#!/usr/bin/env bash
set -e

usage() {
    echo "usage: $0 -f <package.deb> -r <deb|deb-dev>"
    exit 1
}

check_program() {
  if ! command -v $1 &> /dev/null
  then
      echo "$1 is required and could not be found"
      exit
  fi
}

# Add a package to the local DEB repository
#
# $1: path of the repository.
# $2: suite (eg. "stable")
# $3: path of the DEB file.
add_deb() {
    cp -f $3 $1/$2
    pushd $1/$2 > /dev/null
    rm -f $(basename -- $3).asc
    gpg --detach-sign --digest-algo SHA256 --armor $(basename -- $3)
    popd > /dev/null
}

# Update the local DEB repository
#
# $1: path of the repository
# $2: suite (eg. "stable")
update_repo() {
    # fixme(leogr): we cannot use apt-ftparchive --arch packages ...
    # since our .deb files ends with "_x86_64" instead of "amd64".
    # See https://manpages.debian.org/jessie/apt-utils/apt-ftparchive.1.en.html
    #
    # As a workaround, we temporarily stick here with "amd64" 
    # (the only supported arch at the moment)
    local arch=amd64

    local component=main
    local debs_dir=$2
    local release_dir=dists/$2
    local packages_dir=${release_dir}/${component}/binary-${arch}

    pushd $1 > /dev/null

    # packages metadata
    apt-ftparchive packages ${debs_dir} > ${packages_dir}/Packages
    gzip -c ${packages_dir}/Packages > ${packages_dir}/Packages.gz
    bzip2 -z -c ${packages_dir}/Packages > ${packages_dir}/Packages.bz2
    
    # release metadata
    apt-ftparchive release \
      -o APT::FTPArchive::Release::Origin=Falco \
      -o APT::FTPArchive::Release::Label=Falco \
      -o APT::FTPArchive::Release::Suite=$2 \
      -o APT::FTPArchive::Release::Codename=$2 \
      -o APT::FTPArchive::Release::Components=${component} \
      -o APT::FTPArchive::Release::Architectures=${arch} \
      ${release_dir} > ${release_dir}/Release

    # release signature
    gpg --detach-sign --digest-algo SHA256 --armor ${release_dir}/Release
    rm -f ${release_dir}/Release.gpg
    mv ${release_dir}/Release.asc ${release_dir}/Release.gpg

    popd > /dev/null
}

# parse options
while getopts ":f::r:" opt; do
    case "${opt}" in
        f )
          file=${OPTARG}
          ;;
        r )
          repo="${OPTARG}"
          [[ "${repo}" == "deb" || "${repo}" == "deb-dev" ]] || usage
          ;;
        : )
          echo "invalid option: ${OPTARG} requires an argument" 1>&2
          exit 1
          ;;
        \?)
          echo "invalid option: ${OPTARG}" 1>&2
          exit 1
          ;;
    esac
done
shift $((OPTIND-1))

# check options
if [ -z "${file}" ] || [ -z "${repo}" ]; then
    usage
fi

# check prerequisites
check_program apt-ftparchive
check_program gzip
check_program bzip2
check_program gpg
check_program aws

# settings
debSuite=stable
s3_bucket_repo="s3://falco-distribution/packages/${repo}"
cloudfront_path="/packages/${repo}"
tmp_repo_path=/tmp/falco-$repo

# prepare repository local copy
echo "Fetching ${s3_bucket_repo}..."
mkdir -p ${tmp_repo_path}
aws s3 cp ${s3_bucket_repo} ${tmp_repo_path} --recursive

# update the repo
echo "Adding ${file}..."
add_deb ${tmp_repo_path} ${debSuite} ${file}
update_repo ${tmp_repo_path} ${debSuite}

# publish
package=$(basename -- ${file})
echo "Publishing ${package} to ${s3_bucket_repo}..."
aws s3 cp ${tmp_repo_path}/${debSuite}/${package} ${s3_bucket_repo}/${debSuite}/${package} --acl public-read
aws s3 cp ${tmp_repo_path}/${debSuite}/${package}.asc ${s3_bucket_repo}/${debSuite}/${package}.asc --acl public-read
aws s3 sync ${tmp_repo_path}/dists ${s3_bucket_repo}/dists --delete --acl public-read

aws cloudfront create-invalidation --distribution-id ${AWS_CLOUDFRONT_DIST_ID} --paths ${cloudfront_path}/${debSuite}/${package}
aws cloudfront create-invalidation --distribution-id ${AWS_CLOUDFRONT_DIST_ID} --paths ${cloudfront_path}/${debSuite}/${package}.asc
aws cloudfront create-invalidation --distribution-id ${AWS_CLOUDFRONT_DIST_ID} --paths ${cloudfront_path}/dists/*