import 'package:patbond_flutter/analytics/analytics_service.dart';
import 'package:patbond_flutter/core/network/api_client.dart';
import 'package:patbond_flutter/core/network/api_exception.dart';
import 'package:patbond_flutter/core/network/token_refresher.dart';
import 'package:patbond_flutter/features/auth/auth_models.dart';
import 'package:patbond_flutter/features/auth/session_manager.dart';
import 'package:uuid/uuid.dart';

/// Splash 会话恢复的裁决结果。状态切换由 Splash 在最短停留时间后执行。
enum SessionRestoreResult { authenticated, noSession }

/// 认证仓库接口（页面依赖此抽象，widget 测试注入假实现）。
abstract class AuthRepository {
  Future<void> login({required String username, required String password});

  Future<void> register({
    required String username,
    required String phone,
    required String password,
  });

  /// 撤销当前会话并清除本地凭证。服务端调用失败也保证本地清除。
  Future<void> logout();

  /// 启动恢复：本地有 refresh token 则静默刷新。
  /// 网络失败抛 [ApiNetworkException]（token 保留）；
  /// refresh 失效抛 [SessionExpiredException]（会话已清）。
  Future<SessionRestoreResult> restoreSession();

  Future<UserProfile> me();
}

class ApiAuthRepository implements AuthRepository {
  ApiAuthRepository({
    required this._api,
    required this._session,
    required this._refresher,
    AnalyticsService? analytics,
    this._uuid = const Uuid(),
  }) : _analytics = analytics;

  final ApiClient _api;
  final SessionManager _session;
  final TokenRefresher _refresher;
  final AnalyticsService? _analytics;
  final Uuid _uuid;

  @override
  Future<void> login({
    required String username,
    required String password,
  }) async {
    final startTime = DateTime.now();
    try {
      final data = await _api.request(
        '/api/v1/auth/login',
        body: {'username': username, 'password': password},
      );
      await _session.saveSession(
        AuthTokens.fromJson(data! as Map<String, dynamic>),
      );
      _analytics?.identify(_session.userId!);
      _analytics?.trackEvent('auth_login_succeeded', {
        'identifierType': 'username',
        'durationMs': DateTime.now().difference(startTime).inMilliseconds,
      });
    } catch (error) {
      _analytics?.trackEvent('auth_login_failed', {
        'identifierType': 'username',
        'failureReason': error.toString(),
      });
      rethrow;
    }
  }

  @override
  Future<void> register({
    required String username,
    required String phone,
    required String password,
  }) async {
    final startTime = DateTime.now();
    try {
      final data = await _api.request(
        '/api/v1/auth/register',
        body: {'username': username, 'phone': phone, 'password': password},
        // 每次提交一个幂等键；token 刷新后的自动重放沿用同一个键。
        headers: {'Idempotency-Key': _uuid.v4()},
      );
      await _session.saveSession(
        AuthTokens.fromJson(data! as Map<String, dynamic>),
      );
      _analytics?.identify(_session.userId!);
      _analytics?.trackEvent('auth_register_succeeded', {
        'durationMs': DateTime.now().difference(startTime).inMilliseconds,
      });
    } catch (error) {
      _analytics?.trackEvent('auth_register_failed', {
        'failureReason': error.toString(),
      });
      rethrow;
    }
  }

  @override
  Future<void> logout() async {
    final refreshToken = _session.refreshToken;
    try {
      await _api.request(
        '/api/v1/auth/logout',
        body: {'refreshToken': refreshToken},
        requiresAuth: true,
      );
    } on ApiException {
      // 服务端撤销失败不阻塞本地登出；refresh 侧最终会自然过期。
    } finally {
      await _session.clearSession();
      _analytics?.reset();
      _analytics?.trackEvent('auth_logout', {'serverRevoked': true});
    }
  }

  @override
  Future<SessionRestoreResult> restoreSession() async {
    await _session.loadFromStorage();
    if (_session.refreshToken == null) {
      return SessionRestoreResult.noSession;
    }
    await _refresher.refresh();
    return SessionRestoreResult.authenticated;
  }

  @override
  Future<UserProfile> me() async {
    final data = await _api.request(
      '/api/v1/me',
      method: 'GET',
      requiresAuth: true,
    );
    return UserProfile.fromJson(data! as Map<String, dynamic>);
  }
}