#!/bin/sh
#
# Based on the am-wrapper.pl script provided by MandrakeSoft
#
# This software may be freely redistributed under the terms of the GNU
# public license.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
#######################################################################
#
# Executes the correct autoconf version.
#
# - defaults to automake-1.8
# - runs automake-1.7 if:
#   - envvar WANT_AUTOMAKE is set to `1.7'
#     -or-
#   - `Makefile.in' was generated by automake-1.7
#     -or-
#   - 'aclocal.m4' contain AM_AUTOMAKE_VERSION, specifying the use of 1.7
# - runs automake-1.6 if:
#   - envvar WANT_AUTOMAKE is set to `1.6'
#     -or-
#   - `Makefile.in'
#     -or-
#   - 'aclocal.m4' contain AM_AUTOMAKE_VERSION, specifying the use of 1.6
# - runs automake-1.5 if:
#   - envvar WANT_AUTOMAKE is set to `1.5'
#     -or-
#   - `Makefile.in' was generated by automake-1.5
#     -or-
#   - 'aclocal.m4' contain AM_AUTOMAKE_VERSION, specifying the use of 1.5
# - runs automake-1.4 if:
#   - envvar WANT_AUTOMAKE is set to `1.4'
#     -or-
#   - `Makefile.in' was generated by automake-1.4
#     -or-
#   - 'aclocal.m4' contain AM_AUTOMAKE_VERSION, specifying the use of 1.4
#
#######################################################################

if [ "${0##*/}" = "am-wrapper.sh" ]; then
	echo "Don't call this script directly." >&2
	exit 1
fi

binary_1_4="${0}-1.4"
binary_1_5="${0}-1.5"
binary_1_6="${0}-1.6"
binary_1_7="${0}-1.7"
binary_1_8="${0}-1.8"
binary="${binary_1_8}"

#
# autodetect routine
#
if [ "${WANT_AUTOMAKE}" != "1.8" ]; then
	if [ "${WANT_AUTOMAKE}" = "1.7" ]; then
		binary="${binary_1_7}"
	elif [ "${WANT_AUTOMAKE}" = "1.6" ]; then
		binary="${binary_1_6}"
	elif [ "${WANT_AUTOMAKE}" = "1.5" ]; then
		binary="${binary_1_5}"
	elif [ "${WANT_AUTOMAKE}" = "1.4" ]; then
		binary="${binary_1_4}"
	else
		if [ -r "Makefile.in" ]; then
			confversion_mf=$(perl -ne 'if (/^# Makefile\.in generated (?:automatically )?by automake (\S{3})/) { print $1; exit; }' Makefile.in)
		fi
		if [ -r "aclocal.m4" ]; then
			confversion_ac=$(perl -ne 'if (/generated automatically by aclocal (\S{3})/) { print $1; exit; }' aclocal.m4)
			confversion_am=$(perl -ne 'if (/^\s*\[?AM_AUTOMAKE_VERSION\(\[?([^\)]{2}[0-9]?)[^\)]*\]?\)/) { print $1; exit; }' aclocal.m4)
		fi

		if [ "${confversion_mf}" = "1.7" -o "${confversion_ac}" = "1.7" -o "${confversion_am}" = "1.7" ]; then
			binary="${binary_1_7}"
		elif [ "${confversion_mf}" = "1.6" -o "${confversion_ac}" = "1.6" -o "${confversion_am}" = "1.6" ]; then
			binary="${binary_1_6}"
		elif [ "${confversion_mf}" = "1.5" -o "${confversion_ac}" = "1.5" -o "${confversion_am}" = "1.5" ]; then
			binary="${binary_1_5}"
		elif [ "${confversion_mf}" = "1.4" -o "${confversion_ac}" = "1.4" -o "${confversion_am}" = "1.4" ]; then
			binary="${binary_1_4}"
		fi
	fi
fi

if [ "${WANT_AMWRAPPER_DEBUG}" ]; then
	if [ "${WANT_AUTOMAKE}" ]; then
		echo "am-wrapper: DEBUG: WANT_AUTOMAKE is set to ${WANT_AUTOMAKE}" >&2
	fi
	echo "am-wrapper: DEBUG: will execute <$binary>" >&2
fi

#
# for further consistency
#
if [ "${binary}" = "${binary_1_8}" ]; then
	export WANT_AUTOMAKE="1.8"
elif [ "${binary}" = "${binary_1_7}" ]; then
	export WANT_AUTOMAKE="1.7"
elif [ "${binary}" = "${binary_1_6}" ]; then
	export WANT_AUTOMAKE="1.6"
elif [ "${binary}" = "${binary_1_5}" ]; then
	export WANT_AUTOMAKE="1.5"
elif [ "${binary}" = "${binary_1_4}" ]; then
	export WANT_AUTOMAKE="1.4"
fi

if [ ! -x "${binary}" ]; then
	# this shouldn't happen
	echo "am-wrapper: $binary is missing or not executable." >&2
	echo "            Please try emerging the correct version of automake." >&2
	exit 1
fi

exec "$binary" "$@"

echo "am-wrapper: was unable to exec $binary !?" >&2
exit 1