfaces_with_pixel_to_em_conversion/)                                                      
 * Usage Example: $(element).equalHeights();
                Optional: to set min-height in px, pass a true argument: $(element).equalHeights(true);
 * Version: 2.0, 08.01.2008
--------------------------------------------------------------------*/

$.fn.equalHeights = function(selector) {
        $(this).each(function(){
                var currentTallest = 0;
                $(this).children().each(function(i){
                        if ($(this).height() > currentTallest) { currentTallest = $(this).height(); }
                });
                currentTallest = currentTallest.pxToEm(); //use ems unless px is specified
                // for ie6, set height since min-height isn't supported
                if ($.browser.msie) { $(this).children(selector).css({'height': currentTallest}); }
                $(this).children(selector).css({'min-height': currentTallest}); 
        });
        return this;
};

$.fn.toEm = function(settings){
        settings = jQuery.extend({
                scope: 'body'
        }, settings);
        var that = parseInt(this[0],10);
        var scopeTest = jQuery('<div style="display: none; font-size: 1em; margin: 0; padding:0; height: auto; line-height: 1; border:0;">&nbsp;</div>').appendTo(settings.scope);
        var scopeVal = scopeTest.height();
        scopeTest.remove();
        return (that / scopeVal).toFixed(8) + 'em';
};


$.fn.toPx = function(settings){
        settings = jQuery.extend({
                scope: 'body'
        }, settings);
        var that = parseFloat(this[0]);
        var scopeTest = jQuery('<div style="display: none; font-size: 1em; margin: 0; padding:0; height: auto; line-height: 1; border:0;">&nbsp;</div>').appendTo(settings.scope);
        var scopeVal = scopeTest.height();
        scopeTest.remove();
        return Math.round(that * scopeVal) + 'px';
};

Number.prototype.pxToEm = String.prototype.pxToEm = function(settings){
        //set defaults
        settings = jQuery.extend({
                scope: 'body',
                reverse: false
        }, settings);
        
        var pxVal = (this == '') ? 0 : parseFloat(this);
        var scopeVal;
        var getWindowWidth = function(){
                var de = document.documentElement;
                return self.innerWidth || (de && de.clientWidth) || document.body.clientWidth;
        };      
        
        /* When a percentage-based font-size is set on the body, IE returns that percent of the window width as the font-size. 
                For example, if the body font-size is 62.5% and the window width is 1000px, IE will return 625px as the font-size.      
                When this happens, we calculate the correct body font-size (%) and multiply it by 16 (the standard browser font size) 
                to get an accurate em value. */
                                
        if (settings.scope == 'body' && $.browser.msie && (parseFloat($('body').css('font-size')) / getWindowWidth()).toFixed(1) > 0.0) {
                var calcFontSize = function(){          
                        return (parseFloat($('body').css('font-size'))/getWindowWidth()).toFixed(3) * 16;
                };
                scopeVal = calcFontSize();
        }
        else { scopeVal = parseFloat(jQuery(settings.scope).css("font-size")); };
                        
        var result = (settings.reverse == true) ? (pxVal * scopeVal).toFixed(2) + 'px' : (pxVal / scopeVal).toFixed(2) + 'em';
        return result;
};