#!/bin/sh

# Vars
## Define the hard drive to use
if [ -b '/dev/sda' ]; then
	hdd="/dev/sda"
else
	printf '%b\n' "Please check the hard drive to use"
	exit 0
fi
## Volume Group name to use for LVM
vgname="ovhsys"
## If the script should manage the partitions (delete, add,…)
manage_part=0
## Colors definition {{{
BLACK='\033[49;30m'
BLACKB='\033[49;90m'
RED='\033[0;31m'
REDB='\033[1;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
BLUE='\033[94;49m'
MAGENTA='\033[0;35m'
CYAN='\033[36;49m'
WHITE='\033[0;37m'
BOLD='\033[1m'
RESET='\033[0m'
## }}}

## Package to exclude from debootstrap install
dbs_pkg_exclude="vim"
## Package to include to debootstrap install
dbs_pkg_include="aptitude,bzip2,debconf-i18n,dialog,dmsetup,htop,isc-dhcp-client,isc-dhcp-common,locales,lvm2,openssh-server,pciutils,tmux,vim-nox,wget,zsh"

# Partitionning {{{
if [ "${manage_part}" -eq 0 ]; then
	## Remove all old partitions
	for part_number in 1 2 3 4 5 6 7 8; do
		[ -b "${hdd}""${part_number}" ] && parted "${hdd}" rm "${part_number}"
	done

	## Recreate partition (/boot and LV) {{{
	### Partition type
	parted "${hdd}" mklabel msdos
	### /boot
	parted "${hdd}" mkpart primary 0% 512MB
	parted "${hdd}" set 1 boot on
	### LV
	parted "${hdd}" mkpart primary 4194kB 100%
	parted "${hdd}" set 2 lvm on
	sudo pvcreate "${hdd}"2
	sudo vgcreate "${vgname}" "${hdd}"2
fi

mkfs.ext3 -F -L boot -- "${hdd}"1

## }}}
## Create Logical Volumes {{{
[ ! -b /dev/mapper/"${vgname}"-home ] && lvcreate -n home -L 20g  "${vgname}"
[ ! -b /dev/mapper/"${vgname}"-opt  ] && lvcreate -n opt  -L 2g   "${vgname}"
[ ! -b /dev/mapper/"${vgname}"-root ] && lvcreate -n root -L 5g   "${vgname}"
[ ! -b /dev/mapper/"${vgname}"-srv  ] && lvcreate -n srv  -L 2g   "${vgname}"
[ ! -b /dev/mapper/"${vgname}"-tmp  ] && lvcreate -n tmp  -L 10g  "${vgname}"
[ ! -b /dev/mapper/"${vgname}"-usr  ] && lvcreate -n usr  -L 15g  "${vgname}"
[ ! -b /dev/mapper/"${vgname}"-var  ] && lvcreate -n var  -L 10g  "${vgname}"
[ ! -b /dev/mapper/"${vgname}"-vz   ] && lvcreate -n vz   -L 150g "${vgname}"
[ ! -b /dev/mapper/"${vgname}"-bkp  ] && lvcreate -n bkp  -L 150g "${vgname}"
[ ! -b /dev/mapper/"${vgname}"-swap ] && lvcreate -n swap -L 2g   "${vgname}"

### Format the LV in ext4
cd -- /dev/"${vgname}" || exit 1
for lvname in *; do
	mkfs.ext4 -F -L "${lvname}" -- "${lvname}"
done
cd -- - || exit 1

### And format the swap
mkswap -L sw01 -- /dev/mapper/"${vgname}"-swap
## }}}
# }}}
# Debootstrap {{{
## Create and mount the system {{{
### Root
mkdir -p -- /target
mountpoint -q /target            || mount -- /dev/mapper/"${vgname}"-root /target

