#!/bin/sh

# Simple partitioning shell script.
# Copyright © 2013,2014 Guilhem Moulin <guilhem@fripost.org>
#
# 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 3 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, see <http://www.gnu.org/licenses/>.

# On most installations it should be enough to change what is marked as
# 'FIXME'.

set -ue

. /lib/fripost-partman/base.sh

# Configuration for a single disk
device=/dev/sda
raidLevel=

# Configuration for a RAID array
#device='/dev/sda /dev/sdb' #                                        FIXME
#raidLevel=raid1            # raid level                             FIXME
#raidNumActiveDevices=2     # number of active devices in the array  FIXME


n=0
for d in $device; do
    n=$(( $n + 1 ))
    wait_for_device $d

    # Umount existing mountpoints
    for mp in $(sed -nr "s#^$d\S*\s+(\S+).*#\1#p" /proc/mounts); do
        umount "$mp"
    done

    # Wipe the disk
    fripost_wipe $d

    # Create a disk label
    /sbin/parted -s $d mklabel gpt
    log "Created disklabel GPT for device $d"

    # Don't make an array of these partitions, but keep the alignment
    # regardless (at the expense of loosing some megabytes)

    # Create a EFI partition if needed; otherwise, create a partition needed
    # to put GRUB on GPT disklabels.
    if [ -d /proc/efi -o -d /sys/firmware/efi ]; then
        size=256M
        name=efi
        if [ $n -eq 1 ]; then
            anna-install dosfstools-udeb
            part_efi=$( fripost_mkpart $d $name $size +boot )
            fripost_mkfs vfat $part_efi -F 32
        else
            fripost_mkpart $d $name $size
        fi
    else
        size=8M
        name=bios_grub
        if [ $n -eq 1 ]; then
            fripost_mkpart $d $name $size +bios_grub
        else
            fripost_mkpart $d $name $size
        fi
    fi
done

db_get fripost/encrypt
encrypt=$RET


# Install GRUB on the first device in case of an array
db_set  grub-installer/bootdev "${device%% *}"
db_fset grub-installer/bootdev seen true

part_boot=
part_system=
# Create boot and system partitions
for d in $device; do
    pb=$( fripost_mkpart $d boot 64M )
    ps=$( fripost_mkpart $d system 100% )
    part_boot="${part_boot:+$part_boot }$pb"
    part_system="${part_system:+$part_system }$ps"
    /sbin/parted -s $d align-check opt ${ps#$d} \
        || fatal "$ps is not aligned"
done

# Create an array on top of that
if [ ${raidLevel:-} ]; then
    [ -d /dev/md ] || mkdir /dev/md

    devices="$part_boot"
    part_boot=/dev/md/boot
    fripost_mdadm_create "$part_boot" -f -R -l $raidLevel \
        ${raidNumActiveDevices:+-n $raidNumActiveDevices} $devices

    devices="$part_system"
    part_system=/dev/md/system
    fripost_mdadm_create "$part_system" -f -R -l $raidLevel \
        ${raidNumActiveDevices:+-n $raidNumActiveDevices} $devices

    # They were only meant to preserve alignment accross physical
    # devices.
    log "Remove dummy partitions"
    for d in ${device#* }; do
        # efi and bios_grub are only installed on the first disk
        fripost_rmpart $d efi       || true
        fripost_rmpart $d bios_grub || true
    done

    # Note that we're assembling the array *before* encryption rather
    # than the otherway around. dm_crypt being now multi-threaded, the
    # order shouldn't impact performances (and that order is
    # significantly simpler to configure).
fi



if [ $encrypt = true ]; then
    # Encrypt the system partition. We choose the key length and digest
    # depending on the architecture we're on; we use AES128 and SHA-256
    # on 32-bits platforms, and AES256 and SHA-512 on 64-bits platforms.
    arch=$(uname -m)
    if [ "$arch" = x86_64 ]; then
        keysize=256
        hash=sha512
    elif [ "$arch" = i386 -o "$arch" = i686 ]; then
        keysize=128
        hash=sha256
    fi
    # Note: XTS requires the key size to be doubled.
    fripost_encrypt $part_system system_crypt \
        --cipher aes-xts-plain64 --key-size $(( $keysize * 2 )) --hash $hash \
        --iter-time 5000 --use-random
    part_system=/dev/mapper/system_crypt
fi


# Ensure LVM2  is installed in the target chroot; create logical volumes
# for /, swap and /home.
apt-install lvm2 || true
vg=$(hostname)
pvcreate -ff -y $part_system
vgcreate $vg    $part_system

lvcreate -L 5G       -n root $vg    # FIXME
lvcreate -L 1G       -n swap $vg    # FIXME
lvcreate -l 100%FREE -n home $vg    # FIXME
vgchange -ay $vg


# Format the partitions
fripost_mkfs ext2 $part_boot    -E resize=512M -m1 -b 4096
fripost_mkfs ext4 /dev/$vg/root                    -b 4096
fripost_mkfs ext4 /dev/$vg/home                    -b 4096
mkswap            /dev/$vg/swap


# Stuff the fstab and mount the devices in the target
fripost_fstab $part_boot    /boot     ext2 noatime
[ -d /proc/efi -o -d /sys/firmware/efi ] && \
fripost_fstab $part_efi     /boot/efi vfat defaults
fripost_fstab /dev/$vg/root /         ext4 noatime,errors=remount-ro
fripost_fstab /dev/$vg/swap none      swap sw
fripost_fstab /dev/$vg/home /home     ext4 noatime
fripost_mount_partitions