gettorent for rutracker v0.1-alpha

#!/bin/bash

# Gettorrent Script by alxrt
# Version 0.1-alpha

# Синтаксис:
#   ./gettorrent TOPIC_ID [-h HOST] [-u USERNAME] [-p PASSWORD] [-o filepath]
#   TOPIC_ID: Идентификатор топика, к которому относится торент.
#   -h HOST: Хост трекера. Обычно rutracker.org или pornolab.net ;-)
#   -u USERNAME: Имя пользователя
#   -p PASSWORD: Пароль пользователя
#   -o filepath: Имя сохраняемого файла

# Настройки

TR_HOST="rutracker.org"
TR_USER=""
TR_PASSWORD=""

SC_COOKIE="/tmp/gt-$TR_HOST-$TR_USER.ck"
SC_UA="Mozilla/5.0 (X11; U; Linux x86_64; ru; rv:1.9.2.15) Gecko/20110303 Ubuntu/10.10 (maverick) Firefox/3.6.15"
SC_FILEPATH=""


#Functions

die() {
echo "Синтаксис:"
echo    "./gettorrent TOPIC_ID [-h HOST] [-u USERNAME] [-p PASSWORD] [-o filepath]"
echo    "TOPIC_ID: Идентификатор топика, к которому относится торент."
echo    "-h HOST: Хост трекера. Обычно rutracker.org или pornolab.net ;-)"
echo    "-u USERNAME: Имя пользователя"
echo    "-p PASSWORD: Пароль пользователя"
echo    "-o filepath: Имя сохраняемого файла"
}

waitf() {
    PERIOD="1."`head -n 1 /dev/urandom |md5sum |cut -d " " -f1|sed -e "s/[a-zA-Z\s].//g"`
    sleep 1.$period
}

check_auth() {
    if [ -w $SC_COOKIE ]; then
    cookie_data=`cat $SC_COOKIE`
    result=`curl -s -b $SC_COOKIE -c $SC_COOKIE -A "$SC_UA" "http://$TR_HOST/forum/index.php"|grep '<form method="post" action="http://login.rutracker.org/forum/login.php">'`
    if [ -z "$result" ]; then return `true`; else return `false`; fi
    else
    return `false`
    fi


}

make_auth(){
    if [ -w $SC_COOKIE ]; then
    cookie_data=`cat $SC_COOKIE`
    curl -s -b $SC_COOKIE -c $SC_COOKIE -A "$SC_UA" -d "login_username=$TR_USER" -d "login_password=$TR_PASSWORD" --data-binary "login=%C2%F5%EE%E4"  "http://login.$TR_HOST/forum/login.php">/dev/null
    else
    curl -s -c $SC_COOKIE -A "$SC_UA" -d "login_username=$TR_USER" -d "login_password=$TR_PASSWORD" --data-binary "login=%C2%F5%EE%E4"  "http://login.$TR_HOST/forum/login.php">/dev/null
    fi
}

get_torrent(){
    if [ -z "$SC_FILEPATH" ]; then
    curl -s -d "" -b $SC_COOKIE -c $SC_COOKIE -A "$SC_UA" -o "[$TR_HOST].t$SC_TOPICID.torrent"  -e "http://$TR_HOST/forum/viewtopic.php?t=$SC_TOPICID" "http://dl.$TR_HOST/forum/dl.php?t=$SC_TOPICID"
    else
    curl -s -d "" -b $SC_COOKIE -c $SC_COOKIE -A "$SC_UA" -o $SC_FILEPATH -e "http://$TR_HOST/forum/viewtopic.php?t=$SC_TOPICID" "http://dl.$TR_HOST/forum/dl.php?t=$SC_TOPICID"
    fi
}


SC_TOPICID=$1||die

while shift; do
    case $1 in
    -h)
        shift&&TR_HOST=$1||die
    ;;
    -u)
        shift&&TR_USER=$1||die
    ;;
    -p)
        shift&&TR_PASSWORD=$1||die
    ;;
    -o)
        shift&&SC_FILEPATH=$1||die
    ;;
    esac
done


if check_auth; then
    waitf
    get_torrent
else
    waitf
    make_auth
    waitf
    get_torrent
fi