#!/bin/sh

# automated script for easy installing zapret on debian or ubuntu based system
# system must use apt as package manager and systemd

[ $(id -u) -ne "0" ] && {
	echo root is required
	exec sudo $0
}

SCRIPT=$(readlink -f $0)
EXEDIR=$(dirname $SCRIPT)
LSB_INSTALL=/usr/lib/lsb/install_initd
LSB_REMOVE=/usr/lib/lsb/remove_initd
INIT_SCRIPT_SRC=$EXEDIR/init.d/debian/zapret
INIT_SCRIPT=/etc/init.d/zapret
GET_IPLIST=$EXEDIR/ipset/get_antizapret.sh
GET_IPLIST_PREFIX=$EXEDIR/ipset/get_

echo \* checking system ...

APTGET=$(which apt-get)
SYSTEMCTL=$(which systemctl)
[ ! -x "$APTGET" ] || [ ! -x "$SYSTEMCTL" ] && {
	echo not debian-like system
	exit 5
}


echo \* installing prerequisites ...

"$APTGET" update
"$APTGET" install -y --no-install-recommends ipset curl lsb-core dnsutils || {
	echo could not install prerequisites
	exit 6
}

[ ! -x "$LSB_INSTALL" ] || [ ! -x "$LSB_REMOVE" ] && {
	echo lsb install scripts not found
	exit 7
}


echo \* installing binaries ...

"$EXEDIR/install_bin.sh"


echo \* installing init script ...

"$SYSTEMCTL" stop zapret 2>/dev/null

script_mode=Y
[ -f "$INIT_SCRIPT" ] &&
{
	cmp -s $INIT_SCRIPT $INIT_SCRIPT_SRC ||
	{
		echo $INIT_SCRIPT already exists and differs from $INIT_SCRIPT_SRC
	   echo Y = overwrite with new version 
	   echo N = exit
	   echo L = leave current version and continue
		read script_mode
		case "${script_mode}" in
			Y|y|L|l)
				;;
			*)
				echo aborted
				;;
		esac
	}
}

if [ "$script_mode" = "Y" ] || [ "$script_mode" = "y" ]; then
	echo -n "copying : "
	cp -vf $INIT_SCRIPT_SRC $INIT_SCRIPT
fi


echo \* registering init script ...

"$LSB_REMOVE" $INIT_SCRIPT
"$LSB_INSTALL" $INIT_SCRIPT || {
	echo could not register $INIT_SCRIPT with LSB
	exit 20
}


echo \* downloading blocked ip list ...

"$GET_IPLIST" || {
	echo could not download ip list
	exit 25
}


echo \* adding crontab entry ...

CRONTMP=/tmp/cron.tmp
crontab -l >$CRONTMP
if grep -q "$GET_IPLIST_PREFIX" $CRONTMP; then
	echo some entries already exist in crontab. check if this is corrent :
	grep "$GET_IPLIST_PREFIX" $CRONTMP
else
	echo "0 12 * * */2 $GET_IPLIST" >>$CRONTMP
	crontab $CRONTMP
fi

rm -f $CRONTMP


echo \* starting zapret service ...

systemctl start zapret || {
	echo could not start zapret service
	exit 30
}

exit 0