/* http://www.webreference.com/js/column8/functions.html */

/*
	 name - name of the cookie
	 value - value of the cookie
	 [expires] - expiration date of the cookie
		 (defaults to end of current session)
	 [path] - path for which the cookie is valid
		 (defaults to path of calling document)
	 [domain] - domain for which the cookie is valid
		 (defaults to domain of calling document)
	 [secure] - Boolean value indicating if the cookie transmission requires
		 a secure transmission
	 * an argument defaults when it is assigned null as a placeholder
	 * a null placeholder is not required for trailing omitted arguments
*/
function setCookie(name, value, expires, path, domain, secure) {
	var curCookie = name + "=" + escape(value) +
			((expires) ? "; expires=" + expires.toGMTString() : "") +
			((path) ? "; path=" + path : "") +
			((domain) ? "; domain=" + domain : "") +
			((secure) ? "; secure" : "");
	document.cookie = curCookie;
}


/*
	name - name of the desired cookie
	return 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));
}


/*
	 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)
	 path and domain default if assigned null or omitted if no explicit
		 argument proceeds
*/
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";
	}
}