How can I implement offline data sync in a Flutter app using local storage?

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    // Example of using sqflite for local storage
    import 'package:sqflite/sqflite.dart';
    import 'package:path/path.dart';

    Future<Database> openDatabase() async {
      return openDatabase(
        join(await getDatabasesPath(), 'app_database.db'),
        onCreate: (db, version) {
          return db.execute(
            "CREATE TABLE items(id INTEGER PRIMARY KEY, data TEXT)",
          );
        },
        version: 1,
      );
    }

    Future<void> insertItem(Database db, Map<String, dynamic> item) async {
      await db.insert(
        'items',
        item,
        conflictAlgorithm: ConflictAlgorithm.replace,
      );
    }

    // Sync function to be called when online
    Future<void> syncData(Database db) async {
      final List<Map<String, dynamic>> items = await db.query('items');
      // Perform network request to sync data
      // Example: await http.post('https://api.example.com/sync', body: items);
    }
    <!-- END COPY / PASTE -->