CommonJS cookie handler

cookie.js

module.exports = {
    
    getItem: function (sKey) {
        if (!sKey) {
            return null;
        }
        return decodeURIComponent(document.cookie.replace(new RegExp("(?:(?:^|.*;)\\s*" + encodeURIComponent(sKey).replace(/[\-\.\+\*]/g, "\\$&") + "\\s*\\=\\s*([^;]*).*$)|^.*$"), "$1")) || null;
    },

    setItem: function (sKey, sValue, vEnd, sPath, sDomain, bSecure) {
        if (!sKey || /^(?:expires|max\-age|path|domain|secure)$/i.test(sKey)) {
            return false;
        }
        var sExpires = "";
        if (vEnd) {
            switch (vEnd.constructor) {
                case Number:
                    sExpires = vEnd === Infinity ? "; expires=Fri, 31 Dec 9999 23:59:59 GMT" : "; max-age=" + vEnd;
                    break;
                case String:
                    sExpires = "; expires=" + vEnd;
                    break;
                case Date:
                    sExpires = "; expires=" + vEnd.toUTCString();
                    break;
            }
        }
        document.cookie = encodeURIComponent(sKey) + "=" + encodeURIComponent(sValue) + sExpires + (sDomain ? "; domain=" + sDomain : "") + (sPath ? "; path=" + sPath : "") + (bSecure ? "; secure" : "");
        return true;
    },

    removeItem: function (sKey, sPath, sDomain) {
        if (!this.hasItem(sKey)) {
            return false;
        }
        document.cookie = encodeURIComponent(sKey) + "=; expires=Thu, 01 Jan 1970 00:00:00 GMT" + (sDomain ? "; domain=" + sDomain : "") + (sPath ? "; path=" + sPath : "");
        return true;
    },

    hasItem: function (sKey) {
        if (!sKey) { return false; }
        return (new RegExp("(?:^|;\\s*)" + encodeURIComponent(sKey).replace(/[\-\.\+\*]/g, "\\$&") + "\\s*\\=")).test(document.cookie);
    },
    
    keys: function () {
        var aKeys = document.cookie.replace(/((?:^|\s*;)[^\=]+)(?=;|$)|^\s*|\s*(?:\=[^;]*)?(?:\1|$)/g, "").split(/\s*(?:\=[^;]*)?;\s*/);
        for (var nLen = aKeys.length, nIdx = 0; nIdx < nLen; nIdx++) {
            aKeys[nIdx] = decodeURIComponent(aKeys[nIdx]);
        }
        return aKeys;
    }

}