import 'dart:typed_data';
import 'package:flutter/material.dart';
import '../../core/service_locator.dart';
import '../../core/logger.dart';
import '../../data/recipes/recipe_service.dart';
import '../../data/recipes/models/bookmark_category_model.dart';
import '../../data/recipes/models/recipe_model.dart';
import '../add_recipe/add_recipe_screen.dart';
import '../photo_gallery/photo_gallery_screen.dart';
import 'bookmark_category_recipes_screen.dart';

/// Bookmarks screen displaying all bookmark categories and their recipes.
class BookmarksScreen extends StatefulWidget {
  const BookmarksScreen({super.key});

  @override
  State<BookmarksScreen> createState() => _BookmarksScreenState();
}

class _BookmarksScreenState extends State<BookmarksScreen> {
  List<BookmarkCategory> _categories = [];
  Map<String, List<RecipeModel>> _recipesByCategory = {};
  bool _isLoading = false;
  String? _errorMessage;
  RecipeService? _recipeService;
  bool _wasLoggedIn = false;
  String _searchQuery = '';
  final TextEditingController _searchController = TextEditingController();

  @override
  void initState() {
    super.initState();
    _checkLoginState();
    _initializeService();
    _searchController.addListener(() {
      setState(() {
        _searchQuery = _searchController.text.toLowerCase();
      });
    });
  }

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

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    _checkLoginState();
    if (_recipeService != null && _wasLoggedIn) {
      _loadBookmarks();
    }
  }

  @override
  void didUpdateWidget(BookmarksScreen oldWidget) {
    super.didUpdateWidget(oldWidget);
    _checkLoginState();
    if (_recipeService != null && _wasLoggedIn) {
      _loadBookmarks();
    }
  }

  void _checkLoginState() {
    final sessionService = ServiceLocator.instance.sessionService;
    final isLoggedIn = sessionService?.isLoggedIn ?? false;
    
    if (isLoggedIn != _wasLoggedIn) {
      _wasLoggedIn = isLoggedIn;
      if (mounted) {
        setState(() {});
        if (isLoggedIn && _recipeService != null) {
          _loadBookmarks();
        }
      }
    }
  }

  Future<void> _initializeService() async {
    try {
      _recipeService = ServiceLocator.instance.recipeService;
      if (_recipeService == null) {
        throw Exception('RecipeService not available in ServiceLocator');
      }
    } catch (e) {
      Logger.error('Failed to initialize RecipeService', e);
      if (mounted) {
        setState(() {
          _errorMessage = 'Failed to initialize recipe service: $e';
        });
      }
    }
  }

  Future<void> _loadBookmarks() async {
    if (_recipeService == null) return;

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

    try {
      final categories = await _recipeService!.getAllBookmarkCategories();
      final recipesMap = <String, List<RecipeModel>>{};
      
      for (final category in categories) {
        final recipes = await _recipeService!.getRecipesByCategory(category.id);
        recipesMap[category.id] = recipes;
      }
      
      if (mounted) {
        setState(() {
          _categories = categories;
          _recipesByCategory = recipesMap;
          _isLoading = false;
        });
      }
    } catch (e) {
      Logger.error('Failed to load bookmarks', e);
      if (mounted) {
        setState(() {
          _isLoading = false;
          _errorMessage = 'Failed to load bookmarks: $e';
        });
      }
    }
  }

  Color _parseColor(String hexColor) {
    try {
      return Color(int.parse(hexColor.replaceAll('#', '0xFF')));
    } catch (e) {
      return Colors.blue;
    }
  }

  List<BookmarkCategory> _getFilteredCategories() {
    if (_searchQuery.isEmpty) {
      return _categories;
    }
    return _categories.where((category) {
      final recipes = _recipesByCategory[category.id] ?? [];
      return category.name.toLowerCase().contains(_searchQuery) ||
          recipes.any((recipe) =>
              recipe.title.toLowerCase().contains(_searchQuery) ||
              (recipe.description?.toLowerCase().contains(_searchQuery) ?? false));
    }).toList();
  }

