#!/bin/bash
set -e
PROGNAME=$(basename $0)
#  $HeadURL: http://sos16-vip/svn/kickstart/trunk/bin/defaults-dumper $ $LastChangedRevision: 669 $

#  Load libraries
. $(dirname $0)/../include/mkdi.sh

main()
{
    local TARGET_HOSTNAME TARGET_MACADDR TARGET_IPADDR

    #  Defaults for options
    VERBOSELEVEL=2

    #  Process options
    while [ "X$1" != X ]; do
        case $1 in 
            #  Application specific options
            --target-hostname=*) TARGET_HOSTNAME=${1#*=} ;;
            --target-ipaddr=*)   TARGET_IPADDR=${1#*=} ;;
            --target-macaddr=*)  TARGET_MACADDR=${1#*=} ;;
            #  General options
            --help|-h)           usage 0 ;;
            --verbose|-v)        VERBOSELEVEL=3 ;;
            -d)                  VERBOSELEVEL=$2; shift ;;
            --debug=*)           VERBOSELEVEL=${1#*=} ;;
            --)                  shift; break ;;
            -*)                  usage ;;
            *)                   break ;; 
        esac
        shift
    done

    #  Process arguments
    [ $# -ge 1 ] || usage
    MODE=$1; shift
    debug 10 "main: MODE=$MODE"

    #  Guts
    case $MODE in
        create) create --target-hostname=$TARGET_HOSTNAME --target-macaddr=$TARGET_MACADDR --target-ipaddr=$TARGET_IPADDR "$@" || return $? ;;
        delete) delete --target-hostname=$TARGET_HOSTNAME --target-macaddr=$TARGET_MACADDR --target-ipaddr=$TARGET_IPADDR "$@" || return $? ;;
        list)   list "$@" || return $? ;;
        purge)  purge "$@" || return $? ;;
        *)      usage ;;
    esac

    return 0
}

create()
{
    local TARGET_HOSTNAME TARGET_MACADDR TARGET_IPADDR

    #  Process options
    while [ "X$1" != X ]; do
        case $1 in
            #  Application specific options
            --target-hostname=*) TARGET_HOSTNAME=${1#*=} ;;
            --target-ipaddr=*)   TARGET_IPADDR=${1#*=} ;;
            --target-macaddr=*)  TARGET_MACADDR=${1#*=} ;;
            #  General options
            --)                  shift; break ;;
            -*)                  internal "create: $1: invalid option" ;;
            *)                   break ;; 
        esac
        shift
    done

    #  Process arguments
    [ $# = 0 ] || internal "create: $#: wrong arg count"
    
    #  Create entry
    info "creating DHCP reservation ..."
    create_or_delete --target-hostname=$TARGET_HOSTNAME --target-macaddr=$TARGET_MACADDR --target-ipaddr=$TARGET_IPADDR create || return $?

    return 0
}

delete()
{
    local TARGET_HOSTNAME TARGET_MACADDR TARGET_IPADDR

    #  Process options
    while [ "X$1" != X ]; do
        case $1 in
            #  Application specific options
            --target-hostname=*) TARGET_HOSTNAME=${1#*=} ;;
            --target-ipaddr=*)   TARGET_IPADDR=${1#*=} ;;
            --target-macaddr=*)  TARGET_MACADDR=${1#*=} ;;
            #  General options
            --)                  shift; break ;;
            -*)                  internal "delete: $1: invalid option" ;;
            *)                   break ;;
        esac
        shift
    done

    #  Process arguments
    [ $# = 0 ] || internal "delete: $#: wrong arg count"
   
    #  Delete entry
    info "deleting DHCP reservation ..."
    create_or_delete --target-hostname=$TARGET_HOSTNAME --target-macaddr=$TARGET_MACADDR --target-ipaddr=$TARGET_IPADDR delete || return $?

    return 0
}

create_or_delete()
{
    local TARGET_HOSTNAME TARGET_MACADDR TARGET_IPADDR
    local MODE LINE DHCPD_OUTPUT

    #  Process options
    while [ "X$1" != X ]; do
        case $1 in
            #  Application specific options
            --target-hostname=*) TARGET_HOSTNAME=${1#*=} ;;
            --target-ipaddr=*)   TARGET_IPADDR=${1#*=} ;;
            --target-macaddr=*)  TARGET_MACADDR=${1#*=} ;;
            #  General options
            --)                  shift; break ;;
            -*)                  internal "create_or_delete: $1: invalid option" ;;
            *)                   break ;;
        esac
        shift
    done

    #  Process arguments
    [ $# = 1 ] || internal "create_or_delete: $#: wrong arg count"
    MODE=$1
    
    #  Sanity checks and derivations
    validate_vars MODE TARGET_HOSTNAME TARGET_IPADDR TARGET_MACADDR || return $?
    debug 10 "main: MODE=$MODE, TARGET_HOSTNAME=$TARGET_HOSTNAME, TARGET_IPADDR=$TARGET_IPADDR, TARGET_MACADDR=$TARGET_MACADDR"
    LINE="        host $TARGET_HOSTNAME { hardware ethernet $TARGET_MACADDR; fixed-address $TARGET_IPADDR; } # $TARGET_HOSTNAME"

    #  Guts
    if [ $MODE = create ]; then
        ! grep " host $TARGET_HOSTNAME " /etc/dhcp3/dhcpd.conf > /dev/null || { error "$TARGET_HOSTNAME: entry present already (do you need to run 'mkdi delete $TARGET_HOSTNAME' first?)"; return 1; }
        debug 10 "create_or_delete: creating entry ..."
        perl -pi -e "s/^(        #  INSTALL-SERVER ENTRIES START HERE)\$/\$1\n$LINE/" /etc/dhcp3/dhcpd.conf
 
    elif [ $MODE = delete ]; then
        debug 10 "create_or_delete: deleting entry ..."
        perl -0777 -pi -e "s/^(        #  INSTALL-SERVER ENTRIES START HERE\n.*?)^$LINE\n(.*?^        #  INSTALL-SERVER ENTRIES END HERE)/\$1\$2/msg" /etc/dhcp3/dhcpd.conf
    fi
    DHCPD_OUTPUT=$(/etc/init.d/dhcp3-server restart 2>&1) || { error "dhcpd: failed (output was: $DHCPD_OUTPUT)"; return 1; }

    return 0
}

purge()
{
    #  Guts
    perl -0777 -pi -e "s/^(        #  INSTALL-SERVER ENTRIES START HERE\n)^.*?\n(^        #  INSTALL-SERVER ENTRIES END HERE)/\$1\$2/msg" /etc/dhcp3/dhcpd.conf
    DHCPD_OUTPUT=$(/etc/init.d/dhcp3-server restart 2>&1) || { error "dhcpd: failed (output was: $DHCPD_OUTPUT)"; return 1; }

    return 0
}

list()
{
   #  Process options
    while [ "X$1" != X ]; do
        case $1 in
            #  Application specific options
            #  General options
            --)                  shift; break ;;
            -*)                  internal "list: $1: invalid option" ;;
            *)                   break ;;
        esac
        shift
    done

    #  Process arguments
    [ $# = 0 ] || internal "list: $#: wrong arg count"

    #  Guts
    sed -n "s/^ *\(.*; } #.*\)/\1/p" /etc/dhcp3/dhcpd.conf

    return 0
}

usage()
{
    local RC

    RC=${1:-1}

    {
        echo "Usage: $PROGNAME [ <options> ] { create <hostname> | delete <hostname> | list }"
        echo
    } | if [ $RC = 0 ]; then
        cat
    else
        cat >&2
    fi

    exit $RC
}

main "$@"