#!/bin/sh
#
# mfh - Merge from head to a given branch
# Copyright 2013 Baptiste Daroussin
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# MAINTAINER=	portmgr@FreeBSD.org

set -e

err() {
	echo $@ >&2
	exit 1
}

clean() {
	rm -rf ${dir}
	exit 1
}

ask() {
	question=${1}

	answer=x
	while [ "${answer}" != "y" -a "${answer}" != "n" ] ; do
		read -p "${question} [yn] " answer
	done

	[ "${answer}" = "y" ] && return 0
	return 1
}

[ $# -ne 2 ] && err "Takes 2 arguments: <branch> <revnumber>"
branch=$1
rev=${2##r} # remove a leading "r"
case ${rev} in
''|*[!0-9]*) err "revision should be a number" ;;
esac

svnserver="svn.FreeBSD.org"

if [ -n "$(type svn 2>/dev/null)" ]; then
	svn=svn
elif [ -n "$(type svnlite 2>/dev/null)" ]; then
	svn=svnlite
else
	err "svn(1) and svnlite(1) not found. please install devel/subversion"
fi


dir=$(mktemp -d /tmp/merge.XXX)
cd ${dir}
${svn} co --depth=empty svn+ssh://${svnserver}/ports/branches/${branch}
filelist=""
# svn:// is faster than svn+ssh://. Use it wherever it's possible.
for f in $(${svn} diff --summarize -c ${rev} svn://${svnserver}/ports/head); do
	case ${f} in
	*/*) ;;
	*)continue;;
	esac
	f=${f#*/ports/head/}
	f=${f%/*}
	filelist="${filelist}\n${f}"
done
filelist=$(echo -e ${filelist} | sort -u)
echo "MFH: r${rev}" > commit.txt
${svn} log -r${rev} svn://${svnserver}/ports/head | sed '1,2d;$d;/^MFH:/d' >> commit.txt
for f in ${filelist}; do
	${svn} up --parents ${branch}/${f}
done
${svn} up --quiet ${branch}
${svn} merge -c r${rev} ^/head/ ${branch}
${svn} up --quiet ${branch}
${svn} diff ${branch}
ask "Do you want to commit?" || clean
${EDITOR:-vi} commit.txt
${svn} ci -F commit.txt ${branch}
rm -rf ${dir}