import re
from typing import Tuple, Union

THERMAL_TRANSMITTANCE_U_VALUE_REGEX = re.compile(r"(\d+\.\d+)")
THERMAL_TRANSMITTANCE_UNIT_REGEX = re.compile(r"(w/m-¦k)")


def extract_thermal_transmittence(description_lower: str) -> Tuple[Union[float, None], Union[str, None]]:
    """
    Extracts thermal transmittance from the description.

    :param description_lower: Lowercase description.
    :return: Tuple containing U-value and unit.
    """
    # Find U-value
    u_value = re.search(THERMAL_TRANSMITTANCE_U_VALUE_REGEX, description_lower)
    if u_value is not None:
        u_value = float(u_value.group(1))
    else:
        u_value = None

    # Find unit
    unit = re.search(THERMAL_TRANSMITTANCE_UNIT_REGEX, description_lower)
    if unit is not None:
        unit = unit.group(1)
    else:
        unit = None

    return u_value, unit


def search_split_description(desc: str) -> str:
    """
    Searches split descriptions and looks for key words, determining a description about the roof's/floor's insulation.

    :param desc: Description to be searched.
    :return: Result of the search.
    """
    outputs = {
        "insulated": "average",
        "limited": "below average",
        "no insulation": "none",
        "limited insulation": "below average",
    }

    out = outputs.get(desc, None)

    if out:
        return out

    raise NotImplementedError("Handle me")