#!/bin/bash
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
#
# This script is used to create a release candidate. It will update the current
# .auroraversion as well as creates a tag for the new release candidate and
# publishes the source distribution and signatures to be voted on.
#
#   master~1 (0.5.0-snapshot) ----- master (0.6.0-snapshot)
#                             \---- 0.5.0 (0.5.0)
#
# A email template will be generated after successfully generating a release
# candidate which will need to be sent to the dev@ and private@ mailing lists.
#
set -o errexit
set -o nounset

# If GPG_TTY is unset, set it to the default tty. Otherwise git will not prompt
# for a passpharse for the GPG-key and silently fail when tryint to create signed
# commits/tags.
export GPG_TTY=${GPG_TTY:-$(tty)}

rc_number=0
override_version=''
aurora_git_web_url='https://gitbox.apache.org/repos/asf?p=aurora.git'
aurora_svn_dist_url='https://dist.apache.org/repos/dist/dev/aurora'

function print_help_and_exit {
cat <<EOF
Apache Aurora release candidate tool.

Usage: $0 [-h] [-l p|m|M] [-r #] [-p | publish]

  -h  Print this help message and exit
  -l  Increment level, must be one of:
        p, patch (default)
        m, minor
        M, major
  -v  Override the existing version in .auroraversion
  -r  Release candidate number (default: 0)
  -p  Publish the release candidate (default: dry-run, does not publish anything)
EOF
exit 0
}

publish=0
increment_level="patch"
rc_number=0
while getopts ":hl:v:r:p" opt; do
  case $opt in
    l)
      case ${OPTARG} in
        'p' | 'patch') increment_level='patch' ;;
        'm' | 'minor') increment_level='minor' ;;
        'M' | 'major') increment_level='major' ;;
         *) echo 'Unknown increment level'; exit 1 ;;
      esac
      ;;
    r)
      rc_number=${OPTARG}
      ;;
    p)
      publish=1
      ;;
    h)
      print_help_and_exit
      ;;
    v)
      override_version=${OPTARG}
      ;;
    *  )
      echo "Unknown option: -$OPTARG"
      print_help_and_exit
      ;;
  esac
done

shift $(($OPTIND - 1))
if [[ "${1:-dry-run}" == "publish" ]]; then
  publish=1
fi

# Update local repository
git fetch --all -q
git fetch --tags -q

starting_git_branch=$(git rev-parse --abbrev-ref HEAD)

# Verify that this is a clean repository
if [[ -n "`git status --porcelain`" ]]; then
  echo "ERROR: Please run from a clean git repository."
  exit 1
# A patch release may be performed from the patched git SHA, but all other releases
# should be from master.
elif [[ "$starting_git_branch" != "master" && "$increment_level" != 'patch' ]]; then
  echo "ERROR: This script must be run from master when not creating a patch release"
  exit 1
fi

if [[ ! -f .auroraversion ]]; then
  echo "Warrning: This script must be run from the root of the repository"
  exit 1
fi

# Calculate the new version string
current_version=$(cat .auroraversion | tr '[a-z]' '[A-Z]')
# When patching a release, we may be cherry-picking on the released git tag,
# which would not contain a -SNAPSHOT version identifier.  Other releases,
# however, should start from a git tree with a -SNAPSHOT version.
if ! [[ $current_version =~ .*-SNAPSHOT || "$increment_level" == 'patch' ]]; then
  echo "ERROR: .auroraversion is required to contain 'SNAPSHOT', it is ${current_version}"
  exit 1
else
  if [[ $override_version != "" ]]; then
    current_version=$override_version
  fi

  major=`echo $current_version | cut -d. -f1`
  minor=`echo $current_version | cut -d. -f2`
  patch=`echo $current_version | cut -d. -f3 | cut -d- -f1`

  current_version="${major}.${minor}.${patch}"

  if [[ $increment_level == "patch" ]]; then
    new_master_version="${major}.${minor}.$((patch + 1))"
  elif [[ $increment_level == "minor" ]]; then
    new_master_version="${major}.$((minor + 1)).0"
  elif [[ $increment_level == "major" ]]; then
    new_master_version="$((major + 1)).0.0"
  else
    echo "Unknown release increment ${increment_level}"
    exit 1
  fi

  new_snapshot_version="${new_master_version}-SNAPSHOT"
fi

if [[ "$increment_level" == 'patch' && "$starting_git_branch" != 'master' ]]; then
  echo 'NOTE: This release candidate is patching a non-master branch.'
  echo '.auroraversion will be treated as the patched release, rather'
  echo 'than the to-be-released version.'
  current_version="$new_master_version"
fi

# Add the rc tag to the current version
rc_version="${current_version}-rc${rc_number}"
rc_version_tag="rel/${rc_version}"

echo
echo "Generating release candidate ${rc_version}"
echo

# Make sure the tag does not exist
if git rev-parse ${rc_version_tag} >/dev/null 2>&1; then
  echo "ERROR: tag ${rc_version_tag} exists."
  exit 1
fi

# Reset instructions
current_git_rev=$(git rev-parse HEAD)
function print_reset_instructions {
cat <<EOF
To roll back your local repo you will need to run:

  git checkout "$starting_git_branch"
  git reset --hard ${current_git_rev}
  git branch -D "stage_${rc_version_tag}"
  git tag -d ${rc_version_tag}
EOF
}

