#!/usr/bin/python
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
# 
#   http://www.apache.org/licenses/LICENSE-2.0
# 
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.
import sys
import re
from xml.dom.minidom import parse
from cloudutils.configFileOps import configFileOps
from cloudutils.networkConfig import networkConfig
def isOldStyleBridge(brName):
    if brName.find("cloudVirBr") == 0:
       return True
    else:
       return False
def isNewStyleBridge(brName):
    if re.match(r"br(\w+)-(\d+)", brName) == None:
       return False
    else:
       return True
def getGuestNetworkDevice():
    netlib = networkConfig() 
    cfo = configFileOps("/etc/cloudstack/agent/agent.properties")
    guestDev = cfo.getEntry("guest.network.device")
    enslavedDev = netlib.getEnslavedDev(guestDev, 1)
    return enslavedDev.split(".")[0]
def handleMigrateBegin():
    try:
        domain = parse(sys.stdin)
        for interface in domain.getElementsByTagName("interface"):
            source = interface.getElementsByTagName("source")[0]
            bridge = source.getAttribute("bridge")
            if isOldStyleBridge(bridge):
                vlanId = bridge.replace("cloudVirBr","")
            elif isNewStyleBridge(bridge):
                vlanId = re.sub(r"br(\w+)-","",bridge)
            else:
                continue
            phyDev = getGuestNetworkDevice()
            newBrName="br" + phyDev + "-" + vlanId
            source.setAttribute("bridge", newBrName)
        print(domain.toxml())
    except:
        pass
if __name__ == '__main__':
    if len(sys.argv) != 5:
        sys.exit(0)

    if sys.argv[2] == "migrate" and sys.argv[3] == "begin":
        handleMigrateBegin()