scripts/unpack_data.sh

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

ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
ARCHIVE_DIR="${ROOT_DIR}/data"
DATA_ROOT="${1:-${ROOT_DIR}/data}"

mkdir -p "${DATA_ROOT}"

declare -A selected_archives=()

while IFS= read -r archive; do
  filename="$(basename "${archive}")"
  base="${filename}"
  if [[ "${filename}" == *.tar.zst ]]; then
    base="${filename%.tar.zst}"
  elif [[ "${filename}" == *.tar ]]; then
    base="${filename%.tar}"
  else
    continue
  fi

  if [[ -n "${selected_archives[${base}]:-}" ]]; then
    echo "found multiple archive variants for ${base} under ${ARCHIVE_DIR}; keep only one of .tar or .tar.zst" >&2
    exit 1
  fi
  selected_archives["${base}"]="${archive}"
done < <(find "${ARCHIVE_DIR}" -maxdepth 1 -type f \( -name '*.tar' -o -name '*.tar.zst' \) | sort)

if [[ "${#selected_archives[@]}" -eq 0 ]]; then
  echo "no archives found under ${ARCHIVE_DIR}" >&2
  exit 1
fi

mapfile -t archive_bases < <(printf '%s\n' "${!selected_archives[@]}" | sort)
for base in "${archive_bases[@]}"; do
  archive="${selected_archives[${base}]}"
  echo "extracting ${archive}"
  case "${archive}" in
    *.tar.zst)
      tar --zstd -xf "${archive}" -C "${DATA_ROOT}"
      ;;
    *.tar)
      tar -xf "${archive}" -C "${DATA_ROOT}"
      ;;
    *)
      echo "unsupported archive format: ${archive}" >&2
      exit 1
      ;;
  esac
done

echo "raw data extracted into ${DATA_ROOT}"