import 'package:flutter/material.dart';
import 'package:gymlink_module_web/components/app_bar.dart';
import 'package:gymlink_module_web/components/basket_item_card.dart';
import 'package:gymlink_module_web/components/heading.dart';
import 'package:gymlink_module_web/interfaces/items.dart';
import 'package:gymlink_module_web/pages/order_confirmation.dart';
import 'package:gymlink_module_web/providers/cart.dart';
import 'package:gymlink_module_web/tools/items.dart';
import 'package:gymlink_module_web/tools/prefs.dart';
import 'package:gymlink_module_web/tools/routes.dart';
import 'package:lazy_load_scrollview/lazy_load_scrollview.dart';
import 'package:provider/provider.dart';

List<Map<String, dynamic>> cart = [
  {
    "name": "Протеин",
    "image": "product.png",
    "price": "120",
    "details": "Test details",
    "id": "34fa3126-bfaf-5dec-8f4a-b246c097ef73"
  },
  {
    "name": "Протеин",
    "image": "product.png",
    "price": "150",
    "details": "Test details",
    "id": "34a26e82-7656-5e98-a44a-c2d01d0b1ad1123"
  },
  {
    "name": "Протеин",
    "image": "product.png",
    "price": "250",
    "details": "Test details",
    "id": "4fb204b7-3f9e-52a2-bed1-415c00a31a37123"
  },
  {
    "name": "Протеин",
    "image": "product.png",
    "price": "300",
    "details": "Test details",
    "id": "09b2f5bb-683e-5c39-ae89-b8e152fa8bcf123"
  },
  {
    "name": "Протеин",
    "image": "product.png",
    "price": "100",
    "details": "Test details",
    "id": "cd1b6817-db94-5394-be1d-af88af79749f123"
  }
];

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

  @override
  State<BasketPage> createState() => _BasketPageState();
}

class _BasketPageState extends State<BasketPage> {
  List<GymItem> cartItems = [];
  double totalPrice = 0;
  List<GymItem> gymCart = [];
  bool _isLoading = true;

  @override
  void initState() {
    super.initState();
    Future.microtask(() => getCart().then((value) async {
          final itemIds =
              value.map((element) => element['id'] as String).toList();
          final items = await getItemsByIds(context, itemIds);
          setState(() {
            gymCart = items;
            cartItems = value.map((element) {
              final item = gymCart.firstWhere((e) => e.id == element['id']);
              item.localCount = element['count'] as int;
              return item;
            }).toList();
            totalPrice = cartItems.fold(
                0, (sum, item) => sum + item.price * item.localCount);
            _isLoading = false;
          });
        }));
  }

  void _updateCart() {
    Provider.of<CartProvider>(context, listen: false).updateCartLength();
  }

  void removeItem(String id) async {
    final item = cartItems.firstWhere((element) => element.id == id);
    bool toDelete = false;
    setState(() {
      if (item.localCount > 1) {
        item.localCount--;
        cartItems[cartItems.indexOf(item)].localCount = item.localCount;
      } else {
        toDelete = true;
      }
      totalPrice =
          cartItems.fold(0, (sum, item) => sum + item.price * item.localCount);
    });
    if (toDelete) {
      await _deleteItemAlert(id, item.title);
    } else {
      await removeItemFromCart(id);
    }
  }

  void addItem(String id) async {
    setState(() {
      final item =
          cartItems.firstWhere((element) => element.id == id, orElse: () {
        final cartItem = gymCart.firstWhere((element) => element.id == id);
        cartItem.localCount = 0;
        return cartItem;
      });
      item.localCount++;
      cartItems[cartItems.indexOf(item)].localCount = item.localCount;
      totalPrice =
          cartItems.fold(0, (sum, item) => sum + item.price * item.localCount);
    });
    await addItemToCart(id);
  }

  Future<void> _deleteItemAlert(String id, String name) async {
    return showDialog<void>(
      context: context,
      barrierDismissible: true,
      builder: (BuildContext context) {
        return AlertDialog(
          title: const Text('Удаление из корзины'),
          content: SingleChildScrollView(
            child: ListBody(
              children: [
                Text('Вы действительно хотите убрать "$name" из корзины?'),
              ],
            ),
          ),
          actions: [
            TextButton(
              child: const Text('Отмена'),
              onPressed: () {
                Navigator.of(context).pop();
              },
            ),
            TextButton(
              child: const Text('Удалить'),
              onPressed: () {
                removeItemFromCart(id);
                setState(() {
                  cartItems.removeWhere((element) => element.id == id);
                });
                if (mounted) {
                  _updateCart();
                }
                Navigator.of(context).pop();
              },
            ),
          ],
        );
      },
    );
  }

