/**
* @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);

    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);


    });

};