(function () {
    function form2httpAuth () {
        /* Skip if the browser indicates it does this itself. */
        if (document.implementation &&
            document.implementation.hasFeature &&
            document.implementation.hasFeature("HTTPFormAuth", "1.0"))
            return true;

        /* Attempt login with provided credentials. */
        var username = this.username.value;
        var password = this.password.value;
        var authed = false;
        var form = this;
        $.ajax({
            url: "/ajax-login.php",
            /* synchronous hangs some browsers temporarily. :/ */
            async: false,
            global: false,
            username: username,
            password: password,
            dataType: 'text',
            success: function (data, status, xhr) {
                authed = true;
            },
            error: function (xhr, status, err) {
                authed = false;
            },
            complete: function (xhr, status) {
                /* Don't send username and password if we successfully managed to auth via HTTP */
                if (authed) {
                    form.username.parentNode.removeChild(form.username);
                    form.password.parentNode.removeChild(form.password);
                }
            }
        });

        /* This is the only way to get browsers to submit the form exactly as
           the user did, which is why we aren't using async above. */
        return true;
    }

    $("form.http-authentication").submit(form2httpAuth);
})();