#! /bin/sh

# install_prereq: a script to install distribution-specific
# prerequirements

set -e

usage() {
  echo "$0: a script to install distribution-specific prerequirement"
  echo 'Revision: $Id: install_prereq 2733 2007-07-13 00:27:47Z tzafrir $'
  echo ""
  echo "Usage: $0:         Shows this message."
  echo "Usage: $0 test     Prints commands it is about to run."
  echo "Usage: $0 install  Really install."
}

PACKAGES_DEBIAN="build-essential libnewt-dev libusb-dev"
PACKAGES_RH="gcc newt-devel libusb-devel"
KVERS=`uname -r`

case "$1" in
test)    testcmd=echo ;;
install) testcmd='' ;;
'') usage; exit 0 ;;
*) usage; exit 1 ;;
esac



has_kernel_source() {
	test -r /lib/modules/$KVERS/build/.config
}

in_test_mode() {
  test "$testcmd" != ''
}

handle_debian() {
	# echo "# Distribution is Debian or compatible"
	kernel_package=''
	if ! has_kernel_source; then
		kernel_package="linux-headers-$KVERS"
		debian_release=`cat /etc/debian_version`
		case "$debian_release" in
		3.1) kernel_package="kernel-headers-$KVERS";;
		esac
		echo "# Kernel source not found. Installing $kernel_package"
	fi
	$testcmd apt-get install -y $PACKAGES_DEBIAN $kernel_package
}

handle_rh() {
	# echo "# Distribution is Debian or compatible"
	kernel_package=''
	if ! has_kernel_source; then
		kern_str='' # extra "kernel version"
		case $KVERS in
		*smp*) kern_str='-smp';;
		*PAE*) kern_str='-PAE';;
		*xen*) kern_str='-xen';;
		esac
		kernel_package="kernel$kern_str-devel-$KVERS"
		echo "# Kernel source not found. Installing $kernel_package"

		echo "# if you get an error for the following command, consider"
		echo "#"
		echo "#yum install -y kernel$kern_str kernel$kern_str-devel"
		echo "#"
		echo "# and then reboot to upgrade to the newly installed kernel."
	fi
	$testcmd yum install -y $PACKAGES_RH $kernel_package
}

if in_test_mode; then
	echo "#############################################"
	echo "## $1: test mode."
	echo "## Use the commands here to install your system."
	echo "#############################################"
fi

# handle the easy case of Debians first
if [ -r /etc/debian_version ]; then
  handle_debian
elif [ -r /etc/redhat-release ]; then
  handle_rh
fi

echo "#############################################"
echo "## $1 completed successfully"
if in_test_mode; then
	echo "## (in test mode)"
fi
echo "#############################################"
