Have you tried weasyprint? It turns .html into .pdf. Then I use a script with pdfinfo with the -dests option to get the page numbers of the chapters, mixes it with chapter titles from the .html file to create a ToC, which, in turn, gets included into the .html file again - just like TeX does it.
This is helpful in an environment where inputs are either HTML or EPUB files, and output is PDF for printing, HTML for the web site, and/or EPUB-formate.