/**
 * 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>
 * Check out this other blogpost for information about the new version:
 *  <http://www.whatstyle.net/articles/46/subcookies_v2>
 * 
 * @author Harmen Janssen <http://www.whatstyle.net>
 * @version 2.0
 * 
 */

/* based on http://www.quirksmode.org/js/cookies.html, by Peter-Paul Koch */
var cookiejar = {
  /* set a cookie */
  bake: function(cookieName,cookieValue,days,path,domain) {
    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;
    }
    var theDomain = "";
    if (domain) {
      theDomain = '; domain=' + domain;
    }
    document.cookie = cookieName+'='+encodeURIComponent(cookieValue)+expires+thePath+theDomain;
    return true;
  },
  /* 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 decodeURIComponent(c.substring(nameEQ.length, c.length));
      }
    }
    return null;
  },
  /* delete a cookie */
  crumble: function(cookieName) {
    return 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,domain) {
    var existingCookie;
    /* check for existing cookie */
    if (existingCookie = subcookiejar.fetch (cookieName)) {
      /* if a cookie by the same name is found, 
       * append its values to the subcookieObj.
       */
      for (var i in existingCookie) {
        if (!(i in subcookieObj)) {
          subcookieObj[i] = existingCookie[i];
        }
      }
    }
    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);
    return cookiejar.bake(cookieName,cookieValue,days,path,domain);
  },
  /* get a subcookie */
  fetch: function(cookieName,subcookieName) {
    var cookieValue = cookiejar.fetch(cookieName);
    /* proceed only if a cookie was found */
    if (!cookieValue) {
      return null;
    }
    var subcookies = cookieValue.split(subcookiejar.subcookieSeparator);
    var cookieObj = {};
    for (var i=0,sclen=subcookies.length; i<sclen; i++) {
      var sc = subcookies[i].split(subcookiejar.nameValueSeparator);
      cookieObj [sc[0]] = sc[1];
    }
    /* if subcookieName is given, return that subcookie if available, or null.
     * else, return the entire cookie as an object literal
     */
    if (subcookieName != undefined) {
      if (subcookieName in cookieObj) {
        return cookieObj[subcookieName];
      }
      return null;
    }
    return cookieObj;
  },
  /* delete a subcookie */
  crumble: function(cookieName,subcookieName,days,path) {
    var cookieValue = cookiejar.fetch(cookieName);
    if (!cookieValue) {
      return false;
    }
    var newCookieObj = {};
    var subcookies = cookieValue.split(subcookiejar.subcookieSeparator);
    for (var i=0, sclen=subcookies.length; i<sclen; i++)  {
      var sc = subcookies[i].split(subcookiejar.nameValueSeparator);
      if (sc[0] != subcookieName) {
        newCookieObj[sc[0]] = sc[1];
      }
    }
    return subcookiejar.bake(cookieName,newCookieObj,days,path);
  }
};