feat: two step login

example/pubspec.lock

@@ -68,7 +68,11 @@ packages:
       path: ".."
       relative: true
     source: path
+<<<<<<< HEAD
     version: "6.0.0"
+=======
+    version: "5.2.0"
+>>>>>>> 60112c8 (feat: two step login)
   flutter_test:
     dependency: "direct dev"
     description: flutter
@@ -79,30 +83,6 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
-  leak_tracker:
-    dependency: transitive
-    description:
-      name: leak_tracker
-      sha256: "78eb209deea09858f5269f5a5b02be4049535f568c07b275096836f01ea323fa"
-      url: "https://pub.dev"
-    source: hosted
-    version: "10.0.0"
-  leak_tracker_flutter_testing:
-    dependency: transitive
-    description:
-      name: leak_tracker_flutter_testing
-      sha256: b46c5e37c19120a8a01918cfaf293547f47269f7cb4b0058f21531c2465d6ef0
-      url: "https://pub.dev"
-    source: hosted
-    version: "2.0.1"
-  leak_tracker_testing:
-    dependency: transitive
-    description:
-      name: leak_tracker_testing
-      sha256: a597f72a664dbd293f3bfc51f9ba69816f84dcd403cdac7066cb3f6003f3ab47
-      url: "https://pub.dev"
-    source: hosted
-    version: "2.0.1"
   lints:
     dependency: transitive
     description:
@@ -115,34 +95,34 @@ packages:
     dependency: transitive
     description:
       name: matcher
-      sha256: d2323aa2060500f906aa31a895b4030b6da3ebdcc5619d14ce1aada65cd161cb
+      sha256: "1803e76e6653768d64ed8ff2e1e67bea3ad4b923eb5c56a295c3e634bad5960e"
       url: "https://pub.dev"
     source: hosted
-    version: "0.12.16+1"
+    version: "0.12.16"
   material_color_utilities:
     dependency: transitive
     description:
       name: material_color_utilities
-      sha256: "0e0a020085b65b6083975e499759762399b4475f766c21668c4ecca34ea74e5a"
+      sha256: "9528f2f296073ff54cb9fee677df673ace1218163c3bc7628093e7eed5203d41"
       url: "https://pub.dev"
     source: hosted
-    version: "0.8.0"
+    version: "0.5.0"
   meta:
     dependency: transitive
     description:
       name: meta
-      sha256: d584fa6707a52763a52446f02cc621b077888fb63b93bbcb1143a7be5a0c0c04
+      sha256: a6e590c838b18133bb482a2745ad77c5bb7715fb0451209e1a7567d416678b8e
       url: "https://pub.dev"
     source: hosted
-    version: "1.11.0"
+    version: "1.10.0"
   path:
     dependency: transitive
     description:
       name: path
-      sha256: "087ce49c3f0dc39180befefc60fdb4acd8f8620e5682fe2476afd0b3688bb4af"
+      sha256: "8829d8a55c13fc0e37127c29fedf290c102f4e40ae94ada574091fe0ff96c917"
       url: "https://pub.dev"
     source: hosted
-    version: "1.9.0"
+    version: "1.8.3"
   pinput:
     dependency: transitive
     description:
@@ -228,14 +208,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.4"
-  vm_service:
+  web:
     dependency: transitive
     description:
-      name: vm_service
+      name: web
-      sha256: b3d56ff4341b8f182b96aceb2fa20e3dcb336b9f867bc0eafc0de10f1048e957
+      sha256: afe077240a270dcfd2aafe77602b4113645af95d0ad31128cc02bce5ac5d5152
       url: "https://pub.dev"
     source: hosted
-    version: "13.0.0"
+    version: "0.3.0"
 sdks:
-  dart: ">=3.2.0-0 <4.0.0"
+  dart: ">=3.2.0-194.0.dev <4.0.0"
   flutter: ">=3.7.0"

lib/flutter_login.dart

@@ -9,3 +9,4 @@ export 'src/service/validation.dart';
 export 'src/widgets/email_password_login.dart';
 export 'src/widgets/forgot_password_form.dart';
 export 'src/widgets/mfa_widget.dart';
+export 'src/widgets/two_step_login.dart';

