#!/bin/sh
#############################################################################
# Copyright (c) 2009 Novell, Inc.
# All Rights Reserved.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.   See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, contact Novell, Inc.
#
# To contact Novell about this file by physical or electronic mail,
# you may find current contact information at www.novell.com
#############################################################################
#
# Script to merge the scripts branch into another branch, e.g.
# ... hack on scripts branch ...
# git commit
# ./scripts/merge-scripts-branch SLE11_BRANCH SL110_BRANCH SL103_BRANCH ...

SUBDIRECTORY_OK=true
. "$(git --exec-path)/git-sh-setup"
require_work_tree

if test -z "$merge_scripts_branch_copy"; then
	# copy ourself out of the git working dir
	copy=$(mktemp)
	cp "$0" "$copy"
	chmod +x "$copy"
	merge_scripts_branch_copy=true exec /bin/sh -$- "$copy" "$@"
fi

usage()
{
	die "Usage: $0 [--overwrite] [-p|--pull] branch..."
}

opt_overwrite=false
opt_pull=false
while test $# -gt 0; do
	case "$1" in
	--overwrite)
		opt_overwrite=true
		shift
		;;
	-p | --pull)
		opt_pull=true
		shift
		;;
	--)
		shift
		break
		;;
	-*)
		usage
		;;
	*)
		break
		;;
	esac
done
if test $# = 0; then
	# "" means current branch
	set -- ""
fi

# remove the copy
trap 'rm -f "$0"' EXIT

cd_to_toplevel

if $opt_overwrite; then
	# temporarily set up an overwriting merge driver
	git config merge.overwrite.name "overwrite our files by theirs"
	git config merge.overwrite.driver "cp %B %A"
	mkdir -p "$GIT_DIR"/info
	echo '* merge=overwrite' >>"$GIT_DIR"/info/attributes
	trap "sed -i '/merge=overwrite/d' \"$GIT_DIR\"/info/attributes;
		rm -f $0" EXIT
fi

oldbranch=
if test -n "$*"; then
	oldbranch=$(sed -n 's|^ref: refs/heads/||p' "$GIT_DIR"/HEAD 2>/dev/null)
	if test -z "$oldbranch"; then
		oldbranch=$(git rev-parse HEAD)
	fi
fi

for branch; do
	if test "$branch" = "scripts"; then
		echo "warning: skipping branch 'scripts'" >&2
		continue
	fi
	if test -n "$branch"; then
		git checkout "$branch" || exit
	fi
	if $opt_pull; then
		git pull || exit
	fi
	git merge "scripts" || exit
done

if test -n "$oldbranch"; then
	git checkout "$oldbranch"
fi