"""Только чтение: адреса сети и broadcast, уже записанные в БД (IPv4, префикс ≤ /30). Запуск: venv/bin/python scripts/find_unusable_addresses.py"""
import ipaddress
import pathlib

import psycopg

env = dict(l.split("=", 1) for l in pathlib.Path(__file__).resolve().parent.parent.joinpath(".env").read_text().split() if "=" in l)
dsn = f"postgresql://{env['POSTGRES_USER']}:{env['POSTGRES_PASSWORD']}@127.0.0.1:{env['DB_HOST_PORT']}/{env['POSTGRES_DB']}"
with psycopg.connect(dsn) as conn:
    rows = conn.execute("SELECT a.id, host(a.address), p.prefix::text, o.name FROM addresses a JOIN prefixes p ON p.id = a.prefix_id JOIN organizations o ON o.id = p.organization_id ORDER BY a.id").fetchall()
found = 0
for aid, ip, cidr, org in rows:
    net, addr = ipaddress.ip_network(cidr), ipaddress.ip_address(ip)
    if net.version == 4 and net.prefixlen <= 30 and addr in (net.network_address, net.broadcast_address):
        found += 1
        print(f"address id={aid}  {ip}  в {cidr}  ({org})  — {'адрес сети' if addr == net.network_address else 'broadcast'}")
print(f"найдено: {found}")