configurePath=/etc/network/interfaces
interface="$1"
ip="$2"
mask="$3"
gateway="$4"
dns="$5"

testPermission(){
	if [ $(id -u) -ne 0 ]; then
		echo "You need root access\n"
		exit 1
	fi
}

clearFile(){
	if [ -f "$configurePath" ]; then
		sudo rm "$configurePath"
	fi
}

stringInterface(){
	local stringInterface="auto $interface\n"
	stringInterface+="iface $interface inet static\n"
	stringInterface+="	address $ip\n"
	stringInterface+="	netmask $mask\n"
	stringInterface+="	gateway $gateway\n"
	stringInterface+="	dns-nameservers $dns\n"

	echo "$stringInterface"
}

createInterface(){
	sudo echo -e "$(stringInterface)" | sudo tee "$configurePath"
}

testInterface(){
	sudo /etc/init.d/networking restart
}

testPermission
createInterface
testInterface