  List<RecipeModel> _getFilteredRecipes(String categoryId) {
    final recipes = _recipesByCategory[categoryId] ?? [];
    if (_searchQuery.isEmpty) {
      return recipes;
    }
    return recipes.where((recipe) =>
        recipe.title.toLowerCase().contains(_searchQuery) ||
        (recipe.description?.toLowerCase().contains(_searchQuery) ?? false)).toList();
  }

  void _viewRecipe(RecipeModel recipe) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => AddRecipeScreen(
          recipe: recipe,
          viewMode: true,
        ),
      ),
    ).then((_) {
      // Reload bookmarks when returning from recipe view
      _loadBookmarks();
    });
  }

  void _openCategory(BookmarkCategory category) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => BookmarkCategoryRecipesScreen(
          category: category,
        ),
      ),
    ).then((_) {
      // Reload bookmarks when returning from category view
      _loadBookmarks();
    });
  }

  Future<void> _deleteCategory(BookmarkCategory category) async {
    final recipes = _recipesByCategory[category.id] ?? [];
    final recipeCount = recipes.length;
    
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('Delete Bookmark Category'),
        content: Text(
          recipeCount > 0
              ? 'Are you sure you want to delete "${category.name}"? This will remove this bookmark from all $recipeCount recipe${recipeCount != 1 ? 's' : ''} that have it.'
              : 'Are you sure you want to delete "${category.name}"?',
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.of(context).pop(false),
            child: const Text('Cancel'),
          ),
          TextButton(
            onPressed: () => Navigator.of(context).pop(true),
            style: TextButton.styleFrom(
              foregroundColor: Colors.red,
            ),
            child: const Text('Delete'),
          ),
        ],
      ),
    );

    if (confirmed == true && _recipeService != null) {
      try {
        await _recipeService!.deleteBookmarkCategory(category.id);
        if (mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(
              content: Text(
                recipeCount > 0
                    ? 'Bookmark removed from $recipeCount recipe${recipeCount != 1 ? 's' : ''}'
                    : 'Bookmark category deleted',
              ),
              backgroundColor: Colors.green,
            ),
          );
          // Reload bookmarks to reflect the deletion
          _loadBookmarks();
        }
      } catch (e) {
        Logger.error('Failed to delete bookmark category', e);
        if (mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(
              content: Text('Failed to delete bookmark category: $e'),
              backgroundColor: Colors.red,
            ),
          );
        }
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    final isLoggedIn = ServiceLocator.instance.sessionService?.isLoggedIn ?? false;

    if (!isLoggedIn) {
      return Scaffold(
        appBar: AppBar(title: const Text('Bookmarks')),
        body: Center(
          child: Padding(
            padding: const EdgeInsets.all(24),
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Icon(
                  Icons.bookmark_border,
                  size: 80,
                  color: Colors.grey.shade400,
                ),
                const SizedBox(height: 24),
                Text(
                  'Please log in to view bookmarks',
                  style: Theme.of(context).textTheme.titleLarge?.copyWith(
                    color: Colors.grey.shade700,
                  ),
                  textAlign: TextAlign.center,
                ),
                const SizedBox(height: 8),
                Text(
                  'Sign in to save and organize your favorite recipes',
                  style: Theme.of(context).textTheme.bodyMedium?.copyWith(
                    color: Colors.grey.shade600,
                  ),
                  textAlign: TextAlign.center,
                ),
              ],
            ),
          ),
        ),
      );
    }

    if (_isLoading) {
      return Scaffold(
        appBar: AppBar(title: const Text('Bookmarks')),
        body: const Center(child: CircularProgressIndicator()),
      );
    }

    if (_errorMessage != null) {
      return Scaffold(
        appBar: AppBar(title: const Text('Bookmarks')),
        body: Center(
          child: Padding(
            padding: const EdgeInsets.all(24),
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Icon(
                  Icons.error_outline,
                  size: 64,
                  color: Colors.red.shade300,
                ),
                const SizedBox(height: 16),
                Text(
                  'Oops! Something went wrong',
                  style: Theme.of(context).textTheme.titleLarge,
                  textAlign: TextAlign.center,
                ),
                const SizedBox(height: 8),
                Text(
                  _errorMessage!,
                  style: Theme.of(context).textTheme.bodyMedium?.copyWith(
                    color: Colors.grey.shade600,
                  ),
                  textAlign: TextAlign.center,
                ),
                const SizedBox(height: 24),
                ElevatedButton.icon(
                  onPressed: _loadBookmarks,
                  icon: const Icon(Icons.refresh),
                  label: const Text('Retry'),
                  style: ElevatedButton.styleFrom(
                    padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12),
                  ),
                ),
              ],
            ),
          ),
        ),
      );
    }

