#!/usr/bin/env python
#
# Copyright (c) 2022 Pim van Pelt
#
# Licensed 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.
#
# -*- coding: utf-8 -*-
import logging
import config.loopback as loopback
import config.interface as interface
import config.bondethernet as bondethernet
import config.bridgedomain as bridgedomain
import config.vxlan_tunnel as vxlan_tunnel
import config.lcp as lcp
from vpp.vppapi import VPPApi

class Reconciler():
    def __init__(self, cfg):
        self.logger = logging.getLogger('vppcfg.vppapi')
        self.logger.addHandler(logging.NullHandler())

        self.vpp = VPPApi()
        self.cfg = cfg

    def readconfig(self):
        return self.vpp.readconfig()

    def phys_exist(self, ifname_list):
        """ Return True if all interfaces in the `ifname_list` exist as physical interface names
        in VPP. Return False otherwise."""
        ret = True
        for ifname in ifname_list:
            if not ifname in self.vpp.config['interface_names']:
                self.logger.warning("Interface %s does not exist in VPP" % ifname)
                ret = False
        return ret

    def prune_addresses(self, ifname, address_list):
        """ Remove all addresses from interface ifname, except those in address_list """
        idx = self.vpp.config['interface_names'][ifname].sw_if_index
        for a in self.vpp.config['interface_addresses'][idx]:
            self.logger.info("> set interface ip address del %s %s" % (ifname, a))
        
    def prune(self):
        ret = True
        if not self.prune_addresses_set_interface_down():
            self.logger.warning("Could not prune addresses and set interfaces down from VPP that are not in the config")
            ret = False
        if not self.prune_lcp():
            self.logger.warning("Could not prune LCPs from VPP that are not in the config")
            ret = False
        return ret

    def __parent_iface_by_encap(self, sup_sw_if_index, outer, dot1ad=True):
        """ Returns the idx of an interface on a given super_sw_if_index with given dot1q/dot1ad outer and inner-dot1q=0 """
        for idx, iface in self.vpp.config['interfaces'].items():
            if iface.sup_sw_if_index != sup_sw_if_index:
                continue
            if iface.sub_inner_vlan_id > 0:
                continue
            if dot1ad and (iface.sub_if_flags&8) and iface.sub_outer_vlan_id == outer:
                self.logger.debug("match: %s (dot1ad)" % iface.interface_name)
                return idx
            if not dot1ad and not (iface.sub_if_flags&8) and iface.sub_outer_vlan_id == outer:
                self.logger.debug("match: %s (dot1q)" % iface.interface_name)
                return idx
        return None

    def __get_encapsulation(self, iface):
        if iface.sub_if_flags&8:
            dot1ad = iface.sub_outer_vlan_id
            dot1q = 0
        else:
            dot1q = iface.sub_outer_vlan_id
            dot1ad = 0
        inner_dot1q = iface.sub_inner_vlan_id
        exact_match = iface.sub_if_flags&16
        return { "dot1q": int(dot1q),
                 "dot1ad": int(dot1ad),
                 "inner-dot1q": int(inner_dot1q),
                 "exact-match": bool(exact_match) }


    def prune_lcp(self):
        lcps = self.vpp.config['lcps']

        ## Remove LCPs for QinX interfaces
        for idx, lcp in lcps.items():
            vpp_iface = self.vpp.config['interfaces'][lcp.phy_sw_if_index]
            if vpp_iface.sub_inner_vlan_id == 0:
                continue
            config_ifname, config_iface = interface.get_by_lcp_name(self.cfg, lcp.host_if_name)
            if not config_iface:
                ## QinX doesn't exist in the config
                self.logger.info("1> lcp delete %s" % vpp_iface.interface_name)
                continue
            if not 'lcp' in config_iface:
                ## QinX doesn't have an LCP
                self.logger.info("2> lcp delete %s" % vpp_iface.interface_name)
                continue
            vpp_parent_idx = self.__parent_iface_by_encap(vpp_iface.sup_sw_if_index, vpp_iface.sub_outer_vlan_id, vpp_iface.sub_if_flags&8)
            vpp_parent_iface = self.vpp.config['interfaces'][vpp_parent_idx]
            parent_lcp = lcps[vpp_parent_iface.sw_if_index]
            config_parent_ifname, config_parent_iface = interface.get_by_lcp_name(self.cfg, parent_lcp.host_if_name)
            if not config_parent_iface:
                ## QinX's parent doesn't exist in the config
                self.logger.info("3> lcp delete %s" % vpp_iface.interface_name)
                continue
            if not 'lcp' in config_parent_iface:
                ## QinX's parent doesn't have an LCP
                self.logger.info("4> lcp delete %s" % vpp_iface.interface_name)
                continue
            if parent_lcp.host_if_name != config_parent_iface['lcp']:
                ## QinX's parent LCP name mismatch
                self.logger.info("5> lcp delete %s" % vpp_iface.interface_name)
                continue

