cake_wallet/lib/src/screens/auth/auth_page.dart

import 'package:mobx/mobx.dart';
import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
import 'package:cake_wallet/generated/i18n.dart';
import 'package:cake_wallet/view_model/auth_state.dart';
import 'package:cake_wallet/view_model/auth_view_model.dart';
import 'package:cake_wallet/src/screens/pin_code/pin_code.dart';
import 'package:cake_wallet/src/screens/pin_code/pin_code_widget.dart';
import 'package:cake_wallet/entities/biometric_auth.dart';
import 'package:cake_wallet/core/execution_state.dart';

typedef OnAuthenticationFinished = void Function(bool, AuthPageState);

class AuthPage extends StatefulWidget {
  AuthPage(this.authViewModel,
      {this.onAuthenticationFinished, this.closable = true});

  final AuthViewModel authViewModel;
  final OnAuthenticationFinished onAuthenticationFinished;
  final bool closable;

  @override
  AuthPageState createState() => AuthPageState();
}

class AuthPageState extends State<AuthPage> {
  final _key = GlobalKey<ScaffoldState>();
  final _pinCodeKey = GlobalKey<PinCodeState>();
  final _backArrowImageDarkTheme =
      Image.asset('assets/images/back_arrow_dark_theme.png');
  ReactionDisposer _reaction;

  @override
  void initState() {
    _reaction ??=
        reaction((_) => widget.authViewModel.state, (ExecutionState state) {
      if (state is ExecutedSuccessfullyState) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          if (widget.onAuthenticationFinished != null) {
            widget.onAuthenticationFinished(true, this);
          } else {
            _key.currentState.showSnackBar(
              SnackBar(
                content: Text(S.of(context).authenticated),
                backgroundColor: Colors.green,
              ),
            );
          }
        });
      }

      if (state is IsExecutingState) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          _key.currentState.showSnackBar(
            SnackBar(
              content: Text(S.of(context).authentication),
              backgroundColor: Colors.green,
            ),
          );
        });
      }

      if (state is FailureState) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          _pinCodeKey.currentState.clear();
          _key.currentState.hideCurrentSnackBar();
          _key.currentState.showSnackBar(
            SnackBar(
              content: Text(S.of(context).failed_authentication(state.error)),
              backgroundColor: Colors.red,
            ),
          );

          if (widget.onAuthenticationFinished != null) {
            widget.onAuthenticationFinished(false, this);
          }
        });
      }

      if (state is AuthenticationBanned) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          _pinCodeKey.currentState.clear();
          _key.currentState.hideCurrentSnackBar();
          _key.currentState.showSnackBar(
            SnackBar(
              content: Text(S.of(context).failed_authentication(state.error)),
              backgroundColor: Colors.red,
            ),
          );

          if (widget.onAuthenticationFinished != null) {
            widget.onAuthenticationFinished(false, this);
          }
        });
      }
    });

    if (widget.authViewModel.isBiometricalAuthenticationAllowed) {
      WidgetsBinding.instance.addPostFrameCallback((_) async {
        await Future<void>.delayed(Duration(milliseconds: 100));
        await widget.authViewModel.biometricAuth();
      });
    }

    super.initState();
  }

  @override
  void dispose() {
    _reaction.reaction.dispose();
    super.dispose();
  }

  void changeProcessText(String text) => _key.currentState.showSnackBar(
      SnackBar(content: Text(text), backgroundColor: Colors.green));

  void close() => Navigator.of(_key.currentContext).pop();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        key: _key,
        appBar: CupertinoNavigationBar(
            leading: widget.closable
                ? SizedBox(
                    height: 37,
                    width: 20,
                    child: ButtonTheme(
                      minWidth: double.minPositive,
                      child: FlatButton(
                          highlightColor: Colors.transparent,
                          splashColor: Colors.transparent,
                          padding: EdgeInsets.all(0),
                          onPressed: () => Navigator.of(context).pop(),
                          child: _backArrowImageDarkTheme),
                    ),
                  )
                : Container(),
            backgroundColor: Theme.of(context).backgroundColor,
            border: null),
        resizeToAvoidBottomPadding: false,
        body: PinCode((pin, _) => widget.authViewModel.auth(password: pin),
            (_) => null, widget.authViewModel.pinLength, false, _pinCodeKey));
  }
}