TaxSaver

Overview

This is the code for this video on Youtube by Siraj Raval titled "Watch ChatGPT Build a Finance Startup". Use it as a starting template to build your own finance startup!

Dependencies

• Flutter
• VS Code
• Git
• Optional GitHub CoPilot

Setup & Installation

---

Step 1: Install Flutter

Flutter is an open source framework by Google for building natively compiled, multi-platform applications from a single codebase. That could be iOS, Android, Web, MacOS, Linux, & more. In this example, we're just going to focus on mobile platforms (iOS & Android) Flutter uses a language called Dart, which compiles down to native Swift and Java, for iOS and Android respectively. The best way to learn Flutter is to complete steps 1-3 of the official Flutter beginner tutorial. You'll need dependencies for each platform you'd like to push to, so in our case that means Xcode & Android Studio.

Install Link

Step 2: Download & run this code

Download the code with the following command in a command-line interface on your operating system of choice:

git clone https://github.com/llSourcell/TaxSaver

then enter the examples repository:

cd TaxSaver/examples

and install all dependencies from the pubspec.yaml file with the following command:

flutter pub get

and add your test user/pass to the users.dart file!

Lastly, run the app with this command:

flutter run

Now you can customize the UI to your particular needs (or not!)

Step 3: Add Plaid to get transaction history

Plaid provides developers with tools to connect users financial institutions to apps they love. Go to Plaid.com and signup to get an API key. Then integrate it with this plugin titled plaid-flutter. You'll need to generate a link token. I just curl'd it from command line and pasted it into the app to get Plaid's Link View to show up.

Find detailed instructions here

Plaid example code to start Plaid Login

 final configuration = LinkTokenConfiguration(
                    token: 'link-sandbox-YOURCODE');
                await PlaidLink.open(configuration: configuration);

Step 4: Integrate GPT-3 to interpret financial data for tax savings

Once plaid is connected, it's time to use GPT-3 to read transaction history. The Completion API is one way of analyzing the data, using the entire transaction history as a prompt, then asking it categorize transactions and tell us which ones are likely tax deductible. Signup for OpenAI API, then install the flutter plugin titled openai_gpt3_api

Flutter example using openai_gpt3_api

 Future<String> gptCall() async {
    var api = GPT3('<YOUR KEY>');
    var result = await api.completion("What are top spending categories that usually get tax refunds?");
        'What are top spending categories that usually get tax refunds?');
    print(result);
    var choices = result.choices;
    print(choices[0].text);
    print(result.toJson());
    return choices[0].text;
  }

Step 5: Integrate Firebase

Firebase is a user database by Google that is pretty much GCP but for mobile. It's got everything you need so that you don't have to build and maintain your own web server for webhooks and API requests for iOS or Android. It works especially well with Flutter. Signup for it and get an API key. Create a project and follow the instructions to integrate this app with firebase. The goal here is to instead of logging into a local textfile, login to the Firebase server.

Example Firebase Flutter code

FirebaseAuth.instance
  .authStateChanges()
  .listen((User? user) {
    if (user == null) {
      print('User is currently signed out!');
    } else {
      print('User is signed in!');
    }
  });

Future Directions

• Generate 1099, and other tax reports
• Better UI

Credits

This was built on a fork on flutter-login by Nearhuscarl. See below.

Flutter Login

FlutterLogin is a ready-made login/signup widget with many animation effects to demonstrate the capabilities of Flutter

