import 'package:auto_route/auto_route.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:line_icons/line_icons.dart';
import 'package:shimmer/shimmer.dart';

import '../../../application/category/category_loader/category_loader_bloc.dart';
import '../../../application/product/product_loader/product_loader_bloc.dart';
import '../../../common/theme/theme.dart';
import '../../../domain/category/category.dart';
import '../../../domain/product/product.dart';
import '../../../injection.dart';
import '../../components/appbar/appbar.dart';
import '../../components/button/button.dart';
import '../../components/widgets/empty_widget.dart';
import 'widgets/category_delegate.dart';
import 'widgets/product_card.dart';
import 'widgets/product_tile.dart';

@RoutePage()
class ProductPage extends StatefulWidget implements AutoRouteWrapper {
  const ProductPage({super.key});

  @override
  State<ProductPage> createState() => _ProductPageState();

  @override
  Widget wrappedRoute(BuildContext context) => MultiBlocProvider(
    providers: [
      BlocProvider(
        create: (context) =>
            getIt<CategoryLoaderBloc>()..add(CategoryLoaderEvent.fetched()),
      ),
      BlocProvider(
        create: (context) =>
            getIt<ProductLoaderBloc>()
              ..add(ProductLoaderEvent.fetched(isRefresh: true)),
      ),
    ],
    child: this,
  );
}

enum ViewType { grid, list }

class _ProductPageState extends State<ProductPage>
    with TickerProviderStateMixin {
  Category selectedCategory = Category.addAllData();
  ViewType currentViewType = ViewType.grid;
  ScrollController scrollController = ScrollController();

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

  @override
  Widget build(BuildContext context) {
    return BlocListener<ProductLoaderBloc, ProductLoaderState>(
      listenWhen: (previous, current) =>
          previous.categoryId != current.categoryId,
      listener: (context, state) {
        context.read<ProductLoaderBloc>().add(
          ProductLoaderEvent.fetched(isRefresh: true),
        );
      },
      child: BlocBuilder<ProductLoaderBloc, ProductLoaderState>(
        builder: (context, state) {
          return Scaffold(
            backgroundColor: AppColor.background,
            body: NotificationListener<ScrollNotification>(
              onNotification: (notification) {
                if (notification is ScrollEndNotification &&
                    scrollController.position.extentAfter == 0) {
                  context.read<ProductLoaderBloc>().add(
                    ProductLoaderEvent.fetched(),
                  );
                  return true;
                }

                return true;
              },
              child: CustomScrollView(
                controller: scrollController,
                slivers: [
                  _buildSliverAppBar(),
                  _buildCategoryFilter(),
                  _buildProductContent(state),
                ],
              ),
            ),
          );
        },
      ),
    );
  }

  Widget _buildSliverAppBar() {
    return SliverAppBar(
      expandedHeight: 120.0,
      floating: false,
      pinned: true,
      elevation: 0,
      flexibleSpace: CustomAppBar(title: 'Produk'),
      actions: [
        ActionIconButton(onTap: () {}, icon: LineIcons.search),
        ActionIconButton(
          onTap: _toggleViewType,
          icon: currentViewType == ViewType.grid
              ? LineIcons.list
              : LineIcons.thLarge,
        ),
      ],
    );
  }

  Widget _buildCategoryFilter() {
    return BlocBuilder<CategoryLoaderBloc, CategoryLoaderState>(
      builder: (context, state) {
        if (state.isFetching && state.categories.isEmpty) {
          return _buildCategoryShimmer();
        }

        return SliverPersistentHeader(
          pinned: true,
          delegate: ProductCategoryHeaderDelegate(
            categories: state.categories,
            selectedCategory: selectedCategory,
            onCategoryChanged: (category) {
              setState(() {
                selectedCategory = category;
              });
              if (category.id == Category.addAllData().id) {
                context.read<ProductLoaderBloc>().add(
                  ProductLoaderEvent.categoryIdChanged(''),
                );
              } else {
                context.read<ProductLoaderBloc>().add(
                  ProductLoaderEvent.categoryIdChanged(category.id),
                );
              }
            },
          ),
        );
      },
    );
  }

  Widget _buildCategoryShimmer() {
    return SliverToBoxAdapter(
      child: Container(
        height: 60,
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
        child: Shimmer.fromColors(
          baseColor: Colors.grey[300]!,
          highlightColor: Colors.grey[100]!,
          child: Row(
            children: List.generate(
              4,
              (index) => Container(
                margin: EdgeInsets.only(right: index < 3 ? 12 : 0),
                width: 80,
                height: 35,
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.circular(20),
                ),
              ),
            ),
          ),
        ),
      ),
    );
  }

