from decimal import Decimal, InvalidOperation
import re


def parse_rub_amount(raw_value: str) -> Decimal | None:
    normalized_value = raw_value.lower().strip().replace(",", ".")
    normalized_value = normalized_value.replace(" ", "")
    normalized_value = re.sub(r"руб(лей|ля|ль|ле|\.?)", "", normalized_value)
    normalized_value = re.sub(r"[^\d.]", "", normalized_value)

    if not normalized_value or normalized_value.count(".") > 1:
        return None

    try:
        amount = Decimal(normalized_value)
    except InvalidOperation:
        return None

    if amount <= 0:
        return None

    if amount.as_tuple().exponent < -2:
        return None

    return amount.quantize(Decimal("0.01"))


def format_rub_amount(amount: Decimal) -> str:
    normalized_amount = amount.quantize(Decimal("0.01"))

    if normalized_amount == normalized_amount.to_integral():
        return f"{int(normalized_amount)} ₽"

    return f"{normalized_amount:.2f} ₽".replace(".", ",")