added frontend

hartmann-foto-documentation-frontend/lib/pages/login/login_widget.dart

@@ -0,0 +1,154 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+
+import 'package:go_router/go_router.dart';
+
+import 'package:fotodocumentation/controller/login_controller.dart';
+import 'package:fotodocumentation/dto/jwt_token_pair_dto.dart';
+import 'package:fotodocumentation/l10n/app_localizations.dart';
+import 'package:fotodocumentation/pages/ui_utils/component/general_submit_widget.dart';
+import 'package:fotodocumentation/pages/ui_utils/header_utils.dart';
+import 'package:fotodocumentation/pages/ui_utils/modern_app_bar.dart';
+import 'package:fotodocumentation/utils/di_container.dart';
+import 'package:fotodocumentation/utils/login_credentials.dart';
+
+class LoginWidget extends StatefulWidget {
+  const LoginWidget({super.key});
+
+  @override
+  State<LoginWidget> createState() => _LoginWidgetState();
+}
+
+class _LoginWidgetState extends State<LoginWidget> {
+  HeaderUtils get _headerUtils => DiContainer.get();
+  LoginController get _loginController => DiContainer.get();
+  LoginCredentials get _loginCredentials => DiContainer.get();
+
+  final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
+
+  final _usernameController = TextEditingController();
+  final _passwordController = TextEditingController();
+
+  String? _error;
+  final FocusNode _focusNode = FocusNode();
+
+  @override
+  void dispose() {
+    _focusNode.dispose();
+    _usernameController.dispose();
+    _passwordController.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: ModernAppBar(
+        title: _headerUtils.titleWidget("Login title"),
+        actions: [],
+      ),
+      body: _body(context),
+    );
+  }
+
+  Widget _body(BuildContext context) {
+    return Container(
+      decoration: BoxDecoration(
+        gradient: LinearGradient(
+          begin: Alignment.topCenter,
+          end: Alignment.bottomCenter,
+          colors: [
+            Colors.grey[50]!,
+            Colors.white,
+          ],
+        ),
+      ),
+      child: _content(context),
+    );
+  }
+
+  Widget _content(BuildContext context) {
+    return Padding(
+      padding: const EdgeInsets.all(20.0),
+      child: Form(
+        key: _formKey,
+        child: KeyboardListener(
+          focusNode: _focusNode,
+          onKeyEvent: (event) {
+            if (event is KeyDownEvent && event.logicalKey == LogicalKeyboardKey.enter) {
+              _actionSubmit(context);
+            }
+          },
+          child: ListView(
+            children: [
+              Card(
+                elevation: 4,
+                margin: EdgeInsets.zero,
+                clipBehavior: Clip.antiAlias,
+                child: Padding(
+                  padding: const EdgeInsets.all(30.0),
+                  child: Column(
+                    mainAxisAlignment: MainAxisAlignment.center,
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      TextFormField(
+                        key: Key("username"),
+                        controller: _usernameController,
+                        decoration: InputDecoration(
+                          border: UnderlineInputBorder(),
+                          labelText: AppLocalizations.of(context)!.loginUsernameTFLabel,
+                        ),
+                      ),
+                      const SizedBox(height: 10),
+                      TextFormField(
+                        key: Key("password"),
+                        controller: _passwordController,
+                        obscureText: true,
+                        decoration: InputDecoration(
+                          border: UnderlineInputBorder(),
+                          labelText: AppLocalizations.of(context)!.loginPasswordTFLabel,
+                        ),
+                      ),
+                      const SizedBox(height: 10),
+                      if (_error != null) ...[
+                        Text(
+                          _error!,
+                          style: const TextStyle(color: Colors.red),
+                        ),
+                        const SizedBox(height: 10),
+                      ],
+                      GeneralSubmitWidget(
+                        key: const Key("submit"),
+                        onSelect: () async => await _actionSubmit(context),
+                        title: AppLocalizations.of(context)!.loginLoginButtonLabel,
+                      ),
+                      const SizedBox(height: 30),
+                    ],
+                  ),
+                ),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  Future<void> _actionSubmit(BuildContext context) async {
+    String username = _usernameController.text;
+    String password = _passwordController.text;
+
+    AuthenticateReply authenticateReply = await _loginController.authenticate(username, password);
+
+    JwtTokenPairDto? jwtTokenPairDto = authenticateReply.jwtTokenPairDto;
+    if (jwtTokenPairDto == null) {
+      setState(() => _error = "Error message");
+      return;
+    }
+
+    _loginCredentials.setLoggedIn(true);
+    if (context.mounted) {
+      context.go("/");
+    }
+  }
+}