refactor: centralize settings and application services

assistant_bot/config.py

@@ -1,5 +1,6 @@
 import logging
 import os
+from dataclasses import dataclass
 from pathlib import Path
 from zoneinfo import ZoneInfo, ZoneInfoNotFoundError
 
@@ -46,6 +47,26 @@ MAX_AGENT_STEPS = 5
 CONVERSATION_HISTORY_LIMIT = 12
 
 
+@dataclass(frozen=True)
+class AppSettings:
+    bot_token: str
+    assistant_password: str
+    db_path: Path
+    mode: str
+    timezone: ZoneInfo
+    voice_max_duration_seconds: int
+    ollama_base_url: str
+    ollama_model: str
+    yandex_cloud_folder: str | None
+    yandex_cloud_model: str
+    yandex_stt_model: str
+    yandex_stt_language: str
+    whisper_model: str
+    whisper_device: str
+    whisper_compute_type: str
+    whisper_language: str | None
+
+
 def load_env_file(path: Path = ENV_FILE) -> None:
     if not path.exists():
         return
@@ -68,6 +89,128 @@ def load_env_file(path: Path = ENV_FILE) -> None:
         os.environ[key] = value
 
 
+def load_app_settings() -> AppSettings:
+    """Load and validate the complete startup configuration once."""
+    load_env_file()
+
+    token = os.getenv(TOKEN_ENV_NAME)
+    if not token:
+        raise RuntimeError(
+            f"Set {TOKEN_ENV_NAME} in environment or .env file."
+        )
+
+    password = os.getenv(PASSWORD_ENV_NAME, "").strip()
+    if not password:
+        raise RuntimeError(
+            f"Set {PASSWORD_ENV_NAME} in environment or .env file."
+        )
+
+    mode = os.getenv(MODE_ENV_NAME, DEFAULT_MODE).strip().lower()
+    if mode not in {"local", "yandex"}:
+        raise RuntimeError(
+            f"{MODE_ENV_NAME} must be either 'local' or 'yandex', got {mode!r}."
+        )
+
+    raw_db_path = os.getenv(DB_ENV_NAME)
+    if raw_db_path:
+        db_path = Path(raw_db_path).expanduser()
+        if not db_path.is_absolute():
+            db_path = PROJECT_ROOT / db_path
+    else:
+        db_path = DEFAULT_DB_FILE
+
+    timezone_name = os.getenv(TIMEZONE_ENV_NAME, DEFAULT_TIMEZONE)
+    try:
+        local_timezone = ZoneInfo(timezone_name)
+    except ZoneInfoNotFoundError:
+        logger.warning(
+            "Unknown timezone %s, falling back to UTC",
+            timezone_name,
+        )
+        local_timezone = ZoneInfo("UTC")
+
+    raw_voice_duration = os.getenv(
+        VOICE_MAX_DURATION_ENV_NAME,
+        str(DEFAULT_VOICE_MAX_DURATION_SECONDS),
+    )
+    try:
+        voice_duration = int(raw_voice_duration)
+    except ValueError:
+        voice_duration = 0
+    if voice_duration <= 0:
+        logger.warning(
+            "%s must be a positive integer, using %s",
+            VOICE_MAX_DURATION_ENV_NAME,
+            DEFAULT_VOICE_MAX_DURATION_SECONDS,
+        )
+        voice_duration = DEFAULT_VOICE_MAX_DURATION_SECONDS
+
+    yandex_folder = os.getenv(
+        YANDEX_CLOUD_FOLDER_ENV_NAME,
+        "",
+    ).strip().strip("/")
+    if mode == "yandex" and not yandex_folder:
+        raise RuntimeError(
+            f"Set {YANDEX_CLOUD_FOLDER_ENV_NAME} in environment or .env file."
+        )
+
+    yandex_model = os.getenv(
+        YANDEX_CLOUD_MODEL_ENV_NAME,
+        DEFAULT_YANDEX_CLOUD_MODEL,
+    ).strip().strip("/")
+    if not yandex_model:
+        yandex_model = DEFAULT_YANDEX_CLOUD_MODEL
+
+    whisper_language = os.getenv(
+        WHISPER_LANGUAGE_ENV_NAME,
+        DEFAULT_WHISPER_LANGUAGE,
+    ).strip()
+
+    return AppSettings(
+        bot_token=token,
+        assistant_password=password,
+        db_path=db_path,
+        mode=mode,
+        timezone=local_timezone,
+        voice_max_duration_seconds=voice_duration,
+        ollama_base_url=os.getenv(
+            OLLAMA_BASE_URL_ENV_NAME,
+            DEFAULT_OLLAMA_BASE_URL,
+        ).rstrip("/"),
+        ollama_model=os.getenv(
+            OLLAMA_MODEL_ENV_NAME,
+            DEFAULT_OLLAMA_MODEL,
+        ),
+        yandex_cloud_folder=yandex_folder or None,
+        yandex_cloud_model=yandex_model,
+        yandex_stt_model=os.getenv(
+            YANDEX_STT_MODEL_ENV_NAME,
+            DEFAULT_YANDEX_STT_MODEL,
+        ).strip(),
+        yandex_stt_language=os.getenv(
+            YANDEX_STT_LANGUAGE_ENV_NAME,
+            DEFAULT_YANDEX_STT_LANGUAGE,
+        ).strip(),
+        whisper_model=os.getenv(
+            WHISPER_MODEL_ENV_NAME,
+            DEFAULT_WHISPER_MODEL,
+        ).strip(),
+        whisper_device=os.getenv(
+            WHISPER_DEVICE_ENV_NAME,
+            DEFAULT_WHISPER_DEVICE,
+        ).strip(),
+        whisper_compute_type=os.getenv(
+            WHISPER_COMPUTE_TYPE_ENV_NAME,
+            DEFAULT_WHISPER_COMPUTE_TYPE,
+        ).strip(),
+        whisper_language=(
+            None
+            if whisper_language.lower() == "auto"
+            else whisper_language or None
+        ),
+    )
+
+
 def get_bot_token() -> str:
     load_env_file()
     token = os.getenv(TOKEN_ENV_NAME)