    if (_categories.isEmpty) {
      return Scaffold(
        appBar: AppBar(title: const Text('Bookmarks')),
        body: Center(
          child: Padding(
            padding: const EdgeInsets.all(24),
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Icon(
                  Icons.bookmark_add_outlined,
                  size: 100,
                  color: Colors.grey.shade300,
                ),
                const SizedBox(height: 24),
                Text(
                  'No bookmark categories yet',
                  style: Theme.of(context).textTheme.headlineSmall?.copyWith(
                    fontWeight: FontWeight.bold,
                    color: Colors.grey.shade700,
                  ),
                  textAlign: TextAlign.center,
                ),
                const SizedBox(height: 12),
                Text(
                  'Bookmark a recipe to organize your favorites into categories',
                  style: Theme.of(context).textTheme.bodyLarge?.copyWith(
                    color: Colors.grey.shade600,
                  ),
                  textAlign: TextAlign.center,
                ),
              ],
            ),
          ),
        ),
      );
    }

    final filteredCategories = _getFilteredCategories();

    return Scaffold(
      appBar: AppBar(
        title: const Text('Bookmarks'),
        elevation: 0,
      ),
      body: RefreshIndicator(
        onRefresh: _loadBookmarks,
        child: CustomScrollView(
          slivers: [
            // Search bar
            SliverToBoxAdapter(
              child: Padding(
                padding: const EdgeInsets.fromLTRB(16, 16, 16, 8),
                child: TextField(
                  controller: _searchController,
                  decoration: InputDecoration(
                    hintText: 'Search bookmarks...',
                    prefixIcon: const Icon(Icons.search),
                    suffixIcon: _searchQuery.isNotEmpty
                        ? IconButton(
                            icon: const Icon(Icons.clear),
                            onPressed: () {
                              _searchController.clear();
                            },
                          )
                        : null,
                    filled: true,
                    fillColor: Theme.of(context).brightness == Brightness.dark
                        ? Colors.grey[800]
                        : Colors.grey[100],
                    border: OutlineInputBorder(
                      borderRadius: BorderRadius.circular(12),
                      borderSide: BorderSide.none,
                    ),
                    contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
                  ),
                ),
              ),
            ),
            // Categories list
            if (filteredCategories.isEmpty && _searchQuery.isNotEmpty)
              SliverFillRemaining(
                hasScrollBody: false,
                child: Center(
                  child: Padding(
                    padding: const EdgeInsets.all(24),
                    child: Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: [
                        Icon(
                          Icons.search_off,
                          size: 64,
                          color: Colors.grey.shade400,
                        ),
                        const SizedBox(height: 16),
                        Text(
                          'No results found',
                          style: Theme.of(context).textTheme.titleLarge?.copyWith(
                            color: Colors.grey.shade700,
                          ),
                        ),
                        const SizedBox(height: 8),
                        Text(
                          'Try a different search term',
                          style: Theme.of(context).textTheme.bodyMedium?.copyWith(
                            color: Colors.grey.shade600,
                          ),
                        ),
                      ],
                    ),
                  ),
                ),
              )
            else
              SliverPadding(
                padding: const EdgeInsets.all(16),
                sliver: SliverList(
                  delegate: SliverChildBuilderDelegate(
                    (context, index) {
                      final category = filteredCategories[index];
                      final recipes = _getFilteredRecipes(category.id);
                      
                      return _CategoryCard(
                        category: category,
                        recipes: recipes,
                        categoryColor: category.color != null
                            ? _parseColor(category.color!)
                            : Theme.of(context).primaryColor,
                        onTap: () => _openCategory(category),
                        onDelete: () => _deleteCategory(category),
                      );
                    },
                    childCount: filteredCategories.length,
                  ),
                ),
              ),
          ],
        ),
      ),
    );
  }
}

