mp3reclaimer by Ri

#!/bin/bash

# mp3reclaimer
# retrieves mp3 files stored on ipods
# and renames them based on their id3 tags

# created 2015-06-26 Ri
# modified 2015-06-26 Ri

# set variables
myname=`basename $0`
ipodVolumePath=
ipodMusicPath="iPod_Control/Music"
outputDir=`pwd`

# declare functions
error() # error handler
{
    echo "$myname: $1" 1>&2
}

check_path() # checks if supplied argument is a valid path
{
    if [ ! -d "$1" ] && [ ! -f "$1" ]; then
        error "invalid path $1"
        exit 1
    fi
}

get_id3_tag() # gets id3 tags on supplied file
{
    id3v2 --list "$1" |
    grep -e "^$2" | awk 'BEGIN { FS=": " } ; { print $2 }'
}

# parse options and arguments
while [ $# -gt 0 ]; do
    case $1 in
        -o|--outputdir)
            outputDir="$2"
            shift 2
            ;;
        -*|--*)
            error "invalid option $1"
            exit 1
            ;;
        *)
            ipodVolumePath="$1"
            shift
            ;;

    esac
done

# perform sanity check
check_path "$ipodVolumePath"
check_path "$ipodVolumePath/$ipodMusicPath"
check_path "$outputDir"

# execute
for f in "$ipodVolumePath/$ipodMusicPath"/**/*.mp3; do

    artist=`get_id3_tag "$f" "TP1"`
    if [ "X$artist" = "X" ]; then
        artist="Unknown Artist"
    fi

    artist=`echo "$artist" | LANG=C sed 's/:/;/g'`
    artist=`echo "$artist" | LANG=C sed 's/\//:/g'`

    title=`get_id3_tag "$f" "TT2"`
    if [ "X$title" = "X" ]; then
        title="Unknown Title"
    fi

    title=`echo "$title" | LANG=C sed 's/:/;/g'`
    title=`echo "$title" | LANG=C sed 's/\//:/g'`

    newfilename="$artist - $title"
    cp -v "$f" "$outputDir/$newfilename.mp3"

done