from app.core.config import get_settings


class OperationsDisabledError(RuntimeError):
    """Raised when a business mutation is attempted in read-only mode."""


def business_mutations_enabled() -> bool:
    """Return whether platform-owned business ledgers may be mutated."""

    return not get_settings().read_only_mode


def ensure_business_mutations_enabled() -> None:
    """Enforce read-only policy outside the HTTP transport layer."""

    if not business_mutations_enabled():
        raise OperationsDisabledError(
            "Business mutations are disabled while READ_ONLY_MODE is enabled"
        )