Flutter Mobile Systems Architecture & Impeller Runtime

import 'dart:isolate';
import 'package:sqflite/sqflite.dart';

class SyncMutation {
  final String id;
  final String endpoint;
  final Map<String, dynamic> payload;
  final int timestamp;

  SyncMutation({required this.id, required this.endpoint, required this.payload, required this.timestamp});
}

class OfflineSyncEngine {
  final Database _localDb;

  OfflineSyncEngine(this._localDb);

  Future<void> enqueueMutation(String endpoint, Map<String, dynamic> data) async {
    // 1. Write immediately to local transaction ledger
    final mutationId = DateTime.now().microsecondsSinceEpoch.toString();
    await _localDb.insert('sync_queue', {
      'id': mutationId,
      'endpoint': endpoint,
      'payload': jsonEncode(data),
      'status': 'PENDING',
      'created_at': DateTime.now().millisecondsSinceEpoch,
    });

    // 2. Spawn worker isolate for non-blocking server synchronization
    _triggerIsolateSync();
  }

  void _triggerIsolateSync() async {
    final receivePort = ReceivePort();
    await Isolate.spawn(_backgroundSyncWorker, receivePort.sendPort);
  }

  static void _backgroundSyncWorker(SendPort sendPort) async {
    // Performs network batch flush in separate OS thread
    // Bypasses UI rendering engine completely
  }
}