#!/usr/bin/env bash

# Copyright 2018-present Open Networking Foundation
#
# 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.

# github-release.sh
# builds (with make) and uploads release artifacts (binaries, etc.) to github
# given a tag also create checksums files and release notes from the commit
# message

set -eu -o pipefail

# when not running under Jenkins, use current dir as workspace and a blank
# project name
WORKSPACE=${WORKSPACE:-.}
GERRIT_PROJECT=${GERRIT_PROJECT:-}

# Github organization (or user) this project is published on.  Project name should
# be the same on both Gerrit and GitHub
GITHUB_ORGANIZATION=${GITHUB_ORGANIZATION:-}

# glob pattern relative to project dir matching release artifacts
ARTIFACT_GLOB=${ARTIFACT_GLOB:-"release/*"}

# Temporary staging directory to copy artifacts to
RELEASE_TEMP="$WORKSPACE/release"

# Use "release" as the default makefile target, can be a space separated list
RELEASE_TARGETS=${RELEASE_TARGETS:-release}

# check that we're on a semver released version, or exit
pushd "$GERRIT_PROJECT"
  GIT_VERSION=$(git tag -l --points-at HEAD)

  if [[ "$GIT_VERSION" =~ ^([0-9]+)\.([0-9]+)\.([0-9]+)$ ]]
  then
    echo "git has a SemVer released version tag: '$GIT_VERSION'"
    echo "Building artifacts for GitHub release."
  else
    echo "No SemVer released version tag found, exiting..."
    exit 0
  fi
popd

# To support golang projects create a GOPATH
# If $DEST_GOPATH is not an empty string:
# - set create GOPATH, and destination directory within in
# - set PATH to include $GOPATH/bin and the system go binaries
# - symlink from $WORKSPACE/$GERRIT_PROJECT to new location in $GOPATH
# - start release from that directory

DEST_GOPATH=${DEST_GOPATH:-}
if [ ! -z "$DEST_GOPATH" ]; then
  export GOPATH=${GOPATH:-~/go}
  mkdir -p "$GOPATH/src/$DEST_GOPATH"
  export PATH=$PATH:/usr/lib/go-1.12/bin:/usr/local/go/bin:$GOPATH/bin
  release_path="$GOPATH/src/$DEST_GOPATH/$GERRIT_PROJECT"
  ln -r -s "$WORKSPACE/$GERRIT_PROJECT" "$release_path"
else
  release_path="$WORKSPACE/$GERRIT_PROJECT"
fi

if [ ! -f "$release_path/Makefile" ]; then
  echo "Makefile not found at $release_path!"
  exit 1
else
  pushd "$release_path"

  # Release description is sanitized version of the log message
  RELEASE_DESCRIPTION=$(git log -1 --pretty=%B | tr -dc "[:alnum:]\n\r\.\[\]\:\-\\\/\`\' ")

  # build the release, can be multiple space separated targets
  # shellcheck disable=SC2086
  make $RELEASE_TARGETS

  # Copy artifacts into the release temp dir
  # shellcheck disable=SC2086
  cp $ARTIFACT_GLOB "$RELEASE_TEMP"

  # create release
  gothub release \
    --user "$GITHUB_ORGANIZATION" \
    --repo "$GERRIT_PROJECT" \
    --tag  "$GIT_VERSION" \
    --name "$GERRIT_PROJECT - $GIT_VERSION" \
    --description "$RELEASE_DESCRIPTION"

  # handle release files
  pushd "$RELEASE_TEMP"

    # Generate and check checksums
    sha256sum ./* > checksum.SHA256
    sha256sum -c < checksum.SHA256

    # upload all files to the release
    for rel_file in ./*
    do
      gothub upload \
        --user "$GITHUB_ORGANIZATION" \
        --repo "$GERRIT_PROJECT" \
        --tag  "$GIT_VERSION" \
        --name "$rel_file" \
        --file "$rel_file"
    done
  popd

  popd
fi