"""Access value serialization helpers.

Converts pyodbc/Access cell values into JSON-serializable Python types so a
captured row dict can be ``json.dumps``-ed before being enqueued on SQL Server.

Order matters: ``bool`` MUST be checked before ``int`` because ``bool`` is a
subclass of ``int`` in Python (``isinstance(True, int) is True``). If the order
were reversed, ``True`` would be returned as ``1`` and lose its type.
"""
import datetime
import decimal


def to_jsonable(v):
    """Coerce a single Access/pyodbc value to a JSON-serializable form.

    - ``None`` -> ``None``
    - ``bool`` -> ``bool`` (must precede the ``int`` branch)
    - ``datetime``/``date`` -> ISO-8601 string (``"2026-07-14T08:41:18"``)
    - ``Decimal`` -> string (preserves exact scale, e.g. ``"12.50"``)
    - ``int``/``float``/``str`` -> unchanged
    - anything else (e.g. ``bytes`` for OLE) -> ``str(v)`` fallback
    """
    if v is None:
        return None
    if isinstance(v, bool):              # MUST be before int
        return v
    if isinstance(v, (datetime.datetime, datetime.date)):
        return v.isoformat()
    if isinstance(v, decimal.Decimal):
        return str(v)
    if isinstance(v, (int, float, str)):
        return v
    return str(v)