import 'package:supabase_flutter/supabase_flutter.dart';

import '../../../feed/domain/models/feed_post_model.dart';
import '../../../music/domain/models/track_model.dart';
import '../../domain/models/discover_data_model.dart';
import '../../domain/models/trending_user_model.dart';

class DiscoverService {
  const DiscoverService(this._client);

  final SupabaseClient _client;

  Future<DiscoverDataModel> fetchDiscoverData() async {
    final users = await _fetchTrendingUsers();
    final posts = await _fetchTrendingPosts();
    final tracks = await _fetchTrendingTracks();

    return DiscoverDataModel(
      trendingUsers: users,
      trendingPosts: posts,
      trendingTracks: tracks,
    );
  }

  Future<List<TrendingUserModel>> _fetchTrendingUsers() async {
    // Trending users based on total engagement (mocking for now by fetching profiles)
    final profiles = List<Map<String, dynamic>>.from(
      await _client
          .from('profiles')
          .select('user_id, username, avatar_url')
          .limit(20),
    );

    final users = <TrendingUserModel>[];
    for (final profile in profiles) {
      final userId = profile['user_id'] as String;
      
      final postsResponse = await _client
          .from('posts')
          .select('*')
          .eq('user_id', userId);
          
      final tracksResponse = await _client
          .from('tracks')
          .select('*')
          .eq('user_id', userId);

      users.add(
        TrendingUserModel(
          userId: userId,
          username: (profile['username'] as String?) ?? 'RIOT_USER',
          avatarUrl: (profile['avatar_url'] as String?) ?? '',
          postsCount: (postsResponse as List).length,
          tracksCount: (tracksResponse as List).length,
        ),
      );
    }

    // Sort by total content count
    users.sort((a, b) => (b.postsCount + b.tracksCount).compareTo(a.postsCount + a.tracksCount));
    return users.take(10).toList();
  }

  Future<List<FeedPostModel>> _fetchTrendingPosts() async {
    final rows = List<Map<String, dynamic>>.from(
      await _client
          .from('posts')
          .select('id, user_id, caption, image_url, likes_count, created_at, profiles(username, avatar_url)')
          .order('likes_count', ascending: false)
          .limit(10),
    );

    return rows.map((row) {
      final profile = (row['profiles'] as Map<String, dynamic>?) ?? {};
      return FeedPostModel(
        id: row['id'] as String,
        userId: row['user_id'] as String,
        caption: (row['caption'] as String?) ?? '',
        imageUrl: (row['image_url'] as String?) ?? '',
        createdAt: DateTime.parse(row['created_at'] as String),
        likesCount: (row['likes_count'] as int?) ?? 0,
        isLiked: false, // Default to false for discover
        username: (profile['username'] as String?) ?? 'RIOTER',
        avatarUrl: (profile['avatar_url'] as String?) ?? '',
      );
    }).toList();
  }

  Future<List<TrackModel>> _fetchTrendingTracks() async {
    final rows = await _client
        .from('tracks')
        .select('*, profiles(username)')
        .order('plays', ascending: false)
        .limit(10);
        
    return List<Map<String, dynamic>>.from(rows).map((row) {
      final username = (row['profiles'] as Map<String, dynamic>?)?['username'] as String?;
      return TrackModel.fromJson(row, username: username);
    }).toList();
  }
}