#!/bin/sh
# small helper to extract information form *.ent files

BASEDIR="$(readlink -f "$(dirname $0)")"

getcurrent() {
	# search for an exact match to use the correct sources.list example
	cd $BASEDIR
	DISTROS="$(find . -mindepth 1 -maxdepth 1 -type d | cut -d'/' -f 2)"
	for DISTRO in $DISTROS; do
		if dpkg-vendor --is $DISTRO; then
			echo $DISTRO
			return 0
		fi
	done

	# if we haven't found a specific, look for a deriving
	# we do ubuntu and debian last as those are the biggest families
	# and would therefore potentially 'shadow' smaller families
	# (especially debian as it sorts quiet early)
	for DISTRO in $DISTROS; do
		if [ "$DISTRO" = 'debian' -o "$DISTRO" = 'ubuntu' ]; then continue; fi
		if dpkg-vendor --derives-from $DISTRO; then
			echo $DISTRO
			return 0
		fi
	done

	# Do the ubuntu/debian dance we talked about
	if dpkg-vendor --derives-from ubuntu; then
		echo $DISTRO
		return 0
	fi

	echo debian
	return 0
}

if [ "$1" = "--vendor" ]; then
	CURRENT_VENDOR="$2"
	shift 2
else
	CURRENT_VENDOR=$(getcurrent)
fi
INFO="$(readlink -f "${BASEDIR}/$CURRENT_VENDOR/apt-vendor.ent")"
VERBATIM="${BASEDIR}/../doc/apt-verbatim.ent"

if [ -z "$INFO" ] || [ ! -e "$INFO" ]; then
	echo >&2 'The current vendor is not valid or not chosen by the buildsystem yet.'
	exit 1
fi

getrawfield() {
	awk "/<!ENTITY $1/ {f=NR} f && NR-1==f { print; exit 0 }" RS='"' "${2:-$INFO}"
}

getfield() {
	local FIELD="$(getrawfield "$@")"
	FIELD="${FIELD#*>}"
	echo "${FIELD%<*}"
}

case "$1" in
debian-stable-codename|debian-oldstable-codename|debian-testing-codename|ubuntu-codename)
	getrawfield "$1" "$VERBATIM"
	;;
sourceslist-list-format|keyring-package|keyring-filename|keyring-master-filename|keyring-removed-filename|keyring-uri|current-codename)
	exec $0 --vendor $CURRENT_VENDOR 'vendor' "$@"
	;;
vendor)
	getfield "$2"
	;;
verbatim)
	getfield "$2" "$VERBATIM"
	;;
current)
	echo $CURRENT_VENDOR
	;;
*)
	echo >&2 "Unknown data field $1 requested"
	exit 2
	;;
esac