Knockout.js and autoNumeric.js bindings

knockout.autonumeric.js

ko.bindingHandlers.autoNumeric = function ($) {

    function getElementValue(el) {
        return parseFloat(el.autoNumericGet(), 10);
    }

    function getModelValue(accessor) {
        return parseFloat(ko.utils.unwrapObservable(accessor()), 10);
    }

    return {
        init: function (el, valueAccessor, bindingsAccessor, viewModel) {
            var $el = $(el),
                bindings = bindingsAccessor(),
                settings = bindings.settings,
                value = valueAccessor();

            function updateModelValue() {
                value(getElementValue($el));
            };

            if (settings.pSign === 's') {
                settings.aSign = ' ' + settings.aSign;
            } else {
                settings.aSign = settings.aSign + ' ';
            }

            $el.autoNumeric(settings);
            $el.autoNumericSet(getModelValue(value), settings);
            $el.change(updateModelValue);
        },
        update: function (el, valueAccessor, bindingsAccessor, viewModel) {
            var $el = $(el),
                newValue = getModelValue(valueAccessor()),
                elementValue = getElementValue($el),
                valueHasChanged = (newValue != elementValue);

            if ((newValue === 0) && (elementValue !== 0) && (elementValue !== "0")) {
                valueHasChanged = true;
            }

            if (valueHasChanged) {
                $el.autoNumericSet(newValue);
                setTimeout(function () { $el.change() }, 0);
            }
        }
    };
}