import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../core/network/api_exception.dart';
import '../models/membership_models.dart';
import '../services/membership_service.dart';
import '../services/user_service.dart';
import 'auth_provider.dart';

/// 会员中心状态
class MemberState {
  const MemberState({
    this.plans = const [],
    this.benefits = const [],
    this.me,
    this.isLoading = false,
    this.loadFailed = false,
    this.redeeming = false,
  });

  final List<MembershipPlan> plans;
  final List<String> benefits;
  final MyMemberState? me;
  final bool isLoading;
  final bool loadFailed;
  final bool redeeming;

  MemberState copyWith({
    List<MembershipPlan>? plans,
    List<String>? benefits,
    MyMemberState? me,
    bool? isLoading,
    bool? loadFailed,
    bool? redeeming,
  }) =>
      MemberState(
        plans: plans ?? this.plans,
        benefits: benefits ?? this.benefits,
        me: me ?? this.me,
        isLoading: isLoading ?? this.isLoading,
        loadFailed: loadFailed ?? this.loadFailed,
        redeeming: redeeming ?? this.redeeming,
      );
}

/// 会员中心 Notifier：套餐列表 + 我的会员状态 + 积分开通
class MemberNotifier extends StateNotifier<MemberState> {
  MemberNotifier(this._ref) : super(const MemberState()) {
    load();
  }

  final Ref _ref;

  Future<void> load() async {
    state = state.copyWith(isLoading: true, loadFailed: false);
    try {
      final plans = await MembershipService.fetchPlans();
      MyMemberState? me;
      // 游客无会员状态接口权限，未登录时跳过
      if (_ref.read(authProvider).isLoggedIn) {
        me = await MembershipService.fetchMe();
      }
      state = state.copyWith(
        plans: plans.plans,
        benefits: plans.benefits,
        me: me,
        isLoading: false,
      );
    } catch (_) {
      state = state.copyWith(isLoading: false, loadFailed: true);
    }
  }

  /// 积分开通会员。
  /// 成功返回结果文案；失败抛 [ApiException] 由 UI 提示（2001 积分不足 / 2004 终身卡重复开通）。
  Future<RedeemResult> redeem(String planCode) async {
    state = state.copyWith(redeeming: true);
    try {
      final result = await MembershipService.redeem(planCode);
      // 刷新我的会员状态 + 全局用户信息（积分/会员标识已变化）
      final me = await MembershipService.fetchMe();
      final user = await UserService.fetchMe();
      state = state.copyWith(me: me, redeeming: false);
      await _ref.read(authProvider.notifier).onLoginSuccess(user);
      return result;
    } catch (_) {
      state = state.copyWith(redeeming: false);
      rethrow;
    }
  }
}

/// autoDispose：进入会员页时创建并加载，离开即销毁；登录态变化后自动取最新
final memberProvider = StateNotifierProvider.autoDispose<MemberNotifier, MemberState>(
  MemberNotifier.new,
);