### boot - grub
mkdir -p -- /target/boot
mountpoint -q /target/boot       || mount -- ${hdd}1 /target/boot

### home LV
mkdir -p -- /target/home
mountpoint -q /target/home       || mount -- /dev/mapper/"${vgname}"-home /target/home
### opt LV
mkdir -p -- /target/opt
mountpoint -q /target/opt        || mount -- /dev/mapper/"${vgname}"-opt /target/opt
### srv LV
mkdir -p -- /target/srv
mountpoint -q /target/srv        || mount -- /dev/mapper/"${vgname}"-srv /target/srv
#### bkp LV
mkdir -p -- /target/srv/backup
mountpoint -q /target/srv/backup || mount -- /dev/mapper/"${vgname}"-bkp /target/srv/backup
### tmp LV
mkdir -p -- /target/tmp
mountpoint -q /target/tmp        || mount -- /dev/mapper/"${vgname}"-tmp /target/tmp
### usr LV
mkdir -p -- /target/usr
mountpoint -q /target/usr        || mount -- /dev/mapper/"${vgname}"-usr /target/usr
### var LV
mkdir -p -- /target/var
mountpoint -q /target/var        || mount -- /dev/mapper/"${vgname}"-var /target/var
#### vz LV
mkdir -p -- /target/var/lib/vz
mountpoint -q /target/var/lib/vz || mount -- /dev/mapper/"${vgname}"-vz /target/var/lib/vz

### Swap
swapon -- /dev/mapper/"${vgname}"-swap

### System
mkdir -p -- /target/dev/pts
mountpoint -q /target/dev/pts    || mount -o bind -- /dev/pts /target/dev/pts
mkdir -p -- /target/proc
mountpoint -q /target/proc       || mount -t proc -- proc /target/proc
mkdir -p -- /target/sys
mountpoint -q /target/sys        || mount -o bind -- /sys /target/sys
## }}}
## Run debootstrap
debootstrap --arch amd64 --include="${dbs_pkg_include}" --exclude="${dbs_pkg_exclude}" stretch /target http://ftp.fr.debian.org/debian

# }}}
# Configure system {{{
## Create the disk/partitions (eg. /dev/sda, /dev/sda1,…) on the target system {{{
### Create the disk
[ -b /target"${hdd}" ] || mknod --mode=660 /target"${hdd}" b 8 0

### Count the number of partitions on the rescue system
nb_part=$(ls -l -- "${hdd}"? | wc -l)
part=1
### Start at 1 and less/equal $nb_part
while [ "${part}" -le "${nb_part}" ]; do
	#### Create the partitions on the target system
	[ -b /target"${hdd}${part}" ] || mknod --mode=660 /target"${hdd}${part}" b 8 "${part}"
	(( part++ ))
done

### Fix group of disk/partitions
chgrp disk -- /target"${hdd}"*
## }}}
## Create LV inodes {{{
### Count the number of LV on the rescue system
nb_lv=$(ls -l -- /dev/dm-* | wc -l)
lv=0
### Start at 0 and less than $nb_lv cause it start at 0
while [ "${lv}" -lt "${nb_lv}" ]; do
	#### Create the LV on the target system
	[ -b /target/dev/dm-"${lv}" ] || mknod --mode=660 /target/dev/dm-"${lv}" b 252 "${lv}"
	(( lv++ ))
done

### Fix group of LV
chgrp disk -- /target/dev/dm-*
## }}}
## Create symlinks to LV {{{
### Get the list of all LV
tmp_list_lv="/tmp/lv.rescue.list"
find /dev/"${vgname}" -maxdepth 1 -type l -printf "%f\\n" > "${tmp_list_lv}"

### Create Volume Group and mapper directories
mkdir -p -- /target/dev/"${vgname}"
mkdir -p -- /target/dev/mapper

### For each LV
while IFS= read -r LV_NAME
do

	#### Create symlink in Volume Group directory on the target system (eg. /dev/mapper/ovhsys/home -> ../dm-0)
	[ -L /target/dev/"${vgname}/${LV_NAME}" ]        || ln -fs -- $(readlink /dev/"${vgname}/${LV_NAME}") /target/dev/"${vgname}/${LV_NAME}"

	#### Create symlink in mapper directory on the target system (eg. /dev/mapper/mapper/ovhsys-home -> ../dm-0)
	[ -L /target/dev/mapper/"${vgname}-${LV_NAME}" ] || ln -fs -- $(readlink /dev/"${vgname}/${LV_NAME}") /target/dev/mapper/"${vgname}-${LV_NAME}"
done < "${tmp_list_lv}"
rm -f -- "${tmp_list_lv}"

