Prompt before overwriting an existing key file, with option to rename

keygen.py

@@ -72,6 +72,29 @@ def format_mnemonic(words: str) -> str:
     return "\n".join(lines)
 
 
+def resolve_output_path(requested: Path) -> Path:
+    """Return the path to write to, prompting if the file already exists."""
+    path = requested
+    while path.exists():
+        print(f"File already exists: {path}")
+        print("  [o] Overwrite  [r] Rename  [q] Quit")
+        choice = input("Choice: ").strip().lower()
+        if choice == "o":
+            break
+        elif choice == "r":
+            new_name = input(f"New filename (in {path.parent}): ").strip()
+            if not new_name:
+                print("No name entered, try again.")
+                continue
+            path = path.parent / new_name
+        elif choice == "q":
+            print("Aborted.")
+            sys.exit(0)
+        else:
+            print("Please enter o, r, or q.")
+    return path
+
+
 def ask_passphrase(confirm: bool = True) -> bytes | None:
     passphrase = getpass.getpass("Key passphrase (leave blank for none): ")
     if not passphrase:
@@ -93,7 +116,7 @@ def cmd_generate(args: argparse.Namespace) -> None:
 
     passphrase = ask_passphrase(confirm=True) if args.passphrase else None
 
-    output = Path(args.output)
+    output = resolve_output_path(Path(args.output))
     key_path, pub_path = save_keypair(private_key, output, args.comment, passphrase)
 
     print(f"\nGenerated Ed25519 SSH key pair")
@@ -129,7 +152,7 @@ def cmd_recover(args: argparse.Namespace) -> None:
 
     passphrase = ask_passphrase(confirm=True) if args.passphrase else None
 
-    output = Path(args.output)
+    output = resolve_output_path(Path(args.output))
     key_path, pub_path = save_keypair(private_key, output, args.comment, passphrase)
 
     print(f"\nRecovered Ed25519 SSH key pair")