KnockoutJS BlockUI-binding

Blocking elements with simple bindings.

HTML

<script src="//cdn.jsdelivr.net/knockout/3.3.0/knockout.js"></script>
<script src="//cdn.jsdelivr.net/jquery.blockui/2.70.0/jquery.blockUI.min.js"></script>
<button data-bind="click: function(){isBlocked(!isBlocked())}, text: isBlocked()?'unblock':'block'">block</button>
<br>
<br>
<div data-bind="blockUI: isBlocked">Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</div>
<br>
<br>
<table border=1 data-bind="blockUI: isBlocked">
    <tr>
        <td>block me</td>
        <td>block me</td>
        <td>block me</td>
    </tr>
    <tr>
        <td>block me</td>
        <td>block me</td>
        <td>block me</td>
    </tr>
    <tr>
        <td>block me</td>
        <td>block me</td>
        <td>block me</td>
    </tr>
</table>
<br>
<br>
<table border=1>
    <tbody>
        <tr>
            <td data-bind="blockUI: isBlocked">block me</td>
            <td>don't block me</td>
            <td>don't block me</td>
        </tr>
        <tr>
            <td>don't block me</td>
            <td>don't block me</td>
            <td>don't block me</td>
        </tr>
        <tr>
            <td>don't block me</td>
            <td>don't block me</td>
            <td>don't block me</td>
        </tr>
    </tbody>
    <tbody data-bind="blockUI: isBlocked" style="background-color: lime">
        <tr>
            <td>block me</td>
            <td>block me</td>
            <td>block me</td>
        </tr>
        <tr>
            <td>block me</td>
            <td>block me</td>
            <td>block me</td>
        </tr>
        <tr>
            <td>block me</td>
            <td>block me</td>
      ...

CSS

div {
    border: 1px solid gray;
    padding: .5em;
}

JavaScript

ko.bindingHandlers.blockUI = {
    init: function (element, valueAccessor, allBindingsAccessor, viewModel) {

    },
    update: function (element, valueAccessor, allBindingsAccessor, viewModel) {
        var doBlock = ko.unwrap(valueAccessor());

        if (doBlock) {
            var options = allBindingsAccessor();
            var message = ko.unwrap(options.blockMessage) || "Blocked!";
            var useSmallMessage = options.useSmallMessage || false;
            var delay = options.delay || 0;

            opt = {
                message: "<span>" + message + "</span>",
                css: {
                    padding: 0,
                    margin: 0,
                    top: '1px',
                    left: '1px',
                    width: '80%',
                    textAlign: 'left',
                    color: '#000',
                    border: '2px solid #aaa',
                    backgroundColor: '#fff',
                    cursor: 'wait'
                },
                centerX: false,
                centerY: false
            };

            if (element.tagName == "TABLE" || element.tagName == "TBODY" || element.tagName == "TR") {
                this.timeout = setTimeout(function () {
                    $(element).find("td:first").block(opt);
                }, delay);
                this.timeout = setTimeout(function () {
                    $(element).find("td:not(:first)").block({
                        message: null
                    });
                }, delay);
            } else {
                this.timeout = setTimeout(function () {
                    $(element).block(opt);
                }, delay);
            }
        } else {
            if (element.tagName == "TABLE" || element.tagName == "TBODY" || element.tagName == "TR") {
                $(element).find("td:first").unblock();
                $(element).find("td:not(:first)").unblock();
            } else {
                $(element).unblock();
            }
       ...