import random
import string


def _checksum(digits: str) -> int:
    return (97 - (int(digits) % 97)) % 97


def generer_rib(establishment_code: int, guichet_code: int) -> str:
    etab = str(establishment_code).zfill(5)
    guichet = str(guichet_code).zfill(5)
    numero = "".join(random.choices(string.digits, k=11))
    checksum_digits = f"76{etab}{guichet}{numero}"
    cle = str(_checksum(checksum_digits)).zfill(2)
    return f"FR76 {etab} {guichet} {numero} {cle}"


def valider_rib(rib: str) -> bool:
    parts = rib.replace("FR76 ", "").split()
    if len(parts) != 3:
        return False
    etab, guichet, rest = parts
    if len(etab) != 5 or len(guichet) != 5:
        return False
    if len(rest) != 13:
        return False
    numero = rest[:11]
    cle = rest[11:]
    if not etab.isdigit() or not guichet.isdigit() or not numero.isdigit() or not cle.isdigit():
        return False
    checksum_digits = f"76{etab}{guichet}{numero}"
    return _checksum(checksum_digits) == int(cle)


def decoder_rib(rib: str) -> dict:
    parts = rib.replace("FR76 ", "").split()
    if len(parts) != 3:
        return None
    etab, guichet, rest = parts
    numero = rest[:11]
    cle = rest[11:]
    etab_int = int(etab)
    guichet_int = int(guichet)

    TYPE_MAP = {4: "particulier", 3: "entreprise", 2: "banque", 1: "institution"}

    return {
        "etablissement": etab_int,
        "guichet": guichet_int,
        "numero": numero,
        "cle": int(cle),
        "type_compte": TYPE_MAP.get(guichet_int, "inconnu"),
        "est_gouvernement": etab_int < 100,
        "valide": valider_rib(rib),
    }