feat(frontend): simulate authenticated user sessions

eme-frontend/lib/screens/home_screen.dart

@@ -1,6 +1,7 @@
 import "package:flutter/material.dart";
 import "package:google_fonts/google_fonts.dart";
 import "../demo_identity.dart";
+import "../services/auth_service.dart";
 import "../theme/ensup_colors.dart";
 import "../widgets/ensup_top_bar.dart";
 import "../widgets/profile_card.dart";
@@ -13,6 +14,11 @@ import "restitution_select_screen.dart";
 class HomeScreen extends StatelessWidget {
   const HomeScreen({super.key});
 
+  void _quitter(BuildContext context) {
+    AuthService.clearSession();
+    Navigator.of(context).pop();
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -42,7 +48,7 @@ class HomeScreen extends StatelessWidget {
                       campusTag: DemoIdentity.campusTag,
                       userName: DemoIdentity.userName,
                       userInitials: DemoIdentity.userInitials,
-                      onBack: () => Navigator.of(context).pop(),
+                      onBack: () => _quitter(context),
                     ),
                     Expanded(
                       child: SingleChildScrollView(

eme-frontend/lib/screens/login_screen.dart

@@ -1,6 +1,7 @@
 import "package:flutter/material.dart";
 import "package:google_fonts/google_fonts.dart";
 import "../demo_identity.dart";
+import "../services/auth_service.dart";
 import "../theme/ensup_colors.dart";
 import "../widgets/ensup_top_bar.dart";
 import "../widgets/identification_option.dart";
@@ -13,6 +14,7 @@ class LoginScreen extends StatelessWidget {
   const LoginScreen({super.key});
 
   void _identifier(BuildContext context) {
+    AuthService.selectDemoStudent();
     Navigator.of(context).push(
       MaterialPageRoute(
         builder: (_) => const HomeScreen(),
@@ -21,6 +23,16 @@ class LoginScreen extends StatelessWidget {
     );
   }
 
+  void _identifierResponsable(BuildContext context) {
+    AuthService.selectDemoResponsable();
+    Navigator.of(context).push(
+      MaterialPageRoute(
+        builder: (_) => const ResponsableScreen(),
+        settings: const RouteSettings(name: "responsable"),
+      ),
+    );
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -162,15 +174,7 @@ class LoginScreen extends StatelessWidget {
                                     width: double.infinity,
                                     child: OutlinedButton.icon(
                                       onPressed: () =>
-                                          Navigator.of(context).push(
+                                          _identifierResponsable(context),
-                                            MaterialPageRoute(
-                                              builder: (_) =>
-                                                  const ResponsableScreen(),
-                                              settings: const RouteSettings(
-                                                name: "responsable",
-                                              ),
-                                            ),
-                                          ),
                                       icon: const Icon(
                                         Icons.person_outline,
                                         size: 16,

eme-frontend/lib/screens/responsable_screen.dart

@@ -2,6 +2,7 @@ import "package:flutter/material.dart";
 import "package:google_fonts/google_fonts.dart";
 
 import "../demo_identity.dart";
+import "../services/auth_service.dart";
 import "../services/responsable_service.dart";
 import "../theme/ensup_colors.dart";
 import "../utils/file_download.dart";
@@ -44,6 +45,11 @@ class _ResponsableScreenState extends State<ResponsableScreen> {
     setState(() => _future = _charger());
   }
 
+  void _quitter() {
+    AuthService.clearSession();
+    Navigator.of(context).pop();
+  }
+
   Future<void> _changerStatut(Map<String, dynamic> anomalie) async {
     final prochain = _prochainStatut(anomalie["statut"] as String?);
     if (prochain == null || _transitionEnCours) {
@@ -124,10 +130,7 @@ class _ResponsableScreenState extends State<ResponsableScreen> {
       body: SafeArea(
         child: Column(
           children: [
-            _ResponsableTopBar(
+            _ResponsableTopBar(onExit: _quitter, onRefresh: _rafraichir),
-              onExit: () => Navigator.of(context).pop(),
-              onRefresh: _rafraichir,
-            ),
             Expanded(
               child: FutureBuilder<_ResponsableData>(
                 future: _future,
@@ -249,7 +252,7 @@ class _ResponsableScreenState extends State<ResponsableScreen> {
                 anomaliesActives: anomaliesActives,
                 notificationsNonLues: notificationsNonLues,
                 onChanged: (index) => setState(() => _onglet = index),
-                onExit: () => Navigator.of(context).pop(),
+                onExit: _quitter,
               ),
             Expanded(
               child: Column(

