// helper functions
        
    function pfc_getParameterByName(name, url = window.location.href) {
        name = name.replace(/[\[\]]/g, '\\$&');
        var regex = new RegExp('[?&]' + name + '(=([^&#]*)|&|#|$)'),
            results = regex.exec(url);
        if (!results) return null;
        if (!results[2]) return '';
        return decodeURIComponent(results[2].replace(/\+/g, ' '));
    }
    function pfc_setCookie(cname, cvalue, exdays) {
      const d = new Date();
      d.setTime(d.getTime() + (exdays*24*60*60*1000));
      expires = "expires="+ d.toUTCString();
      document.cookie = cname + "=" + cvalue + ";" + expires + ";path=/";
    }

    function pfc_getCookie(cname) {
      let name = cname + "=";
      let ca = document.cookie.split(';');
      for(let i = 0; i < ca.length; i++) {
        let c = ca[i];
        while (c.charAt(0) == ' ') {
          c = c.substring(1);
        }
        if (c.indexOf(name) == 0) {
          return c.substring(name.length, c.length);
        }
      }
      return "";
    }

    // main process
    function pfc_main()
    {
    var oldPFCE=pfc_getCookie("PFCE");  // get an existing cookie


    // see if 3rd party values have been passed in by a profundcom link
    var PFCE=pfc_getParameterByName("PFCE");
    var PFCT=pfc_getParameterByName("PFCT");
    var PFCN=pfc_getParameterByName("PFCN");

    if(PFCE)
    {
        // data is in the query string - clean it
       var cleanhref=window.location.href;
       cleanhref=cleanhref.replace("&PFCE="+PFCE,"");
       cleanhref=cleanhref.replace("&PFCT="+PFCT,"");
       cleanhref=cleanhref.replace("&PFCN="+PFCN,"");
       if(cleanhref.endsWith("?"))
         cleanhref=cleanhref.substring(0,cleanhref.length-1); 
       history.pushState({}, document.title, cleanhref)
    }
        if(!oldPFCE)      //have we already set a 1st pary cookie, if not see if 3rd pery will work
    {
        var new_script = document.createElement('script');                                                    
        new_script.setAttribute('src','https://thirdave.profundcom.net/dms/w.php?PFCC=true');
        document.head.appendChild(new_script);
        return;
    }
    
    if(PFCE)
    {           //values from link in query params
       pfc_setCookie("PFCE",PFCE, 30);
       pfc_setCookie("PFCT",PFCT, 30);
       pfc_setCookie("PFCN",PFCN, 30);
    }
    else
    {
        //values from 1st party cookies
        PFCE=oldPFCE;
        PFCT=pfc_getCookie("PFCT");
        PFCN=pfc_getCookie("PFCN");
    }
    if(!PFCE)
    {
    // set dummy as it would be in 3rd party
        PFCE=dummyPFCE;
        pfc_setCookie("PFCE",PFCE, 30);
        PFCT=dummyPFCT;
        pfc_setCookie("PFCT",PFCT, 30);
    }

    // call the tracked with the data we have from query string or 1st party cookie
    var new_script = document.createElement('script');                                                    
    new_script.setAttribute('src','https://thirdave.profundcom.net/dms/w.php?PFCE='+PFCE+'&PFCT='+PFCT+'&PFCN='+PFCN+'&oldPFCE='+oldPFCE);
    document.head.appendChild(new_script);
    }
    pfc_main();