remame_by_playlist_index

IFS=$'\n'
if [ $# -gt 0 ]; then
    if [ ! -f $1 ]; then
    echo "Error: file $1 does not exist"
    exit
    fi
    path=`echo $1 | rev | cut -d / -f 2- | rev`
    if [ $path == $1 ]; then
    path=$PWD
    fi
fi
if [ $# == 1 ]; then
    nb=0
    for i in `cat $1`
    do
    if [ -f $path/$i ]; then
        let ++nb
        if [ $nb -lt 10 ]; then
        digit="00"
        elif [ $nb -lt 100 ]; then
        digit="0"
        else
        digit=""
        fi
        mv -v $path/$i $path/$digit$nb" - "$i
    fi
    done
elif [ $# == 2 ] && [ $2 == "-r" ]; then
    for i in `ls $path`
    do
    name=`echo $i | cut -d - -f 2- | cut -c 2-`
    for j in `cat $1`
    do
        if [ $path/$name == $path/$j ]; then
        mv -v $path/$i $path/$name
        fi
    done
    done
else
    echo "Playlist files will be renamed by playlist index.
This script is designed for M3U playlists using relative paths.
Playlist file needs to be in playlist files folder, subfolders not supported.
You can use this script with other playlists if you convert them.
Index uses 3 digits: playlist files are renamed alphabetically up to 999 files.

Usage: $0 playlist [OPTION]
OPTION: -r: remove index from filename (add by default)"
fi