// AFFILIATE TRACKING CODE ====================================================

/* cookies.js */
/*
     Example File From "JavaScript and DHTML Cookbook"
     Published by O'Reilly & Associates
     Copyright 2003 Danny Goodman
*/

// utility function to retrieve a future expiration date in proper format;
// pass three integer parameters for the number of days, hours,
// and minutes from now you want the cookie to expire; all three
// parameters required, so use zeros where appropriate
function getExpDate(days, hours, minutes) {
  var expDate = new Date();
  if (typeof days == "number" && typeof hours == "number" && typeof hours == "number") {
    expDate.setDate(expDate.getDate() + parseInt(days));
    expDate.setHours(expDate.getHours() + parseInt(hours));
    expDate.setMinutes(expDate.getMinutes() + parseInt(minutes));
    return expDate.toGMTString();
  }
}

// utility function called by getCookie()
function getCookieVal(offset) {
  var endstr = document.cookie.indexOf (";", offset);
  if (endstr == -1) { endstr = document.cookie.length; }
  return unescape(document.cookie.substring(offset, endstr));
}

// primary function to retrieve cookie by name
function getCookie(name) {
  var arg = name + "=";
  var alen = arg.length;
  var clen = document.cookie.length;
  var i = 0;
  while (i < clen) {
    var j = i + alen;
    if (document.cookie.substring(i, j) == arg) {
      return getCookieVal(j);
    }
    i = document.cookie.indexOf(" ", i) + 1;
    if (i == 0) break; 
  }
  return null;
}

// store cookie value with optional details as needed
function setCookie(name, value, expires, path, domain, secure) {
  document.cookie = name + "=" + escape (value) +
    ((expires) ? "; expires=" + expires : "") +
    ((path) ? "; path=" + path : "") +
    ((domain) ? "; domain=" + domain : "") +
    ((secure) ? "; secure" : "");
}

// remove the cookie by setting ancient expiration date
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";
  }
}

// Tracks referrer via cookie so we can have nice stats.
// Only set referrer cookie if we don't have one.
function writeReferrerCookie() {
  if(getCookie("referrer") == null && getCookie("entry_page") == null) {
    setCookie("referrer", document.referrer, getExpDate(90,0,0));
    setCookie("entry_page", window.location, getExpDate(90,0,0));
  }
}
// Tracks affiliate code
function writeAffiliateCookie() {
  if(getCookie("affiliate") == null) {
    var query_params = document.location.href.toQueryParams();
    if(query_params['affiliate'] != null) {
      setCookie("affiliate", query_params['affiliate'], getExpDate(90,0,0));
    }
  }
}

function writeAppCookies() {
  writeAffiliateCookie();
  writeReferrerCookie();
}

Event.observe(window, "load", writeAppCookies);