eme-frontend/lib/services/api_client.dart

@@ -1,6 +1,7 @@
 import "dart:convert";
 import "dart:typed_data";
 import "package:http/http.dart" as http;
+import "auth_service.dart";
 
 /// Erreur levée par le client API (serveur injoignable ou réponse en échec).
 class ApiException implements Exception {
@@ -24,27 +25,19 @@ class ApiFile {
   final String contentType;
 }
 
-/// Point d'accès unique au backend : centralise l'URL de base, l'en-tête
+/// Point d'accès unique au backend : centralise l'URL, l'authentification et
-/// d'authentification (simulée) et la gestion des erreurs.
+/// la gestion des erreurs.
 class ApiClient {
   ApiClient._();
 
   static const String _baseUrl = "http://localhost:3000/api";
-  static const String _utilisateurEmail = "lucas.martin@ensitech.eu";
-  static const String responsableEmail = "karim.benali@ensup.eu";
 
-  static Future<dynamic> get(
+  static Future<dynamic> get(String chemin) async {
-    String chemin, {
-    String utilisateurEmail = _utilisateurEmail,
-  }) async {
     final uri = Uri.parse("$_baseUrl$chemin");
 
     late final http.Response reponse;
     try {
-      reponse = await http.get(
+      reponse = await http.get(uri, headers: AuthService.requestHeaders());
-        uri,
-        headers: {"x-user-email": utilisateurEmail},
-      );
     } catch (_) {
       throw const ApiException(
         "Impossible de joindre le serveur. Vérifiez que le backend est démarré.",
@@ -60,16 +53,12 @@ class ApiClient {
   static Future<ApiFile> getFile(
     String chemin, {
     required String fallbackFileName,
-    String utilisateurEmail = _utilisateurEmail,
   }) async {
     final uri = Uri.parse("$_baseUrl$chemin");
 
     late final http.Response reponse;
     try {
-      reponse = await http.get(
+      reponse = await http.get(uri, headers: AuthService.requestHeaders());
-        uri,
-        headers: {"x-user-email": utilisateurEmail},
-      );
     } catch (_) {
       throw const ApiException(
         "Impossible de joindre le serveur. Vérifiez que le backend est démarré.",
@@ -88,11 +77,7 @@ class ApiClient {
     );
   }
 
-  static Future<dynamic> post(
+  static Future<dynamic> post(String chemin, Map<String, dynamic> body) async {
-    String chemin,
-    Map<String, dynamic> body, {
-    String utilisateurEmail = _utilisateurEmail,
-  }) async {
     final uri = Uri.parse("$_baseUrl$chemin");
 
     late final http.Response reponse;
@@ -100,8 +85,8 @@ class ApiClient {
       reponse = await http.post(
         uri,
         headers: {
+          ...AuthService.requestHeaders(),
           "content-type": "application/json",
-          "x-user-email": utilisateurEmail,
         },
         body: jsonEncode(body),
       );
@@ -117,11 +102,7 @@ class ApiClient {
     throw ApiException(_messageErreur(reponse));
   }
 
