#! /bin/sh
#
# Description:  Script for generating dxs filesystem by
#               cloning from rsync source for Diskless X Stations (v4.0)
#
# Author(s):    Nico Dietrich
#		Dirk von Suchodoletz <dirk@goe.net>, 02-11-2005
#
# Copyright:    (c) 2003, 2005 - RZ Universitaet Freiburg
#


header() {
  echo
  echo "Welcome to the LD4 installation"
  echo
}


# check needed things for installation
precheck() {
  # check if running as root
  if [ "`id -u`" != "0" ]; then
    echo -e "\nYou don't have the needed permission. Please rerun as root user!\n"
    exit 1
  fi

  # check for existing programs:
  # rsync (server-side)
  which rsync >/dev/null
  if [ $? != 0 ] ; then
    echo -e "\nYou need to install rsync on server side before installing!\n"
    exit 1
  fi

  # ssh, rsync (referenz-system-side) -> not possible in precheck

  # nfs-kernel-server, atftpd 
  #  -> not needed for installation
}


# ask question variable_name default_value
ask() {
  echo
  echo "$1"
  echo -n "* [ $3 ] "
  read userinput
  if [ -z "$userinput" ] ; then
    local back=$3
  else
    local back="$userinput"
  fi
  eval "$2=\"$back\""
  sed -e '/'$2'=.*/d' -i .config
  echo "$2=\"$back\"" >> .config
}


distro_check() {
  case "${!1}" in
    Debian*|debian*|Sarge*|sarge*)
    eval "$1=\"debian\""
    case "${!2}" in
      Sarge*|sarge*|3.1*|*)
      eval "$2=\"3.1\""
      ;;
    esac
    ;;
    Ubuntu*|ubuntu*)
    eval "$1=\"ubuntu\""
    case "${!2}" in
      Breezy*|breezy*|*)
      eval "$2=\"5.10\""
      ;;
    esac
    ;;
    Gentoo*|gentoo*)
    eval "$1=\"gentoo\""
    case "${!2}" in
      2005*|*)
      eval "$2=\"2005.1\""
      ;;
    esac
    ;;
    SuSE*|suse*|Suse*|SuSe*|SUSE*|*)
    eval "$1=\"suse\""
    case "${!2}" in
      9*)
      eval "$2=\"9.3\""
      ;;
      10.0)
      eval "$2=\"10.0\""
      ;;
      10*|*)
      eval "$2=\"10.1\""
      ;;
    esac
    ;;
  esac
}

# what do we do here??
configure() {
  export LANG="c"

  if [ -f .config ] ; then
    echo -n "Use values from last installation? [Y/n] "
    read userinput
    if [ "x$userinput" = "xn" ] ; then
      cp .config.default .config
    fi
  else
    cp .config.default .config
  fi
  . .config

  # FIXME!! network autodetection seems not to work correctly
  if ! [ -z "${netmask}" -a -z "${broadcast}" -a -z "${netname}" -a -z "${server}" ] ; then
    ipcfg=( `ifconfig eth0 | grep "inet addr" | sed -e "s,[a-zA-Z]*:,,g"` )
    netmask=${ipcfg[3]}
    broadcast=${ipcfg[2]}
    # quickhack (more intelligent solution needed ...)
    netname=`route -n | grep -m 1 eth0 | grep -v "UG" | awk '{ print $1 }'`
    server=${ipcfg[1]}
  fi


  # try to detect server architecture
  if [ -z "${server_distro}" ] ; then
    for i in /bin/lsb_release /usr/bin/lsb_release; do
      if [ -e $i ] ; then
        $i > /dev/null 2>&1 || break
        server_distro=`. $i -i | sed "s/.*\t//"`
        server_distro_ver=`. $i -r | sed "s/.*\t//"`
        break
      fi
    done
  fi

  # if still no distro name set, try to find it using significant files
  if [ -z "${server_distro}" ] ; then
    if [ -e ${rootdir}/etc/SuSE-release ] ; then
      server_distro=suse
      server_distro_ver=`grep "VERSION" /etc/SuSE-release | sed "s/.*= //"`
    elif [ -e /etc/lsb-release ] ; then
      . /etc/lsb-release
      server_distro=${DISTRIB_ID}
      server_distro_ver=${DISTRIB_RELEASE}
    elif [ -e /etc/debian_version ] ; then
      server_distro=debian
      server_distro_ver=`cat /etc/debian_version`
    fi
  fi

