#!/bin/bash
#
# Description:  Script for generating dxs filesystem by
#               cloning from rsync source for Diskless X Stations (v4.0)
#
# Author(s):    Nico Dietrich, 04-04-2006
#		Dirk von Suchodoletz <dirk@goe.net>, 31-01-2007
#               Michael Janczyk, <mj0>, 06-07-2006
#
# Copyright:    (c) 2003, 2006 - RZ Universitaet Freiburg
#
# Version:	0.2.1e
DEBUG=0

header() {
  echo
  echo "Welcome to the LD4 installation (please use lower case in input)"
  echo
}

# This function makes the directory of this script to the present working
# directory. It is called within precheck()
# Does also work when called by a symbolic link. Even works for nested links.
goto_script_dir()
{
  [ $DEBUG -ge 2 ] && echo "Aufgerufen wurde $0, checking if it is a link"
  calleddetails=`ls -l $0` # get the file flags (e.g. lrwxrwxrwx)
  [ $DEBUG -ge 2 ] && echo $calleddetails

  calleddir=${0%/*}  # Strip the filename from path
  [ $DEBUG -ge 2 ] && echo "Changing into directory of called scripts/links \
($calleddir)"
  cd $calleddir

  while index=`expr index "$calleddetails" "l"`;
        [ $index -eq 1 ]; do

    [ $DEBUG -ge 2 ] && echo "It is a link"
    target=`echo $calleddetails | awk '{print $NF}'`
    [ $DEBUG -ge 2 ] && echo "The target of the link is: $target"
    hasslash=`expr index "$target" "/"`
    if [ $hasslash -ne 0 ]; then
        targetpath=${target%/*} # extract the pathname
        [ $DEBUG -ge 2 ] && echo "Following link to $targetpath"
        cd $targetpath
    else
        [ $DEBUG -ge 2 ] && echo "It is in the same directory as the link"
    fi
    targetfile=`basename $target`
    [ $DEBUG -ge 2 ] && echo "The target file of the link is: $targetfile"
    calleddetails=`ls -l $targetfile` # get the file flags (e.g. lrwxrwxrwx)
    [ $DEBUG -ge 2 ] && echo $calleddetails
  done
  [ $DEBUG -ge 2 ] && pwd

}


# 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

  # switch pwd to this scripts location
  goto_script_dir

  # 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
  # but should be checked here, so the admin has just to restart
}

# bolean yes of different kinds of spelling
isyes () {
if [ "$1" = "yes" -o "$1" = "y" -o "$1" = "Y" -o "$1" = "Yes" ] ; then
  return 0
else
  return 1
fi
}

# 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\""
      ;;
      Dapper*|dapper*)
      eval "$2=\"6.06\""
      ;;
      Edgy*|edgy*|*)
      eval "$2=\"6.10\""
      ;;
    esac
    ;;
    Gentoo*|gentoo*)
    eval "$1=\"gentoo\""
    case "${!2}" in
      2005*)
      eval "$2=\"2005.1\""
      ;;
      2006*)
      eval "$2=\"2006.1\""
      ;;
    esac
    ;;
    SuSE*|suse*|Suse*|SuSe*|SUSE*|opensuse*|*)
    eval "$1=\"suse\""
    case "${!2}" in
      9*)
      eval "$2=\"9.3\""
      ;;
      10.0)
      eval "$2=\"10.0\""
      ;;
      10.1)
      eval "$2=\"10.1\""
      ;;
      10.2)
      eval "$2=\"10.2\""
      ;;
    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
#  # FIXME!! network autodetection seems not to work correctly

# ---> Variablenraten macht eigentlich nur hier Sinn, da sonst ja Werte vom
# letzten Mal
#  if ! [ -z "${netmask}" -a -z "${broadcast}" -a -z "${netname}" -a -z "${server}" ] ; then
#    ipcfg=( `ifconfig eth0 | grep "inet " | 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
  fi
  . .config

  [ -z $overwrite_configs ] && overwrite_configs="y"
  ask "Overwrite server configs (y) or write *.new files (n)? " overwrite_configs $overwrite_configs
  if [ "$overwrite_configs" = "no" -o "$overwrite_configs" = "n" -o \
       "$overwrite_configs" = "N" -o "$overwrite_configs" = "No" ] ; then
    overwrite_configs="no"
  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
  if [ -z ${client_distro} ] ; then
    client_distro=$server_distro
  fi
  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 ${client_distro}-$client_distro_ver as client distribution"

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

  . distro-specs/config-${server_distro}
  . distro-specs/config-client-${client_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