Installation

Follow the install instructions here

Reference

Property	Type	Description
onSignup	AuthCallback	Called when the user hit the submit button when in sign up mode. It receives a SignupData object, with name, password and, if additionalSignUpFields is not null, the additional fields filled in by the user in a Map<String,String>
onConfirmSignup	ConfirmSignupCallback	Called when the user hits the submit button when confirming signup. If not specified, signup will not be confirmed by user.
confirmSignupKeyboardType	TextInputType	The keyboard type of the confirm signup field
onResendCode	AuthCallback	Called when the user hits the resend code button when confirming signup. Only required when onConfirmSignup is provided.
onLogin	AuthCallback	Called when the user hit the submit button when in login mode
onRecoverPassword	RecoverCallback	Called when the user hit the submit button when in recover password mode
onConfirmRecover	ConfirmRecoverCallback	Called when the user submits confirmation code and sets password in recover password mode. If not specified, a confirmation code will not be used to recover password.
title	String	The large text above the login [Card], usually the app or company name. Leave the string empty or null if you want no title.
logo	ImageProvider or String	The image provider or asset path string for the logo image to be displayed
messages	LoginMessages	Describes all of the labels, text hints, button texts and other auth descriptions
theme	LoginTheme	FlutterLogin's theme. If not specified, it will use the default theme as shown in the demo gifs and use the colorsheme in the closest Theme widget
userType	LoginUserType	FlutterLogin's user type. If not specified, it will use the default user type as email
userValidator	FormFieldValidator<String>	User field validating logic, add your custom validation here. The default is email validation logic. Expects to return an error message [String] to be display if validation fails or [null] if validation succeeds
passwordValidator	FormFieldValidator<String>	Same as userValidator but for password
onSubmitAnimationCompleted	Function	Called after the submit animation's completed. Put your route transition logic here
logoTag	String	Hero tag for logo image. If not specified, it will simply fade out when changing route
titleTag	String	Hero tag for title text. Need to specify LoginTheme.beforeHeroFontSize and LoginTheme.afterHeroFontSize if you want different font size before and after hero animation
showDebugButtons	bool	Display the debug buttons to quickly forward/reverse login animations. In release mode, this will be overridden to false regardless of the value passed in
hideForgotPasswordButton	bool	Hides the Forgot Password button if set to true
hideProvidersTitle	bool	Hides the title above login providers if set to true. In case the providers List is empty this is uneffective, as the title is hidden anyways. The default is false
disableCustomPageTransformer	bool	Disables the custom transition which causes RenderBox was not laid out error. See #97 for more info.
additionalSignUpFields	Map<String, UserFormField>	Used to specify the additional form fields; the form is shown right after signin up. You can provide at most 6 additional fields.
onSwitchToAdditionalFields	AdditionalFieldsCallback	Called when the user switches to additional fields.
navigateBackAfterRecovery	bool	Navigate back to the login page after successful recovery.
savedEmail	String	Prefilled value for user field (ie. saved from previous session via other means, ie. via SharedPreferences)
savedPassword	String	Prefilled value for password field (ie. saved from previous session via other means, ie. via SharedPreferences). Will set also confirmation password in Auth class
termsOfService	TermOfService	List of terms of service to be listed during registration. On onSignup callback LoginData contains a list of TermOfServiceResult
children	[Widget]	List of widgets that can be added to the stack of the login screen. Can be used to show custom banners or logos.
scrollable	bool	When set to true, the login card becomes scrollable instead of resizing when needed.
headerWidget	Widget	A widget that can be placed on top of the loginCard.

NOTE: It is recommended that the child widget of the Hero widget should be the same in both places. For title's hero animation use the LoginThemeHelper.loginTextStyle in the next screen to get the style of the exact text widget in the login screen. LoginThemeHelper can be accessed by adding this line

import 'package:flutter_login/theme.dart';

