import 'package:barcode_scan2/barcode_scan2.dart';
import 'package:calorimeter/food_scan/food_fact_lookup.dart';
import 'package:calorimeter/utils/enter_food_controller.dart';
import 'package:calorimeter/utils/scan_food_floating_button.dart';
import 'package:calorimeter/utils/app_drawer.dart';
import 'package:calorimeter/food_entry/food_entry_bloc.dart';
import 'package:calorimeter/perdate/entry_list.dart';
import 'package:calorimeter/storage/storage.dart';
import 'package:calorimeter/utils/calendar_floating_button.dart';
import 'package:calorimeter/utils/rectangular_notch_shape.dart';
import 'package:calorimeter/utils/sum_widget.dart';
import 'package:calorimeter/utils/theme_switcher_button.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:intl/intl.dart';
import 'package:provider/provider.dart';

class PerDateWidget extends StatefulWidget {
  final DateTime date;
  const PerDateWidget({super.key, required this.date});

  @override
  State<PerDateWidget> createState() => _PerDateWidgetState();
}

class _PerDateWidgetState extends State<PerDateWidget> {
  late FoodStorage storage;
  late Future<List<FoodEntry>> entriesFuture;
  List<FoodEntry> entries = [];

  @override
  void initState() {
    storage = FoodStorage.getInstance();
    entriesFuture = storage.getEntriesForDate(widget.date);
    entriesFuture.then((val) {
      entries = val;
    });
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return FutureBuilder(
      future: entriesFuture,
      builder: (context, snapshot) {
        return snapshot.connectionState != ConnectionState.done
            ? const Center(child: CircularProgressIndicator())
            : MultiProvider(
                providers: [
                  ChangeNotifierProvider(
                      create: (context) => EnterFoodController()),
                  BlocProvider(
                    create: (context) => FoodEntryBloc(
                      initialState: FoodEntryState(foodEntries: entries),
                      storage: storage,
                      forDate: widget.date,
                    ),
                  )
                ],
                child: BlocBuilder<FoodEntryBloc, FoodEntryState>(
                  builder: (context, state) {
                    return Scaffold(
                        appBar: AppBar(
                          title:
                              Text(DateFormat.yMMMMd('de').format(widget.date)),
                          actions: const [ThemeSwitcherButton()],
                        ),
                        body: FoodEntryList(entries: state.foodEntries),
                        bottomNavigationBar: BottomAppBar(
                            shape: const RectangularNotchShape(),
                            color: Theme.of(context).colorScheme.secondary,
                            child: SumWidget(foodEntries: state.foodEntries)),
                        drawer: const AppDrawer(),
                        floatingActionButton: OverflowBar(
                          children: [
                            ScanFoodFloatingButton(onPressed: () {
                              _onScanButtonPressed(context);
                            }),
                            const SizedBox(width: 8),
                            CalendarFloatingButton(
                              startFromDate: widget.date,
                              onDateSelected: (dateSelected) {
                                _onDateSelected(dateSelected);
                              },
                            ),
                          ],
                        ),
                        floatingActionButtonLocation:
                            FloatingActionButtonLocation.endDocked);
                  },
                ),
              );
      },
    );
  }

  void showNewSnackbarWith(BuildContext context, String text) {
    var snackbar =
        ErrorSnackbar(colorScheme: Theme.of(context).colorScheme, text: text);

    ScaffoldMessenger.of(context)
      ..removeCurrentSnackBar()
      ..showSnackBar(snackbar);
  }

  void _onDateSelected(DateTime date) {
    Navigator.of(context).push(
      MaterialPageRoute(
        builder: (context) {
          return PerDateWidget(date: date);
        },
      ),
    ).then((val) {
      setState(
        () {
          entriesFuture = storage.getEntriesForDate(widget.date);
          entriesFuture.then(
            (val) {
              entries = val;
            },
          );
        },
      );
    });
  }

  void _onScanButtonPressed(BuildContext context) async {
    var client = FoodFactLookupClient();

    var scanResult = await BarcodeScanner.scan();

    if (scanResult.type == ResultType.Cancelled) {
      return;
    }

    if (!context.mounted) return;

    if (scanResult.type == ResultType.Error) {
      showNewSnackbarWith(context, "Fehler beim Scannen des Barcodes.");
    }
    var response = await client.retrieveFoodInfo(scanResult.rawContent);

    if (!context.mounted) return;

    if (response.status == FoodFactResponseStatus.barcodeNotFound) {
      showNewSnackbarWith(context, "Barcode konnte nicht gefunden werden.");
      return;
    }

    if (response.status == FoodFactResponseStatus.foodFactServerNotReachable) {
      showNewSnackbarWith(
          context, "OpenFoodFacts-Server konnte nicht erreicht werden.");
      return;
    }

    context.read<EnterFoodController>().set(
          response.food!.name,
          response.food!.kcalPer100g.toString(),
        );
  }
}

class ErrorSnackbar extends SnackBar {
  final String text;
  final ColorScheme colorScheme;
  ErrorSnackbar({
    required this.text,
    required this.colorScheme,
    super.key,
  }) : super(
            content: Text(text, style: TextStyle(color: colorScheme.onError)),
            backgroundColor: colorScheme.error);
}