# If anything goes wrong from here then print roll back instructions before exiting.
function print_rollback_instructions {
  echo "ERROR: Looks like something has failed while creating the release candidate."
  print_reset_instructions
}
trap print_rollback_instructions EXIT

# All check are now complete, before we start alert if we are in dry-run
if [[ $publish == 0 ]]; then
  echo "Performing dry-run, run with '-p' when you are ready to run and publish a release candidate"
fi

# This should be a clean repo we are working against. Run clean just to ensure it is.
git clean -fdxq

echo "Generating changelog"
./build-support/release/changelog $current_version
git add CHANGELOG
git commit -m "Updating CHANGELOG for ${current_version} release."

echo "Committing updated .auroraversion on master"
echo $new_snapshot_version > .auroraversion
git add .auroraversion
git commit -m "Incrementing snapshot version to ${new_snapshot_version}."

echo "Creating ${rc_version} staging branch"
git checkout -b "stage_${rc_version_tag}"

echo "Updating .auroraversion on staging branch"
# Increment the version and create a branch
echo ${rc_version} > .auroraversion
git add .auroraversion
git commit -m "Updating .auroraversion to ${rc_version}."

# Build the source distribution from the new branch
echo "Building the source distribution"
dist_dir=dist
dist_name="apache-aurora-${rc_version}"

mkdir -p ${dist_dir}
git archive --prefix=${dist_name}/ -o ${dist_dir}/${dist_name}.tar.gz HEAD
pushd ${dist_dir}
  # Sign the tarball.
  echo "Signing the distribution"
  gpg --armor --output ${dist_name}.tar.gz.asc --detach-sig ${dist_name}.tar.gz

  # Create the checksum
  echo "Creating checksum"
  shasum -a 512 ${dist_name}.tar.gz > ${dist_name}.tar.gz.sha512
popd

aurora_svn_rc_url="${aurora_svn_dist_url}/${rc_version}"

# Publish release candidate to svn and commit and push the new git tag
if [[ $publish == 1 ]]; then
  echo "Publishing release candidate to ${aurora_svn_rc_url}"
  svn mkdir ${aurora_svn_rc_url} -m "aurora-${current_version} release candidate ${rc_version_tag}"
  svn co --depth=empty ${aurora_svn_rc_url} ${dist_dir}
  pushd ${dist_dir}
  svn add ${dist_name}*
  svn ci -m "aurora-${current_version} release candidate ${rc_version_tag}"
  popd

  echo "Creating tag ${rc_version_tag}"
  git tag -s ${rc_version_tag} \
    -m "Apache Aurora ${current_version} release candidate ${rc_version_tag}"
  git push origin "${rc_version_tag}"

  if [[ "$starting_git_branch" = "master" ]]; then
    echo "Pushing updated .auroraversion to master"
    git checkout master
    git push origin master
  else
    echo 'This is a patch release not starting from master, so an updated .auroraversion'
    echo 'will not be pushed to master.'
  fi
fi

echo "Done creating the release candidate. The following draft email has been created"
echo "to send to the dev@aurora.apache.org mailing list"
echo

# Create the email template for the release candidate to be sent to the mailing lists.
if [[ $(uname) == Darwin ]]; then
  vote_end=$(date -v+3d)
else
  vote_end=$(date -d+3days)
fi

MESSAGE=$(cat <<__EOF__
To: dev@aurora.apache.org
Subject: [VOTE] Release Apache Aurora ${current_version} RC${rc_number}

All,

I propose that we accept the following release candidate as the official
Apache Aurora ${current_version} release.

Aurora ${rc_version} includes the following:
---
The RELEASE NOTES for the release are available at:
${aurora_git_web_url}&f=RELEASE-NOTES.md&hb=${rc_version_tag}

The CHANGELOG for the release is available at:
${aurora_git_web_url}&f=CHANGELOG&hb=${rc_version_tag}

The tag used to create the release candidate is:
${aurora_git_web_url};a=shortlog;h=refs/tags/${rc_version_tag}

The release candidate is available at:
${aurora_svn_rc_url}/${dist_name}.tar.gz

The SHA-512 checksum of the release candidate can be found at:
${aurora_svn_rc_url}/${dist_name}.tar.gz.sha512

The signature of the release candidate can be found at:
${aurora_svn_rc_url}/${dist_name}.tar.gz.asc

The GPG key used to sign the release are available at:
${aurora_svn_dist_url}/KEYS

Please download, verify, and test.

The vote will close on ${vote_end}

[ ] +1 Release this as Apache Aurora ${current_version}
[ ] +0
[ ] -1 Do not release this as Apache Aurora ${current_version} because...

__EOF__
)

echo "--------------------------------------------------------------------------------"
echo
echo "${MESSAGE}"
echo
echo "--------------------------------------------------------------------------------"
echo

# Print reset instructions if this was a dry-run
if [[ $publish == 0 ]]; then
  echo
  echo "This was a dry run, nothing has been published."
  echo
  print_reset_instructions
fi

# Unset error message handler and exit
trap '' EXIT
exit 0