LoginMessages

Property	Type	Description
userHint	String	Hint text of the user field [TextField] (Note: user field can be name, email or phone. For more info check: LoginUserType)
passwordHint	String	Hint text of the password [TextField]
confirmPasswordHint	String	Hint text of the confirm password [TextField]
forgotPasswordButton	String	Forgot password button's label
loginButton	String	Login button's label
signupButton	String	Signup button's label
recoverPasswordButton	String	Recover password button's label
recoverPasswordIntro	String	Intro in password recovery form
recoverPasswordDescription	String	Description in password recovery form, shown when the onConfirmRecover callback is not provided
recoverCodePasswordDescription	String	Description in password recovery form, shown when the onConfirmRecover callback is provided
goBackButton	String	Go back button's label. Go back button is used to go back to to login/signup form from the recover password form
confirmPasswordError	String	The error message to show when the confirm password not match with the original password
recoverPasswordSuccess	String	The success message to show after submitting recover password
confirmSignupIntro	String	The intro text for the confirm signup card
confirmationCodeHint	String	Hint text of the confirmation code [TextField]
confirmationCodeValidationError	String	The error message to show if confirmation code is empty
resendCodeButton	String	Resend code button's label
resendCodeSuccess	String	The success message to show after resending a confirmation code
confirmSignupButton	String	Confirm signup button's label
confirmSignupSuccess	String	The success message to show after confirming signup
confirmRecoverIntro	String	The intro text for the confirm recover password card
recoveryCodeHint	String	Hint text of the recovery code [TextField]
recoveryCodeValidationError	String	The error message to show if recovery code is empty
setPasswordButton	String	Set password button's label for password recovery
confirmRecoverSuccess	String	The success message to show after confirming recovered password
flushbarTitleError	String	The Flushbar title on errors
flushbarTitleSuccess	String	The Flushbar title on successes
providersTitle	String	A string shown above the login Providers, defaults to or login with

LoginTheme

Property	Type	Description
primaryColor	Color	The background color of major parts of the widget like the login screen and buttons
accentColor	Color	The secondary color, used for title text color, loading icon, etc. Should be contrast with the [primaryColor]
errorColor	Color	The color to use for [TextField] input validation errors
cardTheme	CardTheme	The colors and styles used to render auth [Card]
inputTheme	InputDecorationTheme	Defines the appearance of all [TextField]s
buttonTheme	LoginButtonTheme	A theme for customizing the shape, elevation, and color of the submit button
titleStyle	TextStyle	Text style for the big title
bodyStyle	TextStyle	Text style for small text like the recover password description
textFieldStyle	TextStyle	Text style for [TextField] input text
buttonStyle	TextStyle	Text style for button text
beforeHeroFontSize	double	Defines the font size of the title in the login screen (before the hero transition)
afterHeroFontSize	double	Defines the font size of the title in the screen after the login screen (after the hero transition)
pageColorLight	Color	The optional light background color of login screen; if provided, used for light gradient instead of primaryColor
pageColorDark	Color	The optional dark background color of login screen; if provided, used for dark gradient instead of primaryColor
footerBottomPadding	double	The footer bottom Padding; defaults to 0 if not provided.
switchAuthTextColor	Color	The optional color for the switch authentication text, if nothing is specified [primaryColor] is used.
logoWidth	double	Width of the logo where 1 is the full width of the login card. ; defaults to 0.75 if not provided.
primaryColorAsInputLabel	bool	Set to true if you want to use the primary color for input labels. Defaults to false.

LoginUserType

Enum	Description
EMAIL	The User Field will be set to be email
NAME	The User Field will be set to be username
PHONE	The User Field will be set to be phone

[LoginUserType] will change how the user field [TextField] behaves. Autofills and Keyboard Type will be adjusted automatically for the type of user that you pass.

UserFormField

Property	Type	Description
keyName	String	The identifier of the fields, it will be the key in the returned map. Please ensure this is unique, otherwise an Error will be thrown
displayName	String	The name of the field displayed on the form. Defaults to keyName if not given
defaultValue	String	The default value of the field, if given the field will be pre-filled in with this
fieldValidator	FormFieldValidator<String>	A function to validate the field. It should return null on success, or a string with the explanation of the error
icon	Icon?	The icon shown on the left of the field. Defaults to the user icon when not provided
userType	LoginUserType	The LoginUserType of the form. The right keyboard and suggestions will be shown accordingly. Defaults to LoginUserType.user

LoginProvider

Property	Type	Description
button	Widget	Used for Buttons for [LoginProvider] - see example uses [SignInButton] package
icon	IconData	Icon that is used for a button for [LoginProvider]
label	String	The label shown under the provider
callback	ProviderAuthCallback	A Function called when the provider button is pressed. It must return null on success, or a String describing the error on failure.
providerNeedsSignUpCallback	ProviderNeedsSignUpCallback?	Optional. Requires that the additionalSignUpFields argument is passed to FlutterLogin. When given, this callback must return a Future<bool>. If it evaluates to true the card containing the additional signup fields is shown, right after the evaluation of callback. If not given the default behaviour is not to show the signup card.

