form: move files, restructure

lib/features/login/presentation/pages/login_page_email.dart

@@ -1,5 +1,4 @@
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/email_is_valid.dart';
 import 'package:coffeecard/core/widgets/fast_slide_transition.dart';
 import 'package:coffeecard/features/login/presentation/pages/login_page_base.dart';
 import 'package:coffeecard/features/login/presentation/pages/login_page_passcode.dart';
@@ -8,6 +7,12 @@ import 'package:coffeecard/features/login/presentation/widgets/login_email_text_
 import 'package:coffeecard/features/register/presentation/pages/register_flow.dart';
 import 'package:flutter/material.dart';
 
+// FIXME: Duplicate code.
+//  Rewrite the LoginPageEmail widget to use the Form widget,
+//  such that we can use input validators.
+final _isValidEmail =
+    RegExp(r'^[^@ \t\r\n]+@[^@ \t\r\n]+\.[^@ \t\r\n]{2,}').hasMatch;
+
 class LoginPageEmail extends StatefulWidget {
   const LoginPageEmail({this.transitionDuration = Duration.zero});
 
@@ -50,7 +55,7 @@ class _LoginPageEmailState extends State<LoginPageEmail>
   void _validateEmail(BuildContext context, String email) {
     if (email.isEmpty) {
       error = Strings.loginEnterEmailError;
-    } else if (!emailIsValid(email)) {
+    } else if (!_isValidEmail(email)) {
       error = Strings.loginInvalidEmailError;
     } else {
       final _ =

lib/features/login/presentation/widgets/forgot_passcode_form.dart

@@ -1,10 +1,9 @@
 import 'package:coffeecard/core/ignore_value.dart';
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
 import 'package:coffeecard/core/widgets/components/dialog.dart';
 import 'package:coffeecard/core/widgets/components/loading_overlay.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
 import 'package:coffeecard/features/login/data/datasources/account_remote_data_source.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:coffeecard/service_locator.dart';
 import 'package:flutter/material.dart';
 import 'package:fpdart/fpdart.dart';
@@ -34,7 +33,7 @@ class ForgotPasscodeForm extends StatelessWidget {
             return emailExistsResult.fold(
               (error) => const Left(Strings.emailValidationError),
               (emailExists) => emailExists
-                  ? const Right(null)
+                  ? const Right(unit)
                   : const Left(Strings.forgotPasscodeNoAccountExists),
             );
           },

lib/features/register/presentation/widgets/forms/register_email_form.dart

@@ -1,7 +1,6 @@
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
 import 'package:coffeecard/features/login/data/datasources/account_remote_data_source.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:coffeecard/service_locator.dart';
 import 'package:flutter/material.dart';
 import 'package:fpdart/fpdart.dart';
@@ -30,7 +29,7 @@ class RegisterEmailForm extends StatelessWidget {
               (l) => const Left(Strings.emailValidationError),
               (r) => r
                   ? Left(Strings.registerEmailInUse(text))
-                  : const Right(null),
+                  : const Right(unit),
             );
           },
         ),

lib/features/register/presentation/widgets/forms/register_name_form.dart

@@ -1,11 +1,10 @@
 import 'package:coffeecard/core/ignore_value.dart';
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
 import 'package:coffeecard/core/widgets/components/dialog.dart';
 import 'package:coffeecard/core/widgets/components/helpers/unordered_list_builder.dart';
 import 'package:coffeecard/core/widgets/components/loading_overlay.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
 import 'package:coffeecard/features/register/presentation/cubit/register_cubit.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:gap/gap.dart';

lib/features/register/presentation/widgets/forms/register_passcode_form.dart

@@ -1,6 +1,5 @@
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:flutter/material.dart';
 
 class RegisterPasscodeForm extends StatelessWidget {

lib/features/register/presentation/widgets/forms/register_passcode_repeat_form.dart

