import os
from dataclasses import dataclass
from pathlib import Path


def _database_file_values() -> dict[str, str]:
    """Read the project's existing database note without copying credentials."""
    path = Path(__file__).resolve().parents[2] / "数据库.md"
    if not path.exists():
        return {}
    values: dict[str, str] = {}
    for line in path.read_text(encoding="utf-8").splitlines():
        if ":" in line:
            key, value = line.split(":", 1)
        elif "=" in line:
            key, value = line.split("=", 1)
        else:
            continue
        values[key.strip().lower()] = value.strip()
    return values


_database_values = _database_file_values()


@dataclass(frozen=True)
class Settings:
    # Keep credentials outside the source tree. DEMO_MODE defaults to "never":
    # a database failure raises an error instead of silently serving demo data.
    # Use DEMO_MODE=always for demo data, or DEMO_MODE=auto for fallback.
    db_host: str = os.getenv("DB_HOST", _database_values.get("host", "127.0.0.1"))
    db_port: int = int(os.getenv("DB_PORT", _database_values.get("port", "3306")))
    db_user: str = os.getenv("DB_USER", _database_values.get("user", "root"))
    db_password: str = os.getenv("DB_PASSWORD", _database_values.get("password", ""))
    db_name: str = os.getenv("DB_NAME", _database_values.get("db_name", "compressorsensor"))
    db_connect_timeout: int = int(os.getenv("DB_CONNECT_TIMEOUT", "3"))
    demo_mode: str = os.getenv("DEMO_MODE", "never").strip().lower()
    cors_origin: str = os.getenv("CORS_ORIGIN", "http://localhost:5173")
    annotation_width: int = int(os.getenv("ANNOTATION_WIDTH", "10"))
    auth_user: str = os.getenv("AUTH_USER", "aaabbb")
    auth_password: str = os.getenv("AUTH_PASSWORD", "Aa*147258&cd")
    auth_token_ttl_seconds: int = int(os.getenv("AUTH_TOKEN_TTL_SECONDS", "43200"))


settings = Settings()