  Future<void> _clearCartAlert() async {
    return showDialog<void>(
      context: context,
      barrierDismissible: true,
      builder: (BuildContext context) {
        return AlertDialog(
          title: const Text('Очистка корзины'),
          content: const SingleChildScrollView(
            child: ListBody(
              children: [
                Text('Вы действительно хотите очистить корзину?'),
              ],
            ),
          ),
          actions: [
            TextButton(
              child: const Text('Отмена'),
              onPressed: () {
                Navigator.of(context).pop();
              },
            ),
            TextButton(
              child: const Text('Очистить'),
              onPressed: () {
                clearCart();
                setState(() {
                  cartItems = [];
                });
                if (mounted) {
                  _updateCart();
                }
                Navigator.of(context).pop();
              },
            ),
          ],
        );
      },
    );
  }

  Widget _buildRowOrCol(
      {required BuildContext context, required List<Widget> children}) {
    if (MediaQuery.of(context).size.width > 600) {
      return Row(children: children);
    }
    return Column(children: children);
  }

  Widget _buildSpacer() {
    if (MediaQuery.of(context).size.width > 600) {
      return const Spacer();
    }
    return const SizedBox(height: 10);
  }

  void _onLoad() async {
    await Future.delayed(const Duration(microseconds: 1000));

    setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: const GymLinkAppBar(),
      body: Column(
        children: [
          const GymLinkHeader(title: "Корзина"),
          _isLoading
              ? const Expanded(
                  child: Center(child: CircularProgressIndicator()))
              : cartItems.isEmpty
                  ? Expanded(
                      child: Center(
                        child: Column(
                          mainAxisAlignment: MainAxisAlignment.center,
                          children: [
                            Text('Корзина пуста',
                                style: Theme.of(context).textTheme.bodyLarge),
                            const SizedBox(height: 10),
                            ElevatedButton(
                              onPressed: () => Navigator.pop(context, true),
                              style: ElevatedButton.styleFrom(
                                backgroundColor: Theme.of(context).primaryColor,
                                shape: const RoundedRectangleBorder(
                                  borderRadius:
                                      BorderRadius.all(Radius.circular(50)),
                                ),
                                foregroundColor: Colors.white,
                              ),
                              child: const Text('Вернуться назад'),
                            ),
                          ],
                        ),
                      ),
                    )
                  : Expanded(
                      child: _buildRowOrCol(
                        context: context,
                        children: [
                          Expanded(
                            child: LazyLoadScrollView(
                              onEndOfPage: _onLoad,
                              child: ListView.builder(
                                itemCount: cartItems.length,
                                itemBuilder: (context, index) {
                                  final item = cartItems[index];
                                  return BasketItemCard(
                                    name: item.title,
                                    price: item.price.toString(),
                                    id: item.id,
                                    image: Image(
                                      image: NetworkImage(item.images[0].url),
                                      width: 50,
                                    ),
                                    onTapPlus: () =>
                                        addItem(item.id.toString()),
                                    onTapMinus: () {
                                      removeItem(item.id.toString());
                                    },
                                    quantity: item.localCount.toString(),
                                  );
                                },
                              ),
                            ),
                          ),
                          _buildSpacer(),
                          Padding(
                            padding: const EdgeInsetsDirectional.symmetric(
                                horizontal: 10, vertical: 10),
                            child: Column(
                              children: [
                                Text(
                                  'Итого: $totalPrice руб.',
                                ),
                                ElevatedButton(
                                  onPressed: () => Navigator.of(context).push(
                                    CustomPageRoute(
                                      builder: (context) =>
                                          const OrderConfirmationPage(),
                                    ),
                                  ),
                                  style: ElevatedButton.styleFrom(
                                    backgroundColor:
                                        Theme.of(context).primaryColor,
                                    shape: const RoundedRectangleBorder(
                                      borderRadius:
                                          BorderRadius.all(Radius.circular(50)),
                                    ),
                                    foregroundColor: Colors.white,
                                  ),
                                  child: const Text('Оформить заказ'),
                                ),
                                const SizedBox(height: 10),
                                ElevatedButton(
                                  onPressed: _clearCartAlert,
                                  style: ElevatedButton.styleFrom(
                                    backgroundColor:
                                        Theme.of(context).primaryColor,
                                    shape: const RoundedRectangleBorder(
                                        borderRadius: BorderRadius.all(
                                            Radius.circular(50))),
                                    foregroundColor: Colors.white,
                                  ),
                                  child: const Text('Очистить корзину'),
                                ),
                              ],
                            ),
                          ),
                          const SizedBox(width: 50),
                        ],
                      ),
                    ),
        ],
      ),
    );
  }
}