ismdownloader2 Bash Smooth Streaming Wrapper

#!/bin/bash
# Author: Andrea Lazzarotto
# http://andrealazzarotto.com
# andrea.lazzarotto@gmail.com

# Smooth Streaming Bash Wrapper
# This is a wrapper for the ismdownloader2 Windows executable under Wine.

# License:
# Copyright 2012 Andrea Lazzarotto
# This script is licensed under the Gnu General Public License v3.0.
# You can obtain a copy of this license here: http://www.gnu.org/licenses/gpl.html

export WINEPREFIX=$HOME/.smoothwine

URL="$1"
NAME="$2"

if [ $# -ne 2 ]
then
  echo "Usage: `basename $0` url filename"
  exit 1
fi

function percentage {
    n=50
    p=$1

    echo -n '['
    while [ $n -gt 0 ]; do
        if [ $p -gt 0 ];
            then
                echo -n '#'
                p=$(( $p - 2 ))
            else echo -n '-'
        fi
        n=$(( $n - 1 ))
    done
    echo -n ']'
    echo -n " ${1}%"
}

dur="u"

echo "Verrà scaricato il video dall'url $URL"
echo ""
echo "Caricamento in corso..."
echo ""

wine $WINEPREFIX/drive_c/ismdownloader.exe "$URL" "C:\\$NAME.mkv" 2>/dev/null | while read -r -d '.' line; do
    line=`echo $line | tr '\r' ' '`

    if [ $dur = "u" ]; then # deve leggere la durata
        line=`echo $line | sed -s "s/.*Dur/Dur/g"`
        line1=`echo $line | cut -d ' ' -f 1`
        line2=`echo $line | cut -d ' ' -f 2`
        if [ $line1 = "Duration:" ]; then
            dur="$line2"
            h=`echo $dur | cut -d ':' -f 1`
            m=`echo $dur | cut -d ':' -f 2`
            s=`echo $dur | cut -d ':' -f 3`
            time=`echo "(($h * 60) + $m) * 60 + $s" | bc`

            echo -e "Durata del video: $dur\n"
        fi
    else # stampa la percentuale ogni volta che può
        line=`echo $line | cut -d ' ' -f 2`
        case $line in
            (*:*:*)
                par="$line"
                h=`echo $par | cut -d ':' -f 1`
                m=`echo $par | cut -d ':' -f 2`
                s=`echo $par | cut -d ':' -f 3`
                part=`echo "(($h * 60) + $m) * 60 + $s" | bc`
                perc=`echo "($part * 100) / $time" | bc`

                echo -e -n "\r"
                echo -n "$par "
                percentage $perc
                echo -n ' '
            ;;
        esac
    fi
done # ha finito di leggere l'output

echo -e "\n"
echo "Pulizia in corso..."
rm -rf "$WINEPREFIX/drive_c/$NAME"
mv "$WINEPREFIX/drive_c/$NAME.mkv" .
echo ""
echo "Download terminato, il video si trova in `pwd`/$NAME.mkv"