set -euo pipefail

if [ "$#" -ne 2 ]; then

echo "Usage: $0 <project_dir> <cache_key>" >&2

exit 1

project_dir="$1"

cache_key="$2"

cd "$project_dir"

lock_file="package-lock.json"

stamp_file="node_modules/.package-lock.hash"

npm_cache_dir="/tmp/npm-cache/$cache_key"

if [ ! -f "$lock_file" ]; then

echo "Missing $lock_file in $project_dir" >&2

exit 1

lock_hash="$(sha256sum "$lock_file" | cut -d' ' -f1)"

cached_hash="$(cat "$stamp_file" 2>/dev/null || true)"

if [ -d node_modules ] && [ "$lock_hash" = "$cached_hash" ]; then

echo "[ensure_node_modules] Reusing $project_dir/node_modules (lockfile unchanged)"

exit 0

echo "[ensure_node_modules] Installing dependencies for $project_dir with npm ci"

rm -rf node_modules

mkdir -p "$npm_cache_dir"

if ! npm_config_cache="$npm_cache_dir" npm ci --no-audit --no-fund; then

echo "[ensure_node_modules] Initial npm ci failed for $project_dir, clearing cache and retrying"

rm -rf node_modules "$npm_cache_dir"

mkdir -p "$npm_cache_dir"

npm_config_cache="$npm_cache_dir" npm ci --no-audit --no-fund

printf '%s\n' "$lock_hash" > "$stamp_file"