            phy_lcp = lcps[vpp_iface.sup_sw_if_index]
            config_phy_ifname, config_phy_iface = interface.get_by_lcp_name(self.cfg, phy_lcp.host_if_name)
            if not config_phy_iface:
                ## QinX's phy doesn't exist in the config
                self.logger.info("6> lcp delete %s" % vpp_iface.interface_name)
                continue
            if not 'lcp' in config_phy_iface:
                ## QinX's phy doesn't have an LCP
                self.logger.info("6> lcp delete %s" % vpp_iface.interface_name)
                continue
            if phy_lcp.host_if_name != config_phy_iface['lcp']:
                ## QinX's phy LCP name mismatch
                self.logger.info("7> lcp delete %s" % vpp_iface.interface_name)
                continue

            config_encap = interface.get_encapsulation(self.cfg, config_ifname)
            vpp_encap = self.__get_encapsulation(vpp_iface)
            config_parent_encap = interface.get_encapsulation(self.cfg, config_parent_ifname)
            vpp_parent_encap = self.__get_encapsulation(vpp_parent_iface)
            if config_encap != vpp_encap:
                ## QinX's encapsulation mismatch
                self.logger.info("8> lcp delete %s" % vpp_iface.interface_name)
                continue
            if config_parent_encap != vpp_parent_encap:
                ## QinX's parent encapsulation mismatch
                self.logger.info("9> lcp delete %s" % vpp_iface.interface_name)
                continue
            self.logger.debug("QinX LCP OK: %s -> (vpp=%s, config=%s)" % (lcp.host_if_name, vpp_iface.interface_name, config_ifname))

        ## Remove LCPs for sub-interfaces
        for idx, lcp in lcps.items():
            vpp_iface = self.vpp.config['interfaces'][lcp.phy_sw_if_index]
            if vpp_iface.sub_inner_vlan_id > 0 or vpp_iface.sub_outer_vlan_id == 0:
                continue
            config_ifname, config_iface = interface.get_by_lcp_name(self.cfg, lcp.host_if_name)
            if not config_iface:
                ## Sub doesn't exist in the config
                self.logger.info("11> lcp delete %s" % vpp_iface.interface_name)
                continue
            if not 'lcp' in config_iface:
                ## Sub doesn't have an LCP
                self.logger.info("12> lcp delete %s" % vpp_iface.interface_name)
                continue

            phy_lcp = lcps[vpp_iface.sup_sw_if_index]
            config_phy_ifname, config_phy_iface = interface.get_by_lcp_name(self.cfg, phy_lcp.host_if_name)
            if not config_phy_iface:
                ## Sub's phy doesn't exist in the config
                self.logger.info("13> lcp delete %s" % vpp_iface.interface_name)
                continue
            if not 'lcp' in config_phy_iface:
                ## Sub's phy doesn't have an LCP
                self.logger.info("14> lcp delete %s" % vpp_iface.interface_name)
                continue
            if phy_lcp.host_if_name != config_phy_iface['lcp']:
                ## Sub's phy LCP name mismatch
                self.logger.info("15> lcp delete %s" % vpp_iface.interface_name)
                continue

            config_encap = interface.get_encapsulation(self.cfg, config_ifname)
            vpp_encap = self.__get_encapsulation(vpp_iface)
            if config_encap != vpp_encap:
                ## Sub's encapsulation mismatch
                self.logger.info("10> lcp delete %s" % vpp_iface.interface_name)
                continue
            self.logger.debug("Dot1Q/Dot1AD LCP OK: %s -> (vpp=%s, config=%s)" % (lcp.host_if_name, vpp_iface.interface_name, config_ifname))

        ## Remove LCPs for interfaces, bonds, tunnels, loops, bvis
        for idx, lcp in lcps.items():
            vpp_iface = self.vpp.config['interfaces'][lcp.phy_sw_if_index]
            if vpp_iface.sub_inner_vlan_id > 0 or vpp_iface.sub_outer_vlan_id > 0:
                continue

            if vpp_iface.interface_dev_type=='Loopback':
                config_ifname, config_iface = loopback.get_by_lcp_name(self.cfg, lcp.host_if_name)
            elif vpp_iface.interface_dev_type=='BVI':
                config_ifname, config_iface = bridgedomain.get_by_lcp_name(self.cfg, lcp.host_if_name)
            else:
                config_ifname, config_iface = interface.get_by_lcp_name(self.cfg, lcp.host_if_name)

            if not config_iface:
                ## Interface doesn't exist in the config
                self.logger.info("21> lcp delete %s" % vpp_iface.interface_name)
                continue
            if not 'lcp' in config_iface:
                ## Interface doesn't have an LCP
                self.logger.info("22> lcp delete %s" % vpp_iface.interface_name)
                continue
            self.logger.debug("LCP OK: %s -> (vpp=%s, config=%s)" % (lcp.host_if_name, vpp_iface.interface_name, config_ifname))

    def prune_addresses_set_interface_down(self):
        for ifname in self.vpp.get_qinx_interfaces() + self.vpp.get_dot1x_interfaces() + self.vpp.get_bondethernets() + self.vpp.get_vxlan_tunnels() + self.vpp.get_phys():
            if not ifname in interface.get_interfaces(self.cfg):
                self.logger.info("> set interface state %s down" % ifname)
                self.prune_addresses(ifname, [])

        return True

    def create(self):
        return False

    def sync(self):
        return False