Possible form validation autothing

gistfile1.js

(function($){

    $.fn.observeRequirements = function(fnRequirementsMet, fnRequirementsUnmet) {
        fnRequirementsMet   = fnRequirementsMet   || function(){}; // Empty fns may not be necessary
        fnRequirementsUnmet = fnRequirementsUnmet || function(){};

        var $wrappers = $(this); // I do this to help distinguish `this` once things get nesty
        var requirementsMet = true;

        $wrappers.each(function(){ // .each to support operating on element collections
            var $wrapper = $(this);
            $wrapper.find('*:required:not(:disabled)').each(function(){ // this selector may not work, I dunno
                var $element = $(this);
                switch ($element.get(0).nodeName.toLowerCase()) {
                    case 'input': // not sure i'm properly nesting ifs within a case, sorry
                        if ($element.attr('type').toLowerCase() == 'text' || $element.attr('type').toLowerCase() == 'password' || $element.attr('type').toLowerCase() == 'hidden') {
                            $element.on('keypress', function(){
                                if (!$element.val() != '')
                                    requirementsMet = false;
                            });
                        }
                        else if ($element.attr('type').toLowerCase() == 'radio' || $element.attr('type').toLowerCase() == 'checkbox') {
                            $element.on('change', function(){
                                if (!$element.prop('checked'))
                                    requirementsMet = false;
                            });
                        }
                        break;
                    case 'textarea':
                        $element.on('keypress', function(){
                            if (!$element.val()) // this may not be how you check textareas
                                requirementsMet = false;
                        });
                        break;
                    case 'select':
                        $element.on('change', function(){
                            if (!$element.val()) // this may not be how you check selects
                                requirementsMet = false;
                        });
                        break;
                }
            });
        });

        if (requirementsMet)
            fnRequirementsMet;
        else
            fnRequirementsUnmet;

        return $wrappers;
    };

})(this.jQuery);

$('#my_form').observeRequirements(function(){
    $("#save_new_type").attr('disabled', false);
}, function(){
    $("#save_new_type").attr('disabled', true);
});