#!/usr/bin/env bash

# import_vm - Imports a VM to a PVC cluster from local files
# Part of the Parallel Virtual Cluster (PVC) system
#
#    Copyright (C) 2018-2020 Joshua M. Boniface <joshua@boniface.me>
#
#    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 <https://www.gnu.org/licenses/>.
#
###############################################################################

set -o errexit
set -o pipefail

usage() {
    echo -e "Import a VM to a PVC cluster from local files."
    echo -e "Usage:"
    echo -e "  $0 <destination_cluster> <destination_pool> <vm_configuration_file> <vm_disk_file_1> [<vm_disk_file_2>] [...]"
    echo -e ""
    echo -e "Important information:"
    echo -e " * At least one disk must be specified; all disks that are present in vm_configuration_file"
    echo -e "   should be specified, though this is not strictly requireda."
    echo -e " * Do not switch the cluster primary coordinator while the script is running."
    echo -e " * Ensure you have enough space on the destination cluster to store all VM disks."
}

fail() {
    echo -e "$@"
    exit 1
}

# Arguments
if [[ -z ${1} || -z ${2} || -z ${3} || -z ${4} ]]; then
    usage
    exit 1
fi
destination_cluster="${1}"; shift
destination_pool="${1}"; shift
vm_config_file="${1}"; shift
vm_disk_files=( ${@} )

# Verify the cluster is reachable
pvc -c ${destination_cluster} status &>/dev/null || fail "Specified destination_cluster is not accessible"

# Determine the connection IP
cluster_address="$( pvc cluster list 2>/dev/null | grep -i "^${destination_cluster}" | awk '{ print $2 }' )"

echo "Verification complete."

# Determine information about the VM from the config file
parse_xml_field() {
    field="${1}"
    line="$( grep -F "<${field}>" ${vm_config_file} )"
    awk -F '>|<' '{ print $3 }' <<<"${line}"
}
vm_name="$( parse_xml_field name )"
echo "Importing VM ${vm_name}..."
pvc -c ${destination_cluster} vm define ${vm_config_file} 2>/dev/null

# Create the disks on the cluster
for disk_file in ${vm_disk_files[@]}; do
    disk_file_basename="$( basename ${disk_file} )"
    disk_file_ext="${disk_file_basename##*.}"
    disk_file_name="$( basename ${disk_file_basename} .${disk_file_ext} )"
    disk_file_size="$( stat --format="%s" ${disk_file} )"

    echo "Importing disk ${disk_file_name}... "
    pvc -c ${destination_cluster} storage volume add ${destination_pool} ${disk_file_name} ${disk_file_size}B 2>/dev/null
    pvc -c ${destination_cluster} storage volume upload ${destination_pool} ${disk_file_name} ${disk_file} 2>/dev/null
done