  # das grosse frage-antwort-spiel:
  ask "Server distribution (e.g. debian): " server_distro ${server_distro}
  #ask "Server distribution version: " server_distro_ver ${server_distro_ver}
  distro_check server_distro server_distro_ver
  echo "Using ${server_distro} as server distribution"

  # ask for client distro
  ask "Client distribution (e.g. debian): " client_distro ${client_distro}
  ask "Client distribution version (numerical - e.g. 3.1): " client_distro_ver ${client_distro_ver}
  distro_check client_distro client_distro_ver
  echo "Using ${client_distro} as client distribution"

  if [ -z ${rootdir} ] ; then
    rootdir="/nfsroot/"${client_distro}-${client_distro_ver}
  fi

  . distro-specs/config-${server_distro}

  ask "Path for client system: " rootdir $rootdir
  ask "Path for tftpboot: " tftpbootdir $tftpbootdir
  ask "Which network do you want to use for DXS? (A.B.C.0) " netname $netname
  ask "Which netmask should be used? (255.B.C.0): " netmask $netmask
  ask "What is your servers IP for NFS, DHCP and TFTP? " server $server
  # noetig??
  ask "Broadcast Address: " broadcast $broadcast

  # evtl. optional? --> besser in ein komplett eigenes Setup-Skript fuer
  # machine-setup
  ask "Where automount home directories from? (A.B.C.D:/home-dir)" amt $server":/home"

  # more information here!! set useful default
  ask "Which debug level should be used? " debuglevel $debuglevel

  # wo ist das referenzsystem? - was ist default ???
  if [ -z ${rsyncsource} ] ; then rsyncsource="localhost:/" ; fi
  ask "IP + Path to reference system: " rsyncsource $rsyncsource

  # dns-server
  # domain-name
  # evtl. ntp-server

  # which kernel(s) to use to generate initial ramdisk(s)
  # list available kernels and allow to chose from

  # nfs / nbd / squash-fs?


  # password for pxeboot-menu (caution: you can easily retrieve it in clear
  # text!!)
  pxe_passwd="master"
}


copy_system() {
  echo -e "\n\nSyncing system now\nPlease enter root password of client machine\n"
  rsync -avDe ssh --delete --exclude-from=distro-specs/exclude-${client_distro}-${client_distro_ver} ${rsyncsource} ${rootdir} || { echo "Rsync failed" ; exit 1 ; }

  # generate error message in case rsync didn't work and exit.

  # TODO: mksquashfs (background process)   
}

create_initrd() {
  # find existing kernels
  declare -i i=0
  for kern in `find ${rootdir}/boot |grep vmlinuz` ; do
    if ! [ -L $kern ] ; then
      kernel[$i]=$kern
      i=$i+1
    fi
  done

  if [ $i -eq 0 ] ; then
    echo "No kernels found in ${rootdir}/boot, so no initial ramdisk is created and linked to ${tftpbootdir}."
    kernel_choice=""
  elif [ $i -eq 1 ] ; then
    echo "Found one kernel in ${rootdir}/boot."
    kernel_choice="0"
  else
    echo -e "\n\nThis is a list of existing kernels in your client OS: \n"
    declare -i j=0
    while [ $j -lt $i ] ; do
      echo "$j: ${kernel[$j]}"
      j=$j+1
    done
    ask "Please chose kernels to create initial ramdisks for (space separated numbers) " kernel_choice ${kernel_choice}
  fi
  choice=( ${kernel_choice} )
  
  # make sure /$tftbootdir exists
  mkdir -p ${tftpbootdir}
  
  declare -i j=0
  # FIXME: mkdxsinitrd currently wants to run from own directory
  # ugly workaround...
  cd ../initrd
  while [ $j -lt ${#choice[@]} ] ; do
    current_kernel=${kernel[$j]#${rootdir}/boot/vmlinuz-}
    echo "Creating initial ramdisk for ${current_kernel}"
    current_initrd=${tftpbootdir}/initrd-dxs-${current_kernel}
    [ -f ${current_initrd} ] && rm ${current_initrd} 
    ./mkdxsinitrd -r ${rootdir} -k ${current_kernel} -i ${current_initrd}

    ln -sf ${kernel[$j]} ${tftpbootdir}/vmlinuz-${current_kernel}
    j=$j+1
  done
  cd - 
}

# setting up server site configuration files etc.
setup_server () {
  echo -e "\n\nSetting up server configuration\n"

  timestamp=`date +%Y%m%d-%H%M`

  # creating central dxs configuration directory structure if it doesn't exist
  for dir in dhcp nfs atftpd pxelinux client.cfg ; do
    [ -d ${dxs_conf}/${dir} ] || mkdir -p ${dxs_conf}/${dir}
  done

  # copy the client configuration default file - machine-setup
  cp default_files/machine-setup_default \
    ${client_conf}

  # creating new configuration files in $dxs_conf  
  # dhcp
  sed -e "s,@@@server@@@,${server},g;s,@@@netname@@@,${netname},g;s,@@@netmask@@@,${netmask},g;s,@@@broadcast@@@,${broadcast},g" default_files/dhcpd.conf > ${dxs_conf}/${dxs_dhcpd_conf}-${timestamp}
  # TODO: sed -e @@@example1@@@, netname+1 etc. - which ip addresses are safe to use?

