feat: added authentification and redirection

lib/ui/auth/widgets/login_page.dart

@@ -0,0 +1,92 @@
+import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
+import 'package:seshat/routing/routes.dart';
+import 'package:seshat/ui/auth/viewmodel/login_view_model.dart';
+
+class LoginPage extends StatefulWidget {
+  const LoginPage({super.key, required this.viewModel});
+
+  final LoginViewModel viewModel;
+
+  @override
+  State<LoginPage> createState() => _LoginPageState();
+}
+
+class _LoginPageState extends State<LoginPage> {
+  final TextEditingController _username = TextEditingController(
+    text: "ueauvergne",
+  );
+  final TextEditingController _password = TextEditingController(
+    text: "ueauvergne",
+  );
+
+  @override
+  void initState() {
+    super.initState();
+    widget.viewModel.login.addListener(_onResult);
+  }
+
+  @override
+  void didUpdateWidget(covariant LoginPage oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    oldWidget.viewModel.removeListener(_onResult);
+    widget.viewModel.login.addListener(_onResult);
+  }
+
+  @override
+  void dispose() {
+    widget.viewModel.login.removeListener(_onResult);
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      body: Column(
+        crossAxisAlignment: CrossAxisAlignment.center,
+        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+        children: [
+          TextField(controller: _username),
+          TextField(controller: _password),
+          ListenableBuilder(
+            listenable: widget.viewModel.login,
+            builder: (context, child) {
+              return FilledButton(
+                onPressed: () {
+                  widget.viewModel.login.execute((
+                    _username.value.text,
+                    _password.value.text,
+                  ));
+                },
+                child: Text("Connexion"),
+              );
+            },
+          ),
+        ],
+      ),
+    );
+  }
+
+  void _onResult() {
+    if (widget.viewModel.login.completed) {
+      widget.viewModel.login.clearResult();
+      context.go(Routes.add);
+    }
+
+    if (widget.viewModel.login.error) {
+      widget.viewModel.login.clearResult();
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text("Une erreur est survenue lors de la connexion."),
+          action: SnackBarAction(
+            label: "Réessayer",
+            onPressed: () => widget.viewModel.login.execute((
+              _username.value.text,
+              _password.value.text,
+            )),
+          ),
+        ),
+      );
+    }
+  }
+}