The full score details are available as object dom. This way you can read and process any file like you need.
Some of the layout engines can render the song details on top of the music sheet.
Do you prefer an HTML5 canvas output instead of SVG? No problem.
Need display repeat marks? No problem, single repeats and multiple repeats come out of the box.
Even alternate repeat endings are no problem.
The guitar tuning of the current track is rendered on the top of the music notation.