/// Modern category card widget
class _CategoryCard extends StatelessWidget {
  final BookmarkCategory category;
  final List<RecipeModel> recipes;
  final Color categoryColor;
  final VoidCallback onTap;
  final VoidCallback onDelete;

  const _CategoryCard({
    required this.category,
    required this.recipes,
    required this.categoryColor,
    required this.onTap,
    required this.onDelete,
  });

  @override
  Widget build(BuildContext context) {
    return Card(
      margin: const EdgeInsets.only(bottom: 16),
      elevation: 2,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(16),
      ),
      child: InkWell(
        onTap: onTap,
        borderRadius: BorderRadius.circular(16),
        child: Padding(
          padding: const EdgeInsets.all(16),
          child: Row(
            children: [
              // Category icon/color indicator
              Container(
                width: 48,
                height: 48,
                decoration: BoxDecoration(
                  color: categoryColor.withOpacity(0.2),
                  borderRadius: BorderRadius.circular(12),
                  border: Border.all(
                    color: categoryColor,
                    width: 2,
                  ),
                ),
                child: Icon(
                  Icons.bookmark,
                  color: categoryColor,
                  size: 24,
                ),
              ),
              const SizedBox(width: 16),
              // Category info
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      category.name,
                      style: Theme.of(context).textTheme.titleLarge?.copyWith(
                        fontWeight: FontWeight.bold,
                      ),
                    ),
                    const SizedBox(height: 4),
                    Row(
                      children: [
                        Icon(
                          Icons.restaurant_menu,
                          size: 16,
                          color: Colors.grey.shade600,
                        ),
                        const SizedBox(width: 4),
                        Text(
                          '${recipes.length} recipe${recipes.length != 1 ? 's' : ''}',
                          style: Theme.of(context).textTheme.bodyMedium?.copyWith(
                            color: Colors.grey.shade600,
                          ),
                        ),
                      ],
                    ),
                  ],
                ),
              ),
              // Delete button
              IconButton(
                icon: const Icon(Icons.delete_outline),
                color: Colors.red.shade400,
                onPressed: onDelete,
                tooltip: 'Delete bookmark category',
                padding: EdgeInsets.zero,
                constraints: const BoxConstraints(),
              ),
              const SizedBox(width: 8),
              // Chevron icon
              Icon(
                Icons.chevron_right,
                color: Colors.grey.shade600,
              ),
            ],
          ),
        ),
      ),
    );
  }
}

/// Widget for displaying a recipe item in a bookmark category.
class _BookmarkRecipeItem extends StatelessWidget {
  final RecipeModel recipe;
  final VoidCallback onTap;
  final ValueChanged<int> onPhotoTap;

  const _BookmarkRecipeItem({
    required this.recipe,
    required this.onTap,
    required this.onPhotoTap,
  });

  /// Builds an image widget using ImmichService for authenticated access.
  Widget _buildRecipeImage(String imageUrl) {
    final mediaService = ServiceLocator.instance.mediaService;
    if (mediaService == null) {
      return Container(
        width: 60,
        height: 60,
        color: Colors.grey.shade200,
        child: const Icon(Icons.image, size: 32),
      );
    }
    
    // Try to extract asset ID from Immich URL (format: .../api/assets/{id}/original)
    final assetIdMatch = RegExp(r'/api/assets/([^/]+)/').firstMatch(imageUrl);
    String? assetId;
    
    if (assetIdMatch != null) {
      assetId = assetIdMatch.group(1);
    } else {
      // For Blossom URLs, use the full URL
      assetId = imageUrl;
    }
    
    if (assetId != null) {
      return FutureBuilder<Uint8List?>(
        future: mediaService.fetchImageBytes(assetId, isThumbnail: true),
          builder: (context, snapshot) {
            if (snapshot.connectionState == ConnectionState.waiting) {
              return Container(
                color: Colors.grey.shade200,
                child: const Center(
                  child: CircularProgressIndicator(),
                ),
              );
            }

            if (snapshot.hasError || !snapshot.hasData || snapshot.data == null) {
              return Container(
                color: Colors.grey.shade200,
                child: const Icon(Icons.broken_image, size: 32),
              );
            }

