from keystoneauth1 import identity
from keystoneauth1 import session
from neutronclient.v2_0 import client
from argparse import ArgumentParser
import os
import sys
import pdb
from ovs_vsctl import VSCtl
import subprocess
import ovs_vsctl.parser as ovs_vsctl_parser
"""
emit the commands you need to run to link a router namespace to a network.
To run this script create a port for the entwork you want to access.

Usage : python access-lbnet-from-qrouter.py port router

Leave out the router argument for the root namespace.
"""

vsctl = VSCtl('tcp', '127.0.0.1', 6640)

def find_internal_vlan_tag_for_network( network_id):
    interal_vlan_tag = -1
    ports = vsctl.run(command='list port',parser=ovs_vsctl_parser.list_cmd_parser)
    for port in ports:
        other_config = port.other_config
        if 'net_uuid' in other_config and str(other_config['net_uuid']) == network_id:
            internal_vlan_tag = other_config['tag']
            break
    return internal_vlan_tag


if __name__ == "__main__":
    parser = ArgumentParser()
    parser.add_argument("port", help = "network port", default = None)
    parser.add_argument("router", help = "Router name that you want to link to", default = None)

    args = parser.parse_args()
    router_name = args.router username= os.environ.get("OS_USERNAME")
    password= os.environ.get("OS_PASSWORD")
    project_name= os.environ.get("OS_PROJECT_NAME")
    project_domain_id='default'
    if os.environ.get("OS_PROJECT_DOMAIN_NAME") is not None:
       project_domain_id = os.environ.get("OS_PROJECT_DOMAIN_NAME")
    user_domain_id='default'
    if os.environ.get("OS_USER_DOMAIN_NAME") is not None:
        user_domain_id= os.environ.get("OS_USER_DOMAIN_NAME")
    auth_url= os.environ.get("OS_AUTH_URL")
    if auth_url is None:
       print "Missing auth url ... set OS_AUTH_URL environment variable"
       sys.exit()
    auth = identity.Password(auth_url=auth_url,
                    username=username,
                    password=password,
                    project_name=project_name,
                    project_domain_id=project_domain_id,
                    user_domain_id=user_domain_id)
    sess = session.Session(auth=auth)
    neutron = client.Client(session=sess)
    ports = neutron.list_ports()['ports']
    lb_ovs_port_name = None
    port_mac_address = None
    port_ip_address = None
    network_id = None
    for port in ports:
        if port_name == port['id'] or port_name == port['name']:
            if lb_ovs_port_name is None:
                lb_ovs_port_name = "lb-" + port['id'][0:11]
                port_mac_address = port['mac_address']
                port_ip_address = port['fixed_ips'][0]['ip_address']
                network_id = port['network_id']
            else:
                print ("ERROR: More than one port with name " + port_name)
                break


    if port_ip_address is None or network_id is None or port_mac_address is None:
        print("Cant find port assignments")
        sys.exit()


    ovs_command = "ovs-vsctl add-port br-int {} -- set interface {} type=internal -- set port {} tag={} -- set port {} other-config:hwaddr={}"\
                    .format(lb_ovs_port_name,lb_ovs_port_name,lb_ovs_port_name,vlan_tag,lb_ovs_port_name,port_mac_address)

    print ovs_command
    ifconfig_command = "ifconfig {} {}".format(lb_ovs_port_name,port_ip_address)
    if router_name is None:
       print ifconfig_command
    else:
       routers = neutron.list_routers()['routers']
       router_id = None
       for router in routers:
           if str(router['name']) == router_name:
               router_id = router['id']
           elif str(router['id']) == router_name:
               router_id = router_name

       if router_id is None:
            print ("Cannot find router " + router_name)
            sys.exit()
       router_namespace = "qrouter-" + router_id
       print "ip link set {} netns {}".format(lb_ovs_port_name,router_namespace)
       print "ip netns exec " + router_namespace + " " + ifconfig_command


    vlan_tag = find_internal_vlan_tag_for_network(network_id)

    port_name = args.port
    if port_name is None:
       print "Specify lbnet"
       sys.exit()
    username= os.environ.get("OS_USERNAME")
    password= os.environ.get("OS_PASSWORD")
    project_name= os.environ.get("OS_PROJECT_NAME")
    project_domain_id='default'
    if os.environ.get("OS_PROJECT_DOMAIN_NAME") is not None:
       project_domain_id = os.environ.get("OS_PROJECT_DOMAIN_NAME")
    user_domain_id='default'