#! /bin/bash

# modified from upstream fai example
error=0; trap 'error=$(($?>$error?$?:$error))' ERR # save maximum error code

netplan_yaml() {
    # network configuration using ubuntu's netplan.io
    local IFNAME="$1"
    local METHOD="$2"
    echo     "Generating netplan configuration for $IFNAME ($METHOD)" >&2
    echo     "# generated by FAI"
    echo     "network:"
    echo     "  version: 2"
    echo     "  renderer: $RENDERER"
    case "$RENDERER" in
      networkd)
        echo     "  ethernets:"
        echo     "    $IFNAME:"
        case "$METHOD" in
          dhcp)
            echo "      dhcp4: true"
            ;;
          static)
            echo "      addresses: [$CIDR]"
            echo "      gateway4: $GATEWAYS_1"
            echo "      nameservers:"
            echo "        search: [$DOMAIN]"
            echo "        addresses: [${DNSSRVS// /, }]"
            ;;
        esac
    esac
}

iface_stanza() {
    # classic network configuration using /etc/network/interfaces
    local IFNAME="$1"
    local METHOD="$2"
    echo "Generating interface configuration for $IFNAME ($METHOD)" >&2
    echo "# generated by FAI"
    echo "auto $IFNAME"
    echo "iface $IFNAME inet $METHOD"
    case "$METHOD" in
      static)
        echo "    address $IPADDR"
        echo "    netmask $NETMASK"
        echo "    broadcast $BROADCAST"
        echo "    gateway $GATEWAYS"
        ;;
    esac
}

newnicnames() {

    # determine predictable network names only for stretch and above

    [ $do_init_tasks -eq 0 ] && return
    [ -z "$NIC1" ] && return
    ver=$($ROOTCMD dpkg-query --showformat='${Version}' --show udev)
    if dpkg --compare-versions $ver lt 220-7; then
	return
    fi


    fields="ID_NET_NAME_FROM_DATABASE ID_NET_NAME_ONBOARD ID_NET_NAME_SLOT ID_NET_NAME_PATH"
    for field in $fields; do
	name=$(udevadm info /sys/class/net/$NIC1 | sed -rn "s/^E: $field=(.+)/\1/p")
	if [[ $name ]]; then
	    NIC1=$name
	    break
	fi
    done
    # This condition is only needed because the nfsroot I use
    # is based on Jessie, which has an old udev which can't
    # figure out the persistent interface name used in stretch.
    if ifclass VM; then NIC1=ens3; return; fi
    if [[ ! $name ]]; then
	echo "$0: error: could not find systemd predictable network name. Using $NIC1."
    fi
}

if [ -z "$NIC1" ]; then
    echo "WARNING: \$NIC1 is not defined. Cannot add ethernet to /etc/network/interfaces."
fi
CIDR=$(ip -o -f inet addr show $NIC1 | awk '{print $4}')
newnicnames

case "$FAI_ACTION" in
  install|dirinstall)
    ifclass DHCPC && METHOD=dhcp || METHOD=static
    ifclass XORG && RENDERER=NetworkManager || RENDERER=networkd

    if [ -d $target/etc/netplan ]; then
        # Ubuntu >= 17.10 with netplan.io
        if [ -n "$NIC1" ]; then
            netplan_yaml $NIC1 $METHOD > $target/etc/netplan/01-${NIC1}.yaml
        fi
    elif [ -d $target/etc/network/interfaces.d ]; then
        # ifupdown >= 0.7.41 (Debian >= 8, Ubuntu >= 14.04)

      if ifclass VM; then
        # note, this condition would apply to the elif below too,
        # but I don't specify a static ip in fai, so not bothering
        cat > $target/etc/network/interfaces <<-EOF
	# generated by FAI
	auto lo $NIC1
	iface lo inet loopback
	iface $NIC1 inet dhcp
EOF
      else
        cat > $target/etc/network/interfaces <<-EOF
        # generated by FAI
        auto lo br0
        iface lo inet loopback
        iface $NIC1 inet manual
        # make a bridge by default so we can have bridged vms.
        # Some example I read had stp on, but i don't need stp,
        # and it causes a vm to fail pxe boot, presumably unless
        # you add some delay.
        # http://wiki.libvirt.org/page/PXE_boot_%28or_dhcp%29_on_guest_failed
        iface br0 inet dhcp
          bridge_ports $NIC1
          bridge_stp off
          bridge_maxwait 0
EOF
      fi
    else
      (
        iface_stanza lo loopback
        iface_stanza $NIC1 $METHOD
      ) > $target/etc/network/interfaces
    fi

    if ! ifclass DHCPC ; then
        [ -n "$NETWORK" ] && echo "localnet $NETWORK" > $target/etc/networks
        if [ ! -L $target/etc/resolv.conf -a -e /etc/resolv.conf ]; then
            cp -p /etc/resolv.conf $target/etc
        fi
    fi
    ;;
esac

# here fcopy is mostly used, when installing a client for running in a
# different subnet than during the installation
fcopy -iM /etc/resolv.conf
fcopy -iM /etc/network/interfaces /etc/networks

exit $error