Jookie: a jQuery JSON cookie handler (See http://joncom.be/code/jquery-jookie/)

gistfile1.js

/*
  License:
  Jookie 1.0 jQuery Plugin

  Copyright (c) 2009 Jon Combe (http://joncom.be)

  Permission is hereby granted, free of charge, to any person
  obtaining a copy of this software and associated documentation
  files (the "Software"), to deal in the Software without
  restriction, including without limitation the rights to use,
  copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the
  Software is furnished to do so, subject to the following
  conditions:

  The above copyright notice and this permission notice shall be
  included in all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  OTHER DEALINGS IN THE SOFTWARE.
*/

(function($) {

    $.Jookie = {
        Data:         {},
        Debug:        function(a)     { Debug(a)        },
        Delete:       function(a)     { Delete(a)       },    // delete cookie
        Get:          function(a,b)   { return Get(a,b) },    // get a single value from a cookie
        Initialise:   function(a,b)   { Initialise(a,b) },
        Set:          function(a,b,c) { Set(a,b,c)      },    // set a single value to a cookie
        Unset:        function(a,b)   { Unset(a,b)      }     // remove a single value from a cookie
    };

    // PUBLIC: show debugging information
    function Debug(sName) {
        var lsRegExp = /\+/g;
        var sJSON = unescape(String(Extract(sName)).replace(lsRegExp, " "));
        alert("Name: " + sName +
              "\nLifespan: " + $.Jookie.Data[sName].iLifespan +
              " minutes\nCookie Existed Prior to Init: " + $.Jookie.Data[sName].bMadeEarlier + "\n\n" +
              sJSON);
    }

    // PUBLIC: delete a cookie
    function Delete(sName) {
        delete $.Jookie.Data[sName];
        document.cookie = (sName + "=; expires=" + (new Date(1990, 6, 3)).toGMTString() + "; path=/");
    }

    // PRIVATE: extract the contents of a cookie
    function Extract(sName) {
        var vValue = null;
        var aContents = document.cookie.split(';');
        sName += "=";

        // loop through cookie strings
        for (var iIndex in aContents) {
            var sString = aContents[iIndex];
            while (sString.charAt(0) == " ") {
                sString = sString.substring(1, sString.length);
            }
            if (sString.indexOf(sName) == 0) {
                vValue = sString.substring(sName.length, sString.length);
                break;
            }
        }

        // return extracted value
        return vValue;
    }

    // PUBLIC: retrieve a cookie's value
    function Get(sName, sVariableName) {
        return $.Jookie.Data[sName].oValues[sVariableName];
    }

    // PUBLIC: Initialise the plugin
    function Initialise(sName, iLifespanInMinutes) {
        if (typeof $.Jookie.Data[sName] == "undefined") {
            var oRetrievedValues = {};
            var bCookieExists = false;

            // extract cookie value
            var vCookieValue = Extract(sName);
            if (vCookieValue !== null) {
                oRetrievedValues = JSON.parse( unescape(String(vCookieValue).replace(/\+/g, " ")) );
                bCookieExists = true;
            }

            // add cookie details to object
            $.Jookie.Data[sName] = { iLifespan    : iLifespanInMinutes,
                                     bMadeEarlier : bCookieExists,
                                     oValues      : oRetrievedValues };
            Save(sName);
        }
    }

    // PRIVATE: write cookie to user's browser
    function Save(sName) {
        var sExpires = "";
        if ($.Jookie.Data[sName].iLifespan > 0) {
            var dtDate = new Date();
            dtDate.setMinutes(dtDate.getMinutes() + $.Jookie.Data[sName].iLifespan);
            sExpires = ("; expires=" + dtDate.toGMTString());
        }
        document.cookie = (sName + "=" +
                           escape(JSON.stringify($.Jookie.Data[sName].oValues)) +
                           sExpires + "; path=/");
    }

    // PUBLIC: set and save a cookie's value
    function Set(sName, sVariableName, vValue) {
        $.Jookie.Data[sName].oValues[sVariableName] = vValue;
        Save(sName);
    }

    // PUBLIC: delete a single variable from a cookie
    function Unset(sName, sVariableName) {
        delete $.Jookie.Data[sName].oValues[sVariableName];
        Save(sName);
    }

})(jQuery);