Add min date to Umbraco forms validation

umbracoforms.js

(function ($) {

    if ($.validator != undefined) {

        $.validator.setDefaults({
            ignore: ":hidden"
        });

        $.validator.unobtrusive.adapters.addBool("requiredcb", "required");

        $.validator.addMethod('umbracoforms_selectonefromlist', function(value, element) {
            var valid = false;
            $("input", $(element).closest(".checkboxlist, .radiobuttonlist")).each(function(i) {
                if ($(this).is(':checked')) {
                    valid = true;
                }
            });
            return valid;
        });

        $.validator.unobtrusive.adapters.addBool("requiredlist", "umbracoforms_selectonefromlist");

        $.validator.addMethod('umbracoforms_regex', function(value, element) {

            var regex = $(element).attr("data-regex");
            var val = $(element).val();
            if (val.length == 0) {
                return true;
            }
            return val.match(regex);
        });

        $.validator.unobtrusive.adapters.addBool("regex", "umbracoforms_regex");
        
      //Custom code
      $.validator.addMethod('umbracoforms_mindate', function(value, element) {
            var valid = false;
           //min date checke
            return valid;
        });
       $.validator.unobtrusive.adapters.addBool("date", "umbracoforms_mindate");
      //End custom code
        $('.contour input[type=submit]').not('.cancel').click(function (evt) {
            evt.preventDefault();
            var self = $(this);
            var frm = self.closest('form');
            frm.validate();
            if (frm.valid()) {
                frm.submit();
                self.attr('disabled', 'disabled');

            }
        });
    }
} (jQuery));