#!/bin/bash

# -------------------------------------------------------------------------- #
# Copyright 2002-2015, OpenNebula Project (OpenNebula.org), C12G Labs        #
#                                                                            #
# 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.                                             #
#--------------------------------------------------------------------------- #

###############################################################################
# This script is used to monitor the free and used space of a datastore
###############################################################################

# -------- Set up the environment to source common tools & conf ------------

if [ -z "${ONE_LOCATION}" ]; then
    LIB_LOCATION=/usr/lib/one
else
    LIB_LOCATION=$ONE_LOCATION/lib
fi

. $LIB_LOCATION/sh/scripts_common.sh

DRIVER_PATH=$(dirname $0)
source ${DRIVER_PATH}/../libfs.sh
source ${DRIVER_PATH}/ceph.conf

# -------- Get datastore arguments from OpenNebula core ------------

DRV_ACTION=$1
ID=$2

XPATH="${DRIVER_PATH}/../xpath.rb -b $DRV_ACTION"

unset i j XPATH_ELEMENTS

while IFS= read -r -d '' element; do
    XPATH_ELEMENTS[i++]="$element"
done < <($XPATH     /DS_DRIVER_ACTION_DATA/DATASTORE/TEMPLATE/BRIDGE_LIST \
                    /DS_DRIVER_ACTION_DATA/DATASTORE/TEMPLATE/POOL_NAME \
                    /DS_DRIVER_ACTION_DATA/DATASTORE/TEMPLATE/CEPH_USER)

BRIDGE_LIST="${XPATH_ELEMENTS[j++]}"
POOL_NAME="${XPATH_ELEMENTS[j++]:-$POOL_NAME}"
CEPH_USER="${XPATH_ELEMENTS[j++]}"

HOST=`get_destination_host`

if [ -z "$HOST" ]; then
    error_message "Datastore template missing 'BRIDGE_LIST' attribute."
    exit -1
fi

if [ -n "$CEPH_USER" ]; then
    CEPH="$CEPH --id ${CEPH_USER}"
fi

# ------------ Compute datastore usage -------------

MONITOR_SCRIPT=$(cat <<EOF
to_mb() {
    value=\$(echo "\$1" | sed 's/[^0123456789].*\$//g')
    units=\$(echo "\$1" | sed 's/^[0123456789]*//g' | tr '[:upper:]' '[:lower:]')

    case "\$units" in
        t|tb) value=\$(expr \$value \* 1024 \* 1024) ;;
        g|gb) value=\$(expr \$value \* 1024) ;;
        m|mb) value=\$value ;;
        k|kb) value=\$(expr \$value / 1024) ;;
        b|'') value=0 ;;
        *) value=0;;
    esac
    echo "\$value"
}

MAX_AVAIL=\$($CEPH df | grep "$POOL_NAME" | awk '{print \$5}')
USED=\$($CEPH df | grep "$POOL_NAME" | awk '{print \$3}')

USED_MB=\$(to_mb \$USED)
FREE_MB=\$(to_mb \$MAX_AVAIL)
TOTAL_MB=\$(expr \$USED_MB + \$FREE_MB)

echo "USED_MB=\$USED_MB"
echo "FREE_MB=\$FREE_MB"
echo "TOTAL_MB=\$TOTAL_MB"
EOF
)

MONITOR_DATA=$(ssh_monitor_and_log $HOST "$MONITOR_SCRIPT" 2>&1)
MONITOR_STATUS=$?

if [ "$MONITOR_STATUS" = "0" ]; then
    echo "$MONITOR_DATA" | tr ' ' '\n'
else
    echo "$MONITOR_DATA"
    exit $MONITOR_STATUS
fi