  Widget _buildProductContent(ProductLoaderState state) {
    if (state.isFetching && state.products.isEmpty) {
      return currentViewType == ViewType.grid
          ? _buildProductGridShimmer()
          : _buildProductListShimmer();
    }

    if (state.products.isEmpty && !state.isFetching) {
      return SliverToBoxAdapter(
        child: EmptyWidget(
          title: 'Tidak ada produk ditemukan',
          message: 'Coba ubah filter atau tambah produk baru',
        ),
      );
    }

    return currentViewType == ViewType.grid
        ? _buildProductGrid(state.products)
        : _buildProductList(state.products);
  }

  Widget _buildProductGridShimmer() {
    return SliverPadding(
      padding: const EdgeInsets.all(16.0),
      sliver: SliverGrid(
        gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
          crossAxisCount: 2,
          childAspectRatio: 0.85,
          crossAxisSpacing: 16.0,
          mainAxisSpacing: 16.0,
        ),
        delegate: SliverChildBuilderDelegate((context, index) {
          return _buildProductTileShimmer();
        }, childCount: 6), // Show 6 shimmer items
      ),
    );
  }

  Widget _buildProductTileShimmer() {
    return Shimmer.fromColors(
      baseColor: Colors.grey[300]!,
      highlightColor: Colors.grey[100]!,
      child: Container(
        decoration: BoxDecoration(
          color: Colors.white,
          borderRadius: BorderRadius.circular(12),
        ),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            // Image shimmer
            Expanded(
              flex: 3,
              child: Container(
                width: double.infinity,
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.circular(12),
                ),
              ),
            ),
            // Content shimmer
            Expanded(
              flex: 2,
              child: Padding(
                padding: const EdgeInsets.all(12.0),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Container(
                      width: double.infinity,
                      height: 16,
                      color: Colors.white,
                    ),
                    const SizedBox(height: 8),
                    Container(width: 100, height: 12, color: Colors.white),
                    const Spacer(),
                    Container(width: 80, height: 14, color: Colors.white),
                  ],
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildProductListShimmer() {
    return SliverPadding(
      padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 8.0),
      sliver: SliverList(
        delegate: SliverChildBuilderDelegate((context, index) {
          return _buildProductListItemShimmer();
        }, childCount: 8), // Show 8 shimmer items
      ),
    );
  }

  Widget _buildProductListItemShimmer() {
    return Container(
      margin: const EdgeInsets.only(bottom: 12.0),
      decoration: BoxDecoration(
        color: Colors.white,
        borderRadius: BorderRadius.circular(12),
        boxShadow: [
          BoxShadow(
            color: Colors.grey.withOpacity(0.1),
            spreadRadius: 1,
            blurRadius: 6,
            offset: const Offset(0, 2),
          ),
        ],
      ),
      child: Shimmer.fromColors(
        baseColor: Colors.grey[300]!,
        highlightColor: Colors.grey[100]!,
        child: Padding(
          padding: const EdgeInsets.all(12.0),
          child: Row(
            children: [
              // Image shimmer
              Container(
                width: 80,
                height: 80,
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.circular(8),
                ),
              ),
              const SizedBox(width: 12),
              // Content shimmer
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Container(
                      width: double.infinity,
                      height: 16,
                      color: Colors.white,
                    ),
                    const SizedBox(height: 8),
                    Container(width: 120, height: 12, color: Colors.white),
                    const SizedBox(height: 12),
                    Row(
                      mainAxisAlignment: MainAxisAlignment.spaceBetween,
                      children: [
                        Container(width: 100, height: 16, color: Colors.white),
                        Container(
                          width: 60,
                          height: 24,
                          decoration: BoxDecoration(
                            color: Colors.white,
                            borderRadius: BorderRadius.circular(12),
                          ),
                        ),
                      ],
                    ),
                  ],
                ),
              ),
              const SizedBox(width: 8),
              // Action button shimmer
              Container(width: 24, height: 24, color: Colors.white),
            ],
          ),
        ),
      ),
    );
  }

  Widget _buildProductGrid(List<Product> products) {
    return SliverPadding(
      padding: const EdgeInsets.all(16.0),
      sliver: SliverGrid(
        gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
          crossAxisCount: 2,
          childAspectRatio: 0.75,
          crossAxisSpacing: 16.0,
          mainAxisSpacing: 16.0,
        ),
        delegate: SliverChildBuilderDelegate((context, index) {
          final product = products[index];
          return ProductTile(product: product, onTap: () {});
        }, childCount: products.length),
      ),
    );
  }

  Widget _buildProductList(List<Product> products) {
    return SliverPadding(
      padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 8.0),
      sliver: SliverList(
        delegate: SliverChildBuilderDelegate((context, index) {
          final product = products[index];
          return ProductCard(product: product);
        }, childCount: products.length),
      ),
    );
  }

  void _toggleViewType() {
    setState(() {
      currentViewType = currentViewType == ViewType.grid
          ? ViewType.list
          : ViewType.grid;
    });
  }
}