"""
Copyright (c) 2017 Wind River Systems, Inc.

SPDX-License-Identifier: Apache-2.0

"""

import json
import netaddr
import os
import subprocess
import sys
import time

import configutilities.common.exceptions as cexeptions
import configutilities.common.utils as cutils


def is_valid_management_address(ip_address, management_subnet):
    """Determine whether a management address is valid."""
    if ip_address == management_subnet.network:
        print "Cannot use network address"
        return False
    elif ip_address == management_subnet.broadcast:
        print "Cannot use broadcast address"
        return False
    elif ip_address.is_multicast():
        print "Invalid address - multicast address not allowed"
        return False
    elif ip_address.is_loopback():
        print "Invalid address - loopback address not allowed"
        return False
    elif ip_address not in management_subnet:
        print "Address must be in the management subnet"
        return False
    else:
        return True


def configure_management():
    interface_list = list()
    lldp_interface_list = list()

    print "Enabling interfaces... ",
    ip_link_output = subprocess.check_output(['ip', '-o', 'link'])

    for line in ip_link_output.splitlines():
        interface = line.split()[1].rstrip(':')
        if interface != 'lo':
            interface_list.append(interface)
        subprocess.call(['ip', 'link', 'set', interface, 'up'])
    print 'DONE'

    wait_seconds = 120
    delay_seconds = 5
    print "Waiting %d seconds for LLDP neighbor discovery" % wait_seconds,
    while wait_seconds > 0:
        sys.stdout.write('.')
        sys.stdout.flush()
        time.sleep(delay_seconds)
        wait_seconds -= delay_seconds
    print ' DONE'

    print "Retrieving neighbor details... ",
    lldpcli_show_output = subprocess.check_output(
        ['sudo', 'lldpcli', 'show', 'neighbors', 'summary', '-f', 'json'])
    lldp_interfaces = json.loads(lldpcli_show_output)['lldp'][0]['interface']
    print "DONE"

    print "\nAvailable interfaces:"
    print "%-20s %s" % ("local interface", "remote port")
    print "%-20s %s" % ("---------------", "-----------")
    for interface in lldp_interfaces:
        print "%-20s %s" % (interface['name'],
                            interface['port'][0]['id'][0]['value'])
        lldp_interface_list.append(interface['name'])
    for interface in interface_list:
        if interface not in lldp_interface_list:
            print "%-20s %s" % (interface, 'unknown')

    print
    while True:
        user_input = raw_input("Enter management interface name: ")
        if user_input in interface_list:
            management_interface = user_input
            break
        else:
            print "Invalid interface name"
            continue

    while True:
        user_input = raw_input("Enter management address CIDR: ")
        try:
            management_cidr = netaddr.IPNetwork(user_input)
            management_ip = management_cidr.ip
            management_network = netaddr.IPNetwork(
                "%s/%s" % (str(management_cidr.network),
                           str(management_cidr.prefixlen)))
            if not is_valid_management_address(management_ip,
                                               management_network):
                continue
            break
        except (netaddr.AddrFormatError, ValueError):
            print ("Invalid CIDR - "
                   "please enter a valid management address CIDR")

    while True:
        user_input = raw_input("Enter management gateway address [" +
                               str(management_network[1]) + "]: ")
        if user_input == "":
            user_input = management_network[1]

        try:
            ip_input = netaddr.IPAddress(user_input)
            if not is_valid_management_address(ip_input,
                                               management_network):
                continue
            management_gateway_address = ip_input
            break
        except (netaddr.AddrFormatError, ValueError):
            print ("Invalid address - "
                   "please enter a valid management gateway address")

    min_addresses = 8
    while True:
        user_input = raw_input("Enter System Controller subnet: ")
        try:
            system_controller_subnet = cutils.validate_network_str(
                user_input, min_addresses)
            break
        except cexeptions.ValidateFail as e:
            print "{}".format(e)

    print "Disabling non-management interfaces... ",
    for interface in interface_list:
        if interface != management_interface:
            subprocess.call(['ip', 'link', 'set', interface, 'down'])
    print 'DONE'

    print "Configuring management interface... ",
    subprocess.call(['ip', 'addr', 'add', str(management_cidr), 'dev',
                     management_interface])
    print "DONE"

    print "Adding route to System Controller... ",
    subprocess.call(['ip', 'route', 'add', str(system_controller_subnet),
                     'dev', management_interface, 'via',
                     str(management_gateway_address)])
    print "DONE"


def main():
    if not os.geteuid() == 0:
        print "%s must be run with root privileges" % sys.argv[0]
        exit(1)
    try:
        configure_management()
    except KeyboardInterrupt:
        print "\nAborted"