#!/bin/sh
# In a git/autoconf/automake-enabled project with a NEWS file and a version-
# controlled .prev-version file, automate the procedure by which we record
# the date, release-type and version string in the NEWS file.  That commit
# will serve to identify the release, so apply a signed tag to it as well.
VERSION=2009-11-06.10 # UTC

# Note: this is a bash script (could be zsh or dash)

# Copyright (C) 2009 Free Software Foundation, Inc.

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# 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, see <http://www.gnu.org/licenses/>.

# Written by Jim Meyering

ME=`basename "$0"`
warn() { printf '%s: %s\n' "$ME" "$*" >&2; }
die() { warn "$*"; exit 1; }

help_version()
{
  case $1 in
    --help) cat <<EOF
Usage: $ME VERSION RELEASE_TYPE

Run this script to perform the final pre-release NEWS update
in which the date, release-type and version string are recorded.
Commit that result with a log entry marking the release, and apply
a signed tag.  Run it from your project's the top-level directory.

Requirements:
- you use git for version-control
- a NEWS file, with line 3 identical to this:
* Noteworthy changes in release ?.? (????-??-??) [?]
- a version-controlled .prev-version file

Options:
  --help     print this help, then exit
  --version  print version number, then exit

EXAMPLE:
To update NEWS and tag the beta 8.1 release of coreutils, I would run this:

  $ME 8.1 beta

Report bugs and patches to <bug-gnulib@gnu.org>.
EOF
      exit ;;

    --version)
      year=`echo "$VERSION" | sed 's/[^0-9].*//'`
      cat <<EOF
$ME $VERSION
Copyright (C) $year Free Software Foundation, Inc,
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
EOF
      exit ;;

  *) die "unrecognized option: $1";;
  esac
}

case $# in
  1) help_version $1; exit 0;;
  2) ;;
  *) warn "Usage: $ME VERSION TYPE"; exit 1;;
esac

ver=$1
type=$2

# Verify that $ver looks like a version number, and...
echo "$ver"|grep -E '^[0-9][0-9.]*[0-9]$' > /dev/null \
  || die "invalid version: $ver"
prev_ver=$(cat .prev-version) \
  || die 'failed to determine previous version number from .prev-version'

# Verify that $ver is sensible (> .prev-version).
case $(printf "$prev_ver\n$ver\n"|sort -V -u|tr '\n' ':') in
  "$prev_ver:$ver:") ;;
  *) die "invalid version: $ver";;
esac

case $type in
  alpha|beta|stable) ;;
  *) die "invalid release type: $type";;
esac

# Extract package name from Makefile.
pkg=$(sed -n 's/^PACKAGE = \(.*\)/\1/p' Makefile) \
  || die 'failed to determine package name from Makefile'

# simple check: no question marks on line 3 of NEWS
noteworthy='* Noteworthy changes in release'
test "$(sed -n 3p NEWS)" = "$noteworthy ?.? (????-??-??) [?]" \
  || die 'line 3 of NEWS looks fishy!'

# No dirt allowed.
case $(git diff-index --name-only HEAD) in
  '') ;;
  *) die 'this tree is dirty; commit your changes first';;
esac

# update NEWS to have today's date, plus desired version number and $type
perl -MPOSIX -ni -e 'my $today = strftime "%F", localtime time;' \
 -e 'my ($type, $ver) = qw('"$type $ver"');' \
 -e 'my $pfx = "'"$noteworthy"'";' \
 -e 'print $.==3 ? "$pfx $ver ($today) [$type]\n" : $_' \
     NEWS || die 'failed to update NEWS'

# Ensure the current branch name is "master":
curr_br=$(git rev-parse --symbolic-full-name HEAD)
test "$curr_br" = refs/heads/master || die not on master

printf "version $ver\n\n* NEWS: Record release date.\n" \
    | git commit -F -  -a || die 'git commit failed'
git tag -s -m "$pkg $ver" v$ver HEAD || die 'git tag failed'

# Local variables:
# indent-tabs-mode: nil
# eval: (add-hook 'write-file-hooks 'time-stamp)
# time-stamp-start: "VERSION="
# time-stamp-format: "%:y-%02m-%02d.%02H"
# time-stamp-time-zone: "UTC"
# time-stamp-end: " # UTC"
# End: