import 'dart:async';
import 'package:flutter/material.dart';
import 'package:gwid/api/api_service.dart';
import 'package:gwid/models/channel.dart';

class SearchChannelsScreen extends StatefulWidget {
  const SearchChannelsScreen({super.key});

  @override
  State<SearchChannelsScreen> createState() => _SearchChannelsScreenState();
}

class _SearchChannelsScreenState extends State<SearchChannelsScreen> {
  final TextEditingController _searchController = TextEditingController();
  StreamSubscription? _apiSubscription;
  bool _isLoading = false;
  List<Channel> _foundChannels = [];
  String? _errorMessage;

  @override
  void initState() {
    super.initState();
    _listenToApiMessages();
  }

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

  void _listenToApiMessages() {
    _apiSubscription = ApiService.instance.messages.listen((message) {
      if (!mounted) return;


      if (message['type'] == 'channels_found') {
        setState(() {
          _isLoading = false;
          _errorMessage = null;
        });

        final payload = message['payload'];
        final channelsData = payload['contacts'] as List<dynamic>?;

        if (channelsData != null) {
          _foundChannels = channelsData
              .map((channelJson) => Channel.fromJson(channelJson))
              .toList();
        }

        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('Найдено каналов: ${_foundChannels.length}'),
            backgroundColor: Colors.green,
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(12),
            ),
            behavior: SnackBarBehavior.floating,
            margin: const EdgeInsets.all(10),
          ),
        );
      }


      if (message['type'] == 'channels_not_found') {
        setState(() {
          _isLoading = false;
          _foundChannels.clear();
        });

        final payload = message['payload'];
        String errorMessage = 'Каналы не найдены';

        if (payload != null) {
          if (payload['localizedMessage'] != null) {
            errorMessage = payload['localizedMessage'];
          } else if (payload['message'] != null) {
            errorMessage = payload['message'];
          }
        }

        setState(() {
          _errorMessage = errorMessage;
        });

        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text(errorMessage),
            backgroundColor: Colors.orange,
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(12),
            ),
            behavior: SnackBarBehavior.floating,
            margin: const EdgeInsets.all(10),
          ),
        );
      }
    });
  }

  void _searchChannels() async {
    final searchQuery = _searchController.text.trim();

    if (searchQuery.isEmpty) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: const Text('Введите поисковый запрос'),
          backgroundColor: Colors.orange,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(12),
          ),
          behavior: SnackBarBehavior.floating,
          margin: const EdgeInsets.all(10),
        ),
      );
      return;
    }

    setState(() {
      _isLoading = true;
      _foundChannels.clear();
      _errorMessage = null;
    });

    try {
      await ApiService.instance.searchChannels(searchQuery);
    } catch (e) {
      setState(() {
        _isLoading = false;
      });
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text('Ошибка поиска каналов: ${e.toString()}'),
          backgroundColor: Theme.of(context).colorScheme.error,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(12),
          ),
          behavior: SnackBarBehavior.floating,
          margin: const EdgeInsets.all(10),
        ),
      );
    }
  }

  void _viewChannel(Channel channel) {
    Navigator.of(context).push(
      MaterialPageRoute(
        builder: (context) => ChannelDetailsScreen(channel: channel),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;

    return Scaffold(
      appBar: AppBar(
        title: const Text('Поиск каналов'),
        backgroundColor: colors.surface,
        foregroundColor: colors.onSurface,
      ),
      body: Stack(
        children: [
          SingleChildScrollView(
            padding: const EdgeInsets.all(20.0),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [

                Container(
                  padding: const EdgeInsets.all(16),
                  decoration: BoxDecoration(
                    color: colors.primaryContainer.withOpacity(0.3),
                    borderRadius: BorderRadius.circular(12),
                  ),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Row(
                        children: [
                          Icon(
                            Icons.broadcast_on_personal,
                            color: colors.primary,
                          ),
                          const SizedBox(width: 8),
                          Text(
                            'Поиск каналов',
                            style: TextStyle(
                              fontWeight: FontWeight.bold,
                              color: colors.primary,
                            ),
                          ),
                        ],
                      ),
                      const SizedBox(height: 8),
                      Text(
                        'Найдите интересные каналы по названию или описанию. '
                        'Вы можете просматривать каналы и подписываться на них.',
                        style: TextStyle(color: colors.onSurfaceVariant),
                      ),
                    ],
                  ),
                ),

                const SizedBox(height: 24),


                Text(
                  'Поисковый запрос',
                  style: Theme.of(
                    context,
                  ).textTheme.titleLarge?.copyWith(fontWeight: FontWeight.bold),
                ),
                const SizedBox(height: 16),

