#!/bin/bash

ISCSI_TARGET_IQN="iqn.2000-01.com.synology:SynologyNAS.Target-13.b63ef49539c"
ISCSI_TARGET_IP="192.168.1.5"

PI_SERIAL="$(vcgencmd otp_dump | grep 28: | sed s/.*://g)"
ISCSI_INITIATOR_IQN="$(tail -1 /etc/iscsi/initiatorname.iscsi | grep InitiatorName | cut -d '=' -f 2 | tr -d '"')"
ISCSI_DEVICE="/dev/sda"
ISCSI_ROOT_PARTITION="/dev/sda1"
TFTP_ROOT="/volume1/rpi/tftpboot/"
PI_HOSTNAME=$(hostname)
PI_IP=$(ifconfig eth0 | awk '/inet /{ print $2;}')
PI_MAC=$(ifconfig eth0 | awk '/ether/{ print $2;}' | tr ':' '-')
PI_NETMASK=$(ifconfig eth0 | awk '/netmask/{ print $4;}')
#ISCSI_INITIATOR_IQN=$(cat /etc/iscsi/iscsi.initramfs | grep 'ISCSI_INITIATOR=' | cut -d '=' -f 2)
#ISCSI_TARGET_IP=$(cat /etc/iscsi/iscsi.initramfs | grep 'ISCSI_TARGET_IP=' | cut -d '=' -f 2)
#ISCSI_TARGET_IQN=$(cat /etc/iscsi/iscsi.initramfs | grep 'ISCSI_TARGET=' | cut -d '=' -f 2)
NFS_DIR="/nfs/$(hostname -s)-boot"
NFS_IP=${ISCSI_TARGET_IP}
NFS_ROOT_PATH="${TFTP_ROOT}${PI_SERIAL}"
ISCSI_ROOT_DIR="/iscsi/$(hostname -s)-iscsi"
#ISCSI_ROOT_UUID=$(sudo blkid | grep ${ISCSI_ROOT_PARTITION} | tr ' ' '\n' | grep -w UUID | cut -d '=' -f 2 | tr -d '"')
#ISCSI_ROOT_PARTUUID=$(sudo blkid | grep ${ISCSI_ROOT_PARTITION} | tr ' ' '\n' | grep PARTUUID | cut -d '=' -f 2 | tr -d '"')

#Make sure ISCSI Initiator IQN is set
sudo iscsiadm \
  --mode discovery \
  --type sendtargets \
  --portal ${ISCSI_TARGET_IP}

#Install Required Software
apt -y install net-tools nfs-common open-iscsi

#Install libraspberrypi-lib if not installed
LIBRASPBERRYPI_BIN_INSTALLED=$(apt-cache policy libraspberrypi-bin | grep 'Installed' | cut -d ':' -f 2)
LIBRASPBERRYPI_BIN_IS_INSTALLED=" (none)"

if [ "${LIBRASPBERRYPI_BIN_INSTALLED}" = "${LIBRASPBERRYPI_BIN_IS_INSTALLED}" ]
then
   apt -y install libraspberrypi-bin
   echo "ISCSI_INITIATOR_IQN=${ISCSI_INITIATOR_IQN}"
   echo ""
   echo ""
   echo "Please re-run the script after rebooting"
   echo ""
   read -p "Press any key to reboot ..."
   reboot now
else
   echo ""
   echo ""
   echo ""
   echo ""
   echo "Make sure the ISCSI and NFS targets are set op on the server"
   echo ""
   echo "ISCSI_INITIATOR_IQN=${ISCSI_INITIATOR_IQN}"
   read -p "PI_SERIAL=${PI_SERIAL}"
fi

# Copy over to the TFTP server, via the NFS mount.
mkdir -p /nfs/$(hostname -s)-boot
mount ${NFS_IP}:${NFS_ROOT_PATH} /nfs/$(hostname -s)-boot
rsync --info=progress2 -a --delete /boot/ /nfs/$(hostname -s)-boot

update-initramfs -v -k "$(uname -r)" -c -b /nfs/$(hostname -s)-boot

# Update the cmdline.txt file that the pi boots with
# https://www.raspberrypi.org/documentation/configuration/cmdline-txt.md
# ip= docs can be found at
# https://git.kernel.org/pub/scm/libs/klibc/klibc.git/tree/usr/kinit/ipconfig/README.ipconfig
# However, don't put anything after static in the line below, because it completely breaks
# everything in a very non-obvious way.

