#!/bin/bash -lx
# Copyright (C) 2016 Ian Kelling

# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

# Setup arch pxe boot server from the base image.
# Requires manually downloading image to /a/opt, and set it's name below.

set -eE -o pipefail
trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR

x="$(readlink -f "$BASH_SOURCE")"
script_dir="${x%/*}"
cd /a/opt
iso="archlinux-2016.05.01-dual"
sfs=$iso/arch/x86_64/airootfs.sfs
rm -rf $iso
ex $iso.iso
sed -i --follow-symlinks -f - $iso/arch/boot/syslinux/archiso_pxe64.cfg <<EOF
1itotaltimeout 1
/^LABEL arch64_nfs/a menu default
s/^APPEND .*/\0 script=arch-iso-init/
EOF
# based on https://blog.chendry.org/2015/02/06/automating-arch-linux-installation.html
# and https://wiki.archlinux.org/index.php/Remastering_the_Install_ISO

s rm -rf squashfs-root # remove any existing folder
s unsquashfs $sfs
s mkdir -p squashfs-root/root/.ssh
s chmod 755 squashfs-root/root/.ssh
s cp ~/.ssh/id_rsa.pub squashfs-root/root/.ssh/authorized_keys

s cp $script_dir/arch-iso-init squashfs-root/root
s rm $sfs
s mksquashfs squashfs-root $sfs -comp xz
# file transfer to wrt is slow, so remove some useless files
rm $iso/arch/i686/airootfs.sfs $iso/arch/boot/i686/archiso.img
c $(dirname $sfs); md5sum ${sfs##*/} > airootfs.md5; b

# seems if you've done a pxe boot, mounted the nfs,
# then shutdown, it's still busy.
ssh wrt "/etc/init.d/nfsd stop; \
{ ! mount | grep /run/archiso/bootmnt || umount /run/archiso/bootmnt; } && \
rm -rf /mnt/usb/$iso"
scp -r $iso wrt:/mnt/usb
ssh wrt "cd /mnt/usb && rm -f tftpboot && ln -s $iso tftpboot"

# The default settings in the installer expect to find the NFS at /run/archiso/bootmnt

pxe-server default arch

# background:
# great documentation at https://wiki.archlinux.org/index.php/PXE
# background: arch can do netboot like ubuntu etc, but the docs look a little complicated, so fuck it,
# we use nfs cuz it's easy

rm -rf $iso
s rm -rf squashfs-root