remove-mp3-dupes.sh

#!/bin/bash
#
# Removes *.MP3 dupes of existing *.M4A files
#

##########################################################

# When you really want to delete files, set REAL=1
REAL=0

##########################################################

# Destination directory is optional (default: current)
destdir=$1
[ -z "$destdir" ] && destdir="."

# delimit by newline
IFS=$'\n'

if [ "$REAL" == "1" ]; then
    echo "*** Entering REAL mode. Will delete files!";
else
    echo "*** Entering FAKE mode. Will show which files to delete.";
fi

# Get all the M4As in the destination directory
m4as=$(find "$destdir" -name '*.m4a')

# Loop through all the M4As
for m4a in $m4as; do
    # Construct the MP3 equivalent filename
    mp3="$(echo $m4a | sed -e 's/\.m4a$/\.mp3/')";

    # Check if the MP3 file exists
    if [ -f "$mp3" ]; then
	# If it exists, remove it
        echo "> rm '$mp3'";

	# Only remove it if we are in REAL=1 mode
        if [ "$REAL" == "1" ]; then
            rm -v "$mp3";
	fi
    fi
done

usage.txt

$ find test -name '*.m*'
test/both m4a and mp3 1.m4a
test/both m4a and mp3 1.mp3
test/both m4a and mp3 2.m4a
test/both m4a and mp3 2.mp3
test/inner/directory/both m4a and mp3 1.m4a
test/inner/directory/both m4a and mp3 1.mp3
test/inner/directory/both m4a and mp3 2.m4a
test/inner/directory/both m4a and mp3 2.mp3
test/inner/directory/just m4a 1.m4a
test/inner/directory/just m4a 2.m4a
test/inner/directory/just mp3 1.mp3
test/inner/directory/just mp3 2.mp3
test/just m4a 1.m4a
test/just m4a 2.m4a
test/just mp3 1.mp3
test/just mp3 2.mp3

$ cd test

test $ bash ../remove-mp3-dupes.sh
*** Entering FAKE mode. Will show which files to delete.
> rm './both m4a and mp3 1.mp3'
> rm './both m4a and mp3 2.mp3'
> rm './inner/directory/both m4a and mp3 1.mp3'
> rm './inner/directory/both m4a and mp3 2.mp3'

test $ emacs ../remove-mp3-dupes.sh
# Edit REAL=1...

test $ bash ../remove-mp3-dupes.sh
*** Entering REAL mode. Will delete files!
> rm './both m4a and mp3 1.mp3'
./both m4a and mp3 1.mp3
> rm './both m4a and mp3 2.mp3'
./both m4a and mp3 2.mp3
> rm './inner/directory/both m4a and mp3 1.mp3'
./inner/directory/both m4a and mp3 1.mp3
> rm './inner/directory/both m4a and mp3 2.mp3'
./inner/directory/both m4a and mp3 2.mp3

test $ find . -name '*.m*'
./both m4a and mp3 1.m4a
./both m4a and mp3 2.m4a
./inner/directory/both m4a and mp3 1.m4a
./inner/directory/both m4a and mp3 2.m4a
./inner/directory/just m4a 1.m4a
./inner/directory/just m4a 2.m4a
./inner/directory/just mp3 1.mp3
./inner/directory/just mp3 2.mp3
./just m4a 1.m4a
./just m4a 2.m4a
./just mp3 1.mp3
./just mp3 2.mp3