  # optional, komplexere Konfiguration via TGZ und nicht Skriptomatik
  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 $debuglevel
  [ -z "$debuglevel" ] && debuglevel=0
  while [ "101" -lt "$debuglevel" ]; do
    echo "The debug level has to be a number from 0 to 100"
    ask "Which debug level should be used? " debuglevel $debuglevel
    [ -z "$debuglevel" ] && debuglevel=0
  done

  # 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?
  ask "Would you like to use NBD? (y/N): " nbdyes $nbdyes
  if isyes $nbdyes ; then
    ask "Which kind of NBD export (ext2/squashfs)?: " nbdfs $nbdfs
  fi

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

copy_system() {
  # allow generic (identical over different versions) or specific exclude
  # files
  if [ -e distro-specs/exclude-${client_distro}-${client_distro_ver} ] ; then
    local file="distro-specs/exclude-${client_distro}-${client_distro_ver}"
  else
    local file="distro-specs/exclude-${client_distro}"
  fi
  # put specific an common exclude list into one file, add includes (+)
  # before excludes (-)
  cat $file distro-specs/exclude-common|grep -e "^+ " > /tmp/dxs-exclude-list
  cat $file distro-specs/exclude-common|grep -e "^- " >> /tmp/dxs-exclude-list

  test -d ${rootdir} || mkdir -p ${rootdir}
  echo -e "\n\nSyncing system now\nPlease enter root password of client \
machine\n"
  rsync -avDe ssh --delete --exclude-from=/tmp/dxs-exclude-list \
    ${rsyncsource} ${rootdir} || { echo "Rsync failed" ; exit 1 ; }
  rm /tmp/dxs-exclude-list
  # generate error message in case rsync didn't work and exit.

}

create_nbd() {
  if isyes $nbdyes ; then
    # TODO: mksquashfs (background process)
    if [ "$nbdfs" = "squashfs" ] ; then
      if ps aux|grep -v grep|grep mksquashfs &>/dev/null ; then
        echo "Found other mksquashfs process running, skipping this step."
      else
        echo -e "\nGenerating SquashFS image ${rootdir}.squashfs (ca. 30 min.)"
        if `which mksquashfs &>/dev/null` ; then
          mv ${rootdir}.squashfs ${rootdir}.squashfs.old
          echo "mksquashfs ${rootdir} ${rootdir}.squashfs"
          mksquashfs ${rootdir} ${rootdir}.squashfs &
        else
          echo -e "Tool 'mksquashfs' not found, skipping"
        fi
      fi
    else
      # to be extended
      # check for space occupied in ${rootdir}, add 10%, setup container
      # ext2 formatting ...
      echo -e "\nGenerating ..."
    fi
  fi
}

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=$j+1
    done
    ask "Please chose kernel(s) to create initial ramdisk(s) for.
First named will be the default boot. Separate multiple kernels w/ space." \
kernel_choice "${kernel_choice}"
  fi
  choice=( ${kernel_choice} )
  # make sure /$tftbootdir exists
  mkdir -p ${tftpbootdir}/pxelinux.cfg 2>/dev/null

  declare -i j=0
  # add nfs modules nevertheless
  fsmod=nfs
  # add nbd module and the selected filesystem ontop
  isyes "$nbdyes" && fsmod=$fsmod" nbd $nbdfs"
  # one big initrd or several smaller "specialized" ones!?

  while [ $j -lt ${#choice[@]} ] ; do
    current_kernel=${kernel[${choice[$j]}]#${rootdir}/boot/vmlinuz-}
    echo "Creating initialramfs for ${current_kernel}"
    current_initramfs=${tftpbootdir}/initrd-dxs-${current_kernel}
    [ -f ${current_initramfs} ] && rm ${current_initramfs}
    echo "mkdxsinitrd -f \"$fsmod\" -r ${rootdir} -k ${current_kernel} -i ${current_initramfs} -d ${debuglevel}"
    mkdxsinitrd -f "$fsmod" -r ${rootdir} -k ${current_kernel} \
      -i ${current_initramfs} -d ${debuglevel}

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

# 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 init.local ; do
    [ -d ${dxs_conf}/${dir} ] || mkdir -p ${dxs_conf}/${dir}
  done

  # copy the client configuration default file and replace root_pw -
  # machine-setup
  # echo "setting root password: ${root_pw}"
  sed -e "s,@@@root_pw@@@,'${root_pw}'," default_files/machine-setup.default \
    > ${dxs_cl_dir}/${dxs_client_conf}

