I have a folder on my desktop named Models. In the folder, there are named folders with jpeg files without the .jpg extensions. The jpeg file names are random hashes. I would like to use a bash script to batch rename these jpeg files to their directory names with increments and append the .jpg extension on each file.

It's basically something like

Models/

      Alice/
          a5ccB2ff3e
          ee420bc4a
          2acee54dc
          ...
     Alex/
          de33fa24c0
          d1eaa48e0a
          ...

And I want to to be like

Models/

     Alice/
          Alice001.jpg
          Alice002.jpg
          Alice003.jpg
          ...

     Alex/
          Alex001.jpg
          Alex002.jpg
          ...