#!/usr/bin/env bash

set -euo pipefail

SCRIPT_DIR=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)
ROOT_DIR=$(cd -- "${SCRIPT_DIR}/.." && pwd)
CONFIG_FILE="${ROOT_DIR}/config/mesa-opt.conf"
DIST_DIR="${ROOT_DIR}/dist"
APT_DIR="${DIST_DIR}/aptrepo"
DIST_ENV="${DIST_DIR}/package-info.env"

if [[ -f "${CONFIG_FILE}" ]]; then
  # shellcheck disable=SC1090
  source "${CONFIG_FILE}"
fi

if [[ ! -f "${DIST_ENV}" ]]; then
  echo "missing dist metadata: ${DIST_ENV}" >&2
  exit 1
fi

# shellcheck disable=SC1090
source "${DIST_ENV}"

require_cmd() {
  local cmd
  for cmd in "$@"; do
    command -v "${cmd}" >/dev/null 2>&1 || {
      echo "missing command: ${cmd}" >&2
      exit 1
    }
  done
}

require_cmd dpkg-scanpackages gzip md5sum sha256sum sha512sum stat date

PACKAGE_ARCH="$(dpkg-deb -f "${DIST_DIR}/${PACKAGE_FILE}" Architecture)"

APT_SUITE="${APT_SUITE:-stable}"
APT_COMPONENT="${APT_COMPONENT:-main}"
APT_ARCH="${APT_ARCH:-${PACKAGE_ARCH}}"
APT_ORIGIN="${APT_ORIGIN:-mesa-git}"
APT_LABEL="${APT_LABEL:-mesa-git}"
APT_DESCRIPTION="${APT_DESCRIPTION:-Mesa git apt repository}"

POOL_DIR="${APT_DIR}/pool/${APT_COMPONENT}/m/${PACKAGE_NAME}"
BINARY_DIR="${APT_DIR}/dists/${APT_SUITE}/${APT_COMPONENT}/binary-${APT_ARCH}"
PACKAGE_PATH="${POOL_DIR}/${PACKAGE_FILE}"

rm -rf "${APT_DIR}"
mkdir -p "${POOL_DIR}" "${BINARY_DIR}"

cp "${DIST_DIR}/${PACKAGE_FILE}" "${PACKAGE_PATH}"

(
  cd "${APT_DIR}"
  dpkg-scanpackages --arch "${APT_ARCH}" "pool" > "${BINARY_DIR#${APT_DIR}/}/Packages"
)

gzip -kf "${BINARY_DIR}/Packages"

cat > "${APT_DIR}/dists/${APT_SUITE}/Release" <<EOF
Origin: ${APT_ORIGIN}
Label: ${APT_LABEL}
Suite: ${APT_SUITE}
Codename: ${APT_SUITE}
Architectures: ${APT_ARCH}
Components: ${APT_COMPONENT}
Description: ${APT_DESCRIPTION}
Date: $(date -Ru)
EOF

append_checksum_block() {
  local label="${1}"
  local checksum_cmd="${2}"
  local release_file="${APT_DIR}/dists/${APT_SUITE}/Release"
  local rel_dir="${APT_DIR}/dists/${APT_SUITE}"
  local file
  local sum
  local size
  local rel_path

  printf '%s:\n' "${label}" >> "${release_file}"

  while IFS= read -r -d '' file; do
    rel_path="${file#${rel_dir}/}"
    sum="$(${checksum_cmd} "${file}" | awk '{print $1}')"
    size="$(stat -c '%s' "${file}")"
    printf ' %s %16s %s\n' "${sum}" "${size}" "${rel_path}" >> "${release_file}"
  done < <(find "${rel_dir}" -type f ! -name Release -print0 | sort -z)
}

append_checksum_block "MD5Sum" md5sum
append_checksum_block "SHA256" sha256sum
append_checksum_block "SHA512" sha512sum

if [[ -n "${APT_PUBLIC_BASE_URL:-}" ]]; then
  printf 'deb [trusted=yes] %s %s %s\n' \
    "${APT_PUBLIC_BASE_URL%/}" \
    "${APT_SUITE}" \
    "${APT_COMPONENT}" \
    > "${APT_DIR}/${PACKAGE_NAME}-${APT_SUITE}.list"
fi