#!/bin/bash
#  $HeadURL$ $LastChangedRevision$
set -e
{ [[ $0 =~ ^/ ]] && PROGNAME_FULL=$0; } || PROGNAME_FULL=$(cd $PWD/$(dirname $0) && pwd)/$(basename $0)
PROGNAME=$(basename $0)
#PROGNAME=${PROGNAME_FULL//\//_}

#  MODROOT
MODROOT=${MDI_MODROOT:-$(while [ ! -d lib/helpers -a $PWD != / ]; do cd ..; done; echo $PWD)}
[ -d $MODROOT/lib/helpers ] || { echo "$PROGNAME: ERROR: can't find components (do you need to set 'MDI_MODROOT'?)" >&2; exit 1; }

#  Load config and support functions
. $MODROOT/include/mdi.sh
. $MODROOT/etc/mdi.sh

#  Globals

main()
{
    local CMDLINE

    #  Defaults for options
    VERBOSELEVEL=2
    HELPER_HOOKS_FILE=$PROGNAME_FULL-hooks
    DISPLAY_PROGNAME=$(basename $(dirname $PROGNAME_FULL))
    RECURSE_FLAG=true

    #  Process options
    while [ "X$1" != X ]; do
        case $1 in
            #  Application-specific options
            --helper-hooks=*)      HELPER_HOOKS_FILE=${1#*=} ;;
            --progname=*)          DISPLAY_PROGNAME=${1#*=} ;;
            --recurse=*)           RECURSE_FLAG=${1#*=} ;;
            #  General options
            -v|--verbose)          VERBOSELEVEL=3 ;;
            -d)                    VERBOSELEVEL=$2; shift ;;
            --debug=*)             VERBOSELEVEL=${1#*=} ;;
            -h|--help)             usage 0 ;;
            --)                    shift; break ;;
            -*)                    usage ;;
            *)                     break ;;
        esac
        shift
    done

    #  Process arguments
    [ $# -ge 1 ] || usage
    MODE=$1; shift
    debug 10 "main: MODE=$MODE"
    case $MODE in
        edit|create|delete|list|purge|init) : ;;
        *)                                  usage ;;
    esac

    #  Sanity checks and derivations
    [ $RECURSE_FLAG = true -o $RECURSE_FLAG = false ] || usage

    #  Guts
    debug 10 "main: writing hooks file generic-helper ..."
    {
        echo "#  This file was generated by $PROGNAME on $(date)."
        echo
        cat <<'EOF'
#  Properties
MY_PRIVATE_ATTRIBUTES="uname status"
MY_PUBLIC_ATTRIBUTES=
MY_ATTRIBUTES="$MY_PRIVATE_ATTRIBUTES $MY_PUBLIC_ATTRIBUTES"
MY_HELPER_IDS=
for MY_ATTRIBUTE in ${MY_ATTRIBUTES^^}; do eval "$MY_ATTRIBUTE="; done

#  Defaults

#  Hooks

#  This function exists (1) to stop generic's hook, which lists the db, from running and (2) to produce
#  some debug output.
list_prologue()
{
    inherit SQLITE_CMD DB_FILE MY_ID
    local UNAMES

    UNAMES=$($SQLITE_CMD $DB_FILE "select group_concat(uname,' ') from attribute_values where helper == '$MY_ID' and attribute == 'status' and value == 'installing';")
    debug 10 "list_prologue: the following hosts are marked installing: $UNAMES; but nop-helper keeps mum about these"

    return 0
}

#  Overloads start here
EOF
        cat $HELPER_HOOKS_FILE
    } > /tmp/$PROGNAME.$$.helper-hooks
    CMDLINE="$LIB_DIR/helpers/generic-helper --recurse=$RECURSE_FLAG --progname=$DISPLAY_PROGNAME --debug=$VERBOSELEVEL --helper-hooks=/tmp/$PROGNAME.$$.helper-hooks $MODE $*"
    debug 10 "main: calling [$CMDLINE]"
    eval "$CMDLINE" || {
        RC=$?
        rm -f /tmp/$PROGNAME.$$.helper-hooks
        error "generic-helper failed; propogating error upwards ..."
        return $RC
    }
    rm -f /tmp/$PROGNAME.$$.helper-hooks
}

usage()
{
    local RC

    RC=${1:-1}

    {
        echo "Usage:   $DISPLAY_PROGNAME [ <options> ] { edit <host> | create <host> | delete <host> | purge | init | list }"
        echo
    } | if [ $RC = 0 ]; then
        cat
    else
        cat >&2
    fi

    exit $RC
}

main "$@"