import 'package:flutter/material.dart';
import 'package:thesis_shop/bloc/product_bloc.dart';
import 'package:thesis_shop/bloc_provider.dart';
import 'package:thesis_shop/widgets/user_switch.dart';

import 'cart_button_overlay.dart';
import 'product_list.dart';

class ProductListScreen extends StatelessWidget {
  const ProductListScreen({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    final productBloc = AppState.of(context).blocProvider.productBloc;
    if (productBloc.productsState.isLoading()) {
      productBloc.loadProductSink.add(const LoadProductEvent());
    }
    return Scaffold(
      appBar: AppBar(
        title: const Text('Thesis Shop'),
        actions: [UserSwitch(isOn: true, onChanged: (_) {})],
      ),
      body: StreamBuilder<ProductsState>(
          stream: productBloc.productsStateStream,
          initialData: productBloc.productsState,
          builder: (context, snapshot) {
            final state = snapshot.requireData;
            if (state.isLoaded()) {
              return CartButtonOverlay(
                child:
                    ProductList(products: state.as<ProductsLoaded>().products),
              );
            } else if (state.hasError()) {
              return Center(
                child: Text(state.as<ProductsError>().errorMessage),
              );
            } else if (state.isLoading()) {
              return const Center(
                child: CircularProgressIndicator.adaptive(),
              );
            }
            throw UnimplementedError();
          }),
    );
  }
}