#!/bin/bash

#set -x

error=0 ; trap "error=$((error|1))" ERR

# apt-get: be quiet!
APTOPTIONS="-q=2"


# check whether the environment is still valid
if [ x${FAI} = x ] ; then
	echo "ERROR: \$FAI is empty!"
	exit 10
fi

if [ x${target} = x ] ; then
	echo "ERROR: \$target is empty!"
	exit 11
fi

# Safeguard: test whether /home/_ablage exists and is usable
if [ ! -e ${target}/home/_ablage ] ; then
	mkdir -p ${target}/home/_ablage
fi

if [ ! -d ${target}/home/_ablage ] && [ -w ${target}/home/_ablage ] ; then
  echo "ERROR: ${target}/home/_ablage is not a directory or is not writeable! Exiting with error."
  exit 1
fi

ARCH=$(${ROOTCMD} uname -m)
# transform old style arch definitions
case ${ARCH} in
	"i686")
		ARCH="x86_32"
		XENVERS="i386"
		;;
	"amd64")
		ARCH="x86_64"
		XENVERS="amd64"
		;;
	"x86_32")
		XENVERS="i386"
		;;
	"x86_64")
		XENVERS="amd64"
		;;
	*)
		echo "ERROR: this is not a x86 compliant architecture!"
		exit 1
		;;
esac

# copy XenTools software package
cp -a ${FAI}/software/xentools ${target}/home/_ablage/

# actually I just want to use the xen-guest-utilities package
# XenSource provides a 32bit kernel image, but their update strategy seems rather lacking
XENUTILSPKG=$(${ROOTCMD} find /home/_ablage/xentools/ -name "xe-guest*${XENVERS}.deb")
if [ -r ${target}/${XENUTILSPKG} ] ; then
	${ROOTCMD} dpkg -i ${XENUTILSPKG}		# somehow this causes errors ("unary operation expected")
else
	echo "WARNING: I didn't find a suitable xe-guest-utilities package or couldn't access it!"
fi

cat > ${target}/etc/apt/sources.list.d/xensource.list << EOT
deb     http://abelia.infrastruktur.aul.t-online.de:9999/xensource/debian/ etch main
deb-src http://abelia.infrastruktur.aul.t-online.de:9999/xensource/debian/ etch main
EOT

# XenTools adds a new apt-source -> update, but be quiet about it
${ROOTCMD} apt-get update ${APTOPTIONS}


# Attention: XenSource and Debian use a slightly different kernel naming scheme!
#            vmlinuz-xenu-2.6.18.xs4.1.0.1168.6013 vs vmlinuz-2.6.18-6-xen-amd64
# XenSource doesn't provide 64 bit kernels

case $(lsb_release -i|cut -f 2) in
	"Debian")
		# no special kernel parameters necessary (yet)
		XENKERNELOPTS=""			
		;;
	"Ubuntu")
		# we need to append this to the kernelparamaters or else there's no login possible @ Xen Console
		XENKERNELOPTS=" xencons=tty"	# don't remove the leading whitespace!
		
		# anyone assuming /bin/sh to be a bash deserves to get bitten!
		for SCRIPT in $(find $target/usr/sbin/ -name "xe-*") ; do
			TMPFILE="/tmp/$(basename ${SCRIPT}).tmp"
			cp ${SCRIPT} ${TMPFILE}
			sed -e "s'^#! */bin/sh'#! /bin/bash'" ${TMPFILE} > ${SCRIPT}
		done
		;;
	"Suse Linux")
		echo "90_xentools: SuSE found. No action defined (yet)."
		;;
	*)
		# undefined. maybe SUSE Linux
		;;
esac

# identify installed xen kernel (there should be only one kernel available), ignore XenSource Kernels
XENKERNELFILE=$(find ${target}/boot -name "vmlinuz-2*xen*")  # /target/boot/vmlinuz-xenu-2.6.18.xs4.1.0.1168.6013	| /target/boot/vmlinuz-2.6.18-6-xen-amd64
XENKERNEL=$(basename ${XENKERNELFILE})                   # vmlinuz-xenu-2.6.18.xs4.1.0.1168.6013		| vmlinuz-2.6.18-6-xen-amd64
XENKERNELVERS=$(echo ${XENKERNEL}|sed -e "s/vmlinuz-//") # xenu-2.6.18.xs4.1.0.1168.6013			| 2.6.18-6-xen-amd64


# !! WARNING !!

# make sure everything is peachy!

# Make. Sure. Everything. Is. Peachy. !

# We do NOT want grub_update to be run after this point!
# If your menu.lst does not contain the xen kernels then
# grub_update has been run and overwritten the config file!

# Check /tmp/fai/error.log for grub- and kernelimage-related
# errors!

# !! WARNING !!


# save the old config file
cp -p ${target}/boot/grub/menu.lst ${target}/boot/grub/menu.lst_novirt

# rewrite grub config accordingly (XenSource Xen kernel => without initrd)
sed -e "s/XENKERNELVERS/${XENKERNELVERS}/g" ${FAI}/files/menu.lst|sed -e "s/XENKERNEL/${XENKERNEL}${XENKERNELOPTS}/g" | sed -e "s/DISTRIB/$(lsb_release -i|cut -f2)/g"|grep -v "savedefault" > ${target}/boot/grub/menu.lst

## if in doubt enable this command to check whether a correct config has been written
#cp ${target}/boot/grub/menu.lst ${target}/boot/grub/menu.lst_checkme

# harddisks change from hd[abcd] to xvd[abcd], change /etc/fstab accordingly
# ToDo: consider UUIDs/labels for mounting
cp -p ${target}/etc/fstab ${target}/etc/fstab.orig				# preserve ownership and permissions
sed -e "s'^/dev/hd'/dev/xvd'g" ${target}/etc/fstab.orig > ${target}/etc/fstab
		
exit $error