Refactor VM registration process in VmUpdater (#314)

* Refactor VM registration process in VmUpdater

- Enhanced the VM registration logic to first check if the VM is already registered, logging a message if it is. This change improves the clarity of the registration process.
- Updated the handling of the VBox file to ensure it exists before proceeding with registration, enhancing error handling and robustness in the VM management workflow.

* Refactor VM registration in VmUpdater

- Streamlined the VM registration process by directly passing the VBox file path to the `_remove_useless_dvd_images` and `register` methods, enhancing code clarity and reducing redundancy.
- This change improves the overall efficiency of the VM update workflow.

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Co-authored-by: Nikolai Lambrov <[email protected]>

Author: l8556

frameworks/vm_manager/vm_updater.py

@@ -306,13 +306,18 @@ def _register_vm(self) -> None:
         """
         Register VM in VirtualBox.
         """
-        if not self.vm.is_registered():
-            vbox_file = self._find_vbox_file()
-            if vbox_file and vbox_file.is_file():
-                self._remove_useless_dvd_images(config_path=str(vbox_file))
-                self.vm.register(str(vbox_file))
-            else:
-                self._log(f"VBox file not found on path: [cyan]{self.vm_dir}[/cyan]", color='red')
+        if self.vm.is_registered():
+            self._log(f"VM [cyan]{self.vm.name}[/cyan] is already registered", color='green')
+            self._remove_useless_dvd_images()
+            return
+
+        vbox_file = self._find_vbox_file()
+        if not (vbox_file and vbox_file.is_file()):
+            self._log(f"VBox file not found on path: [cyan]{self.vm_dir}[/cyan]", color='red')
+            return
+
+        self._remove_useless_dvd_images(config_path=str(vbox_file))
+        self.vm.register(str(vbox_file))
 
     def _move_to_group_dir(self) -> None:
         """