            return Image.memory(
              snapshot.data!,
              fit: BoxFit.cover,
              width: double.infinity,
              height: double.infinity,
            );
          },
        );
    }
    
    return Image.network(
      imageUrl,
      fit: BoxFit.cover,
      width: double.infinity,
      height: double.infinity,
      errorBuilder: (context, error, stackTrace) {
        return Container(
          color: Colors.grey.shade200,
          child: const Icon(Icons.broken_image, size: 32),
        );
      },
      loadingBuilder: (context, child, loadingProgress) {
        if (loadingProgress == null) return child;
        return Container(
          color: Colors.grey.shade200,
          child: Center(
            child: CircularProgressIndicator(
              value: loadingProgress.expectedTotalBytes != null
                  ? loadingProgress.cumulativeBytesLoaded /
                      loadingProgress.expectedTotalBytes!
                  : null,
            ),
          ),
        );
      },
    );
  }

  Color _getRatingColor(double rating) {
    if (rating >= 4.5) return Colors.green;
    if (rating >= 3.5) return Colors.orange;
    if (rating >= 2.5) return Colors.amber;
    return Colors.red;
  }

  @override
  Widget build(BuildContext context) {
    return InkWell(
      onTap: onTap,
      child: Padding(
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
        child: Row(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            // Recipe image
            recipe.imageUrls.isNotEmpty
                ? GestureDetector(
                    onTap: () => onPhotoTap(0),
                    child: ClipRRect(
                      borderRadius: BorderRadius.circular(12),
                      child: Container(
                        width: 80,
                        height: 80,
                        decoration: BoxDecoration(
                          color: Colors.grey.shade200,
                          borderRadius: BorderRadius.circular(12),
                        ),
                        child: _buildRecipeImage(recipe.imageUrls.first),
                      ),
                    ),
                  )
                : Container(
                    width: 80,
                    height: 80,
                    decoration: BoxDecoration(
                      color: Colors.grey.shade200,
                      borderRadius: BorderRadius.circular(12),
                    ),
                    child: Icon(
                      Icons.restaurant_menu,
                      color: Colors.grey.shade400,
                      size: 32,
                    ),
                  ),
            const SizedBox(width: 16),
            // Recipe info
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Text(
                    recipe.title,
                    style: Theme.of(context).textTheme.titleMedium?.copyWith(
                      fontWeight: FontWeight.w600,
                    ),
                    maxLines: 2,
                    overflow: TextOverflow.ellipsis,
                  ),
                  if (recipe.description != null && recipe.description!.isNotEmpty) ...[
                    const SizedBox(height: 6),
                    Text(
                      recipe.description!,
                      style: Theme.of(context).textTheme.bodySmall?.copyWith(
                        color: Colors.grey.shade600,
                      ),
                      maxLines: 2,
                      overflow: TextOverflow.ellipsis,
                    ),
                  ],
                  const SizedBox(height: 8),
                  Row(
                    children: [
                      // Rating badge
                      Container(
                        padding: const EdgeInsets.symmetric(
                          horizontal: 8,
                          vertical: 4,
                        ),
                        decoration: BoxDecoration(
                          color: _getRatingColor(recipe.rating.toDouble()).withOpacity(0.15),
                          borderRadius: BorderRadius.circular(12),
                        ),
                        child: Row(
                          mainAxisSize: MainAxisSize.min,
                          children: [
                            const Icon(
                              Icons.star,
                              size: 14,
                              color: Colors.amber,
                            ),
                            const SizedBox(width: 4),
                            Text(
                              recipe.rating.toString(),
                              style: Theme.of(context).textTheme.labelSmall?.copyWith(
                                fontWeight: FontWeight.bold,
                                color: _getRatingColor(recipe.rating.toDouble()),
                              ),
                            ),
                          ],
                        ),
                      ),
                      if (recipe.isFavourite) ...[
                        const SizedBox(width: 8),
                        Icon(
                          Icons.favorite,
                          size: 16,
                          color: Colors.red.shade400,
                        ),
                      ],
                    ],
                  ),
                ],
              ),
            ),
            // Chevron icon
            Icon(
              Icons.chevron_right,
              color: Colors.grey.shade400,
            ),
          ],
        ),
      ),
    );
  }
}