from typing import List, Optional

from ee.xml import types

__all__ = [
    "facts",
    "find_root_tag",
    "find_pn",
    "find_dpn",
]


def find_root_tag(root):
    return next((tag for tag, klass in types.GDSClassesMapping.items() if klass == type(root)), None)


def part_numbers(part: types.Part) -> List[types.PartNumber]:
    pns = part.part_numbersProp  # type: types.PartNumberList

    if pns is None:
        return []

    return pns.part_numberProp


def find_pn(part: types.Part) -> Optional[str]:
    for pn in part_numbers(part):
        if pn.distributor is None:
            return pn.value


def find_dpn(part: types.Part, distributor: str) -> Optional[str]:
    for pn in part_numbers(part):
        if pn.distributor == distributor:
            return pn.value


def facts(part: types.Part, create=False) -> Optional[types.FactList]:
    fs: types.FactList = part.factsProp

    if fs is not None:
        return fs

    if not create:
        return

    fs = types.FactList()
    part.factsProp = fs
    return fs