  # atftpd
  sed -e "s,@@@tftpbootdir@@@,${tftpbootdir}," default_files/${atftpd_conf_name} > ${dxs_conf}/${dxs_atftpd_conf}-${timestamp}

  # nfs
  echo -e "# Bla Blub\n \
  # NFS export entry for DXS\n\
  ${rootdir} ${netname}/${netmask}(ro,no_root_squash,async)" >> ${dxs_conf}/${dxs_exports_conf}-${timestamp}

  # pxe
  [ -d ${tftpbootdir} ] || mkdir -p ${tftpbootdir} 
  rsync -a --exclude=.svn default_files/tftpboot/* ${tftpbootdir}

  sed -e "s,@@@server@@@,${server},g;s,@@@tftpbootdir@@@,${tftpbootdir},g;s,@@@pxe_passwd@@@,${pxe_passwd},g;s,@@@client_distro@@@,${client_distro},g;s,@@@client_distro_ver@@@,${client_distro_ver},g;s,@@@rootdir@@@,${rootdir},g" default_files/default > ${dxs_conf}/${dxs_pxedefault_conf}-${timestamp}

  declare -i j=0
  while [ $j -lt ${#choice[@]} ] ; do
    current_kernel=${kernel[$j]#${rootdir}/boot/vmlinuz-}
    current_initrd=${tftpbootdir}/initrd-dxs-${current_kernel}

    if [ $j -eq 0 ] ; then
      default_string="       MENU DEFAULT\n"
    else
      default_string=""
    fi
    echo -e "LABEL ${client_distro}-${current_kernel}\n${default_string} \
      MENU LABEL $j. ${client_distro}-${client_distro_ver} ${current_kernel} Diskless\n \
      KERNEL ${server}::${tftpbootdir}/vmlinuz-${current_kernel}\n \
      APPEND nfsroot=${server}:${rootdir} initrd=${server}::${tftpbootdir}/initrd-dxs-${current_kernel} apic dhcp noldsc vci=DXS\n \
      ipappend 1\n\n" >> ${dxs_conf}/${dxs_pxedefault_conf}-${timestamp}

    j=$j+1
  done
  
  
  # backing up original files
  for cfile in \
    ${dhcpd_conf} ${atftpd_conf} ${exports_conf} \
    ${tftpbootdir}/${pxedefault_conf} ${client_conf} ; do
    if [ -f ${cfile} -a ! -L ${cfile} ] ; then
      echo "Copying old ${cfile} to ${cfile}.original"
      mv ${cfile} ${cfile}.original
    elif [ -L ${cfile} ] ; then 
      unlink ${cfile}
    fi
  done

  # linking files
  for cfile in "${dxs_dhcpd_conf} ${dhcpd_conf}" "${dxs_atftpd_conf} ${atftpd_conf}" "${dxs_exports_conf} ${exports_conf}" "${dxs_pxedefault_conf} ${tftpbootdir}/${pxedefault_conf}" ; do
    set -- $cfile
    ln -s ${dxs_conf}/${1}-${timestamp} ${2}
  done

}



footer() {
  echo -e "\nPlease assure to restart atftpd, nfs-kernel-server and dhcpd!\n"
  echo -e "\nInstallation finished.\n"

  # TODO: tell user things he's got to configure afterwards - point to README
  #  * in dhcpd.conf - put in clients mac and ip addresses
  #  * make services start (automatically at server boot)

}




## ------ MAIN ------ ##

pxedefault_conf="pxelinux.cfg/default"

dxs_conf="/etc/dxs/"
dxs_dhcpd_conf="dhcp/dhcpd.conf"
dxs_atftpd_conf="atftpd/atftpd"
dxs_exports_conf="nfs/exports"
dxs_pxedefault_conf="pxelinux/default"




header
precheck #(run as root, rsync etc.)
configure
copy_system
create_initrd
setup_server
footer