#!/usr/bin/env python3

r"""
Network generic functions.

"""

import gen_print as gp
import gen_cmd as gc
import gen_misc as gm
import var_funcs as vf
import collections
import re
import ipaddress
import subprocess
import socket
from robot.libraries.BuiltIn import BuiltIn
import json
import bmc_ssh_utils as bsu

ip_regex = r"\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}"


def get_running_system_ip():
    r"""
    Get the IP address of server from which robot code is running.

    """

    ip_list = list()
    stdout = subprocess.check_output(['hostname', '--all-fqdns'], shell=True)
    host_fqdns = stdout.decode("utf-8").strip()
    ip_address = socket.gethostbyname(str(host_fqdns))
    ip_list.append(ip_address)

    return ip_list


def netmask_prefix_length(netmask):
    r"""
    Return the netmask prefix length.

    Description of argument(s):
    netmask     Netmask value (e.g. "255.255.0.0", "255.255.255.0",
                                    "255.252.0.0", etc.).
    """

    # IP address netmask format: '0.0.0.0/255.255.252.0'
    return ipaddress.ip_network('0.0.0.0/' + netmask).prefixlen


def get_netmask_address(prefix_len):
    r"""
    Return the netmask address.

    Description of argument(s):
    prefix_len     Prefix length value (e.g. "24", "23", "22", etc.).
    """

    # IP address netmask format: '0.0.0.0/24'
    return ipaddress.ip_network('0.0.0.0/' + prefix_len).netmask


def parse_nping_output(output):
    r"""
    Parse the output from the nping command and return as a dictionary.

    Example of output value:

    Starting Nping 0.6.47 ( http://nmap.org/nping ) at 2019-08-07 22:05 IST
    SENT (0.0181s) TCP Source IP:37577 >
      Destination IP:80 S ttl=64 id=39113 iplen=40  seq=629782493 win=1480
    SENT (0.2189s) TCP Source IP:37577 >
      Destination IP:80 S ttl=64 id=39113 iplen=40  seq=629782493 win=1480
    RCVD (0.4120s) TCP Destination IP:80 >
      Source IP:37577 SA ttl=49 id=0 iplen=44  seq=1078301364 win=5840 <mss 1380>
    Max rtt: 193.010ms | Min rtt: 193.010ms | Avg rtt: 193.010ms
    Raw packets sent: 2 (80B) | Rcvd: 1 (46B) | Lost: 1 (50.00%)
    TCP connection attempts: 5 | Successful connections: 5 | Failed: 0 (0.00%)
    Nping done: 1 IP address pinged in 0.43 seconds

    Example of data returned by this function:

    nping_result:
      [max_rtt]:                 193.010ms
      [min_rtt]:                 193.010ms
      [avg_rtt]:                 193.010ms
      [raw_packets_sent]:        2 (80B)
      [rcvd]:                    1 (46B)
      [lost]:                    1 (50.00%)
      [percent_lost]:            50.00
      [tcp_connection_attempts]: 5
      [successful_connections]:  5
      [failed]:                  0 (0.00%)
      [percent_failed]:          0.00

    Description of argument(s):
    output                          The output obtained by running an nping
                                    command.
    """

    lines = output.split("\n")
    # Obtain only the lines of interest.
    lines = list(filter(lambda x: re.match(r"(Max rtt|Raw packets|TCP connection)", x),
                        lines))

    key_value_list = []
    for line in lines:
        key_value_list += line.split("|")
    nping_result = vf.key_value_list_to_dict(key_value_list)
    # Extract percent_lost/percent_failed value from lost/failed field.
    if 'lost' in nping_result:
        nping_result['percent_lost'] = \
            float(nping_result['lost'].split(" ")[-1].strip("()%"))
    else:
        nping_result['percent_failed'] = \
            float(nping_result['failed'].split(" ")[-1].strip("()%"))
    return nping_result


openbmc_host = BuiltIn().get_variable_value("${OPENBMC_HOST}")


def nping(host=openbmc_host, parse_results=1, **options):
    r"""
    Run the nping command and return the results either as a string or as a dictionary.

