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