import 'dart:convert';

import 'package:flutter/foundation.dart';
import 'package:yumi/shared/data_sources/sources/local/data_persistence.dart';

class LastWeeklyCPSplashEntry {
  const LastWeeklyCPSplashEntry({
    required this.rank,
    required this.leftAvatarUrl,
    required this.rightAvatarUrl,
    required this.leftNickname,
    required this.rightNickname,
  });

  final int rank;
  final String leftAvatarUrl;
  final String rightAvatarUrl;
  final String leftNickname;
  final String rightNickname;

  factory LastWeeklyCPSplashEntry.fromJson(Map<String, dynamic> json) {
    return LastWeeklyCPSplashEntry(
      rank: (json['rank'] as num?)?.toInt() ?? 0,
      leftAvatarUrl: (json['leftAvatarUrl'] as String?) ?? '',
      rightAvatarUrl: (json['rightAvatarUrl'] as String?) ?? '',
      leftNickname: (json['leftNickname'] as String?) ?? '',
      rightNickname: (json['rightNickname'] as String?) ?? '',
    );
  }

  Map<String, dynamic> toJson() {
    return {
      'rank': rank,
      'leftAvatarUrl': leftAvatarUrl,
      'rightAvatarUrl': rightAvatarUrl,
      'leftNickname': leftNickname,
      'rightNickname': rightNickname,
    };
  }
}

class LastWeeklyCPSplashCache {
  static const String _cacheKey = 'last_weekly_cp_splash_cache_v1';

  /// 搜索 `api-ready-launch-splash` 可以快速找到后续要恢复接入的位置。
  ///
  /// 当前 CP 榜接口还没 ready，因此先彻底关闭这套自定义启动页。
  /// 正式恢复时保持“本地有缓存才展示、无缓存不展示”的逻辑，不要再写占位缓存。
  static const bool _allowCacheDrivenSplash = false;

  static bool get shouldShow {
    if (!_allowCacheDrivenSplash) {
      return false;
    }
    return loadCachedEntries().isNotEmpty;
  }

  static List<LastWeeklyCPSplashEntry> loadDisplayEntries() {
    if (!_allowCacheDrivenSplash) {
      return const [];
    }
    return loadCachedEntries();
  }

  static List<LastWeeklyCPSplashEntry> loadCachedEntries() {
    final raw = DataPersistence.getString(_cacheKey);
    if (raw.isEmpty) {
      return const [];
    }

    try {
      final decoded = jsonDecode(raw);
      if (decoded is! List) {
        return const [];
      }
      return decoded
          .whereType<Map>()
          .map(
            (item) => LastWeeklyCPSplashEntry.fromJson(
              Map<String, dynamic>.from(item),
            ),
          )
          .toList()
        ..sort((a, b) => a.rank.compareTo(b.rank));
    } catch (error, stackTrace) {
      debugPrint('LastWeeklyCPSplashCache parse failed: $error\n$stackTrace');
      return const [];
    }
  }

  static Future<void> refreshCacheInBackground() async {
    // TODO(api-ready-launch-splash): CP 榜接口 ready 后，把 `_allowCacheDrivenSplash`
    // 改为 true，并在这里补上“接口取数 -> 映射 LastWeeklyCPSplashEntry ->
    // 写入 `_cacheKey`”的流程。保留“有缓存才展示、无缓存不展示”的正式逻辑。
    if (!_allowCacheDrivenSplash) {
      return;
    }

    try {
      // 当前占位逻辑已下线，等待正式 CP 榜接口接入。
    } catch (error, stackTrace) {
      debugPrint('LastWeeklyCPSplashCache refresh failed: $error\n$stackTrace');
    }
  }
}