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

# Deterministic dataset builder for STORE-AOC-19-005-DEV.
# Generates linksets-stage-backfill.tar.zst from repo seed data.
# Usage:
#   ./scripts/concelier/build-store-aoc-19-005-dataset.sh [output_tarball]
# Default output: out/linksets/linksets-stage-backfill.tar.zst

command -v tar >/dev/null || { echo "tar is required" >&2; exit 1; }
command -v sha256sum >/dev/null || { echo "sha256sum is required" >&2; exit 1; }

TAR_COMPRESS=()
if command -v zstd >/dev/null 2>&1; then
  TAR_COMPRESS=(--zstd)
else
  echo "zstd not found; building uncompressed tarball (extension kept for compatibility)" >&2
fi

ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
SEED_DIR="${ROOT_DIR}/seed-data/concelier/store-aoc-19-005"
OUT_DIR="${ROOT_DIR}/out/linksets"
OUT_PATH="${1:-${OUT_DIR}/linksets-stage-backfill.tar.zst}"
GEN_TIME="2025-12-07T00:00:00Z"

for seed in linksets.ndjson advisory_chunks.ndjson; do
  if [[ ! -f "${SEED_DIR}/${seed}" ]]; then
    echo "Missing seed file: ${SEED_DIR}/${seed}" >&2
    exit 1
  fi
done

WORKDIR="$(mktemp -d)"
cleanup() { rm -rf "${WORKDIR}"; }
trap cleanup EXIT

cp "${SEED_DIR}/linksets.ndjson" "${WORKDIR}/linksets.ndjson"
cp "${SEED_DIR}/advisory_chunks.ndjson" "${WORKDIR}/advisory_chunks.ndjson"

linksets_sha=$(sha256sum "${WORKDIR}/linksets.ndjson" | awk '{print $1}')
advisory_sha=$(sha256sum "${WORKDIR}/advisory_chunks.ndjson" | awk '{print $1}')
linksets_count=$(wc -l < "${WORKDIR}/linksets.ndjson" | tr -d '[:space:]')
advisory_count=$(wc -l < "${WORKDIR}/advisory_chunks.ndjson" | tr -d '[:space:]')

cat >"${WORKDIR}/manifest.json" <<EOF
{
  "datasetId": "store-aoc-19-005-dev",
  "generatedAt": "${GEN_TIME}",
  "source": "seed-data/concelier/store-aoc-19-005",
  "records": {
    "linksets": ${linksets_count},
    "advisory_chunks": ${advisory_count}
  },
  "sha256": {
    "linksets.ndjson": "${linksets_sha}",
    "advisory_chunks.ndjson": "${advisory_sha}"
  }
}
EOF

mkdir -p "${OUT_DIR}"

tar "${TAR_COMPRESS[@]}" \
    --format=ustar \
    --mtime='1970-01-01 00:00:00Z' \
    --owner=0 --group=0 --numeric-owner \
    -cf "${OUT_PATH}" \
    -C "${WORKDIR}" \
    linksets.ndjson advisory_chunks.ndjson manifest.json

sha256sum "${OUT_PATH}" > "${OUT_PATH}.sha256"

echo "Wrote ${OUT_PATH}"
cat "${OUT_PATH}.sha256"