Automatically add tracknumber to audio files

Dear all,

I use gPodder to download podcasts and airsonic to organize them.

In general that works very well. Unfortunately, gPodder is only able to use existing metadata and rename downloaded audiofiles to: publishing date - name of the podcast.

Of course airsonic can add a tracknumber, however that needs to be done manually and somehow you can't order the list by filename first.

Is there a easy and automatic way to add a tracknumber to the podcast files?

Manually I would order them by filename and then start enumarting from one.

Thanks in advance!