@@ -1,6 +1,5 @@
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:flutter/material.dart';
 
 class RegisterPasscodeRepeatForm extends StatelessWidget {

lib/features/settings/presentation/widgets/forms/change_email_form.dart

@@ -1,7 +1,6 @@
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
 import 'package:coffeecard/features/login/data/datasources/account_remote_data_source.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:coffeecard/service_locator.dart';
 import 'package:flutter/material.dart';
 import 'package:fpdart/fpdart.dart';
@@ -37,7 +36,7 @@ class ChangeEmailForm extends StatelessWidget {
               (l) => const Left(Strings.emailValidationError),
               (r) => r
                   ? Left(Strings.registerEmailInUse(text))
-                  : const Right(null),
+                  : const Right(unit),
             );
           },
         ),

lib/features/settings/presentation/widgets/forms/change_name_form.dart

@@ -1,6 +1,5 @@
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:coffeecard/features/user/presentation/cubit/user_cubit.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';

lib/features/settings/presentation/widgets/forms/change_passcode_form.dart

@@ -1,8 +1,7 @@
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
 import 'package:coffeecard/core/widgets/fast_slide_transition.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
 import 'package:coffeecard/features/settings/presentation/widgets/forms/change_passcode_repeat_form.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:flutter/material.dart';
 
 class ChangePasscodeForm extends StatelessWidget {

lib/features/settings/presentation/widgets/forms/change_passcode_repeat_form.dart

@@ -1,7 +1,6 @@
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
 import 'package:coffeecard/core/widgets/fast_slide_transition.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:coffeecard/features/user/presentation/cubit/user_cubit.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';

lib/features/shared/form.dart

@@ -0,0 +1 @@
+export 'package:coffeecard/src/shared/form/form.dart';

lib/features/voucher/presentation/widgets/voucher_form.dart

@@ -1,6 +1,5 @@
 import 'package:coffeecard/core/strings.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
-import 'package:coffeecard/features/form/presentation/widgets/form.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:coffeecard/features/voucher/presentation/cubit/voucher_cubit.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';

lib/features/form/presentation/bloc/form_bloc.dart → lib/src/shared/form/bloc/form_bloc.dart

@@ -1,6 +1,5 @@
 import 'package:bloc/bloc.dart';
-import 'package:coffeecard/core/debouncing.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:equatable/equatable.dart';
 import 'package:fpdart/fpdart.dart';
 
@@ -25,7 +24,7 @@ class FormBloc extends Bloc<FormEvent, FormState> {
               state.copyWith(
                 loading: false,
                 canSubmit: false,
-                error: either,
+                validationStatus: either,
                 shouldDisplayError: validator.forceErrorMessage ? true : null,
               ),
             );
@@ -37,7 +36,7 @@ class FormBloc extends Bloc<FormEvent, FormState> {
             loading: false,
             text: text,
             canSubmit: true,
-            error: const Right(null),
+            validationStatus: const Right(unit),
           ),
         );
       },

lib/features/form/presentation/bloc/form_state.dart → lib/src/shared/form/bloc/form_state.dart

@@ -6,37 +6,37 @@ class FormState extends Equatable {
     this.text = '',
     this.canSubmit = false,
     this.shouldDisplayError = false,
-    this.error = const Right(null),
+    this.validationStatus = const Right(unit),
   });
 
   final bool loading;
   final String text;
   final bool canSubmit;
   final bool shouldDisplayError;
-  final ErrorEither error;
+  final Either<String, Unit> validationStatus;
 
   @override
   List<Object?> get props => [
         loading,
         text,
         canSubmit,
         shouldDisplayError,
-        error,
+        validationStatus,
       ];
 
   FormState copyWith({
     bool? loading,
     String? text,
     bool? canSubmit,
     bool? shouldDisplayError,
-    ErrorEither? error,
+    Either<String, Unit>? validationStatus,
   }) {
     return FormState(
       loading: loading ?? this.loading,
       text: text ?? this.text,
       canSubmit: canSubmit ?? this.canSubmit,
       shouldDisplayError: shouldDisplayError ?? this.shouldDisplayError,
-      error: error ?? this.error,
+      validationStatus: validationStatus ?? this.validationStatus,
     );
   }
 }

lib/src/shared/form/form.dart

@@ -0,0 +1,4 @@
+export 'bloc/debouncing.dart';
+export 'bloc/form_bloc.dart';
+export 'input_validator/input_validator.dart';
+export 'widgets/form.dart';

lib/core/validator/input_validator.dart → lib/src/shared/form/input_validator/input_validator.dart

@@ -1,21 +1,17 @@
 import 'dart:async';
 
