#!/usr/bin/env bash
# Refresh the local development database from a fresh production dump.
#
# Prod is the source of truth for data; dev is a disposable copy of it.
#
# Required env (put them in .env.dev-refresh or export them; never commit real values):
#   PROD_DB_URL    read access to prod, e.g. postgresql://personal:...@127.0.0.1:5440/personal
#   DEV_ADMIN_URL  superuser on the dev cluster, maintenance DB, e.g. postgresql://postgres:...@127.0.0.1:5432/postgres
# Optional:
#   DEV_DB_NAME    target database (default personal_dev)
#   PG_DOCKER=1    use the postgres:17-alpine image instead of local pg_dump/pg_restore
#
# What it does: dump prod (custom format) -> drop + recreate DEV_DB_NAME -> create
# missing roles (NOLOGIN) -> restore with ownership/grants intact -> clear sessions
# and verification tokens so prod logins can't be reused in dev. It never writes to prod.
set -euo pipefail

cd "$(dirname "$0")/.."
if [[ -f .env.dev-refresh ]]; then set -a; . ./.env.dev-refresh; set +a; fi

: "${PROD_DB_URL:?set PROD_DB_URL (source, read-only use)}"
: "${DEV_ADMIN_URL:?set DEV_ADMIN_URL (superuser URL to the dev cluster maintenance DB)}"
DEV_DB_NAME="${DEV_DB_NAME:-personal_dev}"

if [[ ! "$DEV_DB_NAME" =~ ^[a-z_][a-z0-9_]*$ ]]; then
	echo "DEV_DB_NAME must be a plain lowercase identifier" >&2
	exit 1
fi
case "$DEV_DB_NAME" in
personal | personal_prod | postgres | template0 | template1)
	echo "Refusing to overwrite '$DEV_DB_NAME'" >&2
	exit 1
	;;
esac

# host:port/db of a URL (no credentials), for the "same database" guard.
endpoint() { bun -e 'const u=new URL(process.argv[1]); console.log(`${u.hostname}:${u.port||5432}${u.pathname}`)' "$1"; }
with_db() { bun -e 'const u=new URL(process.argv[1]); u.pathname="/"+process.argv[2]; console.log(u.toString())' "$1" "$2"; }

prod_endpoint="$(endpoint "$PROD_DB_URL")"
dev_url="$(with_db "$DEV_ADMIN_URL" "$DEV_DB_NAME")"
if [[ "$(endpoint "$dev_url")" == "$prod_endpoint" ]]; then
	echo "Refusing: target $DEV_DB_NAME is the prod source database ($prod_endpoint)" >&2
	exit 1
fi

if [[ "${PG_DOCKER:-0}" == 1 ]]; then
	pg() { docker run --rm -i --network host -v "$work:$work" postgres:17-alpine "$@"; }
else
	pg() { "$@"; }
fi

work="$(mktemp -d)"
trap 'rm -rf "$work"' EXIT
dump="$work/prod.dump"

echo "Dumping prod ($prod_endpoint)..."
pg pg_dump --format=custom --no-password --file="$dump" "$PROD_DB_URL"

echo "Recreating $DEV_DB_NAME..."
pg psql -v ON_ERROR_STOP=1 -q "$DEV_ADMIN_URL" <<SQL
SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE datname = '$DEV_DB_NAME' AND pid <> pg_backend_pid();
DROP DATABASE IF EXISTS "$DEV_DB_NAME";
DO \$\$
DECLARE r text;
BEGIN
  FOREACH r IN ARRAY ARRAY['personal','personal_app','personal_ddl','personal_ro'] LOOP
    IF NOT EXISTS (SELECT 1 FROM pg_roles WHERE rolname = r) THEN
      EXECUTE format('CREATE ROLE %I NOLOGIN', r);
      RAISE NOTICE 'created role % (NOLOGIN; give it a password + LOGIN for dev use)', r;
    END IF;
  END LOOP;
END \$\$;
CREATE DATABASE "$DEV_DB_NAME" OWNER personal;
SQL

echo "Restoring into $DEV_DB_NAME..."
pg pg_restore --no-password --exit-on-error --dbname="$dev_url" "$dump"

echo "Clearing sessions and verification tokens..."
pg psql -v ON_ERROR_STOP=1 -q "$dev_url" -c 'TRUNCATE auth.session, auth.verification'

pg psql -qAt "$dev_url" -c "SELECT 'drizzle migrations recorded: ' || count(*) FROM drizzle.__drizzle_migrations"
echo "Done. Apply pending migrations from your branch with: bun run db:migrate"