#!/bin/bash
# setup dhcp server
# run this script as root

if [ "$#" -gt 1 ]; then
	echo "usage: $0 [file]" 1>&2
	exit 1
elif [ "$#" -eq 1 ]; then
	if ! [ -f "$1" ]; then
		echo "$1 is not a valid file" 1>&2
		exit 1
	fi
fi

if [ "$EUID" -ne 0 ]; then
	echo "Require root privilege" 1>&2
	exit 1
fi

yum install -y dhcp

if [ "$?" -ne 0 ]; then
	exit $?
elif [ "$#" -eq 1 ]; then
	cat "$1" > /etc/dhcp/dhcpd.conf
else
    # printf "Enter your network IP range [192.168.1.0/255.255.255.0]: "
    # read NET_IP
    # printf "Enter your available IP range [192.168.1.100-192.168.1.254]: "
    # read AVA_IP
cat <<- EOF >> /etc/dhcp/dhcpd.conf
#
# DHCP Server Configuration file.
#   see /usr/share/doc/dhcp*/dhcpd.conf.example
#   see dhcpd.conf(5) man page
#

subnet 192.168.122.0 255.255.255.0 {
}

subnet 10.0.0.0 netmask 255.255.255.0 {
range 10.0.0.200 10.0.0.254;
option domain-name "december.io";
option domain-name-servers ns.december.io;
option routers 10.0.0.1;
host ns {
    hardware ethernet 00:00:00:00:00:00;
    fixed-address 10.0.0.3;
}
}
EOF
fi

systemctl enable dhcpd
systemctl start dhcpd