#!/bin/bash
ORIGINAL_ARGS=("$@")

#  Includes
. $(miniade) || { echo "${0##*/}: ERROR: miniade failed (hint: run 'miniade' to see error)" >&2; exit 1; }

#  Configurable stuff

#  Other globals
BASE_DEVICE_MINOR=0
BASE_TCP_PORT=8790
LVM_VG_NAME=vg0
ZPOOL_NAME=zpool0

main()
{
    local MY_ARGS
    local PROGNAME

    #  Defaults for options
    REMOTE_HOST=
    TCP_PORT=
    VOL_NAME=
    VOL_SIZE=
    VOL_CREATION_MODE=lvm

    #  Process options
    special_opts_handler()
    {
        case $1 in
            --name=*)     VOL_NAME=${1#*=} ;;
            --size=*)     VOL_SIZE=${1#*=} ;;
            --name1=*)    PRIMARY_UNAME=${1#*=} ;;
            --name2=*)    SECONDARY_UNAME=${1#*=} ;;
            --ip1=*)      PRIMARY_IPADDR=${1#*=} ;;
            --ip2=*)      SECONDARY_IPADDR=${1#*=} ;;
            --remote=*)   REMOTE_HOST=${1#*=} ;;
            --tcp-port=*) TCP_PORT=${1#*=} ;;
            --vg=*)       VOL_CREATION_MODE=lvm
                          LVM_VG_NAME=${1#*=} ;;
            --zpool=*)    VOL_CREATION_MODE=zfs
                          ZPOOL_NAME=${1#*=} ;;
            --dev=*)      VOL_CREATION_MODE=none
                          DEV_PATH=${1#*=} ;;
            *)            return 1 ;;
        esac
    }
    miniade_process_options --help-handler=help --special-opts-handler=special_opts_handler MY_ARGS "$@" && set -- "${MY_ARGS[@]}"

    #  Process arguments
    [ $# = 0 ] || miniade_bad_usage

    #  Sanity checks and derivations
    miniade_get_progname PROGNAME
    [[ $VOL_CREATION_MODE =~ ^(lvm|zfs|none)$ ]] || miniade_bad_usage
    for VAR in VOL_NAME VOL_SIZE PRIMARY_UNAME SECONDARY_UNAME PRIMARY_IPADDR SECONDARY_IPADDR; do
        eval "[ \"X\$$VAR\" != X ]" || miniade_bad_usage
    done
    [ "X$REMOTE_HOST" = X ] || miniade_check_ssh_ok $REMOTE_HOST || miniade_error "$REMOTE_HOST: no unfettered ssh access"
    I_AM_PRIMARY_FLAG=$(if ip -o -4 addr | sed -rn 's/.*inet ([^\/]+).*/\1/p' | fgrep -xq $PRIMARY_IPADDR; then echo true; else echo false; fi)
    miniade_debug 10 "main: I_AM_PRIMARY_FLAG=$I_AM_PRIMARY_FLAG"
    HIGHEST_DEVICE_MINOR=$(cat /etc/drbd.d/*.res /dev/null 2>/dev/null | sed -nr "s/.*minor *([0-9]+).*/\\1/p" | sort -rn | head -1)
    case $HIGHEST_DEVICE_MINOR in
        '')     DEVICE_MINOR=$BASE_DEVICE_MINOR ;;
        [0-9]*) DEVICE_MINOR=$((HIGHEST_DEVICE_MINOR+1)) ;;
    esac
    if [ "X$TCP_PORT" = X ]; then
        HIGHEST_TCP_PORT=$(cat /etc/drbd.d/*.res /dev/null 2>/dev/null | sed -nr "s/.*address .*:([1-9][0-9]*).*/\\1/p" | sort -rn | head -1)
        case $HIGHEST_TCP_PORT in
            '')     TCP_PORT=$BASE_TCP_PORT ;;
            [1-9]*) TCP_PORT=$((HIGHEST_TCP_PORT+1)) ;;
        esac
    fi
    if [[ $VOL_SIZE =~ ^([1-9][0-9]*)([tgbTGB]?)$ ]]; then
        VOL_SIZE=${BASH_REMATCH[1]}
        VOL_SIZE_UNIT=${BASH_REMATCH[2]^^:-G}
    else
        miniade_error "$VOL_SIZE: invalid volume size (hint: format is <num>[unit])"
    fi
    miniade_debug 10 "main: DEVICE_MINOR=$DEVICE_MINOR, TCP_PORT=$TCP_PORT"

    #  Guts
    #echo "$(date --iso=seconds): $0" "${ORIGINAL_ARGS[@]}" >> $HISTFILE
    echo "#!/bin/bash" > /tmp/$PROGNAME.$$.sh
     
