#!/bin/bash

# -------------------------------------------------------------------------- #
# Copyright 2002-2026, 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.                                             #
#--------------------------------------------------------------------------- #

# mkimage size format host:remote_system_ds/disk.i vmid dsid
#   - size in MB of the image
#   - format for the image
#   - remote_system_ds is the path for the system datastore in the host
#   - vmid is the id of the VM
#   - dsid is the target datastore (0 is the system datastore)

SIZE=$1
FORMAT=$2
DST=$3
VM_ID=$4

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

DRIVER_PATH=$(dirname $0)

source $TMCOMMON
source ${DRIVER_PATH}/../../datastore/libfs.sh
source ${DRIVER_PATH}/../../etc/tm/fs_lvm/fs_lvm.conf
source ${DRIVER_PATH}/../../etc/datastore/datastore.conf

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

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

DS_SYS_ID=$(basename $(dirname $DST_DIR))
DST_DS_PATH="$(dirname $(dirname $(dirname $DST_PATH)))"
DISK_ID=$(basename ${DST_PATH} | cut -d. -f2)

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

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]/FS \
                            /VM/TEMPLATE/DISK[DISK_ID=$DISK_ID]/LVM_THIN_ENABLE)

FS="${XPATH_ELEMENTS[j++]}"
LVM_THIN_ENABLE="${XPATH_ELEMENTS[j++],,}"

#-------------------------------------------------------------------------------
# Create the logical volume and link it
#-------------------------------------------------------------------------------

POOL_NAME="lv-one-$VM_ID-pool"
LV_NAME="lv-one-$VM_ID-$DISK_ID"
VG_NAME="vg-one-$DS_SYS_ID"
DEV="/dev/${VG_NAME}/${LV_NAME}"

if [ -n "$FS" ] && ! contains "${SUPPORTED_FS}" "${FS}" ","; then
    log_error "Unsupported file system type: ${FS}. Supported types are: ${SUPPORTED_FS}"
    exit 1
fi

# Execute lvcreate with a lock in the frontend
CREATE_CMD=$(cat <<EOF
    set -e -o pipefail
    $SYNC
    $SUDO $LVSCAN
    if [ "$LVM_THIN_ENABLE" = 'yes' ]; then
        # If pool exists, extend it for the new disk. Otherwise, create it.
        if [ -n "\$($SUDO $LVS --noheading -S "vg_name = $VG_NAME && lv_name = $POOL_NAME")" ]; then
            $SUDO $LVEXTEND -L +${SIZE}M $VG_NAME/$POOL_NAME
        else
            # -ky is to enable activation skip, preventing possible data corruption for
            # example in HA situations
            # -Zy is for auto-zeroing thin volumes. It already defaults to 'y' but just in case...
            $SUDO $LVCREATE -ky -Zy -L ${SIZE}M --type thin-pool --thinpool $POOL_NAME $VG_NAME
            $SUDO $LVCHANGE -an $VG_NAME/$POOL_NAME
            $SYNC
        fi
        $SUDO $LVCREATE -ky --thin $VG_NAME/$POOL_NAME -V ${SIZE}M -n $LV_NAME
        $SUDO $LVCHANGE -ay -K $VG_NAME/$LV_NAME
    else
        $SUDO $LVCREATE --wipesignatures n -L${SIZE}M -n $LV_NAME $VG_NAME
    fi
    $SYNC
EOF
)

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

MKIMAGE_CMD=$(cat <<EOF
    set -e -o pipefail
    export PATH=/usr/sbin:/sbin:\$PATH

    mkdir -p $DST_DIR

    hostname -f >"${DST_DIR}/.host" || :

    # zero the volume
    if [ "${ZERO_LVM_ON_CREATE}" = "yes" ] && [ "$LVM_THIN_ENABLE" != 'yes' ]; then
        ${DD} if=/dev/zero of="${DEV}" bs=${DD_BLOCK_SIZE:-64k} 2> /dev/null || :
    fi

    [ "$FORMAT" = "swap" ] && mkswap ${DEV}

    if [ -n "$FS" ]; then
        FS_OPTS=$(eval $(echo "echo \$FS_OPTS_$FS"))
        $MKFS -t ${FS} ${FS_OPTS} ${DEV}
    fi

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

ssh_exec_and_log "$DST_HOST" "$MKIMAGE_CMD" \
        "Could not create image $DST_PATH"

exit 0
