// 🏆 학년별 공부시간 랭킹 화면의 기능(서버 통신/상태) 담당 컨트롤러.
import 'dart:convert';
import 'package:flutter/foundation.dart';
import 'package:http/http.dart' as http;
import '../config.dart';

class StudyRankingController extends ChangeNotifier {
  final int grade;

  StudyRankingController({required this.grade});

  bool _isLoading = true;
  String _period = 'today'; // today / week / total
  String _scope = 'grade'; // grade / all
  List<dynamic> _ranking = [];

  bool get isLoading => _isLoading;
  String get period => _period;
  String get scope => _scope;
  List<dynamic> get ranking => _ranking;

  Future<void> init() => fetchRanking();

  Future<void> setPeriod(String period) async {
    if (_period == period) return;
    _period = period;
    await fetchRanking();
  }

  Future<void> setScope(String scope) async {
    if (_scope == scope) return;
    _scope = scope;
    await fetchRanking();
  }

  Future<void> fetchRanking() async {
    _isLoading = true;
    notifyListeners();
    try {
      final gradeParam = _scope == 'grade' ? '&grade=$grade' : '';
      final response = await http.get(
        Uri.parse('$baseUrl/api/study/ranking?period=$_period$gradeParam'),
      );
      if (response.statusCode == 200) {
        final data = jsonDecode(utf8.decode(response.bodyBytes));
        _ranking = data['ranking'] ?? [];
      }
    } catch (_) {
      // 조용히 무시 - 마지막으로 받아온 랭킹을 유지한다.
    } finally {
      _isLoading = false;
      notifyListeners();
    }
  }
}