/**
 * Cookies.js, providing easy access to cookies thru the cookiejar object. Enabling so-called "subcookies" thru the subcookiejar 
 * object.
 * See this related blogpost for more information on how to use these objects:
 * 	<http://www.whatstyle.net/articles/28/subcookies>
 * 
 * @author Harmen Janssen <http://www.whatstyle.net>
 * @version 1.0
 * 
 */

/* based on http://www.quirksmode.org/js/cookies.html, by Peter-Paul Koch */
var cookiejar = {
	/* set a cookie */
	bake: function(cookieName,cookieValue,days,path){
		var expires='';
		if (days)
		{
			var date = new Date();
			date.setTime(date.getTime()+(days*24*60*60*1000));
			expires = "; expires="+date.toGMTString();
		}
		var thePath = '; path=/';
		if (path) thePath = '; path='+path;
		document.cookie = cookieName+'='+escape(cookieValue)+expires+thePath;
	},
	/* get a cookie value */
	fetch: function(cookieName){
		var nameEQ = cookieName + '=';
		var ca = document.cookie.split(';');
		for (var i=0; i<ca.length; i++)
		{
			var c = ca[i];
			while (c.charAt(0)==' ') c = c.substring(1,c.length);
			if (c.indexOf(nameEQ)==0) return unescape(c.substring(nameEQ.length,c.length));
		}
		return null;
	},
	/* delete a cookie */
	crumble: function(cookieName){
		cookiejar.bake(cookieName,'',-1);
	}
};

/* circumventing browser restrictions on the number of cookies one can use */
var subcookiejar = {
	nameValueSeparator: '$$:$$',
	subcookieSeparator: '$$/$$',
	/* set a cookie. subcookieObj is a collection of cookies to be. Every member of subcookieObj is the name of the cookie, its value
	 * the cookie value
	 */
	bake: function(cookieName,subcookieObj,days,path){
		var cookieValue = '';
		for (var i in subcookieObj)
		{
			cookieValue += i + subcookiejar.nameValueSeparator;
			cookieValue += subcookieObj[i];
			cookieValue += subcookiejar.subcookieSeparator;
		}
		/* remove trailing subcookieSeparator */
		cookieValue = cookieValue.substring(0,cookieValue.length-subcookiejar.subcookieSeparator.length);
		cookiejar.bake(cookieName,cookieValue,days,path);
	},
	/* get a subcookie */
	fetch: function(cookieName,subcookieName){
		var cookieValue = cookiejar.fetch(cookieName);
		var subcookies = cookieValue.split(subcookiejar.subcookieSeparator);
		for (var i=0; i<subcookies.length; i++)
		{
			var sc = subcookies[i].split(subcookiejar.nameValueSeparator);
			if (sc[0]==subcookieName) return sc[1];
		}
		return null;
	},
	/* delete a subcookie */
	crumble: function(cookieName,subcookieName,days,path)
	{
		var cookieValue = cookiejar.fetch(cookieName);
		var newCookieObj = {};
		var subcookies = cookieValue.split(subcookiejar.subcookieSeparator);
		for (var i=0; i<subcookies.length; i++)
		{
			var sc = subcookies[i].split(subcookiejar.nameValueSeparator);
			if (sc[0]!=subcookieName) newCookieObj[sc[0]] = sc[1];
		}
		subcookiejar.bake(cookieName,newCookieObj,days,path);
	}
};