nj/app/lib/features/achievement/bloc/achievement_bloc.dart

// 成就 BLoC — 通过 API 加载成就列表

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:nuanji_app/data/remote/api_client.dart';

// ===== 模型 =====

/// 成就数据
class Achievement {
  final String id;
  final String code;
  final String name;
  final String? description;
  final String? icon;
  final String category;
  final bool isUnlocked;
  final DateTime? unlockedAt;

  const Achievement({
    required this.id,
    required this.code,
    required this.name,
    this.description,
    this.icon,
    required this.category,
    this.isUnlocked = false,
    this.unlockedAt,
  });
}

// ===== State =====

/// 成就页面状态
class AchievementState {
  final List<Achievement> achievements;
  final bool isLoading;
  final String? errorMessage;

  const AchievementState({
    this.achievements = const [],
    this.isLoading = false,
    this.errorMessage,
  });

  int get unlockedCount =>
      achievements.where((a) => a.isUnlocked).length;

  AchievementState copyWith({
    List<Achievement>? achievements,
    bool? isLoading,
    String? errorMessage,
  }) =>
      AchievementState(
        achievements: achievements ?? this.achievements,
        isLoading: isLoading ?? this.isLoading,
        errorMessage: errorMessage,
      );
}

// ===== BLoC =====

/// 成就 BLoC — ChangeNotifier 模式
class AchievementBloc extends ChangeNotifier {
  final ApiClient _api;
  AchievementState _state = const AchievementState();
  AchievementState get state => _state;

  AchievementBloc({required ApiClient api}) : _api = api;

  /// 加载成就列表
  void load() {
    _state = _state.copyWith(isLoading: true);
    notifyListeners();
    _fetchAchievements();
  }

  Future<void> _fetchAchievements() async {
    try {
      final response = await _api.get('/diary/achievements');
      final body = response.data as Map<String, dynamic>;
      final list = body['data'] as List? ?? [];

      final achievements = list.map((item) {
        final m = item as Map<String, dynamic>;
        return Achievement(
          id: m['id'] as String,
          code: m['code'] as String,
          name: m['name'] as String,
          description: m['description'] as String?,
          icon: m['icon'] as String?,
          category: m['category'] as String,
          isUnlocked: m['is_unlocked'] as bool? ?? false,
          unlockedAt: m['unlocked_at'] != null
              ? DateTime.tryParse(m['unlocked_at'] as String)
              : null,
        );
      }).toList();

      _state = _state.copyWith(isLoading: false, achievements: achievements);
    } catch (e) {
      debugPrint('AchievementBloc._fetchAchievements 失败: $e');
      _state = _state.copyWith(
        isLoading: false,
        errorMessage: '加载成就列表失败',
      );
    }
    notifyListeners();
  }
}