Torrentz.eu shell search API script

#!/bin/sh
#
# by Sairon Istyar, 2012
# distributed under the GPLv3 license
# http://www.opensource.org/licenses/gpl-3.0.html
#

# program to use for torrent download
program='/opt/usr/bin/transmission-remote'
progopts='-a'
# show N first matches by default
limit=15
# colors
numbcolor='\x1b[1;35m'
namecolor='\x1b[1;33m'
sizecolor='\x1b[1;36m'
seedcolor='\x1b[1;31m'
peercolor='\x1b[1;32m'
nonecolor='\x1b[0m'

printhelp() {
    echo -e "Usage:\n\t$0 [options] search query\n\nAvailable options:\n\t-h\t\tShow help\n\t-n [num]\tShow only first N results (default 15; max 50)\n\t-C\t\tDo not use colors"
}

while getopts :hCn: opt ; do
    case "$opt" in
        h) printhelp; exit 0;;
        n) limit="$OPTARG";;
        C) unset numbcolor; unset namecolor; unset sizecolor; unset seedcolor; unset peercolor; unset nonecolor;;
        *) echo -e "Unknown option(s)."; printhelp; exit 1;;
    esac
done

shift `expr $OPTIND - 1`

q=`echo "$*" | tr -d '\n' | od -t x1 -A n | tr ' ' '%'`

r=`curl -s "http://torrentz.eu/search?f=$q" \
    | grep -Eo '<dl><dt><a href=\"\/[[:alnum:]]*\">.*</a>|<span class=\"[speud]*\">[^<]*</span>' \
    | sed 's!<dl><dt><a href=\"/!!; \
        s!\">!|!; \
        s!<[/]*b>!!g; \
        N;N;N;s!\n<span class=\"[pesud]*\">!|!g; \
        s!</span>!!g; \
        s!</a>!!'`

n=`echo "$r" | wc -l`

IFS=$'\n'

echo "$r" \
    | head -n "$limit" \
    | awk -v N=1 \
        -v NU="$numbcolor" \
        -v NA="$namecolor" \
        -v SI="$sizecolor" \
        -v SE="$seedcolor" \
        -v PE="$peercolor" \
        -v NO="$nonecolor" \
        -F '|' \
        '{print NU N ") " NA $2 " " SI $3 " " SE $4 " " PE $5 NO; N++}'

read -p ">> Enter torrent No. to download: " down

down=`echo "$down" | sed 's/[^[:digit:]]*//g' | head -n 1`

if [ -z "$down" ] ; then
    echo "Not a number!"
    unset IFS
    exit 1
elif [ $down -ge 1 ] ; then
    if [ $down -le $limit ] ; then
        echo "Downloading..."
        $program $progopts "`echo "$r" | awk -F '|' 'NR=='$down'{print "magnet:?xt=urn:btih:" $1; exit}'`"
    else
        echo "Number too high! ($down)"
        unset IFS
        exit 3
    fi
else
    echo "Number too low! ($down)"
    unset IFS
    exit 2
fi

unset IFS