feat: add dynamic owner binding

tests/test_dynamic_whitelist.py

@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+# Copyright (C) 2026 Alexey
+
+from __future__ import annotations
+
+import os
+from pathlib import Path
+from unittest.mock import MagicMock
+
+from telegram import Update, User
+
+from miband_tracker.bot import app
+from miband_tracker.config import Settings
+
+
+def test_dynamic_whitelisting(tmp_path: Path) -> None:
+    # Setup temporary directories and config
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+
+    # Override settings in app and os.environ
+    os.environ["DATA_DIR"] = str(data_dir)
+    os.environ["TELEGRAM_ALLOWED_USER_ID"] = ""
+
+    app.SETTINGS = Settings.from_env()
+    app.ALLOWED_USER_ID = None
+
+    # Verify initial state
+    assert app.ALLOWED_USER_ID is None
+    assert not (data_dir / "allowed_user.id").exists()
+
+    # 1. First user tries to access
+    user_1 = MagicMock(spec=User)
+    user_1.id = 999999
+    update_1 = MagicMock(spec=Update)
+    update_1.effective_user = user_1
+
+    # First access should be allowed and should bind user_1
+    assert app.is_allowed(update_1) is True
+    assert app.ALLOWED_USER_ID == 999999
+    assert (data_dir / "allowed_user.id").exists()
+    assert (data_dir / "allowed_user.id").read_text(encoding="utf-8").strip() == "999999"
+
+    # 2. Second user tries to access
+    user_2 = MagicMock(spec=User)
+    user_2.id = 888888
+    update_2 = MagicMock(spec=Update)
+    update_2.effective_user = user_2
+
+    # Access for user_2 must be blocked
+    assert app.is_allowed(update_2) is False
+
+    # 3. First user accesses again
+    assert app.is_allowed(update_1) is True
+
+    # 4. Verify settings reloading
+    reloaded_settings = Settings.from_env()
+    assert reloaded_settings.telegram_allowed_user_id == 999999