from datetime import date, datetime


def format_money(value: float | int | None) -> str:
    """Return money value in a readable Russian format."""
    amount = 0 if value is None else float(value)
    return f"{amount:,.2f} ₽".replace(",", " ")


def current_month_key() -> str:
    """Return current month in SQLite-friendly format YYYY-MM."""
    return date.today().strftime("%Y-%m")


def today_text() -> str:
    """Return current date in ISO format for entry fields."""
    return date.today().strftime("%Y-%m-%d")


def validate_date(value: str) -> str:
    """Validate user date and return normalized ISO date."""
    try:
        return datetime.strptime(value.strip(), "%Y-%m-%d").strftime("%Y-%m-%d")
    except ValueError as error:
        raise ValueError("Дата должна быть в формате ГГГГ-ММ-ДД.") from error