// Author: fruit.com.cn

import 'package:flutter_test/flutter_test.dart';
import 'package:fruitshorts/core/data/services/auth_session_store.dart';
import 'package:fruitshorts/core/data/services/device_id_provider.dart';
import 'package:shared_preferences_platform_interface/in_memory_shared_preferences_async.dart';
import 'package:shared_preferences_platform_interface/shared_preferences_async_platform_interface.dart';

/// 可控的系统设备标识来源。
class _FakeDeviceIdProvider implements DeviceIdProvider {
  _FakeDeviceIdProvider(this.value, {this.region});

  final String? value;
  final String? region;
  int calls = 0;

  @override
  Future<String?> systemDeviceId() async {
    calls++;
    return value;
  }

  @override
  Future<String?> deviceRegion() async => region;
}

void main() {
  setUp(() {
    SharedPreferencesAsyncPlatform.instance =
        InMemorySharedPreferencesAsync.empty();
  });

  test('should_prefer_system_device_id_over_local_value', () async {
    final provider = _FakeDeviceIdProvider('a-9774d56d682e549c');
    final store = AuthSessionStore(deviceIdProvider: provider);

    expect(await store.deviceId(), 'a-9774d56d682e549c');
  });

  test('should_fall_back_to_stable_local_uuid_when_system_id_missing', () async {
    final store = AuthSessionStore(
      deviceIdProvider: _FakeDeviceIdProvider(null),
    );

    final first = await store.deviceId();
    final second = await store.deviceId();

    // 同一次运行内固定，且符合 UUIDv4 形态
    expect(first, second);
    expect(first, startsWith('d-'));
    expect(
      RegExp(
        r'^d-[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$',
      ).hasMatch(first),
      isTrue,
      reason: '本地兜底必须是 UUIDv4，避免 32 位随机带来的碰撞',
    );
  });

  test('should_cache_system_id_within_one_session', () async {
    final provider = _FakeDeviceIdProvider('i-E621E1F8-C36C-495A-93FC-0C247A3E6E5F');
    final store = AuthSessionStore(deviceIdProvider: provider);

    await store.deviceId();
    await store.deviceId();

    expect(provider.calls, 1);
  });

  test('should_return_device_region_or_empty_string', () async {
    final store = AuthSessionStore(
      deviceIdProvider: _FakeDeviceIdProvider(null, region: 'TH'),
    );
    final missing = AuthSessionStore(
      deviceIdProvider: _FakeDeviceIdProvider(null),
    );

    expect(await store.deviceRegion(), 'TH');
    expect(await missing.deviceRegion(), '');
  });
}