#!/bin/bash
# Copyright 2021 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.


readonly current_dir="$(dirname "$(realpath -e "${BASH_SOURCE[0]}")")"

readonly chroot_default="${current_dir}/../../../../../chroot"

validate () {
  # @FUNCTION: validate
  # @USAGE: validates inputs to build_*
  # @DESCRIPTION:
  #
  # Args:
  #   $1:  Server name (as built/installed into /usr/bin on the chroot)
  #   $2:  Dockerfile path for the build
  #   $3:  (optional) chroot path
  #   $4:  (optional) tags
  #   $5:  (optional) output file for metadata
  #   $6:  (optional) host
  #   $7:  (optional) project
  #   $8+: (optional) labels
  server_name=""
  docker_file=""
  chroot_arg=""
  tags=""
  output_path=""
  registry_name=""
  cloud_project=""
  while [[ $# -gt 0 ]]; do
    case $1 in
      --service| -s)
        server_name="$2"
        shift 2
        ;;
      --docker_file| -d)
        docker_file="$2"
        shift 2
        ;;
      --chroot| -c)
        chroot_arg="$2"
        shift 2
        ;;
      --tags| -t)
        tags="$2"
        shift 2
        ;;
      --output| -o)
        output_path="$2"
        shift 2
        ;;
      --host| -h)
        registry_name="$2"
        shift 2
        ;;
      --project| -p)
        cloud_project="$2"
        shift 2
        ;;
      *)
        break
        ;;
    esac
  done

  if [[ "${server_name}" == "" || "${docker_file}" == "" ]]; then
    die "${FUNCNAME[0]}: Server name and Dockerfile path required"
  fi
  # Aggregate rest of CLI arguments as labels into an array
  labels=( "$@" )

  # shellcheck source=/dev/null
  if [[ -e ${CHROOT_VERSION_FILE} ]]; then
    echo "Script must run outside the chroot since this depends on docker"
    exit 1
  fi

  chroot="${chroot_arg}"
  if [ -z "${chroot}" ]; then
    echo "No chroot specified, so defaulting to: ${chroot_default}"
    chroot="${chroot_default}"
  fi

  if [ ! -d "${chroot}" ]; then
    echo "chroot path does not exist: ${chroot}"
    exit 1
  fi

  readonly default_tag="local-${USER}"
  if [[ "${tags}" == "" ]]; then
    echo "No tags specified, defaulting to: ${default_tag}"
    tags="${default_tag}"
  fi

  readonly default_registry_name="us-docker.pkg.dev"
  if [[ "${registry_name}" == "" ]]; then
    echo "No host specified, defaulting to: ${default_registry_name}"
    registry_name="${default_registry_name}"
  fi

  readonly default_cloud_project="cros-registry/test-services"
  if [[ "${cloud_project}" == "" ]]; then
    echo "No project specified, defaulting to: ${default_cloud_project}"
    cloud_project="${default_cloud_project}"
  fi

  readonly image_name="${server_name}"
  readonly image_path="${registry_name}/${cloud_project}/${image_name}"

  readonly server_name docker_file chroot_arg tags
}

ensure_gcloud_helpers() {
  # @FUNCTION: ensure_gcloud_helpers
  # @USAGE: ensure_gcloud_helpers
  # @DESCRIPTION:
  #   Setup gcloud credential helpers for Google Cloud container registries.

  # First call sets up default GCR registries, second call sets up
  # Artifact Registry registries.
  gcloud --quiet --verbosity=error auth configure-docker
  gcloud --quiet --verbosity=error auth configure-docker us-docker.pkg.dev
}

build_image() {
  # @FUNCTION: build_image
  # @USAGE: Docker builds + uploads to the registry.
  # @DESCRIPTION:

  # Construct and execute build command
  args=(-f "${docker_file}")

  # Map tags into -t options
  ntag=0
  IFS=,
  for tag in ${tags}; do
      ntag="$((ntag+1))"
      args+=(-t "${image_path}:${tag}")
  done

  # Map labels into --label options
  for label in "${labels[@]}"; do
      args+=(--label "${label:Q}")
  done
  args+=("${build_context}")

  echo docker build "${args[@]}"
  docker build "${args[@]}"

  # Print debugging info
  ensure_gcloud_helpers
  echo
  echo "== Gcloud helper configuration"
  docker-credential-gcloud list

  echo
  echo "== User Authorization Scopes"
  curl -H "Authorization: Bearer $(gcloud auth print-access-token)" \
       https://www.googleapis.com/oauth2/v1/tokeninfo

  # Push image to registry
  docker push --all-tags "${image_path}"

  # write output if requested
  if [[ -n "${output_path}" ]]; then
    local digest
    digest=$(docker inspect --format='{{index .RepoDigests 0}}' "${image_path}:${tag[0]}" | cut -d@ -f2)

    cat <<EOF > "${output_path}"
{
    "repository" : {
       "hostname": "${registry_name}",
       "project" : "${cloud_project}"
    },
    "name" : "${image_name}",
    "digest" : "${digest}",
    "tags" : [
EOF

    ii=0
    local tag_block=""
    IFS=,
    for tag in ${tags}; do
        tag_block+="      \"${tag}\""

        ii="$((ii+1))"
        if [[ $ii -lt ${ntag} ]]; then
          tag_block+=",\n"
        fi
    done
    echo -e "${tag_block}" >> "${output_path}"

    cat <<EOF >> "${output_path}"
    ]
}
EOF
  fi
}


build_container_image(){
  # @FUNCTION: build_container_image
  # @USAGE: [server_name]
  # @DESCRIPTION:
  #
  # Args:
  #   $1:  Server name (as built/installed into /usr/bin on the chroot)
  #   $2:  Dockerfile path for the build
  #   $3:  (optional) chroot path
  #   $4:  (optional) tags
  #   $5:  (optional) output file for metadata
  #   $6:  (optional) host
  #   $7:  (optional) project
  #   $8+: (optional) labels

  validate "$@"
  readonly build_context=$(dirname "${docker_file}")
  build_image
  trap 'rm -rf "${build_context}"' EXIT
}


build_server_image() {
  # @FUNCTION: build_server_image
  # @USAGE: [server_name]
  # @DESCRIPTION:
  #
  # Args:
  #   $1: Server name (as built/installed into /usr/bin on the chroot)
  #   $2:  Dockerfile path for the build
  #   $3:  (optional) chroot path
  #   $4:  (optional) tags
  #   $5:  (optional) output file for metadata
  #   $6:  (optional) host
  #   $7:  (optional) project
  #   $8+: (optional) labels
  validate "$@"

  readonly tmpdir=$(mktemp -d)
  trap 'rm -rf "${tmpdir}"' EXIT
  cp "${chroot}/usr/bin/${server_name}" "${tmpdir}"

  readonly build_context="${tmpdir}"
  build_image
}