                TextField(
                  controller: _searchController,
                  decoration: InputDecoration(
                    labelText: 'Название или описание канала',
                    hintText: 'Например: новости, технологии, развлечения',
                    border: OutlineInputBorder(
                      borderRadius: BorderRadius.circular(12),
                    ),
                    prefixIcon: const Icon(Icons.search),
                  ),
                ),
                const SizedBox(height: 8),
                Container(
                  padding: const EdgeInsets.all(12),
                  decoration: BoxDecoration(
                    color: colors.surfaceContainerHighest,
                    borderRadius: BorderRadius.circular(8),
                    border: Border.all(color: colors.outline.withOpacity(0.3)),
                  ),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Row(
                        children: [
                          Icon(
                            Icons.info_outline,
                            size: 16,
                            color: colors.primary,
                          ),
                          const SizedBox(width: 8),
                          Text(
                            'Советы по поиску:',
                            style: TextStyle(
                              fontWeight: FontWeight.w600,
                              color: colors.primary,
                              fontSize: 14,
                            ),
                          ),
                        ],
                      ),
                      const SizedBox(height: 8),
                      Text(
                        '• Используйте ключевые слова\n'
                        '• Поиск по названию или описанию\n'
                        '• Попробуйте разные варианты написания',
                        style: TextStyle(
                          color: colors.onSurfaceVariant,
                          fontSize: 13,
                          height: 1.4,
                        ),
                      ),
                    ],
                  ),
                ),
                const SizedBox(height: 24),

                SizedBox(
                  width: double.infinity,
                  child: ElevatedButton.icon(
                    onPressed: _isLoading ? null : _searchChannels,
                    icon: _isLoading
                        ? SizedBox(
                            width: 20,
                            height: 20,
                            child: CircularProgressIndicator(
                              strokeWidth: 2,
                              valueColor: AlwaysStoppedAnimation<Color>(
                                colors.onPrimary,
                              ),
                            ),
                          )
                        : const Icon(Icons.search),
                    label: Text(_isLoading ? 'Поиск...' : 'Найти каналы'),
                    style: ElevatedButton.styleFrom(
                      minimumSize: const Size(double.infinity, 50),
                      shape: RoundedRectangleBorder(
                        borderRadius: BorderRadius.circular(12),
                      ),
                    ),
                  ),
                ),


                if (_foundChannels.isNotEmpty) ...[
                  const SizedBox(height: 24),
                  Text(
                    'Найденные каналы (${_foundChannels.length})',
                    style: Theme.of(context).textTheme.titleLarge?.copyWith(
                      fontWeight: FontWeight.bold,
                    ),
                  ),
                  const SizedBox(height: 16),
                  ..._foundChannels.map(
                    (channel) => _buildChannelCard(channel),
                  ),
                ],


                if (_errorMessage != null) ...[
                  const SizedBox(height: 24),
                  Container(
                    padding: const EdgeInsets.all(16),
                    decoration: BoxDecoration(
                      color: Colors.orange.withOpacity(0.1),
                      borderRadius: BorderRadius.circular(12),
                      border: Border.all(color: Colors.orange.withOpacity(0.3)),
                    ),
                    child: Row(
                      children: [
                        Icon(Icons.warning, color: Colors.orange),
                        const SizedBox(width: 8),
                        Expanded(
                          child: Text(
                            _errorMessage!,
                            style: TextStyle(
                              color: Colors.orange.shade800,
                              fontWeight: FontWeight.w500,
                            ),
                          ),
                        ),
                      ],
                    ),
                  ),
                ],
              ],
            ),
          ),
          if (_isLoading)
            Container(
              color: Colors.black.withOpacity(0.5),
              child: const Center(child: CircularProgressIndicator()),
            ),
        ],
      ),
    );
  }

