#!/usr/bin/env bash
set -euo pipefail

: "${RUNNER_S3_BUCKET:=las-github-runner-dal}"
: "${RUNNER_S3_ENDPOINT:=s3.us-north-1.qiniucs.com}"
: "${RUNNER_S3_REGION:=us-north-1}"
: "${RUNNER_S3_PREFIX:=ci-cache/${GITHUB_REPOSITORY:?GITHUB_REPOSITORY is required}}"

raw_job_name="${GITHUB_JOB:-unknown-job}"
RUNNER_S3_JOB_SCOPE="$(printf '%s' "${raw_job_name}" | sed 's/[^[:alnum:]._-]/-/g')"
export RUNNER_S3_JOB_SCOPE

RUNNER_S3_RCLONE_CONFIG=""

s3_cache_enabled() {
  [[ -n "${RUNNER_S3_AK:-}" && -n "${RUNNER_S3_SK:-}" ]] && command -v rclone >/dev/null 2>&1
}

s3_cache_configure_rclone() {
  if [[ -n "${RUNNER_S3_RCLONE_CONFIG}" ]]; then
    return 0
  fi

  local endpoint="${RUNNER_S3_ENDPOINT}"

  if [[ ! "${endpoint}" =~ ^https?:// ]]; then
    endpoint="https://${endpoint}"
  fi

  RUNNER_S3_RCLONE_CONFIG="$(mktemp)"
  chmod 600 "${RUNNER_S3_RCLONE_CONFIG}"
  cat > "${RUNNER_S3_RCLONE_CONFIG}" <<CONFIG
[cis3]
type = s3
provider = Qiniu
access_key_id = ${RUNNER_S3_AK}
secret_access_key = ${RUNNER_S3_SK}
region = ${RUNNER_S3_REGION}
endpoint = ${endpoint}
force_path_style = false
no_check_bucket = true
CONFIG
  export RUNNER_S3_RCLONE_CONFIG
}

s3_cache_remote_path() {
  printf 'cis3:%s/%s' "${RUNNER_S3_BUCKET}" "${1#/}"
}

s3_cache_rclone() {
  s3_cache_configure_rclone
  rclone --config "${RUNNER_S3_RCLONE_CONFIG}" --stats=0 --retries "${RUNNER_S3_RCLONE_RETRIES:-4}" "$@"
}

s3_cache_get() {
  local output_path="$2"

  rm -f "${output_path}"
  s3_cache_rclone copyto "$(s3_cache_remote_path "$1")" "${output_path}"
  [[ -s "${output_path}" ]]
}

s3_cache_put() {
  s3_cache_rclone copyto "$2" "$(s3_cache_remote_path "$1")"
}

s3_cache_upload_if_changed() {
  local object_key="$1"
  local archive_path="$2"
  local tmp_dir
  local hash_path
  local remote_hash_path
  local local_hash
  local remote_hash

  tmp_dir="$(mktemp -d)"
  hash_path="${tmp_dir}/local.sha256"
  remote_hash_path="${tmp_dir}/remote.sha256"
  local_hash="$(sha256sum "${archive_path}" | awk '{print $1}')"
  printf '%s\n' "${local_hash}" > "${hash_path}"

  if s3_cache_get "${object_key}.sha256" "${remote_hash_path}"; then
    remote_hash="$(tr -d '[:space:]' < "${remote_hash_path}")"
    if [[ "${remote_hash}" == "${local_hash}" ]]; then
      echo "S3 cache unchanged: ${object_key}"
      rm -rf "${tmp_dir}"
      return 0
    fi
    echo "S3 cache changed: ${object_key} remote_sha256=${remote_hash} local_sha256=${local_hash}"
  else
    echo "No existing S3 cache hash for ${object_key}; uploading"
  fi

  s3_cache_put "${object_key}" "${archive_path}"
  s3_cache_put "${object_key}.sha256" "${hash_path}"
  echo "Uploaded S3 cache: ${object_key} sha256=${local_hash}"
  rm -rf "${tmp_dir}"
}

s3_cache_upload_if_missing() {
  local object_key="$1"
  local archive_path="$2"

  echo "Uploading S3 cache if missing: ${object_key}"
  s3_cache_rclone copyto --ignore-existing "${archive_path}" "$(s3_cache_remote_path "${object_key}")"
}