NOTE: Both [button] and [icon] can be added to [LoginProvider], but [button] will take preference over [icon]

TermOfService

Property	Type	Description
id	String	Used only on Signup callback to identify a single Term Of service if it's optional.
mandatory	bool	If set true and term is not check when form is validate on submit, the validation error message will be shown
text	String	Name of Term to show.
linkUrl	String	Web url link to additional term of services info.
validationErrorMessage	String	Validation error message to show.
initialValue	bool	Specify if checkbox is initialized checked

TermOfServiceResult

Property	Type	Description
term	TermOfService	Contains a termOfServiceObject.
accepted	bool	Indicates whether or not the term of service was selected during registration

Examples

You can view the complete example in the example project which resulted in the gif above

Basic example

import 'package:flutter/material.dart';
import 'package:flutter_login/flutter_login.dart';
import 'dashboard_screen.dart';

const users = const {
  'dribbble@gmail.com': '12345',
  'hunter@gmail.com': 'hunter',
};

class LoginScreen extends StatelessWidget {
  Duration get loginTime => Duration(milliseconds: 2250);

  Future<String?> _authUser(LoginData data) {
    debugPrint('Name: ${data.name}, Password: ${data.password}');
    return Future.delayed(loginTime).then((_) {
      if (!users.containsKey(data.name)) {
        return 'User not exists';
      }
      if (users[data.name] != data.password) {
        return 'Password does not match';
      }
      return null;
    });
  }

  Future<String?> _signupUser(SignupData data) {
    debugPrint('Signup Name: ${data.name}, Password: ${data.password}');
    return Future.delayed(loginTime).then((_) {
      return null;
    });
  }

  Future<String> _recoverPassword(String name) {
    debugPrint('Name: $name');
    return Future.delayed(loginTime).then((_) {
      if (!users.containsKey(name)) {
        return 'User not exists';
      }
      return null;
    });
  }

  @override
  Widget build(BuildContext context) {
    return FlutterLogin(
      title: 'ECORP',
      logo: AssetImage('assets/images/ecorp-lightblue.png'),
      onLogin: _authUser,
      onSignup: _signupUser,
      onSubmitAnimationCompleted: () {
        Navigator.of(context).pushReplacement(MaterialPageRoute(
          builder: (context) => DashboardScreen(),
        ));
      },
      onRecoverPassword: _recoverPassword,
    );
  }
}

Basic example with sign in providers

import 'package:flutter/material.dart';
import 'package:flutter_login/flutter_login.dart';
import 'dashboard_screen.dart';

const users = const {
  'dribbble@gmail.com': '12345',
  'hunter@gmail.com': 'hunter',
};

class LoginScreen extends StatelessWidget {
  Duration get loginTime => Duration(milliseconds: 2250);

  Future<String?> _authUser(LoginData data) {
    debugPrint('Name: ${data.name}, Password: ${data.password}');
    return Future.delayed(loginTime).then((_) {
      if (!users.containsKey(data.name)) {
        return 'User not exists';
      }
      if (users[data.name] != data.password) {
        return 'Password does not match';
      }
      return null;
    });
  }

  Future<String?> _signupUser(SignupData data) {
    debugPrint('Signup Name: ${data.name}, Password: ${data.password}');
    return Future.delayed(loginTime).then((_) {
      return null;
    });
  }

  Future<String> _recoverPassword(String name) {
    debugPrint('Name: $name');
    return Future.delayed(loginTime).then((_) {
      if (!users.containsKey(name)) {
        return 'User not exists';
      }
      return null;
    });
  }

