Safely rename files inside directories with the same name as the parent directory name

rename.sh

#!/bin/bash
# Thu Oct 29 10:34:58 UTC 2020
# Lucian Maly, lmaly@redhat.com

for pathname in $(ls -d1 */);
do
        cd "${pathname}" || exit
        for file in *
        do
                mv -iv "${file}" "$(basename "${pathname}").${file##*.}"
        done
        cd ..
done

# Before:
# Active_Directory_Administration_Cookbook/9781789806984-ACTIVE_DIRECTORY_ADMINISTRATION_COOKBOOK.pdf
# Active_Directory_Administration_Cookbook/9781789806984_Code.zip
# Active_Directory_Administration_Cookbook/9781789806984.epub
# Active_Directory_Administration_Cookbook/9781789806984.mobi

# After:
# Active_Directory_Administration_Cookbook/Active_Directory_Administration_Cookbook.pdf
# Active_Directory_Administration_Cookbook/Active_Directory_Administration_Cookbook.zip
# Active_Directory_Administration_Cookbook/Active_Directory_Administration_Cookbook.epub
# Active_Directory_Administration_Cookbook/Active_Directory_Administration_Cookbook.mobi