How to do page numbering in header/footer htmls with wkhtmltopdf?

I'm developing an electronic invoicing system, and one of our features is generating PDFs of the invoices, and mailing them. We have multiple templates for invoices, and will create more later, so we decided to use HTML templates, generate HTML document, and then convert it to PDF. But we're facing a problem with wkhtmltopdf, that as far as I know (I've been Googleing for days to find the solution) we cannot simply both use HTML as header/footer, and show page numbers in them.

In a bug report (or such) ( http://code.google.com/p/wkhtmltopdf/issues/detail?id=140 ) I read that with JavaScript it is achievable this combo. But no other information on how to do it can be found on this page, or elsewhere.

It is, of course not so important to force using JavaScript, if with wkhtmltopdf some CSS magic could work, it would be just as awesome, as any other hackish solutions.

Thanks!

To show the page number and total pages you can use this javascript snippet in your footer or header code:

  var pdfInfo = {};
  var x = document.location.search.substring(1).split('&');
  for (var i in x) { var z = x[i].split('=',2); pdfInfo[z[0]] = unescape(z[1]); }
  function getPdfInfo() {
    var page = pdfInfo.page || 1;
    var pageCount = pdfInfo.topage || 1;
    document.getElementById('pdfkit_page_current').textContent = page;
    document.getElementById('pdfkit_page_count').textContent = pageCount;
  }

And call getPdfInfo with page onload

Of course pdfkit_page_current and pdfkit_page_count will be the two elements that show the numbers.

Snippet taken from here