  @override
  Widget build(BuildContext context) {
    return FlutterLogin(
      title: 'ECORP',
      logo: AssetImage('assets/images/ecorp-lightblue.png'),
      onLogin: _authUser,
      onSignup: _signupUser,
      
        loginProviders: <LoginProvider>[
          LoginProvider(
            icon: FontAwesomeIcons.google,
            label: 'Google',
            callback: () async {
              debugPrint('start google sign in');
              await Future.delayed(loginTime);
              debugPrint('stop google sign in');              
              return null;
            },
          ),
          LoginProvider(
            icon: FontAwesomeIcons.facebookF,
            label: 'Facebook',
            callback: () async {            
              debugPrint('start facebook sign in');
              await Future.delayed(loginTime);
              debugPrint('stop facebook sign in');              
              return null;
            },
          ),
          LoginProvider(
            icon: FontAwesomeIcons.linkedinIn,
            callback: () async {         
              debugPrint('start linkdin sign in');
              await Future.delayed(loginTime);         
              debugPrint('stop linkdin sign in');              
              return null;
            },
          ),
          LoginProvider(
            icon: FontAwesomeIcons.githubAlt,
            callback: () async {
              debugPrint('start github sign in');
              await Future.delayed(loginTime);
              debugPrint('stop github sign in');              
              return null;
            },
          ),
        ],
      onSubmitAnimationCompleted: () {
        Navigator.of(context).pushReplacement(MaterialPageRoute(
          builder: (context) => DashboardScreen(),
        ));
      },
      onRecoverPassword: _recoverPassword,
    );
  }
}

Theming via ThemeData

Login theme can be customized indectly by using ThemeData like this

// main.dart
import 'package:flutter/material.dart';
import 'login_screen.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Login Demo',
      theme: ThemeData(
        primarySwatch: Colors.deepPurple,
        accentColor: Colors.orange,
        cursorColor: Colors.orange,
        textTheme: TextTheme(
          headline3: TextStyle(
            fontFamily: 'OpenSans',
            fontSize: 45.0,
            color: Colors.orange,
          ),
          button: TextStyle(
            fontFamily: 'OpenSans',
          ),
          subtitle1: TextStyle(fontFamily: 'NotoSans'),
          bodyText2: TextStyle(fontFamily: 'NotoSans'),
        ),
      ),
      home: LoginScreen(),
    );
  }
}

// login_screen.dart
import 'package:flutter/material.dart';
import 'package:flutter_login/flutter_login.dart';
import 'dashboard_screen.dart';

class LoginScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return FlutterLogin(
      title: 'ECORP',
      logo: AssetImage('assets/images/ecorp.png'),
      onLogin: (_) => Future(null),
      onSignup: (_) => Future(null),
      onSubmitAnimationCompleted: () {
        Navigator.of(context).pushReplacement(MaterialPageRoute(
          builder: (context) => DashboardScreen(),
        ));
      },
      onRecoverPassword: (_) => Future(null),
    );
  }
}

Custom labels

import 'package:flutter/material.dart';
import 'package:flutter_login/flutter_login.dart';
import 'dashboard_screen.dart';

class LoginScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return FlutterLogin(
      title: 'ECORP',
      logo: AssetImage('assets/images/ecorp.png'),
      onLogin: (_) => Future(null),
      onSignup: (_) => Future(null),
      onSubmitAnimationCompleted: () {
        Navigator.of(context).pushReplacement(MaterialPageRoute(
          builder: (context) => DashboardScreen(),
        ));
      },
      onRecoverPassword: (_) => Future(null),
      messages: LoginMessages(
        userHint: 'User',
        passwordHint: 'Pass',
        confirmPasswordHint: 'Confirm',
        loginButton: 'LOG IN',
        signupButton: 'REGISTER',
        forgotPasswordButton: 'Forgot huh?',
        recoverPasswordButton: 'HELP ME',
        goBackButton: 'GO BACK',
        confirmPasswordError: 'Not match!',
        recoverPasswordDescription:
            'Lorem Ipsum is simply dummy text of the printing and typesetting industry',
        recoverPasswordSuccess: 'Password rescued successfully',
      ),
    );
  }
}

