audacious save curent song

#!/bin/bash

function set_win_on_top() {
    pid=$1
    sleep 0.2
    win_id=`wmctrl -l -p | grep ${pid} | awk '{print $1}'`
    wmctrl -i -r ${win_id} -b add,above 2>/dev/null
}


function remove_numeral_prefix() {
    words=$1
    for i in $(seq 1 ${#words})
    do
        if [[ ${words:i-1:1} =~ [0-9] ]];then
            continue
        else
            echo ${words:i-1:${#words}}
            break
        fi
    done
}


function audacious_copy_song() {
    curent_song_loc=$(audtool current-song-filename)
    file_name="${curent_song_loc##*/}"
    file_extension="${file_name##*.}"
    file="${file_name%.*}"
    file=$(remove_numeral_prefix "$file")
    file=$(echo "$file" | sed -e 's/[][~!{}()$@<>:;,.`%+="\x27/\|?*&-]//g' -e 's/[[:space:]]\+/ /g')
    dest_song_loc=$(echo ~/Music/$file"."$file_extension)
    if [ -f "$dest_song_loc" ]; then
        unique_file_name=$file"_"$(date +%s%N)"."$file_extension
        unique_dest_song_loc=$(echo ~/Music/$unique_file_name)
        cp "$(echo $curent_song_loc)" "$(echo $unique_dest_song_loc)"
        zenity --notification --text "file copied:\r\n$unique_file_name"
    else
        cp "$(echo $curent_song_loc)" "$(echo ~/Music/$file"."$file_extension)"
        zenity --notification --text "file copied:\r\n$file"."$file_extension"
    fi
}

audacious_copy_song & set_win_on_top $!