#!/bin/bash
#
# Copyright (C) 2018 Pawel Krupa (@paulfantom) - All Rights Reserved
# Permission to copy and modify is granted under the MIT license
#
# Script to automatically do a couple of things:
#   - generate a new tag according to semver (https://semver.org/)
#   - generate CHANGELOG.md by using https://github.com/skywinder/github-changelog-generator
#   - sync CHANGELOG with GitHub releases by using https://github.com/mattbrictson/chandler
#
# Tags are generated by searching for a keyword in last commit message. Keywords are:
#  - [patch] or [fix] to bump patch number
#  - [minor], [feature] or [feat] to bump minor number
#  - [major] or [breaking change] to bump major number
# All keywords MUST be surrounded with square braces.
#
# Script uses git mechanisms for locking, so it can be used in parallel builds
#
# Requirements:
#   - GH_TOKEN variable set with GitHub token. Access level: repo.public_repo
#   - docker
#   - git-semver python package (pip install git-semver)

# Exit when latest commit is tagged
[[ $(git tag --points-at) ]] && exit 0

# Some basic variables
GIT_MAIL="mail@carlosleon.info"
GIT_USER="mongrelion"
ORGANIZATION=$(echo "$TRAVIS_REPO_SLUG" | awk -F '/' '{print $1}')
PROJECT=$(echo "$TRAVIS_REPO_SLUG" | awk -F '/' '{print $2}')
GALAXY_NAME="${PROJECT#ansible-}"  # remove `ansible-` prefix
GALAXY_NAME="${GALAXY_NAME#role-}"  # remove `role-` prefix, for roles which name start with `ansible-role-`
GALAXY_URL="https://galaxy.ansible.com/${ORGANIZATION}/${GALAXY_NAME}"

# Git config
git config --global user.email "${GIT_MAIL}"
git config --global user.name "${GIT_USER}"
GIT_URL=$(git config --get remote.origin.url)
GIT_URL=${GIT_URL#*//}

# Generate TAG
GIT_TAG=none
echo "Last commit message: $TRAVIS_COMMIT_MESSAGE"
case "${TRAVIS_COMMIT_MESSAGE}" in
  *"[patch]"*|*"[fix]"* )                GIT_TAG=$(git semver --next-patch) ;;
  *"[minor]"*|*"[feat]"*|*"[feature]"* ) GIT_TAG=$(git semver --next-minor) ;;
  *"[major]"*|*"[breaking change]"* )    GIT_TAG=$(git semver --next-major) ;;
  *) echo "Keyword not detected. Doing nothing" ;;
esac
if [ "$GIT_TAG" != "none" ]; then
    echo "Assigning new tag: $GIT_TAG"
    git tag "$GIT_TAG" -a -m "Automatic tag generation for travis build no. $TRAVIS_BUILD_NUMBER"
    git push "https://${GH_TOKEN}:@${GIT_URL}" --tags || exit 0
fi

# Generate CHANGELOG.md
git checkout master
git pull
docker run -it --rm -v "$(pwd)":/usr/local/src/your-app ferrarimarco/github-changelog-generator \
               -u "${ORGANIZATION}" -p "${PROJECT}" --token "${GH_TOKEN}" \
               --release-url "${GALAXY_URL}" \
               --unreleased-label "**Next release**" --no-compare-link

git add CHANGELOG.md
git commit -m '[ci skip] Automatic changelog update'

git push "https://${GH_TOKEN}:@${GIT_URL}" || exit 0

# Sync changelog to github releases
if [ "$GIT_TAG" != "none" ]; then
    docker run -e CHANDLER_GITHUB_API_TOKEN="${GH_TOKEN}" -v "$(pwd)":/chandler -ti whizark/chandler push "${GIT_TAG}"
fi
