import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:google_fonts/google_fonts.dart';
import '../../../../core/models/playlist_config.dart';
import '../../../../core/theme/app_colors.dart';
import '../../../../core/widgets/components/hero_carousel.dart';
import '../../../../core/widgets/glass_container.dart';
import '../../../../features/iptv/models/xtream_models.dart';
import '../../../../features/iptv/providers/xtream_provider.dart';
import '../../../../features/iptv/providers/settings_provider.dart';
import '../screens/mobile_series_detail_screen.dart';

class MobileSeriesTab extends ConsumerStatefulWidget {
  final PlaylistConfig playlist;
  const MobileSeriesTab({super.key, required this.playlist});

  @override
  ConsumerState<MobileSeriesTab> createState() => _MobileSeriesTabState();
}

class _MobileSeriesTabState extends ConsumerState<MobileSeriesTab> {
  final ScrollController _scrollController = ScrollController();
  final TextEditingController _searchController = TextEditingController();
  final List<Series> _series = [];
  List<Series>? _searchResults;
  String _searchQuery = '';
  bool _isLoading = false;
  bool _isSearching = false;
  bool _hasMore = true;
  int _currentOffset = 0;
  static const int _pageSize = 50;
  Timer? _searchDebounce;

  @override
  void initState() {
    super.initState();
    _loadMoreSeries();
    _scrollController.addListener(_onScroll);
  }

  @override
  void dispose() {
    _scrollController.dispose();
    _searchController.dispose();
    _searchDebounce?.cancel();
    super.dispose();
  }

  void _onScroll() {
    if (!_isLoading &&
        _hasMore &&
        _scrollController.position.pixels >=
            _scrollController.position.maxScrollExtent * 0.8) {
      _loadMoreSeries();
    }
  }

  void _onSearchChanged(String query) {
    _searchDebounce?.cancel();
    setState(() {
      _searchQuery = query;
      if (query.isEmpty) {
        _searchResults = null;
        _isSearching = false;
      }
    });

    if (query.length >= 2) {
      _searchDebounce = Timer(const Duration(milliseconds: 500), () {
        _performSearch(query);
      });
    }
  }

  Future<void> _performSearch(String query) async {
    if (query.isEmpty) return;
    setState(() => _isSearching = true);

    try {
      final service = ref.read(xtreamServiceProvider(widget.playlist));
      final results = await service.searchSeries(query);

      if (mounted && _searchQuery == query) {
        setState(() {
          _searchResults = results;
          _isSearching = false;
        });
      }
    } catch (e) {
      if (mounted) setState(() => _isSearching = false);
    }
  }

  Future<void> _loadMoreSeries() async {
    if (_isLoading || !_hasMore || !mounted) return;

    setState(() => _isLoading = true);

    try {
      final service = ref.read(xtreamServiceProvider(widget.playlist));
      final newSeries = await service.getSeriesPaginated(
        offset: _currentOffset,
        limit: _pageSize,
      );

      if (mounted) {
        setState(() {
          _series.addAll(newSeries);
          _currentOffset += _pageSize;
          _hasMore = newSeries.length == _pageSize;
          _isLoading = false;
        });
      }
    } catch (e) {
      if (mounted) {
        setState(() => _isLoading = false);
      }
    }
  }

  String? _formatRating(String? rating) {
    if (rating == null || rating.isEmpty) return null;
    final value = double.tryParse(rating);
    if (value != null) {
      return value.toStringAsFixed(1);
    }
    return rating;
  }

  String _getProxiedImageUrl(String? originalUrl, WidgetRef ref) {
    if (originalUrl == null || originalUrl.isEmpty) return '';
    if (originalUrl.startsWith('http')) {
      final service = ref.read(xtreamServiceProvider(widget.playlist));
      return '${service.backendBaseUrl}/api/xtream/$originalUrl';
    }
    return originalUrl;
  }

  void _openSeries(Series series) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => MobileSeriesDetailScreen(
          series: series,
          playlist: widget.playlist,
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    final settings = ref.watch(iptvSettingsProvider);

    List<Series> displaySeries;
    if (_searchQuery.isNotEmpty && _searchResults != null) {
      displaySeries = _searchResults!;
    } else {
      displaySeries = settings.seriesKeywords.isEmpty
          ? _series
          : _series
              .where((s) => settings.matchesSeriesFilter(s.categoryName))
              .toList();
    }

    final heroItems = displaySeries
        .take(3)
        .map(
          (s) => HeroItem(
            id: s.seriesId.toString(),
            title: s.name,
            imageUrl: _getProxiedImageUrl(s.cover, ref),
            subtitle: s.rating != null ? '${_formatRating(s.rating)} ★' : null,
            onMoreInfo: () => _openSeries(s),
          ),
        )
        .toList();