touch /nfs/$(hostname -s)-boot/cmdline.txt
cp config.txt /nfs/$(hostname -s)-boot/config.txt

sed -i -r -e \
  "s/$/ net.ifnames=0 dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 rootfstype=btrfs elevator=deadline rootwait fixrtc ip=dhcp root=UUID=${ISCSI_ROOT_UUID}$ISCSI_INITIATOR=${ISCSI_INITIATOR_IQ>
  /nfs/$(hostname -s)-boot/cmdline.txt

#Mount ISCSI
#sudo iscsiadm \
sudo iscsiadm \
  --mode node \
  --targetname ${ISCSI_TARGET_IQN} \
  --portal ${ISCSI_TARGET_IP} \
  --login

#read -p "Pausing after iscsiadm"
# Sleep otherwise it errors
sleep 5

# Partition the ISCSI Device
sudo parted ${ISCSI_DEVICE} mklabel gpt
sleep 5
sudo parted --align optimal ${ISCSI_DEVICE} mkpart primary btrfs 0% 100%
sleep 5

# Create the btrfs Filesystem
yes | sudo mkfs.btrfs -f /${ISCSI_ROOT_PARTITION}
sleep 5
sudo mkdir -p ${ISCSI_ROOT_DIR}
sudo mount "${ISCSI_ROOT_PARTITION}" ${ISCSI_ROOT_DIR}

# Copy the root filesystem
sudo rsync -xa --info=progress2 --exclude /nfs --exclude /iscsi / ${ISCSI_ROOT_DIR}


# Update /boot to point to the NFS mount of the TFTP folder for the Pi.
sudo sed -i -r -E \
  "s@.*/boot +.*@${NFS_IP}:${NFS_ROOT_PATH} /boot nfs defaults,proto=tcp 0 0@" \
  ${ISCSI_ROOT_DIR}/etc/fstab

# Update / to point to the iSCSI drive.
sudo sed -i -r -E \
  "s@.*/ +.*@PARTUUID=${ISCSI_ROOT_PARTUUID} / btrfs _netdev,noatime 0 1@" \
  ${ISCSI_ROOT_DIR}/etc/fstab

# Create links in /boot
ln /nfs/$(hostname -s)-boot/firmware/bcm2711-rpi-4-b.dtb /nfs/$(hostname -s)-boot/bcm2711-rpi-4-b.dtb
ln /nfs/$(hostname -s)-boot/firmware/start4.elf /nfs/$(hostname -s)-boot/start4.elf
ln /nfs/$(hostname -s)-boot/firmware/fixup4.dat /nfs/$(hostname -s)-boot/fixup4.dat

ISCSI_ROOT_UUID=$(sudo blkid | grep ${ISCSI_ROOT_PARTITION} | tr ' ' '\n' | grep -w UUID | cut -d '=' -f 2 | tr -d '"')
ISCSI_ROOT_PARTUUID=$(sudo blkid | grep ${ISCSI_ROOT_PARTITION} | tr ' ' '\n' | grep PARTUUID | cut -d '=' -f 2 | tr -d '"')
echo "ISCSI UUID=${ISCSI_ROOT_UUID}"
echo "ISCSI PARTUUID=${ISCSI_ROOT_PARTUUID}"
echo "ISCSI TARGET IQN=${ISCSI_TARGET_IQN}"
echo "ISCSI INITIATOR IQN=${ISCSI_INITIATOR_IQN}"
read -p "Installation Is Complete. Please remove the SD card and reboot."

# The connection to the iSCSI device is no longer needed, so clean it up.
sudo umount ${ISCSI_ROOT_DIR}
sudo iscsiadm --m node -T ${ISCSI_TARGET_IQN} --portal ${ISCSI_TARGET_IP}:3260 -u
sudo iscsiadm -m node -o delete -T ${ISCSI_TARGET_IQN} --portal ${ISCSI_TARGET_IP}:3260
sudo rm -rf ${ISCSI_ROOT_DIR}

# The connection to the NFS device is no longer needed, so clean it up
sudo umount ${NFS_DIR}
rm -rf ${NFS_DIR}

# Shutdown
sudo shutdown now