  # creating new configuration files in $dxs_conf
  # dhcp
  sed -e "s,@@@server@@@,${server},g;s,@@@tftpbootdir@@@,${tftpbootdir},g" \
      -e "s,@@@netmask@@@,${netmask},g;s,@@@broadcast@@@,${broadcast},g" \
      -e "s,@@@rootdir@@@,${rootdir},g;s,@@@netname@@@,${netname},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 "#/etc/exports - file generated by $0\n\
# for backups of this file please check /etc/dxs directory\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" \
      -e "s,@@@pxe_passwd@@@,${pxe_passwd},g" \
      -e "s,@@@client_distro@@@,${client_distro},g" \
      -e "s,@@@client_distro_ver@@@,${client_distro_ver},g" \
      -e "s,@@@rootdir@@@,${rootdir},g" default_files/default \
         > ${dxs_conf}/${dxs_pxedefault_conf}-${timestamp}

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

    if [ $j -eq 0 ] ; then
      default_string="  MENU DEFAULT\n"
    else
      default_string=""
    fi
    # because of restricted length of kernel commandline put the initrd token
    # last (needed only for loading with pxelinux)
    echo -e "LABEL ${client_distro}-${current_kernel}\n${default_string}\
  MENU LABEL $j. ${client_distro}-${client_distro_ver} ${current_kernel} Diskless\n\
  KERNEL ${server}::vmlinuz-${current_kernel}\n\
  APPEND rootfs=nfs://${server}${rootdir} apic dhcp noldsc debug=$debuglevel vci=DXS \
  initrd=${server}::initrd-dxs-${current_kernel} \n\
  ipappend 1\n" >> ${dxs_conf}/${dxs_pxedefault_conf}-${timestamp}

    if isyes "$nbdyes" ; then
      j=$j+1
      # create configs for nbd/squashfs kernels too
      echo -e "LABEL ${client_distro}-${current_kernel}-nbd\n\
  MENU LABEL $j. ${client_distro}-${client_distro_ver} ${current_kernel} Diskless NBD\n\
  KERNEL ${server}::vmlinuz-${current_kernel}\n\
  APPEND rootfs=nbd://${server}:5000/${nbdfs} apic dhcp noldsc debug=$debuglevel elevator=\"noop\" vci=DXS \
  initrd=${server}::initrd-dxs-${current_kernel}\n\
  ipappend 1\n" >> ${dxs_conf}/${dxs_pxedefault_conf}-${timestamp}
    fi

    j=$j+1
  done

  # if files should not be overwritten keep them
  # in place and create files with ".new" extension
  if [ "$overwrite_configs" = "no" ] ; then
    extension=".new"
    keep="yes"
  fi

  for cfile in "${dxs_dhcpd_conf} ${dhcpd_conf}" \
               "${dxs_atftpd_conf} ${atftpd_conf}" \
               "${dxs_pxedefault_conf} ${tftpbootdir}/${pxedefault_conf}" \
               "${dxs_exports_conf} ${exports_conf}" ; do
    set -- $cfile

    # check if file changed
    lastfile=`ls -lt ${dxs_conf}/${1}* | sed -n "2,2s%.*"${1}"%"${1}"%p"`
    ! [ -z $lastfile ] && diff ${dxs_conf}/${1}-${timestamp} ${dxs_conf}/${lastfile} >/dev/null
    if [ $? -eq 0 ] ; then
      echo "Configuration file ${2} didn't change - leaving unchanged"
      rm ${dxs_conf}/${1}-${timestamp}
    else
      # backing up orginial files / create files with .new extension
      if [ -f ${2} -a ! -L ${2} ] ; then
        if [ -z "$keep" ] ; then
          echo "Copying old ${2} to ${2}.original"
          mv ${2} ${2}.original
        else
          echo "Keeping old ${2} and generate ${2}.new instead"
        fi
      elif [ -L ${2} ] ; then
        [ -z "$keep" ] && unlink ${2}
      fi
      # linking files
      # fixme!! if SuSE und DHCP dann Kopie statt Link
      if [ ${server_distro} = "suse" ] && echo ${dxs_conf}|\
        grep dhcp &>/dev/null; then
        rm ${2}${extension} &>/dev/null
	cp ${dxs_conf}/${1}-${timestamp} ${2}${extension}
      else
        ln -sf ${dxs_conf}/${1}-${timestamp} ${2}${extension}
      fi
    fi
  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"

# config directory for the server side
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"
# config directory for the client side
dxs_cl_dir="/var/opt/openslx/config/default/initramfs"
dxs_client_conf="machine-setup.pls-configure"

# Quick and dirty: rebuild the ramdisk  
if [ "x$1" = "x-g" ]; then
  echo "Creating initial ramdisk from last runs settings (if possible...)"
  precheck
  if [ -f .config ] ; then
    . .config
    create_initrd
    exit 0
  else
    echo "No previous settings found. Please configure your installation first"
  fi
fi

header
precheck #(run as root, rsync etc.)
configure
#do not sync if "-o" was specified
[ "$1" = "-o" ] || copy_system
create_nbd
create_initrd
setup_server
footer