    Do a 'man nping' for a complete description of the nping utility.

    Note that any valid nping argument may be specified as a function argument.

    Example robot code:

    ${nping_result}=  Nping  delay=${delay}  count=${count}  icmp=${None}  icmp-type=echo
    Rprint Vars  nping_result

    Resulting output:

    nping_result:
      [max_rtt]:                                      0.534ms
      [min_rtt]:                                      0.441ms
      [avg_rtt]:                                      0.487ms
      [raw_packets_sent]:                             4 (112B)
      [rcvd]:                                         2 (92B)
      [lost]:                                         2 (50.00%)
      [percent_lost]:                                 50.0

    Description of argument(s):
    host                            The host name or IP of the target of the
                                    nping command.
    parse_results                   1 or True indicates that this function
                                    should parse the nping results and return
                                    a dictionary rather than the raw nping
                                    output.  See the parse_nping_output()
                                    function for details on the dictionary
                                    structure.
    options                         Zero or more options accepted by the nping
                                    command.  Do a 'man nping' for details.
    """

    command_string = gc.create_command_string('nping', host, options)
    rc, output = gc.shell_cmd(command_string, print_output=0, ignore_err=0)
    if parse_results:
        return parse_nping_output(output)

    return output


def get_channel_config():
    r"""
    Get the channel config data and return as a dictionary.

    Example:
    channel_config = get_channel_config()
    print_vars(channel_config)

    channel_config:
      [0]:
        [name]:                  IPMB
        [is_valid]:              True
        [active_sessions]:       0
        [channel_info]:
          [medium_type]:         ipmb
          [protocol_type]:       ipmb-1.0
          [session_supported]:   session-less
          [is_ipmi]:             True
      [1]:
        [name]:                  eth0
        [is_valid]:              True
        [active_sessions]:       0
        [channel_info]:
          [medium_type]:         other-lan
          [protocol_type]:       ipmb-1.0
          [session_supported]:   multi-session
          [is_ipmi]:             True
      [2]:
        [name]:                  eth1
        [is_valid]:              True
        [active_sessions]:       0
        [channel_info]:
          [medium_type]:         lan-802.3
          [protocol_type]:       ipmb-1.0
          [session_supported]:   multi-session
          [is_ipmi]:             True
    (etc.)
    """

    stdout, stderr, rc = bsu.bmc_execute_command("cat /usr/share/ipmi-providers/channel_config.json")
    return json.loads(stdout)


def get_active_channel_config():
    r"""
    Channel configs which medium_type are 'other-lan' or 'lan-802.3' returned by
     this function.
    """

    return vf.filter_struct(get_channel_config(), "[('medium_type', 'other-lan|lan-802.3')]", regex=1)


def get_channel_access_config(file_name):
    r"""
    Get the channel access config data and return as a dictionary.

    Description of argument:
    file_name     File name for channel access settings (e.g. '/run/ipmi/channel_access_volatile.json',
                 '/var/lib/ipmi/channel_access_nv.json'.).

    Example:

    channel_access_config =  get_channel_access_config()
    print_vars(channel_access_config)

    channel_access_config:
        [1]:
            [priv_limit]:                                 priv-admin
            [per_msg_auth_disabled]:                      False
            [access_mode]:                                always_available
            [alerting_disabled]:                          False
            [user_auth_disabled]:                         False
        [2]:
            [priv_limit]:                                 priv-admin
            [per_msg_auth_disabled]:                      False
            [access_mode]:                                always_available
            [alerting_disabled]:                          False
            [user_auth_disabled]:                         False
    """
    stdout, stderr, rc = bsu.bmc_execute_command("cat " + file_name)

    return json.loads(stdout)