"""Geldbeträge werden intern immer als ganze Cent (int) geführt – keine Float-Rundungsfehler."""
from __future__ import annotations

from decimal import ROUND_HALF_UP, Decimal, InvalidOperation


def parse_cent(value) -> int:
    """Wandelt '1.234,56', '-8', '30', 12.5, '12.50 €' usw. in Cent um."""
    if value is None:
        return 0
    if isinstance(value, bool):
        raise ValueError("Ungültiger Betrag")
    if isinstance(value, int):
        return value * 100
    if isinstance(value, float):
        return int(Decimal(str(value)).scaleb(2).quantize(Decimal(1), ROUND_HALF_UP))
    s = str(value).strip().replace("€", "").replace("EUR", "").replace(" ", "").replace("\xa0", "")
    if not s:
        return 0
    neg = False
    if s.endswith("-"):  # SAP-Stil: '30,00-'
        neg, s = True, s[:-1]
    if "," in s and "." in s:
        if s.rfind(",") > s.rfind("."):
            s = s.replace(".", "").replace(",", ".")   # 1.234,56
        else:
            s = s.replace(",", "")                     # 1,234.56
    elif "," in s:
        s = s.replace(",", ".")
    try:
        d = Decimal(s)
    except InvalidOperation as exc:
        raise ValueError(f"Ungültiger Betrag: {value!r}") from exc
    cent = int(d.scaleb(2).quantize(Decimal(1), ROUND_HALF_UP))
    return -cent if neg else cent


def apply_percent(cent: int, prozent: float) -> int:
    d = Decimal(cent) * Decimal(str(prozent)) / Decimal(100)
    return int(d.quantize(Decimal(1), ROUND_HALF_UP))


def fmt(cent: int | None, symbol: bool = True) -> str:
    if cent is None:
        return ""
    neg = cent < 0
    cent = abs(cent)
    euro, rest = divmod(cent, 100)
    s = f"{euro:,}".replace(",", ".") + f",{rest:02d}"
    if neg:
        s = "-" + s
    return s + (" €" if symbol else "")


def to_euro(cent: int) -> float:
    return float(Decimal(cent) / Decimal(100))


def fmt_percent(p: float | None) -> str:
    if p is None:
        return ""
    s = f"{p:.2f}".rstrip("0").rstrip(".")
    return s.replace(".", ",") + " %"


def parse_percent(text: str) -> float:
    s = str(text).strip().replace("%", "").replace(" ", "").replace(",", ".")
    p = float(s)
    if p < 0 or p > 1000:
        raise ValueError("Prozentwert außerhalb des gültigen Bereichs")
    return p