#!/usr/bin/env bash
set -Eeuo pipefail
if [[ $# -lt 1 || $# -gt 2 || ( $# -eq 2 && "${2:-}" != --offline ) ]]; then
  echo 'Usage: bash restore.sh /absolute/path/to/environment [--offline]' >&2
  exit 2
fi
TARGET=$(readlink -m -- "$1")
if [[ -e "$TARGET" && ( ! -d "$TARGET" || -n "$(ls -A "$TARGET")" ) ]]; then
  echo "Refusing to overwrite a nonempty environment: $TARGET" >&2
  exit 2
fi
SCRIPT_DIR=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)
if [[ -f "$SCRIPT_DIR/SHA256SUMS" && -d "$SCRIPT_DIR/archives" ]]; then
  DEFAULT_CACHE=$SCRIPT_DIR
else
  DEFAULT_CACHE=$SCRIPT_DIR/simlingo-env-files
fi
CACHE=${SIMLINGO_PACKAGE_CACHE:-$DEFAULT_CACHE}
mkdir -p "$CACHE/archives"
CACHE=$(cd "$CACHE" && pwd)
BASE_URL="https://huggingface.co/datasets/data-loader/simlingo-conda-env/resolve/${SIMLINGO_ENV_REVISION:-main}"
OFFLINE=${2:-}
ARCHIVES=(archives/simlingo-linux-x86_64-py38-20261015.tar.gz.part-000 archives/simlingo-linux-x86_64-py38-20261015.tar.gz.part-001 archives/simlingo-linux-x86_64-py38-20261015.tar.gz.part-002 archives/simlingo-linux-x86_64-py38-20261015.tar.gz.part-003)
METADATA=(manifest.json packages.json environment-info.json requirements-snapshot.txt restore-validation.json public-audit.json THIRD_PARTY_NOTICES.md)
download() {
  local rel=$1
  local file="$CACHE/$rel"
  if [[ "$OFFLINE" == --offline ]]; then
    test -f "$file" || { echo "Missing offline file: $rel" >&2; exit 2; }
    return
  fi
  if [[ "$rel" != SHA256SUMS && -f "$file" && -f "$CACHE/SHA256SUMS" ]]; then
    if (cd "$CACHE" && awk -v f="$rel" '$2 == f { print }' SHA256SUMS | sha256sum -c --status); then
      return
    fi
  fi
  curl --fail --location --retry 3 --connect-timeout 30     --continue-at - --output "$file.partial" "$BASE_URL/$rel"
  mv -- "$file.partial" "$file"
}
download SHA256SUMS
for rel in "${METADATA[@]}" "${ARCHIVES[@]}"; do download "$rel"; done
(cd "$CACHE" && sha256sum -c SHA256SUMS)
mkdir -p "$TARGET"
ARCHIVE_PATHS=()
for rel in "${ARCHIVES[@]}"; do ARCHIVE_PATHS+=("$CACHE/$rel"); done
cat "${ARCHIVE_PATHS[@]}" | tar --no-same-owner -xz -C "$TARGET"
set +u
source "$TARGET/bin/activate"
set -u
hash -r
test "$(command -v python)" = "$TARGET/bin/python"
python "$TARGET/bin/conda-unpack"
python -c 'import sys, torch; print("Python:", sys.executable); print("PyTorch:", torch.__version__)'
printf '\nEnvironment ready. In your shell run:\nsource %q/bin/activate\n' "$TARGET"