#!/usr/bin/env bash

# call by install.sh

# install package
apt-get install -y hostapd dnsmasq

# disable *dhcpcd* *wlan0* interface
if [ -z "$(grep denyinterfaces /etc/dhcpcd.conf)" ] ; then
    echo 'denyinterfaces wlan0' >> /etc/dhcpcd.conf
fi

# edit network interface
mkdir -p /etc/network/interfaces.d
cp -f etc/network/interfaces.d/wlan0 /etc/network/interfaces.d/wlan0

# configure hostapd
if [ ! -f  /etc/hostapd/hostapd.conf ]; then
    cp -f etc/hostapd/hostapd.conf /etc/hostapd/hostapd.conf
fi
sed -i 's|^#\?DAEMON_CONF=.*|DAEMON_CONF="/etc/hostapd/hostapd.conf"|' /etc/default/hostapd

# configure dnsmasq
if [ -f /etc/dnsmasq.conf ]; then
    mv -f /etc/dnsmasq.conf /etc/dnsmasq.conf.orig
fi

cp -f etc/dnsmasq.conf /etc/dnsmasq.conf

# enable IPv4 forwarding
sed -i 's|^#\?net.ipv4.ip_forward=.*|net.ipv4.ip_forward=1|' /etc/sysctl.conf

# iptables
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
iptables -A FORWARD -i eth0 -o wlan0 -m state --state RELATED,ESTABLISHED -j ACCEPT
iptables -A FORWARD -i wlan0 -o eth0 -j ACCEPT
iptables-save > /etc/iptables.ipv4.nat

# iptables restore on boot
sed -i '/exit 0/i\
iptables-restore < /etc/iptables.ipv4.nat' /etc/rc.local

# enable service
systemctl unmask hostapd.service
systemctl enable hostapd.service
systemctl enable dnsmasq.service