adding CityWallet functionality

lib/screens/confirm/confirm_screen.dart

@@ -78,6 +78,41 @@ class _ConfirmScreenState extends State<ConfirmScreen>
 
       if (!mounted) return;
 
+      // Check if the selected payment processor is a wallet (e.g. Velocity)
+      if (controller
+              .transactionController
+              .model
+              .selectedPaymentProcessor
+              .label ==
+          'WALLET') {
+        final otp = await _showOtpBottomSheet();
+        if (otp == null) return; // User cancelled or dismissed the bottom sheet
+
+        if (!mounted) return;
+
+        final transactionId =
+            controller.transactionController.model.confirmationData['id'];
+        final otpResponse = await controller.updateVelocityTransactionOtp(
+          transactionId,
+          {'verificationCode': otp},
+        );
+
+        if (!otpResponse.isSuccess) {
+          if (context.mounted) {
+            AppSnackBar.showError(
+              context,
+              controller.model.errorMessage ??
+                  otpResponse.error ??
+                  "OTP verification failed",
+            );
+          }
+          return;
+        }
+
+        if (!mounted) return;
+      }
+
+      // Proceed with normal flow after OTP step (or skip if not WALLET)
       if (controller
               .transactionController
               .model
@@ -99,6 +134,101 @@ class _ConfirmScreenState extends State<ConfirmScreen>
     }
   }
 
+  Future<String?> _showOtpBottomSheet() {
+    final otpController = TextEditingController();
+    final formKey = GlobalKey<FormState>();
+
+    return showModalBottomSheet<String>(
+      context: context,
+      isDismissible: false,
+      enableDrag: false,
+      shape: const RoundedRectangleBorder(
+        borderRadius: BorderRadius.vertical(top: Radius.circular(20)),
+      ),
+      builder: (context) {
+        return Padding(
+          padding: EdgeInsets.only(
+            left: 24,
+            right: 24,
+            top: 24,
+            bottom: MediaQuery.of(context).viewInsets.bottom + 24,
+          ),
+          child: Form(
+            key: formKey,
+            child: Column(
+              mainAxisSize: MainAxisSize.min,
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Center(
+                  child: Container(
+                    width: 40,
+                    height: 4,
+                    decoration: BoxDecoration(
+                      color: Colors.grey.shade300,
+                      borderRadius: BorderRadius.circular(2),
+                    ),
+                  ),
+                ),
+                const SizedBox(height: 20),
+                Text(
+                  'OTP Verification',
+                  style: TextStyle(
+                    fontSize: 20,
+                    fontWeight: FontWeight.bold,
+                    color: Theme.of(context).colorScheme.primary,
+                  ),
+                ),
+                const SizedBox(height: 8),
+                Text(
+                  'Please enter the OTP sent to your mobile/email',
+                  style: TextStyle(fontSize: 14, color: Colors.grey.shade600),
+                ),
+                const SizedBox(height: 20),
+                TextFormField(
+                  controller: otpController,
+                  keyboardType: TextInputType.number,
+                  decoration: InputDecoration(
+                    labelText: 'Enter OTP',
+                    border: OutlineInputBorder(
+                      borderRadius: BorderRadius.circular(12),
+                    ),
+                  ),
+                  validator: (value) {
+                    if (value == null || value.trim().isEmpty) {
+                      return 'Please enter the OTP';
+                    }
+                    return null;
+                  },
+                ),
+                const SizedBox(height: 20),
+                SizedBox(
+                  width: double.infinity,
+                  child: ElevatedButton(
+                    onPressed: () {
+                      if (formKey.currentState!.validate()) {
+                        Navigator.of(context).pop(otpController.text.trim());
+                      }
+                    },
+                    style: ElevatedButton.styleFrom(
+                      padding: const EdgeInsets.symmetric(vertical: 16),
+                      shape: RoundedRectangleBorder(
+                        borderRadius: BorderRadius.circular(12),
+                      ),
+                    ),
+                    child: const Text(
+                      'Submit OTP',
+                      style: TextStyle(fontSize: 16),
+                    ),
+                  ),
+                ),
+              ],
+            ),
+          ),
+        );
+      },
+    );
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(