//

//  Cookie Functions -- "Night of the Living Cookie" Version (25-Jul-96)

//

//  Written by:  Bill Dortch, hIdaho Design <bdortch@hidaho.com>

//  The following functions are released to the public domain.

//

//  This version takes a more aggressive approach to deleting

//  cookies.  Previous versions set the expiration date to one

//  millisecond prior to the current time; however, this method

//  did not work in Netscape 2.02 (though it does in earlier and

//  later versions), resulting in "zombie" cookies that would not

//  die.  DeleteCookie now sets the expiration date to the earliest

//  usable date (one second into 1970), and sets the cookie's value

//  to null for good measure.

//

//  Also, this version adds optional path and domain parameters to

//  the DeleteCookie function.  If you specify a path and/or domain

//  when creating (setting) a cookie**, you must specify the same

//  path/domain when deleting it, or deletion will not occur.

//

//  The FixCookieDate function must now be called explicitly to

//  correct for the 2.x Mac date bug.  This function should be

//  called *once* after a Date object is created and before it

//  is passed (as an expiration date) to SetCookie.  Because the

//  Mac date bug affects all dates, not just those passed to

//  SetCookie, you might want to make it a habit to call

//  FixCookieDate any time you create a new Date object:

//

//    var theDate = new Date();

//    FixCookieDate (theDate);

//

//  Calling FixCookieDate has no effect on platforms other than

//  the Mac, so there is no need to determine the user's platform

//  prior to calling it.

//

//  This version also incorporates several minor coding improvements.

//

//  **Note that it is possible to set multiple cookies with the same

//  name but different (nested) paths.  For example:

//

//    SetCookie ("color","red",null,"/outer");

//    SetCookie ("color","blue",null,"/outer/inner");

//

//  However, GetCookie cannot distinguish between these and will return

//  the first cookie that matches a given name.  It is therefore

//  recommended that you *not* use the same name for cookies with

//  different paths.  (Bear in mind that there is *always* a path

//  associated with a cookie; if you don't explicitly specify one,

//  the path of the setting document is used.)

//  

//  Revision History:

//

//    "Toss Your Cookies" Version (22-Mar-96)

//      - Added FixCookieDate() function to correct for Mac date bug

//

//    "Second Helping" Version (21-Jan-96)

//      - Added path, domain and secure parameters to SetCookie

//      - Replaced home-rolled encode/decode functions with Netscape's

//        new (then) escape and unescape functions

//

//    "Free Cookies" Version (December 95)

//

//

//  For information on the significance of cookie parameters, and

//  and on cookies in general, please refer to the official cookie

//  spec, at:

//

//      http://www.netscape.com/newsref/std/cookie_spec.html    

//

//******************************************************************

//

// "Internal" function to return the decoded value of a cookie

//

function getCookieVal (offset) {

  var endstr = document.cookie.indexOf (";", offset);

  if (endstr == -1)

    endstr = document.cookie.length;

  return unescape(document.cookie.substring(offset, endstr));

}

//

//  Function to correct for 2.x Mac date bug.  Call this function to

//  fix a date object prior to passing it to SetCookie.

//  IMPORTANT:  This function should only be called *once* for

//  any given date object!  See example at the end of this document.

//

function FixCookieDate (date) {

  var base = new Date(0);

  var skew = base.getTime(); // dawn of (Unix) time - should be 0

  if (skew > 0)  // Except on the Mac - ahead of its time

    date.setTime (date.getTime() - skew);

}

//

//  Function to return the value of the cookie specified by "name".

//    name - String object containing the cookie name.

//    returns - String object containing the cookie value, or null if

//      the cookie does not exist.

//

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;

}

//

//  Function to create or update a cookie.

//    name - String object containing the cookie name.

//    value - String object containing the cookie value.  May contain

//      any valid string characters.

//    [expires] - Date object containing the expiration data of the cookie.  If

//      omitted or null, expires the cookie at the end of the current session.

//    [path] - String object indicating the path for which the cookie is valid.

//      If omitted or null, uses the path of the calling document.

//    [domain] - String object indicating the domain for which the cookie is

//      valid.  If omitted or null, uses the domain of the calling document.

//    [secure] - Boolean (true/false) value indicating whether cookie transmission

//      requires a secure channel (HTTPS).  

//

//  The first two parameters are required.  The others, if supplied, must

//  be passed in the order listed above.  To omit an unused optional field,

//  use null as a place holder.  For example, to call SetCookie using name,

//  value and path, you would code:

//

//      SetCookie ("myCookieName", "myCookieValue", null, "/");

//

//  Note that trailing omitted parameters do not require a placeholder.

//

//  To set a secure cookie for path "/myPath", that expires after the

//  current session, you might code:

//

//      SetCookie (myCookieVar, cookieValueVar, null, "/myPath", null, true);

//

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 to delete a cookie. (Sets expiration date to start of epoch)

//    name -   String object containing the cookie name

//    path -   String object containing the path of the cookie to delete.  This MUST

//             be the same as the path used to create the cookie, or null/omitted if

//             no path was specified when creating the cookie.

//    domain - String object containing the domain of the cookie to delete.  This MUST

//             be the same as the domain used to create the cookie, or null/omitted if

//             no domain was specified when creating the 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";

  }

}



//

//  Examples

//

// var expdate = new Date ();

// FixCookieDate (expdate); // Correct for Mac date bug - call only once for given Date object!

// expdate.setTime (expdate.getTime() + (24 * 60 * 60 * 1000)); // 24 hrs from now 

// SetCookie ("ccpath", "http://www.hidaho.com/colorcenter/", expdate);

// SetCookie ("ccname", "hIdaho Design ColorCenter", expdate);

// SetCookie ("tempvar", "This is a temporary cookie.");

// SetCookie ("ubiquitous", "This cookie will work anywhere in this domain",null,"/");

// SetCookie ("paranoid", "This cookie requires secure communications",expdate,"/",null,true);

// SetCookie ("goner", "This cookie must die!");

// document.write (document.cookie + "<br>");

// DeleteCookie ("goner");

// document.write (document.cookie + "<br>");

// document.write ("ccpath = " + GetCookie("ccpath") + "<br>");

/// document.write ("ccname = " + GetCookie("ccname") + "<br>");

/// document.write ("tempvar = " + GetCookie("tempvar") + "<br>");

// end script -->