    if [ $VOL_CREATION_MODE = lvm ]; then
        miniade_info "$LVM_VG_NAME: checking VG exists ..."
        vgs $LVM_VG_NAME > /dev/null 2>&1 || miniade_error "$LVM_VG_NAME: not found (hint: run 'vgs $LVM_VG_NAME')"
        miniade_info "$VOL_NAME: checking LV doesn't exist already ..."
        LVS_STDERR=$(lvs --noheadings -o name /dev/$LVM_VG_NAME/$VOL_NAME 2>&1 > /dev/null) || true
        [[ $LVS_STDERR =~ Failed\ to\ find\ logical\ volume ]] || miniade_error "$VOL_NAME: LVs may exist already"
        miniade_info "$VOL_NAME: creating LV ..."
        #  If you thought the right option not to be asked about wiping DRBD signatures 
        #  would be '--wipesignatures=y' then you thought wrong. Just use '--yes'. Sheesh. 
        LVCREATE_CMDLINE="lvcreate --yes --size=$VOL_SIZE$VOL_SIZE_UNIT --name=$VOL_NAME $LVM_VG_NAME > /dev/null 2>&1"
        miniade_evaler "$LVCREATE_CMDLINE"
        echo "$LVCREATE_CMDLINE" >> /tmp/$PROGNAME.$$.sh
        DRBD_COMPONENT_DEVICE=/dev/$LVM_VG_NAME/$VOL_NAME
    elif [ $VOL_CREATION_MODE = zfs ]; then
        miniade_info "$ZPOOL_NAME: checking pool exists ..."
        zfs list $ZPOOL_NAME > /dev/null 2>&1 || miniade_error "$ZPOOL_NAME: not found (hint: run 'zfs list $ZPOOL_NAME')"
        miniade_info "$VOL_NAME: checking zvol doesn't exist already ..."
        ZFS_STDERR=$(zfs list $ZPOOL_NAME/$VOL_NAME 2>&1 > /dev/null) || true
        [[ $ZFS_STDERR =~ dataset\ does\ not\ exist ]] || miniade_error "$VOL_NAME: zvol may exist already"
        miniade_info "$VOL_NAME: creating zvol ..."
        ZFS_CMDLINE="zfs create -s -V $VOL_SIZE$VOL_SIZE_UNIT $ZPOOL_NAME/$VOL_NAME"
        miniade_evaler "$ZFS_CMDLINE"
        echo "$ZFS_CMDLINE" >> /tmp/$PROGNAME.$$.sh
        DRBD_COMPONENT_DEVICE=/dev/zvol/$ZPOOL_NAME/$VOL_NAME
    elif [ $VOL_CREATION_MODE = none ]; then
        DRBD_COMPONENT_DEVICE=$DEV_PATH
    fi

    miniade_info "$VOL_NAME: creating DRBD config ..."
    {
        echo "resource drbd_$VOL_NAME {"
        echo "  protocol  A;"
        echo "  device    /dev/drbd_$VOL_NAME minor $DEVICE_MINOR;"
        echo "  meta-disk internal;"
        echo "  disk      $DRBD_COMPONENT_DEVICE;"
        echo "  net {"
        echo "    #allow-two-primaries;"
        echo "    after-sb-0pri discard-zero-changes;"
        echo "    after-sb-1pri discard-secondary;"
        echo "    #after-sb-2pri disconnect;"
        echo "  }"
        echo "  on $PRIMARY_UNAME {"
        echo "    address $PRIMARY_IPADDR:$TCP_PORT;"
        echo "  }"
        echo "  on $SECONDARY_UNAME {"
        echo "    address $SECONDARY_IPADDR:$TCP_PORT;"
        echo "  }"
        echo "  handlers {"
        echo "    before-resync-target \"/sbin/drbdsetup \$DRBD_MINOR secondary\";"
        echo "    split-brain \"/usr/lib/drbd/notify-split-brain.sh root\";"
        echo "  }"
        echo "}"
    } > /tmp/$PROGNAME.$$.res
    { echo "cat > /etc/drbd.d/$VOL_NAME.res <<'EOF'"; cat /tmp/$PROGNAME.$$.res; echo "EOF"; } >> /tmp/$PROGNAME.$$.sh
    miniade_evaler "mv /tmp/$PROGNAME.$$.res /etc/drbd.d/$VOL_NAME.res"

    miniade_info "$VOL_NAME: initialising device ..."
    miniade_evaler "drbdadm -- --force create-md drbd_$VOL_NAME > /dev/null 2>&1"
    echo "drbdadm -- --force create-md drbd_$VOL_NAME > /dev/null 2>&1" >> /tmp/$PROGNAME.$$.sh
    miniade_evaler "drbdadm up drbd_$VOL_NAME > /dev/null"
    echo "drbdadm up drbd_$VOL_NAME > /dev/null" >> /tmp/$PROGNAME.$$.sh
    if $I_AM_PRIMARY_FLAG; then
        miniade_evaler "drbdadm -- --overwrite-data-of-peer primary drbd_$VOL_NAME"
    else
        echo "drbdadm -- --overwrite-data-of-peer primary drbd_$VOL_NAME" >> /tmp/$PROGNAME.$$.sh
    fi

    if [ "X$REMOTE_HOST" != X ]; then
        miniade_evaler "ssh -T $REMOTE_HOST < /tmp/$PROGNAME.$$.sh"
        miniade_evaler "rm /tmp/$PROGNAME.$$.sh"
    else
        miniade_warning "/tmp/$PROGNAME.$$.sh: run this file on the other node"
    fi
}

help()
{
    local PROGNAME

    miniade_get_progname PROGNAME
    echo "Usage: $PROGNAME [ <standard-options> ] [ --vg=<vol-group-name> | --zpool=<zpool-name> ] [ --remote=<other-cluster-node-hostname> ] [ --tcp-port=<tcp-port> ] --name=<vol-name> --size=<vol-size>[MGT] --name1=<primary-uname> --ip1=<primary-ipaddr> --name2=<secondary-uname> --ip2=<secondary-ipaddr>"
    exit 0
}

main "$@"