#!/usr/bin/python
#
# Copyright 2014 Cumulus Networks, Inc. All rights reserved.
# Author: Roopa Prabhu, roopa@cumulusnetworks.com
#

from ifupdown.iface import *
from ifupdownaddons.modulebase import moduleBase
from ifupdownaddons.iproute2 import iproute2
from ifupdownaddons.bridgeutils import brctl
import logging

class bridgevlan(moduleBase):
    """  ifupdown2 addon module to configure vlan attributes on a vlan
         aware bridge """

    _modinfo = {'mhelp' : 'bridgevlan module configures vlan attributes ' +
                        'on a vlan aware bridge. This module only ' +
                        'understands vlan interface name ' +
                        'with dot notations. eg br0.100. where br0 is the ' +
                        'vlan aware bridge this config is for',
                'attrs' : {
                        'bridge-igmp-querier-src' :
                            {'help' : 'igmp querier src'}}}

    def __init__(self, *args, **kargs):
        moduleBase.__init__(self, *args, **kargs)
        self.brctlcmd = None
        self.ipcmd = None

    def _is_bridge_vlan_device(self, ifaceobj):
        if ifaceobj.type == ifaceType.BRIDGE_VLAN:
            return True
        return False

    def _get_bridge_n_vlan(self, ifaceobj):
        vlist = ifaceobj.name.split('.', 1)
        if len(vlist) == 2:
            return (vlist[0], vlist[1])
        return None

    def _get_bridgename(self, ifaceobj):
        vlist = ifaceobj.name.split('.', 1)
        if len(vlist) == 2:
            return vlist[0]
        return None

    def get_dependent_ifacenames(self, ifaceobj, ifaceobjs_all=None):
        if not self._is_bridge_vlan_device(ifaceobj):
            return None
        return [self._get_bridgename(ifaceobj)]

    def _up(self, ifaceobj):
        try:
            (bridgename, vlan) = self._get_bridge_n_vlan(ifaceobj)
            vlanid = int(vlan, 10)
        except:
            self.logger.warn('%s: bridge vlan interface name ' %ifaceobj.name +
                    'does not correspond to format (eg. br0.100)')
            raise

        if not self.ipcmd.link_exists(bridgename):
            self.logger.warn('%s: bridge %s does not exist' %(ifaceobj.name,
                             bridgename))
            return

        running_mcqv4src = {}
        if not self.PERFMODE:
            running_mcqv4src = self.brctlcmd.get_mcqv4src(bridgename)
        if running_mcqv4src:
            r_mcqv4src = running_mcqv4src.get(vlan)
        else:
            r_mcqv4src = None
        mcqv4src = ifaceobj.get_attr_value_first('bridge-igmp-querier-src')
        if not mcqv4src:
            if r_mcqv4src:
                self.brctlcmd.del_mcqv4src(bridgename, vlanid)
            return

        if r_mcqv4src and r_mcqv4src != mcqv4src:
            self.brctlcmd.del_mcqv4src(bridgename, vlanid)
            self.brctlcmd.set_mcqv4src(bridgename, vlanid, mcqv4src)
        else:
            self.brctlcmd.set_mcqv4src(bridgename, vlanid, mcqv4src)

    def _down(self, ifaceobj):
        try:
            (bridgename, vlan) = self._get_bridge_n_vlan(ifaceobj)
            vlanid = int(vlan, 10)
        except:
            self.logger.warn('%s: bridge vlan interface name ' %ifaceobj.name +
                    'does not correspond to format (eg. br0.100)')
            raise

        if not self.ipcmd.link_exists(bridgename):
            self.logger.warn('%s: bridge %s does not exist' %(ifaceobj.name,
                             bridgename))
            return

        mcqv4src = ifaceobj.get_attr_value_first('bridge-igmp-querier-src')
        if mcqv4src:
           self.brctlcmd.del_mcqv4src(bridgename, vlanid)

    def _query_check(self, ifaceobj, ifaceobjcurr):
        # XXX not supported
        return

    def _query_running(self, ifaceobjrunning):
        # XXX not supported
        return

    _run_ops = {'pre-up' : _up,
               'post-down' : _down,
               'query-checkcurr' : _query_check,
               'query-running' : _query_running}

    def get_ops(self):
        """ returns list of ops supported by this module """
        return self._run_ops.keys()

    def _init_command_handlers(self):
        if not self.ipcmd:
            self.ipcmd = iproute2(**self.get_flags())
        if not self.brctlcmd:
            self.brctlcmd = brctl(**self.get_flags())

    def run(self, ifaceobj, operation, query_ifaceobj=None, **extra_args):
        """ run vlan configuration on the interface object passed as argument

        Args:
            **ifaceobj** (object): iface object

            **operation** (str): any of 'pre-up', 'post-down', 'query-checkcurr',
                                 'query-running'
        Kwargs:
            **query_ifaceobj** (object): query check ifaceobject. This is only
                valid when op is 'query-checkcurr'. It is an object same as
                ifaceobj, but contains running attribute values and its config
                status. The modules can use it to return queried running state
                of interfaces. status is success if the running state is same
                as user required state in ifaceobj. error otherwise.
        """
        op_handler = self._run_ops.get(operation)
        if not op_handler:
            return
        if (operation != 'query-running' and
                not self._is_bridge_vlan_device(ifaceobj)):
            return
        self._init_command_handlers()
        if operation == 'query-checkcurr':
            op_handler(self, ifaceobj, query_ifaceobj)
        else:
            op_handler(self, ifaceobj)