#!/bin/bash

# -------------------------------------------------------------------------- #
# Copyright 2002-2017, OpenNebula Project, OpenNebula Systems                #
#                                                                            #
# Licensed under the Apache License, Version 2.0 (the "License"); you may    #
# not use this file except in compliance with the License. You may obtain    #
# a copy of the License at                                                   #
#                                                                            #
# http://www.apache.org/licenses/LICENSE-2.0                                 #
#                                                                            #
# Unless required by applicable law or agreed to in writing, software        #
# distributed under the License is distributed on an "AS IS" BASIS,          #
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   #
# See the License for the specific language governing permissions and        #
# limitations under the License.                                             #
#--------------------------------------------------------------------------- #

# clone fe:SOURCE host:remote_system_ds/disk.i size
#   - fe is the front-end hostname
#   - SOURCE is the path of the disk image in the form DS_BASE_PATH/disk
#   - host is the target host to deploy the VM
#   - remote_system_ds is the path for the system datastore in the host

SRC=$1
DST=$2
VM_ID=$3
DS_ID=$4

if [ -z "${ONE_LOCATION}" ]; then
    TMCOMMON=/var/lib/one/remotes/tm/tm_common.sh
else
    TMCOMMON=$ONE_LOCATION/var/remotes/tm/tm_common.sh
fi

DRIVER_PATH=$(dirname $0)

source $TMCOMMON
source ${DRIVER_PATH}/../../datastore/libfs.sh

#-------------------------------------------------------------------------------
# Set dst path and dir
#-------------------------------------------------------------------------------

DST_PATH=`arg_path $DST`
DST_HOST=`arg_host $DST`
DST_DIR=`dirname $DST_PATH`
DS_DIR=`dirname $DST_DIR`

SRC_ARG_PATH=`arg_path $SRC`

DS_SYS_ID=$(echo $DST_DIR | $AWK -F '/' '{print $(NF-1)}')

#-------------------------------------------------------------------------------
# Get Image information
#-------------------------------------------------------------------------------

DISK_ID=$(basename ${DST_PATH} | cut -d. -f2)

XPATH="${DRIVER_PATH}/../../datastore/xpath.rb --stdin"

unset i j XPATH_ELEMENTS

while IFS= read -r -d '' element; do
    XPATH_ELEMENTS[i++]="$element"
done < <(onevm show -x $VM_ID| $XPATH \
                    /VM/TEMPLATE/DISK[DISK_ID=$DISK_ID]/SIZE \
                    /VM/TEMPLATE/DISK[DISK_ID=$DISK_ID]/ORIGINAL_SIZE \
                    /VM/TEMPLATE/DISK[DISK_ID=$DISK_ID]/DRIVER \
                    /VM/TEMPLATE/DISK[DISK_ID=$DISK_ID]/DATASTORE_ID \
                    /VM/TEMPLATE/DISK[DISK_ID=$DISK_ID]/IMAGE_ID \
                    /VM/TEMPLATE/DISK[DISK_ID=$DISK_ID]/TYPE \
                    /VM/HISTORY_RECORDS/HISTORY[last\(\)]/TM_MAD)

#rbt: add DRIVER var
SIZE="${XPATH_ELEMENTS[j++]}"
ORIGINAL_SIZE="${XPATH_ELEMENTS[j++]}"
DRIVER="${XPATH_ELEMENTS[j++]}"
DATASTORE_ID="${XPATH_ELEMENTS[j++]}"
IMAGE_ID="${XPATH_ELEMENTS[j++]}"
TYPE_DISK="${XPATH_ELEMENTS[j++]}"
TM_MAD="${XPATH_ELEMENTS[j++]}"

#-------------------------------------------------------------------------------
# Create the snapshot and link it
#-------------------------------------------------------------------------------
ORIG_LV_NAME="/dev/vg-one-${DATASTORE_ID}/lv-one-image-${IMAGE_ID}"
LV_NAME="lv-one-vm-$VM_ID-$DISK_ID"
VG_NAME="vg-one-$DS_SYS_ID"
DEV="/dev/${VG_NAME}/${LV_NAME}"


# Execute lvcreate with a lock in the frontend
CREATE_CMD=$(cat <<EOF
    set -e -o pipefail
    $SUDO $SYNC
    set +e
    $SUDO $LVSCAN | grep "$DEV"
    if [ "x\$?" == "x0" ]; then
        set -e -o pipefail

        $SUDO $LVCHANGE -ay $DEV
    else
        set -e -o pipefail

        $SUDO $LVCREATE --wipesignatures n -L${SIZE}M -n $LV_NAME $VG_NAME
    fi
EOF
)



LOCK="tm-fs_lvm-${DS_SYS_ID}.lock"
exclusive "${LOCK}" "120 lvm_clone" ssh_exec_and_log "$DST_HOST" "$CREATE_CMD" \
    "Error creating LV named $LV_NAME"

CLONE_CMD=$(cat <<EOF
    set -e -o pipefail
    export PATH=$PATH:/sbin
    mkdir -p $DST_DIR
    pdp-one "$DS_DIR"
    pdp-one "$DST_DIR"

    $SUDO $LVCHANGE -ay $ORIG_LV_NAME
    if [[ "$DRIVER" == "raw" ]]; then
        $SUDO ${DD} if=$ORIG_LV_NAME of=$DEV bs=1M
    else
        $QEMU_IMG convert -O raw "$ORIG_LV_NAME" "$DEV"
    fi

    rm -f "$DST_PATH"
    ln -s "$DEV" "$DST_PATH"
EOF
)

ssh_exec_and_log "$DST_HOST" "$CLONE_CMD" \
            "Error cloning $ORIG_LV_NAME to $LV_NAME"

exit 0
