#!/bin/bash

# T&M Hansson IT AB © - 2019, https://www.hanssonit.se/

# shellcheck disable=2034,2059
true
# shellcheck source=lib.sh
. <(curl -sL https://raw.githubusercontent.com/nextcloud/vm/master/lib.sh)

# Check if root
root_check

# Needs to be Ubuntu 18.04 and Multiverse
check_distro_version
check_multiverse

LABEL_=ncdata
MOUNT_=/mnt/$LABEL_

format() {
# umount if mounted
umount /mnt/* &> /dev/null

# mkdir if not existing
mkdir -p "$MOUNT_"

# Check what Hypervisor disks are available
SYSVENDOR=$(cat /sys/devices/virtual/dmi/id/sys_vendor)
if [ "$SYSVENDOR" == "VMware, Inc." ];
then
    SYSNAME="VMware"
    DEVTYPE=sdb
elif [ "$SYSVENDOR" == "Microsoft Corporation" ];
then
    SYSNAME="Hyper-V"
    DEVTYPE=sdb
elif [ "$SYSVENDOR" == "innotek GmbH" ];
then
    SYSNAME="VirtualBox"
    DEVTYPE=sdb
elif [ "$SYSVENDOR" == "Xen" ];
then
    SYSNAME="Xen/XCP-NG"
    DEVTYPE=xvdb
elif [ "$SYSVENDOR" == "QEMU" ];
then
    SYSNAME="KVM/QEMU"
    DEVTYPE=vdb
elif [ "$SYSVENDOR" == "DigitalOcean" ];
then
    SYSNAME="DigitalOcean"
    DEVTYPE=sda
elif partprobe /dev/sdb &>/dev/null;
then
    SYSNAME="machines"
    DEVTYPE=sdb
else
msg_box "It seems like you didn't mount a second disk. 
To be able to put the DATA on a second drive formatted as ZFS you need to add a second disk to this server.

This script will now exit. Please mount a second disk and start over."
exit 1
fi

# Get the name of the drive
DISKTYPE=$(fdisk -l | grep $DEVTYPE | awk '{print $2}' | cut -d ":" -f1 | head -1)
if [ "$DISKTYPE" != "/dev/$DEVTYPE" ]
then
msg_box "It seems like your $SYSNAME secondary volume (/dev/$DEVTYPE) does not exist.
This script requires that you mount a second drive to hold the data.

Please shutdown the server and mount a second drive, then start this script again.

If you want help you can buy support in our shop:
https://shop.hanssonit.se/product/premium-support-per-30-minutes/"
exit 1
fi

# Check if ZFS utils are installed
install_if_not zfsutils-linux 

# Check still not mounted
#These functions return exit codes: 0 = found, 1 = not found
isMounted() { findmnt -rno SOURCE,TARGET "$1" >/dev/null;} #path or device
isDevMounted() { findmnt -rno SOURCE        "$1" >/dev/null;} #device only
isPathMounted() { findmnt -rno        TARGET "$1" >/dev/null;} #path   only
isDevPartOfZFS() { zpool status | grep "$1" >/dev/null;} #device memeber of a zpool

if isPathMounted "/mnt/ncdata";      #Spaces in path names are ok.
then
msg_box "/mnt/ncdata is mounted and need to be unmounted before you can run this script."
    exit 1
fi

if isDevMounted "/dev/$DEVTYPE";
then
msg_box "/dev/$DEVTYPE is mounted and need to be unmounted before you can run this script."
    exit 1
fi

# Universal:
if isMounted "/mnt/ncdata";
then
msg_box "/mnt/ncdata is mounted and need to be unmounted before you can run this script."
    exit 1
fi

if isMounted "/dev/${DEVTYPE}1";
then
msg_box "/dev/${DEVTYPE}1 is mounted and need to be unmounted before you can run this script."
    exit 1
fi

if isDevPartOfZFS "$DEVTYPE";
then
msg_box "/dev/$DEVTYPE is a member of a ZFS pool and needs to be removed from any zpool before you can run this script."
    exit 1
fi

if lsblk -l -n | grep -v mmcblk | grep disk | awk '{ print $1 }' | tail -1 > /dev/null
then
msg_box "Formatting your $SYSNAME secondary volume ($DISKTYPE) when you hit OK.

*** WARNING: ALL YOUR DATA WILL BE ERASED! ***"
    if zpool list | grep "$LABEL_" > /dev/null
    then
        check_command zpool destroy "$LABEL_"
    fi
    check_command wipefs -a -f "$DISKTYPE"
    sleep 0.5
    check_command zpool create -f -o ashift=12 "$LABEL_" "$DISKTYPE"
    check_command zpool set failmode=continue "$LABEL_"
    check_command zfs set mountpoint="$MOUNT_" "$LABEL_"
    check_command zfs set compression=lz4 "$LABEL_"
    check_command zfs set sync=standard "$LABEL_"
    check_command zfs set xattr=sa "$LABEL_"
    check_command zfs set primarycache=all "$LABEL_"
    check_command zfs set atime=off "$LABEL_"
    check_command zfs set recordsize=128k "$LABEL_"
    check_command zfs set logbias=latency "$LABEL_"

else
msg_box "It seems like /dev/$DEVTYPE does not exist.
This script requires that you mount a second drive to hold the data.

Please shutdown the server and mount a second drive, then start this script again.

If you want help you can buy support in our shop:
https://shop.hanssonit.se/product/premium-support-per-30-minutes/"
exit 1
fi
}
format

# Do a backup of the ZFS mount
if is_this_installed libzfs2linux
then
    if grep -r $LABEL_ /etc/mtab
    then
        install_if_not zfs-auto-snapshot
        sed -i "s|date --utc|date|g" /usr/sbin/zfs-auto-snapshot
    fi
fi  

# Success!
if grep "$LABEL_" /etc/mtab
then
msg_box "$MOUNT_ mounted successfully as a ZFS volume.

Automatic scrubbing is done monthly via a cronjob that you can find here:
/etc/cron.d/zfsutils-linux

Automatic snapshots are taken with 'zfs-auto-snapshot'. You can list current snapshots with:
'sudo zfs list -t snapshot'. 
Manpage is here: 
http://manpages.ubuntu.com/manpages/bionic/man8/zfs-auto-snapshot.8.html

CURRENT STATUS:
$(zpool status $LABEL_)

$(zpool list)"
fi