(function($) {
    $.fn.extend({abModal: function(options) {
            var defaults = {top: 100, overlay: 0.5, closeButton: null};
            var overlay = $("<div id='anti_block_overlay'></div>");
            $("body").append(overlay);
            options = $.extend(defaults, options);

            var o = options;
            var modal_id = this;

            $(o.closeButton).click(function() {
                close_modal(modal_id);
            });
            var modal_width = $(modal_id).outerWidth();
            $("#anti_block_overlay").css({"display": "block", opacity: 0});
            $("#anti_block_overlay").fadeTo(200, o.overlay);
            $(modal_id).css({"display": "block", "position": "fixed", "opacity": 0, "z-index": 11000, "left": 50 + "%", "margin-left": -(modal_width / 2) + "px", "top": o.top + "px"});
            $(modal_id).fadeTo(200, 1);

            function close_modal(modal_id) {
                $("#anti_block_overlay").fadeOut(200);
                $(modal_id).css({"display": "none"});
            }}
    });
})(jQuery);