  Widget _buildChannelCard(Channel channel) {
    final colors = Theme.of(context).colorScheme;

    return Card(
      margin: const EdgeInsets.only(bottom: 12),
      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
      child: ListTile(
        contentPadding: const EdgeInsets.all(16),
        leading: CircleAvatar(
          radius: 24,
          backgroundImage: channel.photoBaseUrl != null
              ? NetworkImage(channel.photoBaseUrl!)
              : null,
          child: channel.photoBaseUrl == null
              ? Text(
                  channel.name.isNotEmpty ? channel.name[0].toUpperCase() : '?',
                  style: TextStyle(
                    color: colors.onSurface,
                    fontWeight: FontWeight.w600,
                  ),
                )
              : null,
        ),
        title: Text(
          channel.name,
          style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 16),
        ),
        subtitle: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            if (channel.description?.isNotEmpty == true) ...[
              const SizedBox(height: 4),
              Text(
                channel.description!,
                style: TextStyle(color: colors.onSurfaceVariant, fontSize: 14),
                maxLines: 2,
                overflow: TextOverflow.ellipsis,
              ),
            ],
            const SizedBox(height: 8),
            Row(
              children: [
                if (channel.options.contains('BOT'))
                  Container(
                    padding: const EdgeInsets.symmetric(
                      horizontal: 8,
                      vertical: 2,
                    ),
                    decoration: BoxDecoration(
                      color: colors.primaryContainer,
                      borderRadius: BorderRadius.circular(12),
                    ),
                    child: Text(
                      'Бот',
                      style: TextStyle(
                        color: colors.onPrimaryContainer,
                        fontSize: 12,
                        fontWeight: FontWeight.w500,
                      ),
                    ),
                  ),
                if (channel.options.contains('HAS_WEBAPP')) ...[
                  const SizedBox(width: 8),
                  Container(
                    padding: const EdgeInsets.symmetric(
                      horizontal: 8,
                      vertical: 2,
                    ),
                    decoration: BoxDecoration(
                      color: colors.secondaryContainer,
                      borderRadius: BorderRadius.circular(12),
                    ),
                    child: Text(
                      'Веб-приложение',
                      style: TextStyle(
                        color: colors.onSecondaryContainer,
                        fontSize: 12,
                        fontWeight: FontWeight.w500,
                      ),
                    ),
                  ),
                ],
              ],
            ),
          ],
        ),
        trailing: Icon(
          Icons.arrow_forward_ios,
          size: 16,
          color: colors.onSurfaceVariant,
        ),
        onTap: () => _viewChannel(channel),
      ),
    );
  }
}

class ChannelDetailsScreen extends StatefulWidget {
  final Channel channel;

  const ChannelDetailsScreen({super.key, required this.channel});

  @override
  State<ChannelDetailsScreen> createState() => _ChannelDetailsScreenState();
}

class _ChannelDetailsScreenState extends State<ChannelDetailsScreen> {
  StreamSubscription? _apiSubscription;
  bool _isLoading = false;
  String? _webAppUrl;
  String? _errorMessage;

  @override
  void initState() {
    super.initState();
    _listenToApiMessages();
  }

  @override
  void dispose() {
    _apiSubscription?.cancel();
    super.dispose();
  }

  void _listenToApiMessages() {
    _apiSubscription = ApiService.instance.messages.listen((message) {
      if (!mounted) return;


      if (message['type'] == 'channel_entered') {
        setState(() {
          _isLoading = false;
          _errorMessage = null;
        });

        final payload = message['payload'];
        _webAppUrl = payload['url'] as String?;

        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: const Text('Канал открыт'),
            backgroundColor: Colors.green,
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(12),
            ),
            behavior: SnackBarBehavior.floating,
            margin: const EdgeInsets.all(10),
          ),
        );
      }


      if (message['type'] == 'channel_subscribed') {
        setState(() {
          _isLoading = false;
        });

        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: const Text('Подписка на канал успешна!'),
            backgroundColor: Colors.green,
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(12),
            ),
            behavior: SnackBarBehavior.floating,
            margin: const EdgeInsets.all(10),
          ),
        );
      }


      if (message['type'] == 'channel_error') {
        setState(() {
          _isLoading = false;
        });

        final payload = message['payload'];
        String errorMessage = 'Произошла ошибка';

        if (payload != null) {
          if (payload['localizedMessage'] != null) {
            errorMessage = payload['localizedMessage'];
          } else if (payload['message'] != null) {
            errorMessage = payload['message'];
          }
        }

        setState(() {
          _errorMessage = errorMessage;
        });

        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text(errorMessage),
            backgroundColor: Colors.red,
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(12),
            ),
            behavior: SnackBarBehavior.floating,
            margin: const EdgeInsets.all(10),
          ),
        );
      }
    });
  }


