import subprocess

def detect_rt_tables_path():
    return "/etc/iproute2/rt_tables"

def list_connections():
    output = subprocess.check_output(["nmcli", "-t", "-f", "uuid,name,type,device", "connection", "show"]).decode()
    print("\n[DEBUG] Surowe dane z nmcli:")
    print(output)

    conns = []
    for line in output.strip().splitlines():
        parts = line.strip().split(":", 3)
        if len(parts) < 4:
            continue
        uuid, name, typ, dev = parts
        if typ.strip() in ["ethernet", "802-3-ethernet"]:
            dev = dev.strip() if dev.strip() else "<brak>"
            conns.append({"uuid": uuid, "name": name, "device": dev})
    return conns

def prompt_config(conn):
    default_iface = conn['device']
    if not default_iface:
        default_iface = input(f"Podaj nazwę interfejsu dla połączenia '{conn['name']}' ({conn['uuid']}): ").strip()

    print(f"\n--- Konfiguracja dla interfejsu: {default_iface} ({conn['name']}) ---")
    ip = input("Adres IP/maska (np. 10.87.2.121/24): ").strip()

    # domyślna brama z IP
    ip_parts = ip.split(".")
    default_gw = f"{ip_parts[0]}.{ip_parts[1]}.{ip_parts[2]}.1" if len(ip_parts) >= 4 else ""

    gw_input = input(f"Brama (enter = brak, d = {default_gw}): ").strip().lower()
    if gw_input == "d":
        gw = default_gw
    elif gw_input == "":
        gw = None
    else:
        gw = gw_input

    third_octet = ip_parts[2] if len(ip_parts) >= 3 else "100"
    default_table = third_octet
    default_prio = third_octet

    table = input(f"Numer tablicy routingu [domyślnie {default_table}]: ").strip() or default_table
    prio = input(f"Priorytet dla rule [domyślnie {default_prio}]: ").strip() or default_prio

    return {
        "uuid": conn["uuid"],
        "iface": default_iface,
        "ip": ip,
        "gateway": gw,
        "table": table,
        "priority": prio
    }

def ask_disable_ipv6(devices):
    choice = input("\nWyłączyć IPv6? (tak/wszystkie/nie/[lista interfejsów oddzielona spacją]): ").strip().lower()
    if choice in ["tak", "yes", "y", "wszystkie"]:
        return set(devices)
    elif choice in ["nie", "no", "n"]:
        return set()
    else:
        return set(choice.split())

def ask_main_gateway_iface(devices):
    print("\nDostępne interfejsy: " + ", ".join(devices))
    main_iface = input("Podaj nazwę interfejsu, który ma mieć bramę główną (main), enter jeśli żaden: ").strip()
    return main_iface if main_iface in devices else None

def generate_commands(configs, disable_ipv6_ifaces, main_iface):
    lines = []
    rt_tables = set()

    for c in configs:
        uuid = c["uuid"]
        iface = c["iface"]
        ip = c["ip"]
        gateway = c["gateway"]
        table = c["table"]
        priority = c["priority"]

        lines.append(f"# Konfiguracja: {iface} ({uuid}) → {ip} gw {gateway or '-'} table {table}")

        # Ustawienia podstawowe
        lines.append(f"nmcli con modify {uuid} connection.interface-name {iface}")
        lines.append(f"nmcli con modify {uuid} ipv4.addresses {ip} ipv4.method manual")
        lines.append(f"nmcli con modify {uuid} ipv4.never-default yes")

        # IPv6 wyłączony jeśli wskazano
        if iface in disable_ipv6_ifaces:
            lines.append(f"nmcli con modify {uuid} ipv6.method ignore")

        # Parsowanie adresu IP bez maski
        ip_only = ip.split("/")[0]

        # Obsługa tras i reguł tylko jeśli podano bramę
        if gateway:
            if iface == main_iface:
                # tylko tu ustawiamy bramę domyślną
                lines.append(f"nmcli con modify {uuid} ipv4.gateway {gateway}")
            else:
                # trasa i reguła do osobnej tablicy
                lines.append(f"nmcli con modify {uuid} +ipv4.routes \"0.0.0.0/0 {gateway} table={table}\"")
                lines.append(f"nmcli con modify {uuid} ipv4.routing-rules \"priority {priority} from {ip_only}/32 table {table}\"")
                rt_tables.add(f"{table} rt{table}")

        lines.append("")  # pusta linia dla czytelności

    # Restart połączeń
    lines.append("# Restart połączeń")
    for c in configs:
        lines.append(f"nmcli con down {c['uuid']} || true")
        lines.append(f"nmcli con up {c['uuid']}")

    # Dodaj wpisy do rt_tables tylko dla użytych tablic
    rt_path = detect_rt_tables_path()
    lines.append(f"\n# Wpisy do {rt_path}")
    if "rt_tables.d" in rt_path:
        lines.append("mkdir -p /etc/iproute2/rt_tables.d")
    for rt in sorted(rt_tables):
        lines.append(f"echo \"{rt}\" | sudo tee -a {rt_path} > /dev/null")

    return "\n".join(lines)


def main():
    connections = list_connections()

    print("\n[DEBUG] Wykryto połączenia:")
    for c in connections:
        print(f"- {c['name']} ({c['uuid']}) → {c['device']}")

    if len(connections) == 0:
        print("Brak połączeń ethernet.")
        return

    devices = [c["device"] for c in connections]
    disable_ipv6_ifaces = ask_disable_ipv6(devices)
    main_iface = ask_main_gateway_iface(devices)
    configs = [prompt_config(c) for c in connections]
    result = generate_commands(configs, disable_ipv6_ifaces, main_iface)

    print("\n=== Wygenerowane polecenia ===\n")
    print(result)

    with open("nmcli_setup.sh", "w") as f:
        f.write(result)
    print("\nZapisano do pliku: nmcli_setup.sh")

if __name__ == "__main__":
    main()