#
# Copyright (C) 2022 Soleta Networks <info@soleta.eu>
#
# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the
# Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.

import array
import fcntl
import socket
import struct
import psutil
import logging

def is_ethernet(interface):
    SIOCGIFHWADDR = 0x8927
    ARPHRD_ETHER = 1

    try:
        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        info = fcntl.ioctl(
            s.fileno(),
            SIOCGIFHWADDR,
            struct.pack('256s', interface.encode('utf-8')[:15]))
        if struct.unpack('H', info[16:18])[0] == ARPHRD_ETHER:
            return True
        return False
    except IOError:
        return False
    finally:
        s.close()

def is_wifi(interface):
    SIOCGIWNAME = 0x8B01  # Wireless-specific ioctl

    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    try:
        buffer = struct.pack('256s', interface.encode('utf-8'))
        info = fcntl.ioctl(sock.fileno(), SIOCGIWNAME, buffer)
        return True
    except IOError:
        return False
    finally:
        sock.close()

def is_link_active(interface):
    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

    try:
        # Get interface flags
        ifreq = struct.pack('16sh', interface.encode('utf-8'), 0)
        flags = struct.unpack('16sh', fcntl.ioctl(sock.fileno(), 0x8913, ifreq))[1]

        # Check if IFF_UP and IFF_RUNNING flags are set
        if flags & 0x1 and flags & 0x40:
            return True
        else:
            return False
    except IOError:
        return False
    finally:
        sock.close()

def get_ethernet_interface():
    eth_interfaces = []
    interfaces = psutil.net_if_addrs()
    for interface in interfaces:
        if is_ethernet(interface) and not is_wifi(interface) and is_link_active(interface):
            eth_interfaces.append(interface)

    if len(eth_interfaces) > 1:
        logging.info(f'Multiple active ethernet interfaces found: {", ".join(eth_interfaces)}. Using {eth_interfaces[0]}')

    if not eth_interfaces:
        logging.info('No valid ethernet interface found')
        return None

    return eth_interfaces[0]

def ethtool(interface):
    try:
        ETHTOOL_GSET = 0x00000001
        SIOCETHTOOL = 0x8946
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        sockfd = sock.fileno()
        ecmd = array.array(
                "B", struct.pack("I39s", ETHTOOL_GSET, b"\x00" * 39)
               )
        interface = interface.encode("utf-8")
        ifreq = struct.pack("16sP", interface, ecmd.buffer_info()[0])
        fcntl.ioctl(sockfd, SIOCETHTOOL, ifreq)
        res = ecmd.tobytes()
        speed = struct.unpack("12xH29x", res)[0]
    except IOError:
        speed = 0
    finally:
        sock.close()
    return speed

def getifaddr(device):
    """
    """
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    return socket.inet_ntoa(fcntl.ioctl(
        s.fileno(),
        0x8915,  # SIOCGIFADDR
        struct.pack('256s', bytes(device[:15], 'utf-8'))
    )[20:24])

def getifhwaddr(device):
    """
    """
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    hwaddr = fcntl.ioctl(
        s.fileno(),
        0x8927,  # SIOCGIFHWADDR
        struct.pack('256s', bytes(device[:15], 'utf-8'))
        )[18:24]
    return "%02x:%02x:%02x:%02x:%02x:%02x" % struct.unpack("BBBBBB", hwaddr)