Fix TOTP seed retrieval and auto index

README.md

@@ -179,7 +179,7 @@ python src/main.py
 
 1. From the main menu choose **Add Entry** and select **2FA (TOTP)**.
 2. Provide a label for the account (for example, `GitHub`).
-3. Enter the derivation index you wish to use for this 2FA code.
+3. SeedPass automatically chooses the next available derivation index.
 4. Optionally specify the TOTP period and digit count.
 5. SeedPass will display an `otpauth://` URI and secret that you can manually
    enter into your authenticator app.

src/password_manager/entry_management.py

@@ -153,11 +153,29 @@ class EntryManager:
             print(colored(f"Error: Failed to add entry: {e}", "red"))
             sys.exit(1)
 
+    def get_next_totp_index(self) -> int:
+        """Return the next available derivation index for TOTP secrets."""
+        data = self.vault.load_index()
+        entries = data.get("entries", {})
+        indices = [
+            int(v.get("index", 0))
+            for v in entries.values()
+            if v.get("type") == EntryType.TOTP.value
+        ]
+        return (max(indices) + 1) if indices else 0
+
     def add_totp(
-        self, label: str, index: int, period: int = 30, digits: int = 6
+        self,
+        label: str,
+        parent_seed: str,
+        index: int | None = None,
+        period: int = 30,
+        digits: int = 6,
     ) -> str:
         """Add a new TOTP entry and return the provisioning URI."""
         entry_id = self.get_next_index()
+        if index is None:
+            index = self.get_next_totp_index()
         data = self.vault.load_index()
         data.setdefault("entries", {})
 
@@ -174,8 +192,7 @@ class EntryManager:
         self.backup_index_file()
 
         try:
-            seed = self.vault.encryption_manager.decrypt_parent_seed()
+            secret = TotpManager.derive_secret(parent_seed, index)
-            secret = TotpManager.derive_secret(seed, index)
             return TotpManager.make_otpauth_uri(label, secret, period, digits)
         except Exception as e:
             logger.error(f"Failed to generate otpauth URI: {e}")
@@ -203,15 +220,16 @@ class EntryManager:
         self.backup_index_file()
         raise NotImplementedError("Seed entry support not implemented yet")
 
-    def get_totp_code(self, index: int, timestamp: int | None = None) -> str:
+    def get_totp_code(
+        self, index: int, parent_seed: str, timestamp: int | None = None
+    ) -> str:
         """Return the current TOTP code for the specified entry."""
         entry = self.retrieve_entry(index)
         if not entry or entry.get("type") != EntryType.TOTP.value:
             raise ValueError("Entry is not a TOTP entry")
 
-        seed = self.vault.encryption_manager.decrypt_parent_seed()
         totp_index = int(entry.get("index", 0))
-        return TotpManager.current_code(seed, totp_index, timestamp)
+        return TotpManager.current_code(parent_seed, totp_index, timestamp)
 
     def get_totp_time_remaining(self, index: int) -> int:
         """Return seconds remaining in the TOTP period for the given entry."""

src/password_manager/manager.py

@@ -870,11 +870,7 @@ class PasswordManager:
                 print(colored("Error: Label cannot be empty.", "red"))
                 return
 
-            index_input = input("Enter derivation index (number): ").strip()
+            totp_index = self.entry_manager.get_next_totp_index()
-            if not index_input.isdigit():
-                print(colored("Error: Index must be a number.", "red"))
-                return
-            totp_index = int(index_input)
 
             period_input = input("TOTP period in seconds (default 30): ").strip()
             period = 30
@@ -893,7 +889,13 @@ class PasswordManager:
                 digits = int(digits_input)
 
             entry_id = self.entry_manager.get_next_index()
-            uri = self.entry_manager.add_totp(label, totp_index, period, digits)
+            uri = self.entry_manager.add_totp(
+                label,
+                self.parent_seed,
+                index=totp_index,
+                period=period,
+                digits=digits,
+            )
 
             self.is_dirty = True
             self.last_update = time.time()

src/tests/test_entry_add.py

@@ -52,8 +52,7 @@ def test_round_trip_entry_types(method, expected_type):
         if method == "add_entry":
             index = entry_mgr.add_entry("example.com", 8)
         elif method == "add_totp":
-            with patch.object(enc_mgr, "decrypt_parent_seed", return_value=TEST_SEED):
+            entry_mgr.add_totp("example", TEST_SEED)
-                entry_mgr.add_totp("example", 0)
             index = 0
         else:
             with pytest.raises(NotImplementedError):

src/tests/test_totp_entry.py

@@ -19,8 +19,7 @@ def test_add_totp_and_get_code():
         vault, enc_mgr = create_vault(Path(tmpdir), TEST_SEED, TEST_PASSWORD)
         entry_mgr = EntryManager(vault, Path(tmpdir))
 
-        with patch.object(enc_mgr, "decrypt_parent_seed", return_value=TEST_SEED):
+        uri = entry_mgr.add_totp("Example", TEST_SEED)
-            uri = entry_mgr.add_totp("Example", 0)
         assert uri.startswith("otpauth://totp/")
 
         entry = entry_mgr.retrieve_entry(0)
@@ -32,8 +31,7 @@ def test_add_totp_and_get_code():
             "digits": 6,
         }
 
-        with patch.object(enc_mgr, "decrypt_parent_seed", return_value=TEST_SEED):
+        code = entry_mgr.get_totp_code(0, TEST_SEED, timestamp=0)
-            code = entry_mgr.get_totp_code(0, timestamp=0)
 
         expected = TotpManager.current_code(TEST_SEED, 0, timestamp=0)
         assert code == expected
@@ -44,8 +42,7 @@ def test_totp_time_remaining(monkeypatch):
         vault, enc_mgr = create_vault(Path(tmpdir), TEST_SEED, TEST_PASSWORD)
         entry_mgr = EntryManager(vault, Path(tmpdir))
 
-        with patch.object(enc_mgr, "decrypt_parent_seed", return_value=TEST_SEED):
+        entry_mgr.add_totp("Example", TEST_SEED)
-            entry_mgr.add_totp("Example", 0)
 
         monkeypatch.setattr(TotpManager, "time_remaining", lambda period: 7)
         remaining = entry_mgr.get_totp_time_remaining(0)