I have a file that has the name a_b-c-d-e-f.txt. I would like to take that current name and swap the dashes and underscores so that it becomes a-b_c_d_e_f.txt.

My intuition tells me to try rename or tr, but I'm having issues with this. Here is my current attempt

#!/bin/bash

for i in *.txt; do

  [ -f "$i" ] || break

  newFile=$(echo "$i" | tr '-' '_')

  cp "$i" $newFile

done

With this, I end up with

a_b_c_d_e_f.txt

It's that part between a-b that should not be changing. Also, that dash is not necessarily always in that place in the filename. For example, it may look like

a-b-c_d-e-f.txt

Or any combination like this. I want them to flip not matter their place in the name.