#!/bin/bash
# Update release notes and tag a release
#
#  Copyright (C) 2014-2023 Ryan Specialty, LLC.
#
#  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/>.

set -euo pipefail

declare -r RELEASE_FILE="${RELEASE_FILE:-RELEASES.md}"


assert-valid-tag()
{
  local -r tag="${1?Missing tag}"

  # Note that '$' is intentionally omitted to permit suffixes
  if [[ ! "$tag" =~ ^v[0-9]+\.[0-9]+\.[0-9]+ ]]; then
    echo "error: tag '$tag' must be of the form 'vM.m.r'" >&2
    return 1
  fi

  # Compare with the most recent tag and make sure this is greater
  local -r prev=$(git describe --abbrev=0)
  local -r gt=$(echo -e "$tag\n$prev" | sort -V | tail -n1)

  test "$tag" == "$gt" || {
    echo "error: tag '$tag' is not greater than previous tag '$prev'" >&2
    return 1
  }
}


extract-next()
{
  local -r file="${1?Missing file}"

  awk '
    /^NEXT$/ { out = 1; getline; next }
    /^====/ && out { nextfile }
    out { print }
    ' "$file" \
      | head -n-1
}


main()
{
  local tag="${1?Missing new tag name}"

  assert-valid-tag "$tag" || return

  # We don't want to tag anything bad!
  make check || return

  local -r notes=$(extract-next "$RELEASE_FILE")

  test -n "$notes" || {
    echo "error: missing NEXT heading in $RELEASE_FILE" >&2
    return 1
  }

  local -r date=$(date +%Y-%m-%d)
  local -r heading="$tag ($date)"
  local -r hline="${heading//?/=}"

  echo
  echo "$heading"
  echo "$hline"
  echo "$notes"

  echo
  read -p "Accept above release notes and tag $tag? (y/N): "
  if [[ ! "$REPLY" =~ ^y(es?)? ]]; then
    echo "error: aborted by user" >&2
    return 2
  fi

  # Note that this also runs the release-check after tagging to ensure that
  # we've addressed all issues that would cause the CI job to blow up.
  set -x
  sed -i "/^NEXT\$/ {
      s|^NEXT$|$heading\n$hline|
      n;d
    }" "$RELEASE_FILE" \
    && git add "$RELEASE_FILE" \
    && git commit -m "RELEASES.md: Update for $tag" \
    && git tag "$tag" -m "$notes" \
    && build-aux/release-check
  set +x

  echo
  echo "Please review the above and then push your changes."
  echo
  echo "To reverse these actions, run:"
  echo "  \$ git reset HEAD^"
  echo "  \$ git checkout $RELEASE_FILE"
  echo "  \$ git tag -d $tag"
}


main "$@" || {
  set +x
  code=$?
  echo "release failed" >&2
  exit $code
}