feat: made the ongoing screen... for now

lib/data/repositories/bal_repository.dart

@@ -55,6 +55,12 @@ class BalRepository {
         false;
   }
 
+  Future<Result<Bal>> stopBal(int id) async {
+    final result = await _apiClient.stopBal(id);
+    _getBalsNoCache();
+    return result;
+  }
+
   Future<Result<Bal>> startBal(int id) async {
     if (isABalOngoing()) {
       return Result.error(

lib/data/services/api_client.dart

@@ -42,6 +42,33 @@ class ApiClient {
  * =================
 */
 
+  Future<Result<Bal>> stopBal(int id) async {
+    final client = Client();
+    try {
+      final headers = await _getHeaders();
+      final response = await client.post(
+        Uri.parse("https://$apiBasePath/bal/${id.toString()}/stop"),
+        headers: headers,
+      );
+      if (response.statusCode == 200) {
+        final json = jsonDecode(response.body);
+        return Result.ok(Bal.fromJSON(json));
+      } else if (response.statusCode == 403) {
+        throw "You don't own the specified BAL";
+      } else if (response.statusCode == 404) {
+        throw "No BAL with specified ID found";
+      } else if (response.statusCode == 409) {
+        throw "Selected BAL was not on ongoing state";
+      } else {
+        throw "Unknown error";
+      }
+    } catch (e) {
+      return Result.error(Exception(e));
+    } finally {
+      client.close();
+    }
+  }
+
   Future<Result<Bal>> startBal(int id) async {
     final client = Client();
     try {

lib/ui/bal_page/view_model/bal_view_model.dart

@@ -17,6 +17,18 @@ class BalViewModel extends ChangeNotifier {
   Bal? get bal => _bal;
   bool isABalOngoing = false;
 
+  Future<Result<void>> stopBal(int id) async {
+    final result = await _balRepository.stopBal(id);
+    switch (result) {
+      case Ok():
+        _bal = result.value;
+        notifyListeners();
+        break;
+      default:
+    }
+    return result;
+  }
+
   Future<Result<void>> startBal(int id) async {
     if (isABalOngoing) {
       return Result.error(Exception("Cannot have multiple BALs ongoing !"));

lib/ui/bal_page/widget/ongoing/bal_ongoing_screen.dart

@@ -12,7 +12,50 @@ class BalOngoingScreen extends StatelessWidget {
     return Scaffold(
       bottomNavigationBar: AppNavigationBar(startIndex: 0),
       appBar: AppBar(title: Text(viewModel.bal!.name)),
-      body: Center(child: Text("Ongoing BAL")),
+      body: Padding(
+        padding: const EdgeInsets.all(10.0),
+        child: Column(
+          children: [
+            Center(
+              child: ElevatedButton(
+                onPressed: () {
+                  showDialog(
+                    context: context,
+                    builder: (context) {
+                      return AlertDialog(
+                        title: Text(
+                          "Êtes-vous sûr·e de vouloir arrêter cette BAL ?",
+                        ),
+                        content: Text(
+                          "Cette action est irréversible. Vous pourrez ensuite consulter des statistiques sur la BAL, mais ne pourrez plus ajouter ou vendre de livre qui en fasse partie.",
+                        ),
+                        actions: [
+                          TextButton(
+                            onPressed: () {
+                              Navigator.of(context).pop();
+                            },
+                            child: Text("Annuler"),
+                          ),
+                          TextButton(
+                            onPressed: () async {
+                              await viewModel.stopBal(viewModel.bal!.id);
+                              if (context.mounted) {
+                                Navigator.of(context).pop();
+                              }
+                            },
+                            child: Text("Valider"),
+                          ),
+                        ],
+                      );
+                    },
+                  );
+                },
+                child: Text("Arrêter la BAL"),
+              ),
+            ),
+          ],
+        ),
+      ),
     );
   }
 }

lib/ui/bal_page/widget/pending/bal_pending_screen.dart

@@ -38,7 +38,36 @@ class BalPendingScreen extends StatelessWidget {
                   );
                 }
               : () {
-                  viewModel.startBal(viewModel.bal!.id);
+                  showDialog(
+                    context: context,
+                    builder: (context) {
+                      return AlertDialog(
+                        title: Text(
+                          "Êtes-vous sûr·e de vouloir débuter cette BAL ?",
+                        ),
+                        content: Text(
+                          "Cette action est irréversible. Vous pourrez ensuite intéragir avec la BAL, mais pas la remettre en mode \"À venir\"",
+                        ),
+                        actions: [
+                          TextButton(
+                            onPressed: () {
+                              Navigator.of(context).pop();
+                            },
+                            child: Text("Annuler"),
+                          ),
+                          TextButton(
+                            onPressed: () async {
+                              await viewModel.startBal(viewModel.bal!.id);
+                              if (context.mounted) {
+                                Navigator.of(context).pop();
+                              }
+                            },
+                            child: Text("Valider"),
+                          ),
+                        ],
+                      );
+                    },
+                  );
                 },
           child: Text("Démarrer cette BAL"),
         ),