  String _extractChannelLink(String inputLink) {
    final link = inputLink.trim();


    if (link.startsWith('https://max.ru/') || link.startsWith('max.ru/')) {
      return link;
    }


    return link;
  }

  void _enterChannel() async {
    if (widget.channel.link == null) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: const Text('У канала нет ссылки для входа'),
          backgroundColor: Colors.orange,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(12),
          ),
          behavior: SnackBarBehavior.floating,
          margin: const EdgeInsets.all(10),
        ),
      );
      return;
    }

    setState(() {
      _isLoading = true;
      _errorMessage = null;
    });

    try {
      final processedLink = _extractChannelLink(widget.channel.link!);
      await ApiService.instance.enterChannel(processedLink);
    } catch (e) {
      setState(() {
        _isLoading = false;
      });
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text('Ошибка входа в канал: ${e.toString()}'),
          backgroundColor: Theme.of(context).colorScheme.error,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(12),
          ),
          behavior: SnackBarBehavior.floating,
          margin: const EdgeInsets.all(10),
        ),
      );
    }
  }

  void _subscribeToChannel() async {
    if (widget.channel.link == null) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: const Text('У канала нет ссылки для подписки'),
          backgroundColor: Colors.orange,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(12),
          ),
          behavior: SnackBarBehavior.floating,
          margin: const EdgeInsets.all(10),
        ),
      );
      return;
    }

    setState(() {
      _isLoading = true;
      _errorMessage = null;
    });

    try {
      final processedLink = _extractChannelLink(widget.channel.link!);
      await ApiService.instance.subscribeToChannel(processedLink);
    } catch (e) {
      setState(() {
        _isLoading = false;
      });
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text('Ошибка подписки на канал: ${e.toString()}'),
          backgroundColor: Theme.of(context).colorScheme.error,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(12),
          ),
          behavior: SnackBarBehavior.floating,
          margin: const EdgeInsets.all(10),
        ),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;

    return Scaffold(
      appBar: AppBar(
        title: const Text('Канал'),
        backgroundColor: colors.surface,
        foregroundColor: colors.onSurface,
      ),
      body: Stack(
        children: [
          SingleChildScrollView(
            padding: const EdgeInsets.all(20.0),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [

                Card(
                  shape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(16),
                  ),
                  child: Padding(
                    padding: const EdgeInsets.all(20),
                    child: Column(
                      children: [
                        CircleAvatar(
                          radius: 40,
                          backgroundImage: widget.channel.photoBaseUrl != null
                              ? NetworkImage(widget.channel.photoBaseUrl!)
                              : null,
                          child: widget.channel.photoBaseUrl == null
                              ? Text(
                                  widget.channel.name.isNotEmpty
                                      ? widget.channel.name[0].toUpperCase()
                                      : '?',
                                  style: TextStyle(
                                    color: colors.onSurface,
                                    fontWeight: FontWeight.w600,
                                    fontSize: 24,
                                  ),
                                )
                              : null,
                        ),
                        const SizedBox(height: 16),
                        Text(
                          widget.channel.name,
                          style: Theme.of(context).textTheme.headlineSmall
                              ?.copyWith(fontWeight: FontWeight.bold),
                          textAlign: TextAlign.center,
                        ),
                        if (widget.channel.description?.isNotEmpty == true) ...[
                          const SizedBox(height: 8),
                          Text(
                            widget.channel.description!,
                            style: TextStyle(
                              color: colors.onSurfaceVariant,
                              fontSize: 16,
                            ),
                            textAlign: TextAlign.center,
                          ),
                        ],
                        const SizedBox(height: 16),
                        Wrap(
                          spacing: 8,
                          runSpacing: 8,
                          children: [
                            if (widget.channel.options.contains('BOT'))
                              Container(
                                padding: const EdgeInsets.symmetric(
                                  horizontal: 12,
                                  vertical: 6,
                                ),
                                decoration: BoxDecoration(
                                  color: colors.primaryContainer,
                                  borderRadius: BorderRadius.circular(16),
                                ),
                                child: Text(
                                  'Бот',
                                  style: TextStyle(
                                    color: colors.onPrimaryContainer,
                                    fontSize: 14,
                                    fontWeight: FontWeight.w500,
                                  ),
                                ),
                              ),
                            if (widget.channel.options.contains('HAS_WEBAPP'))
                              Container(
                                padding: const EdgeInsets.symmetric(
                                  horizontal: 12,
                                  vertical: 6,
                                ),
                                decoration: BoxDecoration(
                                  color: colors.secondaryContainer,
                                  borderRadius: BorderRadius.circular(16),
                                ),
                                child: Text(
                                  'Веб-приложение',
                                  style: TextStyle(
                                    color: colors.onSecondaryContainer,
                                    fontSize: 14,
                                    fontWeight: FontWeight.w500,
                                  ),
                                ),
                              ),
                          ],
                        ),
                      ],
                    ),
                  ),
                ),