Login/Signup	Password Recovery

Theme customization

import 'package:flutter/material.dart';
import 'package:flutter_login/flutter_login.dart';
import 'dashboard_screen.dart';

class LoginScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final inputBorder = BorderRadius.vertical(
      bottom: Radius.circular(10.0),
      top: Radius.circular(20.0),
    );

    return FlutterLogin(
      title: 'ECORP',
      logo: AssetImage('assets/images/ecorp-lightgreen.png'),
      onLogin: (_) => Future(null),
      onSignup: (_) => Future(null),
      onSubmitAnimationCompleted: () {
        Navigator.of(context).pushReplacement(MaterialPageRoute(
          builder: (context) => DashboardScreen(),
        ));
      },
      onRecoverPassword: (_) => Future(null),
      theme: LoginTheme(
        primaryColor: Colors.teal,
        accentColor: Colors.yellow,
        errorColor: Colors.deepOrange,
        titleStyle: TextStyle(
          color: Colors.greenAccent,
          fontFamily: 'Quicksand',
          letterSpacing: 4,
        ),
        bodyStyle: TextStyle(
          fontStyle: FontStyle.italic,
          decoration: TextDecoration.underline,
        ),
        textFieldStyle: TextStyle(
          color: Colors.orange,
          shadows: [Shadow(color: Colors.yellow, blurRadius: 2)],
        ),
        buttonStyle: TextStyle(
          fontWeight: FontWeight.w800,
          color: Colors.yellow,
        ),
        cardTheme: CardTheme(
          color: Colors.yellow.shade100,
          elevation: 5,
          margin: EdgeInsets.only(top: 15),
          shape: ContinuousRectangleBorder(
              borderRadius: BorderRadius.circular(100.0)),
        ),
        inputTheme: InputDecorationTheme(
          filled: true,
          fillColor: Colors.purple.withOpacity(.1),
          contentPadding: EdgeInsets.zero,
          errorStyle: TextStyle(
            backgroundColor: Colors.orange,
            color: Colors.white,
          ),
          labelStyle: TextStyle(fontSize: 12),
          enabledBorder: UnderlineInputBorder(
            borderSide: BorderSide(color: Colors.blue.shade700, width: 4),
            borderRadius: inputBorder,
          ),
          focusedBorder: UnderlineInputBorder(
            borderSide: BorderSide(color: Colors.blue.shade400, width: 5),
            borderRadius: inputBorder,
          ),
          errorBorder: UnderlineInputBorder(
            borderSide: BorderSide(color: Colors.red.shade700, width: 7),
            borderRadius: inputBorder,
          ),
          focusedErrorBorder: UnderlineInputBorder(
            borderSide: BorderSide(color: Colors.red.shade400, width: 8),
            borderRadius: inputBorder,
          ),
          disabledBorder: UnderlineInputBorder(
            borderSide: BorderSide(color: Colors.grey, width: 5),
            borderRadius: inputBorder,
          ),
        ),
        buttonTheme: LoginButtonTheme(
          splashColor: Colors.purple,
          backgroundColor: Colors.pinkAccent,
          highlightColor: Colors.lightGreen,
          elevation: 9.0,
          highlightElevation: 6.0,
          shape: BeveledRectangleBorder(
            borderRadius: BorderRadius.circular(10),
          ),
          // shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(5)),
          // shape: CircleBorder(side: BorderSide(color: Colors.green)),
          // shape: ContinuousRectangleBorder(borderRadius: BorderRadius.circular(55.0)),
        ),
      ),
    );
  }
}

Inspiration

• VNPAY App Interactions
• Flat UI Login animated

License

• MIT License