#!/bin/sh 

# depends on following packages:
# apt-get install virtinst libvirt-bin dosfstools mtools kvm kvm-qemu
# apt-get install -t wheezy util-linux

# defaults, configurable in config
VG='vg01'
ETC='/etc/cloudinit'
CONFIG="$ETC/cloudinit.cfg"
VARDIR='/var/lib/libvirt/cloudinit'
SCRIPTDIR='/usr/local/bin/leap_cloudadmin'
KVM_URI='qemu:///system'
SEED='cloudinit_seed.img'

# overwrite defaults
[ -e $CONFIG ] && . $CONFIG

# unconfigurable variables
# swapsize is swapsize of the base image
SWAPSIZE=4
MIN_DISKSIZE=10
size=$MIN_DISKSIZE

fail() { [ $# -eq 0 ] || echo "$@"; exit 1; }
bad_usage() { usage 1>&2; [ $# -eq 0 ] || fail "$@"; exit 1; }

usage() {
       cat <<EOF

Usage: ${0##*/} -s ..  guest_name

  Creates a new guest VM using cloud-init to utilize nocloud.
  Uses $ETC/<guest_name>.cfg as meta- und user-data file  

  options:
    -h             show usage
    -s size        disk size in GB, including $SWAPSIZE GB swap. Defaults to minimal value of $MIN_DISKSIZE GB.

EOF
}


short_opts="hs:"
getopt_out=$(getopt --name "${0##*/}" \
       --options "${short_opts}" -- "$@") &&
       eval set -- "${getopt_out}" ||
       fail "Error !" 


while [ $# -ne 0 ]; do
       cur=${1}; next=${2};
       case "$cur" in
               -h) Usage ; exit 0;;
               -s) size=$next; shift;;
               --) shift; break;;
       esac
       shift;
done

[ $# -lt 1 ] && bad_usage "must provide guest name"
[ $# -gt 1 ] && bad_usage "too many arguments"

[ $size -lt $MIN_DISKSIZE ] && bad_usage "Minimal disk size is 10 GB !"


# requirements
echo "mtools_skip_check=1">~/.mtoolsrc
[ -e $VARDIR ] || ( mkdir $VARDIR ; chown libvirt-qemu $VARDIR )


vmname=$1
cfg="$ETC/$vmname.cfg"

[ -e /dev/$VG/$vmname ] && fail "/dev/$VG/$vmname exists - please delete it or choose another guest name"

[ -e $cfg ] ||  fail "please provide config file in $cfg"

echo
echo "Creating guest VM $vmname with size: $size GB, using $cfg for cloud-init"
echo "OK ? <Ctrl-C> to abort, <enter> to resume."
read enter

# is a VM with the same name defined ?
virsh dominfo $vmname > /dev/null 2>&1
if [ $? -eq 0 ]; then fail "Domain $vmname is defined in libvirt. Please undefine first."; fi


lvcreate -L ${size}g -n $vmname $VG
virt-clone --connect $KVM_URI -o leap-baseimage-wheezy -n $vmname -f /dev/$VG/$vmname  --force

# resize second (root) partition
echo ",+," | sfdisk -q  -N2  /dev/$VG/$vmname > /dev/null 2>&1


# create cloudinit seed disk

csplit -q --prefix "$VARDIR/$vmname" $cfg '/#cloud-config/'
metadata="$VARDIR/${vmname}00"
userdata="$VARDIR/${vmname}01"

$SCRIPTDIR/libvirt-make-seed-disk $VARDIR/$vmname-$SEED $userdata $metadata
$SCRIPTDIR/libvirt-write-disk-attach-xml $VARDIR/$vmname-$SEED > $VARDIR/$vmname-disk-attach.xml

echo
echo "Attached cloudinit-seeddisk is at $VARDIR/$vmname-$SEED"
echo
echo "Finished creating guest $vmname. Enjoy."
echo
echo "Press <return> to start the new guest."
read bogus

echo
echo 'Starting new guest, attaching to console. Exit with Ctrl+]'
echo

virsh start $vmname 
sleep 2 
virsh attach-device $vmname $VARDIR/$vmname-disk-attach.xml
virsh console $vmname 

#do we really need to detach the cloud-init disk ?
#virsh detach-device $vmname $VARDIR/$vmname-disk-attach.xml