#!/bin/bash
set -euo pipefail

curl -sL https://raw.githubusercontent.com/Luzifer/github-publish/master/SHA256SUMS | \
  grep "golang.sh" | sha256sum -c || exit 2

( which zip 2>&1 1>/dev/null ) || {
  ( which apk 2>&1 1>/dev/null ) && apk add --update zip
  ( which apt-get 2>&1 1>/dev/null ) && apt-get install -y zip
}

function step {
  echo "===> $@..."
}

VERSION=$(git describe --tags --exact-match || echo "ghpublish__notags")
PWD=$(pwd)
godir=${PWD/${GOPATH}\/src\/}
REPO=${REPO:-$(echo ${godir} | cut -d '/' -f 3)}
GHUSER=${GHUSER:-$(echo ${godir} | cut -d '/' -f 2)}
ARCHS=${ARCHS:-"linux/amd64 linux/arm darwin/amd64 windows/amd64"}
DEPLOYMENT_TAG=${DEPLOYMENT_TAG:-${VERSION}}
PACKAGES=${PACKAGES:-$(echo ${godir} | cut -d '/' -f 1-3)}
BUILD_DIR=${BUILD_DIR:-.build}

step Retrieve dependencies
go get github.com/aktau/github-release
go get github.com/mitchellh/gox

step Test code
go vet ${PACKAGES}
go test ${PACKAGES}

step Compile program
mkdir ${BUILD_DIR}
gox -ldflags="-X main.version=${VERSION}" -osarch="${ARCHS}" \
  -output="${BUILD_DIR}/{{.Dir}}_{{.OS}}_{{.Arch}}"\
  ${PACKAGES}

step Generate binary SHASUMs
cd ${BUILD_DIR}
sha256sum * > SHA256SUMS

step Packing archives
for file in *; do
  if [ "${file}" = "SHA256SUMS" ]; then
    continue
  fi

  if [[ ${file} == *linux* ]]; then
    tar -czf "${file%%.*}.tar.gz" "${file}"
  else
    zip "${file%%.*}.zip" "${file}"
  fi

  rm "${file}"
done

step Generate archive SHASUMs
sha256sum * >> SHA256SUMS
grep -v 'SHA256SUMS' SHA256SUMS > SHA256SUMS.tmp
mv SHA256SUMS.tmp SHA256SUMS

step Publish builds to Github

if ( test "${VERSION}" == "ghpublish__notags" ); then
  echo "No tag present, stopping build now."
  exit 0
fi

if [ -z "${GITHUB_TOKEN}" ]; then
  echo "Please set \$GITHUB_TOKEN environment variable"
  exit 1
fi

step Create a drafted release
github-release release --user ${GHUSER} --repo ${REPO} --tag ${DEPLOYMENT_TAG} --name ${DEPLOYMENT_TAG} --draft || true

step Upload build assets
for file in * SHA256SUMS; do
  echo "- ${file}"
  github-release upload --user ${GHUSER} --repo ${REPO} --tag ${DEPLOYMENT_TAG} --name ${file} --file ${file}
done

echo -e "\n\n=== Recorded checksums ==="
cat SHA256SUMS

step Cleanup build directory
cd -
rm -rf ${BUILD_DIR}