import 'package:dart_core_sdk/handlingunit.pb.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:grpc/grpc.dart';
import 'package:sampleapp/services/grpc_service.dart';
import 'package:sampleapp/widgets/components/reflex_app_bar.dart';
import 'package:provider/provider.dart';
import 'package:sampleapp/widgets/components/reflex_circular_progress.dart';

import '../globals.dart';
import '../locator.dart';
import '../services/auth/auth.dart';
import '../services/auth/auth_view_model.dart';
import 'scan_flow/delivery_confirmed.dart' as sf;
import 'scan_flow/select_context_screen.dart' as sf;
import 'scan_flow/scan_barcode_screen.dart' as sf;
import 'scan_flow/scan_result_screen.dart' as sf;

const routePrefixHome = '/home/';
const routeHome = '/home/$routeSelectContext';
const routeSelectContext = 'select_context';
const routeScanBarCode = 'scan_barcode';
const routeScanResult = 'scan_result';
const routeDeliveryConfirmed = 'delivery_confirmed';

class HomeScreen extends StatefulWidget {
  final VoidCallback onLogout;

  const HomeScreen({super.key, required this.onLogout});

  @override
  State<StatefulWidget> createState() {
    return HomeScreenState();
  }
}

class HomeScreenState extends State<HomeScreen> {
  final _navigatorKey = GlobalKey<NavigatorState>();
  String? _projectID;
  String? _handlingUnitID;
  Handlingunit? _handlingUnit;
  bool? _isDeliveryValid;

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

  Future<void> _logout(AuthViewModel avm) async {
    showDialog(
        barrierDismissible: false,
        context: context,
        builder: (context) => const Center(child: ReflexCircularProgress()));
    await avm.logout().then((result) => {
          Navigator.of(context, rootNavigator: true).pop(),
          if (result) widget.onLogout()
        });
  }

  void _onContextSelected(String projectID) {
    _projectID = projectID;
    _navigatorKey.currentState!.pushNamed(routeScanBarCode);
  }

  void _onBarCodeScanned(String handlingUnitRefId, Handlingunit? handlingUnitResult) {
    _handlingUnit = handlingUnitResult;
    _handlingUnitID = handlingUnitRefId;
    _navigatorKey.currentState!.pushNamed(routeScanResult);
  }

  void _onDeliveryConfirmed(bool isDeliveryValid) {
    _isDeliveryValid = isDeliveryValid;
    _navigatorKey.currentState!.pushNamed(routeDeliveryConfirmed);
  }

  void _onNextDelivery() {
    _navigatorKey.currentState!.pushNamedAndRemoveUntil(
        routeScanBarCode, ModalRoute.withName(routeSelectContext));
  }

  Route _onGenerateRoute(RouteSettings settings) {
    late Widget page;
    switch (settings.name) {
      case routeSelectContext:
        page = sf.SelectContext(onContextSelected: _onContextSelected);
        break;
      case routeScanBarCode:
        page = sf.ScanBarcode(
            onBarcodeScanned: _onBarCodeScanned, projectID: _projectID!);
        break;
      case routeScanResult:
        page = sf.ScanResult(
            refID: _handlingUnitID!,
            handlingUnit: _handlingUnit,
            projectID: _projectID!,
            onDeliveryConfirmed: _onDeliveryConfirmed);
        break;
      case routeDeliveryConfirmed:
        page = sf.DeliveryConfirmed(
          projectID: _projectID!,
          handlingUnit: _handlingUnit!,
          isDeliveryValid: _isDeliveryValid!,
          onNextDelivery: _onNextDelivery,
        );
        break;
      default:
        page = Text(settings.name!);
    }

    return CupertinoPageRoute<dynamic>(
      builder: (context) {
        return page;
      },
      settings: settings,
    );
  }

  @override
  Widget build(BuildContext context) {
    final authViewModel = context.watch<AuthViewModel>();
    return WillPopScope(
        onWillPop: () async {
          if (_navigatorKey.currentState!.canPop()) {
            _navigatorKey.currentState!.pop();
            return false;
          }
          return true;
        },
        child: Scaffold(
            appBar: ReflexAppBar(
                actions: [
                  IconButton(
                      icon: const Icon(
                          Icons.logout,
                          color: Colors.white,
                      ),
                      onPressed: () => _logout(authViewModel)
                  )
                ],
                onBackCallback: () => {
                      if (_navigatorKey.currentState!.canPop())
                        {_navigatorKey.currentState!.pop()}
                    }),
            body: Navigator(
                key: _navigatorKey,
                initialRoute: routeSelectContext,
                onGenerateRoute: _onGenerateRoute)));
  }
}