/**
 * Read the JavaScript cookies tutorial at:
 *   http://www.netspade.com/articles/javascript/cookies.xml
 */

/**
 * Sets a Cookie with the given name and value.
 *
 * name       Name of the cookie
 * value      Value of the cookie
 * [expires]  Expiration date of the cookie (default: end of current session)
 * [path]     Path where the cookie is valid (default: path of calling document)
 * [domain]   Domain where the cookie is valid
 *              (default: domain of calling document)
 * [secure]   Boolean value indicating if the cookie transmission requires a
 *              secure transmission
 */
function setCookie(name, value, expires, path, domain, secure)
{
    document.cookie= name + "=" + escape(value) +
        ((expires) ? "; expires=" + expires.toGMTString() : "") +
        ((path) ? "; path=" + path : "") +
        ((domain) ? "; domain=" + domain : "") +
        ((secure) ? "; secure" : "");
}

function checkCookie(name) {
	var requiredfrom = "http://knowyourdrink.com/default.htm"; //  required prev. page
	//alert(getCookie("allowAccess"));
	//check for cookie
	if (getCookie(name) != "yes") {
		//if cookie doesn't exist, see if they came from the requiredfrom or if they just started
		if (document.referrer.indexOf(requiredfrom) == -1 || history.length == 0) {
			window.location=requiredfrom;
		} else {
			alert("You must enable your browser to accept cookies to fully access this site.");
		}
	}
}


/**
 * Gets the value of the specified cookie.
 *
 * name  Name of the desired cookie.
 *
 * Returns a string containing value of specified cookie,
 *   or null if cookie does not exist.
 */
function getCookie(name)
{
    var dc = document.cookie;
    var prefix = name + "=";
    var begin = dc.indexOf("; " + prefix);
    if (begin == -1)
    {
        begin = dc.indexOf(prefix);
        if (begin != 0) return null;
    }
    else
    {
        begin += 2;
    }
    var end = document.cookie.indexOf(";", begin);
    if (end == -1)
    {
        end = dc.length;
    }
    return unescape(dc.substring(begin + prefix.length, end));
}

/**
 * Deletes the specified cookie.
 *
 * name      name of the cookie
 * [path]    path of the cookie (must be same as path used to create cookie)
 * [domain]  domain of the cookie (must be same as domain used to create cookie)
 */
function deleteCookie(name, path, domain)
{
    if (getCookie(name))
    {
        document.cookie = name + "=" + 
            ((path) ? "; path=" + path : "") +
            ((domain) ? "; domain=" + domain : "") +
            "; expires=Thu, 01-Jan-70 00:00:01 GMT";
    }
}

/**
 * parses the URL for posted variables
 */
 
function parseQueryString (str) {
  str = str ? str : location.search;
  var query = str.charAt(0) == '?' ? str.substring(1) : str;
  var args = new Object();
  if (query) {
    var fields = query.split('&');
    for (var f = 0; f < fields.length; f++) {
      var field = fields[f].split('=');
      args[unescape(field[0].replace(/\+/g, ' '))] = unescape(field[1].replace(/\+/g, ' '));
    }
  }
  return args;
}