-  static Future<dynamic> patch(
+  static Future<dynamic> patch(String chemin, Map<String, dynamic> body) async {
-    String chemin,
-    Map<String, dynamic> body, {
-    String utilisateurEmail = _utilisateurEmail,
-  }) async {
     final uri = Uri.parse("$_baseUrl$chemin");
 
     late final http.Response reponse;
@@ -129,8 +110,8 @@ class ApiClient {
       reponse = await http.patch(
         uri,
         headers: {
+          ...AuthService.requestHeaders(),
           "content-type": "application/json",
-          "x-user-email": utilisateurEmail,
         },
         body: jsonEncode(body),
       );

eme-frontend/lib/services/auth_service.dart

@@ -0,0 +1,63 @@
+enum AuthenticationMode { demo, azure }
+
+class AuthService {
+  AuthService._();
+
+  static const String _configuredMode = String.fromEnvironment(
+    "AUTH_MODE",
+    defaultValue: "demo",
+  );
+  static const String azureTenantId = String.fromEnvironment("AZURE_TENANT_ID");
+  static const String azureSpaClientId = String.fromEnvironment(
+    "AZURE_SPA_CLIENT_ID",
+  );
+  static const String azureApiScope = String.fromEnvironment("AZURE_API_SCOPE");
+
+  static const String demoStudentEmail = "lucas.martin@ensitech.eu";
+  static const String demoResponsableEmail = "karim.benali@ensup.eu";
+
+  static String? _demoEmail;
+
+  static AuthenticationMode get mode {
+    return switch (_configuredMode) {
+      "demo" => AuthenticationMode.demo,
+      "azure" => AuthenticationMode.azure,
+      _ => throw StateError("AUTH_MODE doit valoir demo ou azure."),
+    };
+  }
+
+  static void selectDemoStudent() {
+    _ensureDemoMode();
+    _demoEmail = demoStudentEmail;
+  }
+
+  static void selectDemoResponsable() {
+    _ensureDemoMode();
+    _demoEmail = demoResponsableEmail;
+  }
+
+  static void clearSession() {
+    _demoEmail = null;
+  }
+
+  static Map<String, String> requestHeaders() {
+    if (mode == AuthenticationMode.azure) {
+      throw StateError("La session Microsoft n'est pas encore initialisee.");
+    }
+
+    final email = _demoEmail;
+    if (email == null) {
+      throw StateError("Aucun utilisateur de demonstration selectionne.");
+    }
+
+    return {"x-user-email": email};
+  }
+
+  static void _ensureDemoMode() {
+    if (mode != AuthenticationMode.demo) {
+      throw StateError(
+        "Une identite de demonstration est interdite en mode Azure.",
+      );
+    }
+  }
+}

eme-frontend/lib/services/responsable_service.dart

@@ -4,13 +4,8 @@ import "api_client.dart";
 class ResponsableService {
   ResponsableService._();
 
-  static const String _email = ApiClient.responsableEmail;
-
   static Future<Map<String, dynamic>> dashboard() async {
-    final reponse = await ApiClient.get(
+    final reponse = await ApiClient.get("/responsable/dashboard");
-      "/responsable/dashboard",
-      utilisateurEmail: _email,
-    );
     return Map<String, dynamic>.from(reponse["data"] as Map);
   }
 
@@ -32,14 +27,12 @@ class ResponsableService {
   static Future<ApiFile> exporterHistorique() => ApiClient.getFile(
     "/responsable/historique/export.csv",
     fallbackFileName: "historique-responsable.csv",
-    utilisateurEmail: _email,
   );
 
   static Future<int> marquerNotificationsLues() async {
     final reponse = await ApiClient.patch(
       "/responsable/notifications/lu-toutes",
       {},
-      utilisateurEmail: _email,
     );
     final data = Map<String, dynamic>.from(reponse["data"] as Map);
     return data["count"] as int;
@@ -52,12 +45,12 @@ class ResponsableService {
     final reponse = await ApiClient.patch("/responsable/anomalies/$id/statut", {
       "statut": statut,
       "observation": "Traitement depuis l'interface responsable",
-    }, utilisateurEmail: _email);
+    });
     return Map<String, dynamic>.from(reponse["data"] as Map);
   }
 
   static Future<List<Map<String, dynamic>>> _liste(String chemin) async {
-    final reponse = await ApiClient.get(chemin, utilisateurEmail: _email);
+    final reponse = await ApiClient.get(chemin);
     final data = reponse["data"] as List;
     return data.map((item) => Map<String, dynamic>.from(item as Map)).toList();
   }