powerage-ristoris-flutter/lib/database/db_connector_io.dart

import 'dart:io';
import 'package:drift/native.dart';
import 'package:drift/drift.dart';
import 'package:path/path.dart' as p;
import 'package:path_provider/path_provider.dart';
import 'package:flutter/services.dart' show rootBundle;
import '../core/constants.dart';

QueryExecutor createDb(String dirPath, String dbName) {
  return NativeDatabase(File(p.join(dirPath, dbName)));
}

Future<String> ensureDbReady() async {
  final dir = await getApplicationDocumentsDirectory();
  final dbFile = File(p.join(dir.path, AppConstants.kDbName));
  if (!await dbFile.exists()) {
    try {
      final data = await rootBundle.load(AppConstants.kAssetsDbPath);
      await dbFile.create(recursive: true);
      await dbFile.writeAsBytes(data.buffer.asUint8List());
    } catch (_) {
      // No seed DB in assets, will create empty
    }
  }
  return dir.path;
}

Future<bool> isDatabaseEmpty(String dirPath) async {
  final dbFile = File(p.join(dirPath, AppConstants.kDbName));
  if (!await dbFile.exists()) return true;
  final stat = await dbFile.stat();
  return stat.size < 1024;
}