/// ============================================================
/// 【课堂习题 · 收藏 / 错题本】（1:1 迁移 Vue exerciseCollect.js）
///
/// type=1 收藏；type=2 错题（仅 view 模式可用）。
/// ============================================================
library;

import 'package:new_learn/core/api/conquerPackage/classExercises/api.dart';
import 'package:new_learn/features/conquerPackage/classExercises/controllers/exercise_session.dart';
import 'package:new_learn/features/conquerPackage/classExercises/models/question_model.dart';

class ExerciseCollectHandlers {
  ExerciseCollectHandlers({
    required this.session,
    required this.bridge,
  });

  final ExerciseSession session;
  final ExerciseUiBridge bridge;
  final ClassExercisesApi _api = ClassExercisesApi.instance;

  dynamic _field(dynamic resp, String key) {
    if (resp is Map) {
      if (resp[key] != null) return resp[key];
      final data = resp['data'];
      if (data is Map && data[key] != null) return data[key];
    }
    return null;
  }

  /// type：1=收藏，2=错题本
  Future<void> onClickAddUserCollect(int type) async {
    // 错题仅查看模式可用
    if (type == 2 && !session.isView) return;

    final info = session.currentQuestion;
    if (info == null) return;

    final selected = type == 1 ? info.isCollect : info.isWrongCollect;
    try {
      if (selected) {
        final id = type == 1 ? info.collectId : info.wrongCollectId;
        await _api.cancleCollect(<String, dynamic>{
          'type': type,
          'id': id ?? 0,
        });
        _syncCollectState(type, true, null, info);
        bridge.toast(type == 1 ? '取消收藏成功' : '取消错题成功');
      } else {
        final packId =
            session.totalPackId.isNotEmpty ? session.totalPackId : session.packId;
        final res = await _api.addUserCollect(<String, dynamic>{
          'type': type,
          'packId': packId,
          'questionId': info.questionId,
          'recordQuestionId': info.id,
        });
        final resId = _field(res, 'id');
        _syncCollectState(type, false, resId, info);
        bridge.toast(type == 1 ? '收藏成功' : '错题添加成功');
      }
      bridge.notifyListeners();
    } catch (_) {
      bridge.toast(type == 1 ? '收藏失败' : '失败');
    }
  }

  /// 同步收藏态（对标 syncCollectState）
  void _syncCollectState(
    int type,
    bool wasSelected,
    dynamic resId,
    QuestionModel info,
  ) {
    if (type == 2) {
      info.isWrongCollect = !wasSelected;
      info.wrongCollectId = wasSelected ? 0 : resId;
    } else {
      info.isCollect = !wasSelected;
      info.collectId = wasSelected ? 0 : resId;
    }
  }
}