-import 'package:coffeecard/core/validator/email_is_valid.dart';
 import 'package:fpdart/fpdart.dart';
 
 part 'input_validator_helpers.dart';
 
-/// Either an input error message (String) or a valid input (void).
-typedef ErrorEither = Either<String, void>;
-
-/// A content validator for `AppForm`s.
+/// A content validator for [FormBase] widgets.
 ///
 /// Example:
 /// ```dart
 /// class ExampleForm extends StatelessWidget {
 ///   @override
 ///   Widget build(BuildContext context) {
-///     return AppForm(
+///     return FormBase(
 ///       inputValidators: [
 ///         InputValidator.bool(
 ///           validate: (input) => input.length == 4,
@@ -54,14 +50,14 @@ class InputValidator {
   }) : this(
           validate: (String input) async {
             final validInput = await validate(input);
-            return validInput ? const Right(null) : Left(errorMessage);
+            return validInput ? const Right(unit) : Left(errorMessage);
           },
           forceErrorMessage: forceErrorMessage,
         );
 
   /// The input validator. Either returns an
   /// error message (left) or success (right).
-  final FutureOr<ErrorEither> Function(String input) validate;
+  final FutureOr<Either<String, Unit>> Function(String input) validate;
 
   /// If failing this input validator should show an error message,
   /// even if the user has not pressed submit yet.

lib/core/validator/input_validator_helpers.dart → lib/src/shared/form/input_validator/input_validator_helpers.dart

@@ -11,7 +11,7 @@ class InputValidators {
 
   static InputValidator validEmail({required String errorMessage}) {
     return InputValidator.bool(
-      validate: emailIsValid,
+      validate: RegExp(r'^[^@ \t\r\n]+@[^@ \t\r\n]+\.[^@ \t\r\n]{2,}').hasMatch,
       errorMessage: errorMessage,
     );
   }

lib/features/form/presentation/widgets/form.dart → lib/src/shared/form/widgets/form.dart

@@ -1,9 +1,8 @@
 import 'package:coffeecard/core/strings.dart';
 import 'package:coffeecard/core/styles/app_colors.dart';
-import 'package:coffeecard/core/validator/input_validator.dart';
 import 'package:coffeecard/core/widgets/components/rounded_button.dart';
 import 'package:coffeecard/core/widgets/components/section_title.dart';
-import 'package:coffeecard/features/form/presentation/bloc/form_bloc.dart';
+import 'package:coffeecard/features/shared/form.dart';
 import 'package:flutter/material.dart' hide FormState;
 import 'package:flutter/services.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
@@ -79,7 +78,6 @@ class FormBase extends StatelessWidget {
         listenWhen: (_, current) => autoSubmitValidInput && current.canSubmit,
         listener: (_, state) => onSubmit(state.text),
         builder: (context, state) {
-          final bloc = context.read<FormBloc>();
           return Column(
             mainAxisAlignment: MainAxisAlignment.spaceBetween,
             crossAxisAlignment: CrossAxisAlignment.stretch,
@@ -93,12 +91,16 @@ class FormBase extends StatelessWidget {
                     inputValidators: inputValidators,
                     onChanged: (input) {
                       if (!state.loading) {
-                        bloc.add(FormValidateRequested());
+                        context.read<FormBloc>().add(FormValidateRequested());
                       }
-                      bloc.add(FormValidateStarted(input: input));
+                      context
+                          .read<FormBloc>()
+                          .add(FormValidateStarted(input: input));
                     },
                     onEditingComplete: () {
-                      bloc.add(FormToggleErrorDisplay(displayError: true));
+                      context
+                          .read<FormBloc>()
+                          .add(FormToggleErrorDisplay(displayError: true));
                       if (state.canSubmit) {
                         onSubmit(state.text);
                       }

lib/features/form/presentation/widgets/form_text_field.dart → lib/src/shared/form/widgets/form_text_field.dart

@@ -94,7 +94,7 @@ class _FormTextFieldState extends State<_FormTextField> {
   Widget build(BuildContext context) {
     return BlocBuilder<FormBloc, FormState>(
       builder: (context, state) {
-        final maybeError = state.error.fold((l) => l, (r) => null);
+        final maybeError = state.validationStatus.fold((l) => l, (r) => null);
 
         return Container(
           margin: const EdgeInsets.only(bottom: 12),