#!/bin/sh
set -eu

backup_file="${1:-}"
[ -f "$backup_file" ] || { echo "Restore-drill backup not found: $backup_file" >&2; exit 1; }

timestamp="$(date -u +%Y%m%d%H%M%S)"
drill_database="mobilityops_restore_drill_$timestamp"
source_database="${POSTGRES_DB:-mobilityops}"
database_host="${POSTGRES_HOST:-db}"

cleanup() {
  dropdb --if-exists --force --host="$database_host" --username="$POSTGRES_USER" \
    "$drill_database" > /dev/null 2>&1 || true
}
trap cleanup EXIT INT TERM

source_revision="$(psql --host="$database_host" --username="$POSTGRES_USER" \
  --dbname="$source_database" --tuples-only --no-align \
  --command='SELECT version_num FROM alembic_version')"
[ -n "$source_revision" ] || { echo "Source Alembic revision is unavailable" >&2; exit 1; }

createdb --host="$database_host" --username="$POSTGRES_USER" "$drill_database"
pg_restore --no-owner --no-acl --host="$database_host" --username="$POSTGRES_USER" \
  --dbname="$drill_database" "$backup_file"

restored_revision="$(psql --host="$database_host" --username="$POSTGRES_USER" \
  --dbname="$drill_database" --tuples-only --no-align \
  --command='SELECT version_num FROM alembic_version')"
[ "$restored_revision" = "$source_revision" ] || {
  echo "Restored Alembic revision does not match production" >&2
  exit 1
}

counts="$(psql --host="$database_host" --username="$POSTGRES_USER" \
  --dbname="$drill_database" --tuples-only --no-align --field-separator=, \
  --command='SELECT (SELECT count(*) FROM users), (SELECT count(*) FROM vehicles), (SELECT count(*) FROM bookings), (SELECT count(*) FROM audit_events)')"
case "$counts" in
  0,*|*,0,*|*,*,0,*|*,*,*,0) echo "Restored database is missing canonical records: $counts" >&2; exit 1 ;;
esac

cleanup
trap - EXIT INT TERM
echo "Restore drill passed: revision=$restored_revision counts=$counts"