    return SafeArea(
      bottom: false,
      child: CustomScrollView(
        controller: _scrollController,
        slivers: [
          // Glass Header & Search
          SliverToBoxAdapter(
            child: Padding(
              padding: const EdgeInsets.all(16),
              child: GlassContainer.glass(
                borderRadius: 100,
                padding:
                    const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
                child: Row(
                  children: [
                    const Icon(Icons.search, size: 20, color: AppColors.onSurfaceVariant),
                    const SizedBox(width: 8),
                    Expanded(
                      child: TextField(
                        controller: _searchController,
                        style: GoogleFonts.instrumentSans(
                          fontSize: 14,
                          color: AppColors.onSurface,
                        ),
                        decoration: InputDecoration(
                          hintText: 'Search Series...',
                          hintStyle: GoogleFonts.instrumentSans(color: AppColors.onSurfaceVariant),
                          border: InputBorder.none,
                          isDense: true,
                          contentPadding: const EdgeInsets.only(bottom: 11),
                        ),
                        onChanged: _onSearchChanged,
                      ),
                    ),
                    if (_isSearching)
                      const SizedBox(
                        width: 12,
                        height: 12,
                        child: CircularProgressIndicator(
                          strokeWidth: 2,
                          color: AppColors.onSurface,
                        ),
                      ),
                    if (_searchQuery.isNotEmpty)
                      GestureDetector(
                        onTap: () {
                          _searchController.clear();
                          _onSearchChanged('');
                        },
                        child: const Icon(
                          Icons.close,
                          size: 16,
                          color: AppColors.onSurface,
                        ),
                      ),
                  ],
                ),
              ),
            ),
          ),

          // Hero Section
          if (_searchQuery.isEmpty && heroItems.isNotEmpty)
            SliverToBoxAdapter(
              child: Padding(
                padding: const EdgeInsets.only(bottom: 24),
                child: SizedBox(
                  height: 250,
                  child: HeroCarousel(
                    items: heroItems,
                    onTap: (item) {
                      try {
                        final series = _series.firstWhere(
                          (s) => s.seriesId.toString() == item.id,
                        );
                        _openSeries(series);
                      } catch (e) {
                        // Fallback
                      }
                    },
                  ),
                ),
              ),
            ),

          // Grid
          SliverPadding(
            padding: const EdgeInsets.fromLTRB(16, 0, 16, 80),
            sliver: SliverGrid(
              gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
                crossAxisCount: 2,
                crossAxisSpacing: 12,
                mainAxisSpacing: 16,
                childAspectRatio: 0.65,
              ),
              delegate: SliverChildBuilderDelegate(
                (context, index) {
                  if (index >= displaySeries.length) return null;
                  final series = displaySeries[index];

                  return GestureDetector(
                    onTap: () => _openSeries(series),
                    child: Stack(
                      fit: StackFit.expand,
                      children: [
                        // Poster
                        ClipRRect(
                          borderRadius: BorderRadius.circular(16),
                          child:
                              series.cover != null && series.cover!.isNotEmpty
                                  ? Image.network(
                                      _getProxiedImageUrl(series.cover, ref),
                                      fit: BoxFit.cover,
                                      errorBuilder: (_, __, ___) =>
                                          Container(color: AppColors.surfaceContainerLow),
                                    )
                                  : Container(
                                      color: AppColors.surfaceContainerLow,
                                      child: const Icon(
                                        Icons.tv,
                                        color: AppColors.outlineVariant,
                                      ),
                                    ),
                        ),

                        // Gradient Overlay
                        Positioned(
                          bottom: 0,
                          left: 0,
                          right: 0,
                          height: 80,
                          child: Container(
                            decoration: BoxDecoration(
                              gradient: LinearGradient(
                                begin: Alignment.topCenter,
                                end: Alignment.bottomCenter,
                                colors: [
                                  Colors.transparent,
                                  AppColors.background.withOpacity(0.9),
                                ],
                              ),
                              borderRadius: const BorderRadius.vertical(
                                bottom: Radius.circular(16),
                              ),
                            ),
                          ),
                        ),

                        // Title
                        Positioned(
                          bottom: 12,
                          left: 12,
                          right: 12,
                          child: Text(
                            series.name,
                            style: GoogleFonts.instrumentSans(
                              color: AppColors.onSurface,
                              fontSize: 13,
                              fontWeight: FontWeight.w600,
                            ),
                            maxLines: 2,
                            overflow: TextOverflow.ellipsis,
                          ),
                        ),

                        // Rating
                        if (series.rating != null && series.rating!.isNotEmpty)
                          Positioned(
                            top: 8,
                            right: 8,
                            child: GlassContainer.glass(
                              borderRadius: 4,
                              padding: const EdgeInsets.symmetric(
                                horizontal: 6,
                                vertical: 2,
                              ),
                              child: Row(
                                mainAxisSize: MainAxisSize.min,
                                children: [
                                  const Icon(
                                    Icons.star,
                                    size: 10,
                                    color: Colors.amber,
                                  ),
                                  const SizedBox(width: 4),
                                  Text(
                                    _formatRating(series.rating)!,
                                    style: GoogleFonts.instrumentSans(
                                      fontSize: 10,
                                      fontWeight: FontWeight.bold,
                                      color: AppColors.onSurface,
                                    ),
                                  ),
                                ],
                              ),
                            ),
                          ),
                      ],
                    ),
                  );
                },
                childCount: displaySeries.length,
              ),
            ),
          ),

          if (_isLoading)
            const SliverToBoxAdapter(
              child: Padding(
                padding: EdgeInsets.all(24),
                child: Center(
                  child: CircularProgressIndicator(color: AppColors.onSurface),
                ),
              ),
            ),
        ],
      ),
    );
  }
}