/**
 * @author Alexandre Magno
 * @desc Center a element with jQuery
 * @version 1.0
 * @example
 * $("element").center({
 *
 * 		vertical: true,
 *      horizontal: true
 *
 * });
 * @obs With no arguments, the default is above
 * @license free
 * @param bool vertical, bool horizontal
 * @contribution Paulo Radichi
 *
 */
jQuery.fn.center = function(params) {
var options = {
vertical: true,
horizontal: true
}
op = jQuery.extend(options, params);
   return this.each(function(){
//initializing variables
var $self = jQuery(this);
//get the dimensions using dimensions plugin
var width = $self.width();
var height = $self.height();
//get the paddings
var paddingTop = parseInt($self.css("padding-top"));
var paddingBottom = parseInt($self.css("padding-bottom"));
//get the borders
var borderTop = parseInt($self.css("border-top-width"));
var borderBottom = parseInt($self.css("border-bottom-width"));
//get the media of padding and borders
var mediaBorder = (borderTop+borderBottom)/2;
var mediaPadding = (paddingTop+paddingBottom)/2;
//get the type of positioning
var positionType = $self.parent().css("position");
// get the half minus of width and height
var halfWidth = (width/2)*(-1);
var halfHeight = ((height/2)*(-1))-mediaPadding-mediaBorder;
// initializing the css properties
var cssProp = {
position: 'absolute'
};
if(op.vertical) {
cssProp.height = height;
cssProp.top = '50%';
cssProp.marginTop = halfHeight;
}
if(op.horizontal) {
cssProp.width = width;
cssProp.left = '50%';
cssProp.marginLeft = halfWidth;
}
//check the current position
if(positionType == 'static') {
$self.parent().css("position","relative");
}
//aplying the css
$self.css(cssProp);
   });
};