Program won't log a user in despite submitting the proper credentials

I feel like I'm missing something whenever I review my program's code. Can't seem to figure out why it won't log a user in despite the user account existing and providing the correct password (all 3 accounts in my firebase has the same simple password).

the auth form

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:chat_app2/widgets/pickers/user_image_picker.dart';

class AuthForm extends StatefulWidget {
  AuthForm(this.submitFn, this.isLoading);

  final bool isLoading;
  final void Function(String email, String password, String username,
      File image, bool isLogin, BuildContext ctx) submitFn;

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

class _AuthFormState extends State<AuthForm> {
  final _formKey = GlobalKey<FormState>();
  var _isLogin = true;
  String _userEmail = '';
  String _userName = '';
  String _userPassword = '';
  File? _userImageFile;

  void _pickedImage(File image) {
    _userImageFile = image;
  }

  void _trySubmit() {
    final isValid = _formKey.currentState?.validate() ?? false;
    FocusScope.of(context).unfocus();

    if (_userImageFile == null && !_isLogin) {
      final snackBar = SnackBar(
        content: Text("please pick an image"),
        backgroundColor: Theme.of(context).errorColor,
      );
      ScaffoldMessenger.of(context).showSnackBar(snackBar);
      return;
    }

    if (isValid && _userImageFile != null) {
      _formKey.currentState?.save();
      widget.submitFn(
        _userEmail.trim(),
        _userName.trim(),
        _userPassword.trim(),
        _userImageFile!,
        _isLogin,
        context,
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Card(
        margin: EdgeInsets.all(20),
        child: SingleChildScrollView(
          child: Padding(
            padding: EdgeInsets.all(16),
            child: Form(
              key: _formKey,
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: <Widget>[
                  if (!_isLogin) UserImagePicker(_pickedImage),
                  TextFormField(
                    key: ValueKey('email'),
                    validator: (value) {
                      if (value!.isEmpty || !value.contains('@')) {
                        return 'Please enter a valid email address';
                      }
                      return null;
                    },
                    keyboardType: TextInputType.emailAddress,
                    decoration: InputDecoration(
                      labelText: 'Email address',
                    ),
                    onSaved: (value) {
                      _userEmail = value ?? "";
                    },
                  ),
                  if (!_isLogin)
                    TextFormField(
                      key: ValueKey('userName'),
                      validator: (value) {
                        if (value!.isEmpty || value.length < 4) {
                          return 'Please enter at least four characters';
                        }
                        return null;
                      },
                      decoration: InputDecoration(labelText: 'Username'),
                      onSaved: (value) {
                        _userName = value ?? "";
                      },
                    ),
                  TextFormField(
                    key: ValueKey('password'),
                    validator: (value) {
                      if (value!.isEmpty || value.length < 7) {
                        return 'Password must be at least seven characters long';
                      }
                      return null;
                    },
                    decoration: InputDecoration(labelText: 'Password'),
                    obscureText: true,
                    onSaved: (value) {
                      _userPassword = value ?? "";
                    },
                  ),
                  SizedBox(
                    height: 12,
                  ),
                  if (widget.isLoading) CircularProgressIndicator(),
                  if (!widget.isLoading)
                    ElevatedButton(
                      child: Text(_isLogin ? 'Login' : 'Sign up'),
                      onPressed: _trySubmit,
                      style: ElevatedButton.styleFrom(
                          shape: RoundedRectangleBorder(
                        borderRadius: BorderRadius.circular(20),
                      )),
                    ),
                  if (!widget.isLoading)
                    TextButton(
                      child: Text(_isLogin
                          ? 'Create new account'
                          : 'I already have an account'),
                      onPressed: () {
                        setState(() {
                          _isLogin = !_isLogin;
                        });
                      },
                      style: TextButton.styleFrom(
                        foregroundColor: Theme.of(context).primaryColor,
                      ),
                    ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }
}

the auth screen

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:cloud_firestore/cloud_firestore.dart';

import 'package:chat_app2/widgets/auth/auth_form.dart';
import 'package:flutter/services.dart';
import 'package:firebase_storage/firebase_storage.dart';

class AuthScreen extends StatefulWidget {
  @override
  _AuthScreenState createState() => _AuthScreenState();
}

class _AuthScreenState extends State<AuthScreen> {
  final _auth = FirebaseAuth.instance;
  var _isLoading = false;
  void _submitAuthForm(String email, String username, String password,
      File image, bool isLogin, BuildContext ctx) async {
    UserCredential authResult;
    try {
      setState(() {
        _isLoading = true;
      });
      if (isLogin) {
        authResult = await _auth.signInWithEmailAndPassword(
          email: email,
          password: password,
        );
      } else {
        authResult = await _auth.createUserWithEmailAndPassword(
          email: email,
          password: password,
        );

        final ref = FirebaseStorage.instance
            .ref()
            .child('user_image')
            .child(authResult.user!.uid + '.jpg');

        var uploadTask = ref.putFile(image);
        var storageTaskSnapshot = await uploadTask;
        String url = await storageTaskSnapshot.ref.getDownloadURL();

        await FirebaseFirestore.instance
            .collection('users')
            .doc(authResult.user!.uid)
            .set({
          'username': username,
          'email': email,
          'image_url': url,
        });
      }
    } on PlatformException catch (err) {
      var message = 'An error occured, please check your credentials';
      if (err.message != null) {
        message = err.message!;
      }
      final snackBar = SnackBar(
        content: Text(message),
        backgroundColor: Theme.of(ctx).errorColor,
      );
      ScaffoldMessenger.of(ctx).showSnackBar(snackBar);
      setState(() {
        _isLoading = false;
      });
    } catch (err) {
      final snackBar = SnackBar(
        content: Text(err.toString()),
        backgroundColor: Theme.of(ctx).errorColor,
      );
      ScaffoldMessenger.of(ctx).showSnackBar(snackBar);
      setState(() {
        _isLoading = false;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Theme.of(context).primaryColor,
      body: AuthForm(
        _submitAuthForm,
        _isLoading,
      ),
    );
  }
}

Code used to work fine up until I added image upload from device camera functionality. Fixed the errors that came with it but now it won't sign in user accounts. Code signs in newly created users just fine so I'm not sure what's happening in the code开发者_Go百科.

Edit: Included main program due to me not entirely sure if there could be a logic problem within it as well.

Main form

import 'package:chat_app2/screens/chat_screen.dart';
import 'package:flutter/material.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:firebase_auth/firebase_auth.dart';
import './screens/auth_screen.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Chat',
      theme: ThemeData(
        primarySwatch: Colors.pink,
        backgroundColor: Colors.pink,
        accentColor: Colors.deepPurple,
        accentColorBrightness: Brightness.dark,
        buttonTheme: ButtonTheme.of(context).copyWith(
          buttonColor: Colors.pink,
          textTheme: ButtonTextTheme.primary,
          shape:
              RoundedRectangleBorder(borderRadius: BorderRadius.circular(20)),
        ),
      ),
      home: StreamBuilder(
        stream: FirebaseAuth.instance.authStateChanges(),
        builder: (ctx, userSnapshot) {
          if (userSnapshot.hasData) {
            return ChatScreen();
          }
          return AuthScreen();
        },
      ),
    );
  }
}