                const SizedBox(height: 24),


                Column(
                  children: [
                    SizedBox(
                      width: double.infinity,
                      child: ElevatedButton.icon(
                        onPressed: _isLoading ? null : _enterChannel,
                        icon: _isLoading
                            ? SizedBox(
                                width: 20,
                                height: 20,
                                child: CircularProgressIndicator(
                                  strokeWidth: 2,
                                  valueColor: AlwaysStoppedAnimation<Color>(
                                    colors.onPrimary,
                                  ),
                                ),
                              )
                            : const Icon(Icons.visibility),
                        label: Text(
                          _isLoading ? 'Загрузка...' : 'Просмотреть канал',
                        ),
                        style: ElevatedButton.styleFrom(
                          minimumSize: const Size(double.infinity, 50),
                          shape: RoundedRectangleBorder(
                            borderRadius: BorderRadius.circular(12),
                          ),
                        ),
                      ),
                    ),
                    const SizedBox(height: 12),
                    SizedBox(
                      width: double.infinity,
                      child: OutlinedButton.icon(
                        onPressed: _isLoading ? null : _subscribeToChannel,
                        icon: const Icon(Icons.subscriptions),
                        label: const Text('Подписаться на канал'),
                        style: OutlinedButton.styleFrom(
                          minimumSize: const Size(double.infinity, 50),
                          shape: RoundedRectangleBorder(
                            borderRadius: BorderRadius.circular(12),
                          ),
                        ),
                      ),
                    ),
                  ],
                ),


                if (_webAppUrl != null) ...[
                  const SizedBox(height: 24),
                  Container(
                    padding: const EdgeInsets.all(16),
                    decoration: BoxDecoration(
                      color: colors.primaryContainer.withOpacity(0.3),
                      borderRadius: BorderRadius.circular(12),
                      border: Border.all(
                        color: colors.primary.withOpacity(0.3),
                      ),
                    ),
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        Row(
                          children: [
                            Icon(Icons.web, color: colors.primary),
                            const SizedBox(width: 8),
                            Text(
                              'Веб-приложение канала',
                              style: TextStyle(
                                fontWeight: FontWeight.bold,
                                color: colors.primary,
                              ),
                            ),
                          ],
                        ),
                        const SizedBox(height: 8),
                        Text(
                          'Канал имеет веб-приложение. Вы можете открыть его в браузере.',
                          style: TextStyle(color: colors.onSurfaceVariant),
                        ),
                        const SizedBox(height: 12),
                        SizedBox(
                          width: double.infinity,
                          child: ElevatedButton.icon(
                            onPressed: () {

                              ScaffoldMessenger.of(context).showSnackBar(
                                SnackBar(
                                  content: const Text(
                                    'Открытие веб-приложения...',
                                  ),
                                  backgroundColor: Colors.blue,
                                  shape: RoundedRectangleBorder(
                                    borderRadius: BorderRadius.circular(12),
                                  ),
                                  behavior: SnackBarBehavior.floating,
                                  margin: const EdgeInsets.all(10),
                                ),
                              );
                            },
                            icon: const Icon(Icons.open_in_browser),
                            label: const Text('Открыть веб-приложение'),
                            style: ElevatedButton.styleFrom(
                              backgroundColor: colors.primary,
                              foregroundColor: colors.onPrimary,
                              shape: RoundedRectangleBorder(
                                borderRadius: BorderRadius.circular(12),
                              ),
                            ),
                          ),
                        ),
                      ],
                    ),
                  ),
                ],


                if (_errorMessage != null) ...[
                  const SizedBox(height: 24),
                  Container(
                    padding: const EdgeInsets.all(16),
                    decoration: BoxDecoration(
                      color: Colors.red.withOpacity(0.1),
                      borderRadius: BorderRadius.circular(12),
                      border: Border.all(color: Colors.red.withOpacity(0.3)),
                    ),
                    child: Row(
                      children: [
                        Icon(Icons.error, color: Colors.red),
                        const SizedBox(width: 8),
                        Expanded(
                          child: Text(
                            _errorMessage!,
                            style: TextStyle(
                              color: Colors.red.shade800,
                              fontWeight: FontWeight.w500,
                            ),
                          ),
                        ),
                      ],
                    ),
                  ),
                ],
              ],
            ),
          ),
          if (_isLoading)
            Container(
              color: Colors.black.withOpacity(0.5),
              child: const Center(child: CircularProgressIndicator()),
            ),
        ],
      ),
    );
  }
}