lib/src/widgets/two_step_login.dart

@@ -0,0 +1,175 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_login/flutter_login.dart';
+
+class TwoStepLoginForm extends StatefulWidget {
+  /// Constructs an [TwoStepLoginForm] widget.
+  ///
+  /// [onCheckEmail]: Callback function for when a user has filled in its email
+  /// [options]: The options for configuring the login form.
+  const TwoStepLoginForm({
+    required this.onCheckEmail,
+    super.key,
+    this.options = const LoginOptions(),
+  });
+
+  final LoginOptions options;
+  final FutureOr<void> Function(String email) onCheckEmail;
+  @override
+  State<TwoStepLoginForm> createState() => _TwoStepLoginFormState();
+}
+
+class _TwoStepLoginFormState extends State<TwoStepLoginForm> {
+  final _formKey = GlobalKey<FormState>();
+  final ValueNotifier<bool> _formValid = ValueNotifier(false);
+  bool _obscurePassword = true;
+
+  String _currentEmail = '';
+
+  void _updateCurrentEmail(String email) {
+    _currentEmail = email;
+    _validate();
+  }
+
+  void _validate() {
+    late var isValid =
+        widget.options.validations.validateEmail(_currentEmail) == null;
+    if (isValid != _formValid.value) {
+      _formValid.value = isValid;
+    }
+  }
+
+  Future<void> _handleLogin() async {
+    if (mounted) {
+      var form = _formKey.currentState!;
+      if (form.validate()) {
+        await widget.onCheckEmail(
+          _currentEmail,
+        );
+      }
+    }
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    _currentEmail = widget.options.initialEmail;
+    _validate();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    var theme = Theme.of(context);
+    var options = widget.options;
+    return CustomScrollView(
+      physics: const ScrollPhysics(),
+      slivers: [
+        SliverFillRemaining(
+          hasScrollBody: false,
+          fillOverscroll: true,
+          child: Column(
+            children: [
+              Expanded(
+                flex: options.spacers.titleSpacer,
+                child: Column(
+                  children: [
+                    if (options.spacers.spacerBeforeTitle != null) ...[
+                      Spacer(flex: options.spacers.spacerBeforeTitle!),
+                    ],
+                    if (options.title != null) ...[
+                      Align(
+                        alignment: Alignment.topCenter,
+                        child: _wrapWithDefaultStyle(
+                          options.title,
+                          theme.textTheme.headlineSmall,
+                        ),
+                      ),
+                    ],
+                    if (options.spacers.spacerAfterTitle != null) ...[
+                      Spacer(flex: options.spacers.spacerAfterTitle!),
+                    ],
+                    if (options.subtitle != null) ...[
+                      Align(
+                        alignment: Alignment.topCenter,
+                        child: _wrapWithDefaultStyle(
+                          options.subtitle,
+                          theme.textTheme.titleSmall,
+                        ),
+                      ),
+                    ],
+                    if (options.spacers.spacerAfterSubtitle != null) ...[
+                      Spacer(flex: options.spacers.spacerAfterSubtitle!),
+                    ],
+                    if (options.image != null) ...[
+                      Padding(
+                        padding: const EdgeInsets.all(16),
+                        child: options.image,
+                      ),
+                    ],
+                    if (options.spacers.spacerAfterImage != null) ...[
+                      Spacer(flex: options.spacers.spacerAfterImage!),
+                    ],
+                  ],
+                ),
+              ),
+              Expanded(
+                flex: options.spacers.formFlexValue,
+                child: ConstrainedBox(
+                  constraints: BoxConstraints(
+                    maxWidth: options.maxFormWidth ?? 300,
+                  ),
+                  child: Form(
+                    key: _formKey,
+                    child: Column(
+                      mainAxisSize: MainAxisSize.min,
+                      children: [
+                        options.emailInputContainerBuilder(
+                          TextFormField(
+                            onChanged: _updateCurrentEmail,
+                            validator: widget.options.validations.validateEmail,
+                            initialValue: options.initialEmail,
+                            keyboardType: TextInputType.emailAddress,
+                            textInputAction: TextInputAction.next,
+                            style: options.emailTextStyle,
+                            decoration: options.emailDecoration,
+                          ),
+                        ),
+                        if (options.spacers.spacerAfterForm != null) ...[
+                          Spacer(flex: options.spacers.spacerAfterForm!),
+                        ],
+                        AnimatedBuilder(
+                          animation: _formValid,
+                          builder: (context, _) => options.loginButtonBuilder(
+                            context,
+                            _handleLogin,
+                            !_formValid.value,
+                            () {
+                              _formKey.currentState?.validate();
+                            },
+                            options,
+                          ),
+                        ),
+                        if (options.spacers.spacerAfterButton != null) ...[
+                          Spacer(flex: options.spacers.spacerAfterButton!),
+                        ],
+                      ],
+                    ),
+                  ),
+                ),
+              ),
+            ],
+          ),
+        ),
+      ],
+    );
+  }
+
+  Widget? _wrapWithDefaultStyle(Widget? widget, TextStyle? style) {
+    if (style == null || widget == null) {
+      return widget;
+    } else {
+      return DefaultTextStyle(style: style, child: widget);
+    }
+  }
+}