#! /bin/sh
#
# $Id$
#

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

set -e

usage() {
  echo "$0: a script to install distribution-specific prerequirement"
  echo 'Revision: $Id$'
  echo ""
  echo "Usage: $0:         Shows this message."
  echo "Usage: $0 test     Prints commands it is about to run."
  echo "Usage: $0 install  Really install."
}

# Basic build system:
PACKAGES_DEBIAN="build-essential"
# Asterisk: basic requirements:
PACKAGES_DEBIAN="$PACKAGES_DEBIAN libncurses-dev libz-dev libssl-dev"
# Asterisk: very useful addons:
PACKAGES_DEBIAN="$PACKAGES_DEBIAN libcurl-dev libspeex-dev libogg-dev libvorbis-dev libasound2-dev"
# Asterisk: nice-to-have addons:
PACKAGES_DEBIAN="$PACKAGES_DEBIAN libpq-dev unixodbc-dev libsqlite-dev"
# Not so nice addon:
PACKAGES_DEBIAN="$PACKAGES_DEBIAN libopenh323-dev"
# Extras for 1.4:
PACKAGES_DEBIAN="$PACKAGES_DEBIAN libsnmp-dev libiksemel-dev "

PACKAGES_RH="gcc gcc-c++ ncurses-devel openssl-devel"

KVERS=`uname -r`

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

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

# Fixme: should be done by apt and not by dpkg?
check_installed_debs() {
	 dpkg-query -W --showformat '${Status} ${Package}\n' "$@" 2>/dev/null \
	 | awk '/ not-installed/{print $4}'
}

# parsing the output of yum is close to impossible.
# We'll use rpm and hope for the best:
check_installed_rpms() {
	for pack in "$@"
	do
		if ! rpm -q $pack >/dev/null 2>/dev/null
		then echo $pack
		fi
	done
}

handle_debian() {
	# echo "# Distribution is Debian or compatible"
	extra_packs=`check_installed_debs $PACKAGES_DEBIAN`
	$testcmd apt-get install -y $extra_packs
}

handle_rh() {
	# echo "# Distribution is RedHat-based or compatible"
	extra_packs=`check_installed_rpms $PACKAGES_RH`
        # FIXME: is there yum with RHEL 4?
	$testcmd yum install -y $extra_packs
}

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

OS=`uname -s`
unsupported_distro=''

# A number of distributions we don't (yet?) support.
if [ "$OS" != 'Linux' ]; then
  echo >&2 "$0: Your OS ($OS) is currently not supported. Aborting."
  exit 1
fi

if [ -f /etc/gentoo-release ]; then
  unsupported_distro='Gentoo'
fi

if [ -f /etc/mandrake-release ]; then
  unsupported_distro='Mandriva'
fi

if [ -f /etc/SuSE-release ]; then
  unsupported_distro='SUSE'
fi

if [ -f /etc/slackware-version ]; then
  unsupported_distro='Slackware'
fi

if [ "$unsupported_distro" != '' ]; then
  echo >&2 "$0: Your distribution ($unsupported_distro) is currently not supported. Aborting."
  exit 1
fi

# The distributions we do support:
if [ -r /etc/debian_version ]; then
  handle_debian
elif [ -r /etc/redhat-release ]; then
  handle_rh
fi

if ! in_test_mode; then
  echo "#############################################"
  echo "## $1 completed successfully"
  echo "#############################################"
fi
