#!/bin/sh
set -e

#DEBHELPER#

# Prepare to move a conffile without triggering a dpkg question
prep_mv_conffile() {
	PKGNAME="$1"
	CONFFILE="$2"

	if [ -e "$CONFFILE" ]; then
		md5sum="`md5sum \"$CONFFILE\" | sed -e \"s/ .*//\"`"
		old_md5sum="`dpkg-query -W -f='${Conffiles}' $PKGNAME | sed -n -e \"\\\\' $CONFFILE'{s/ obsolete$//;s/.* //p}\"`"
		if [ "$md5sum" = "$old_md5sum" ]; then
			rm -f "$CONFFILE"
		fi
	fi
}

# Remove a no-longer used conffile
rm_conffile() {
	PKGNAME="$1"
	CONFFILE="$2"

	if [ -e "$CONFFILE" ]; then
		md5sum="`md5sum \"$CONFFILE\" | sed -e \"s/ .*//\"`"
		old_md5sum="`dpkg-query -W -f='${Conffiles}' $PKGNAME | sed -n -e \"\\\\' $CONFFILE'{s/ obsolete$//;s/.* //p}\"`"
		if [ "$md5sum" != "$old_md5sum" ]; then
			echo "Obsolete conffile $CONFFILE has been modified by you."
			echo "Saving as $CONFFILE.dpkg-bak ..."
			mv -f "$CONFFILE" "$CONFFILE".dpkg-bak
		else
			echo "Removing obsolete conffile $CONFFILE ..."
			rm -f "$CONFFILE"
		fi
	fi
}

case "$1" in
install|upgrade)
	if dpkg --compare-versions "$2" le "0.7"; then
		for c in README 50uncommitted-changes; do
			prep_mv_conffile etckeeper "/etc/etckeeper/pre-apt.d/$c"
		done
		for c in README 10git-test 30git-add 40git-rm 50git-commit; do
			prep_mv_conffile etckeeper "/etc/etckeeper/post-apt.d/$c"
		done
		for c in 40git-init 50git-ignore 50git-perm \
		         50git-pre-commit-hook 70git-add; do
			prep_mv_conffile etckeeper "/etc/etckeeper/init.d/$c"
		done
	fi
	if dpkg --compare-versions "$2" le "0.10"; then
        	for c in 10vcs-test 30git-add 30hg-addremove 40git-rm; do
			prep_mv_conffile etckeeper "/etc/etckeeper/post-install.d/$c"

		done
	fi
	if dpkg --compare-versions "$2" le "0.13"; then
        	for c in 20store-empty-directory 40rm-old-metadata; do
			rm_conffile etckeeper "/etc/etckeeper/pre-commit.d/$c"
		done
		for c in 10restore-etckeeper 20restore-metadata; do
			prep_mv_conffile etckeeper "/etc/etckeeper/init.d/$c"
		done
	fi
	if dpkg --compare-versions "$2" le "0.15"; then
        	for c in 40bzr-rm 45bzr-precommit; do
			rm_conffile etckeeper "/etc/etckeeper/commit.d/$c"
		done
	fi

	# delete files the postrm stashes away to handle purging
	rm -rf /var/cache/etckeeper/stash
esac