Κώδικας για ΠΑ και ΑΦΜ

afm-pa.py

# code utilities for Greek identifiers (ΑΦΜ and ΠΑ)
# Copyright (C) 2025 Alexios Zavras
# SPDX-License-Identifier: GPL-3.0-or-later


class ΑΦΜ:
    VALID_CHARS = set("0123456789")

    def __init__(self, value: str):
        self.value = value

    def __str__(self):
        return self.value

    def is_valid(self) -> bool:
        if len(self.value) != 9:
            return False
        if not all(c in self.VALID_CHARS for c in self.value):
            return False
        total = sum(int(self.value[8-i])*(1<<i) for i in range(1,9))
        check_digit = (total % 11) % 10
        return check_digit == int(self.value[8])


class ΠΑ:
    ALPHABET = "0123456789ΑΒΕΖΗΙΚΜΝΟΡΤΥΧ"

    def __init__(self, value: str):
        self.value = value

    def __str__(self):
        return self.value

    def is_valid(self, *, allow_latin:bool = False) -> bool:
        if len(self.value) != 12:
            return False
        if not ΑΦΜ(self.value[3:]).is_valid():
            return False
        s = self.value
        if allow_latin:
            s = s.translate(str.maketrans("ABEZHIKMNOPTYX", "ΑΒΕΖΗΙΚΜΝΟΡΤΥΧ"))
        if not all(c in self.ALPHABET for c in s):
            return False
        c2n = {c: i for i, c in enumerate(self.ALPHABET)}
        total = sum((c2n[s[i]] * (1 + i%2)) % 23 for i in range(12))
        return (total % 14) == 10



def gen_all_pa(afm: str, *, prefixes_only: bool = False):
    if not ΑΦΜ(afm).is_valid():
        raise ValueError("Invalid ΑΦΜ")
    c = sum(int(afm[i]) + (0 if i%2 else int(afm[i])) for i in range(9))
    for a, la in enumerate(ΠΑ.ALPHABET):
        for b, lb in enumerate(ΠΑ.ALPHABET):
            t = a + ((2*b) % 23) + c
            x = 10 + (-t % 14)
            lx = ΠΑ.ALPHABET[x]
            yield f"{la}{lb}{lx}" + ("" if prefixes_only else afm)