## }}}
## Fstab {{{
### Use the current mtab content as default fstab file for the target system
grep target /etc/mtab > /target/etc/fstab

### Ensure to enable swap
grep swap /target/etc/fstab || echo "/dev/mapper/${vgname}-swap    swap    swap     sw,pri=0      0   0" >> /target/etc/fstab

### Add extra tmpfs mount point
grep devtmpfs /target/etc/fstab    || echo "udev                  /dev       devtmpfs     rw,relatime,size=10240k,nr_inodes=2051120,mode=755 0 0" >> /target/etc/fstab
grep "/run " /target/etc/fstab     || echo "tmpfs                 /run        tmpfs       rw,size=15M,mode=755        0   0" >> /target/etc/fstab
grep "/run/lock" /target/etc/fstab || echo "tmpfs                 /run/lock   tmpfs       rw,size=5120k               0   0" >> /target/etc/fstab
grep "/run/shm" /target/etc/fstab  || echo "tmpfs                 /run/shm    tmpfs       rw,nodev,size=100M          0   0" >> /target/etc/fstab
grep "/var/tmp" /target/etc/fstab  || echo "/tmp                  /var/tmp    none        rw,bind,size=1M,mode=1777 0 0" >> /target/etc/fstab

### Remove all occurrences to /target
sed -i 's;/target;;g' /target/etc/fstab
## }}}
## Network {{{
net_device=$(ip r | grep "^default" | head -1 | cut -d" " -f5)
net_address=$(ip r | grep -vE "(^default|metric)" | grep "${net_device}.*src" | head -1 | awk -F" " '{print $NF}')
net_netmask=$(ipcalc "${net_address}" | awk '/Netmask:/{print $2;}')
net_broadcast=$(ip a s dev "${net_device}" | awk '/inet.*brd/{print $4}')
net_network=$(ip r | grep -vE "(^default|metric)" | grep "src ${net_address}" | head -1 | cut -d"/" -f1)
net_gateway=$(ip r | grep "^default" | head -1 | cut -d" " -f3)

printf '%b' "auto lo
iface lo inet loopback

auto ${net_device}
iface ${net_device} inet static
	address ${net_address}
	netmask ${net_netmask}
	network ${net_network}
	broadcast ${net_broadcast}
	gateway ${net_gateway}
	# FDN DNS - https://www.fdn.fr/actions/dns/
	dns-nameserver 80.67.169.12
	dns-nameserver 80.67.169.40

source-directory /etc/network/interfaces.d" > /target/etc/network/interfaces

## }}}
## Locale {{{
### Enable locale(s)
sed -i 's/^# \(en_US.UTF-8 UTF-8\)/\1/' /target/etc/locale.gen
#sed -i 's/^# \(fr_FR.UTF-8 UTF-8\)/\1/' /target/etc/locale.gen
chroot /target locale-gen

## }}}
## Timezone {{{
### Set timezone
printf '%b\n' "Europe/Paris" > /target/etc/timezone
ln -fs /usr/share/zoneinfo/Europe/Paris /target/etc/localtime
chroot /target dpkg-reconfigure --frontend noninteractive tzdata

## }}}
## Kernel and Grub {{{
chroot /target aptitude install --assume-yes --without-recommends -- linux-image-amd64 grub-pc
chroot /target grub-install "${hdd}"
chroot /target update-grub

## }}}
# }}}
# Finish {{{
## SSH {{{
### Allow root connections - this should be fixed if it works
sed -i 's/\(^\|^\#\)\(PermitRootLogin\).*/\2 yes/g' /target/etc/ssh/sshd_config
### Add current authorized_keys from the rescue system if present
if [ -f /root/.ssh/authorized_keys ]; then
	cp /root/.ssh/authorized_keys /target/root/.ssh/authorized_keys
else
	printf '%b\\n' "${REDB}You might want to define an authorized key for SSH/root in /target/etc/ssh/sshd_config${RESET}"
fi
## }}}
printf '%b\\n' "${REDB}Please change the root's password :${RESET}"
chroot /target passwd

printf '%b\\n' "${GREEN}The system is still available on /target but you can now try to reboot the hardware."

exit 0
# }}}