# -*- Mode:python; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
#
# Copyright (C) 2015-2021, The University of Memphis,
#                          Arizona Board of Regents,
#                          Regents of the University of California.
#
# This file is part of Mini-NDN.
# See AUTHORS.md for a complete list of Mini-NDN authors and contributors.
#
# Mini-NDN is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Mini-NDN is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Mini-NDN, e.g., in COPYING.md file.
# If not, see <http://www.gnu.org/licenses/>.

import shutil
import os, sys

from mininet.clean import sh
from mininet.examples.cluster import RemoteMixin
from mininet.log import warn
from mininet.node import Switch

from minindn.apps.application import Application
from minindn.util import scp, copyExistentFile
from minindn.helpers.nfdc import Nfdc
from minindn.minindn import Minindn

class Nlsr(Application):
    ROUTING_LINK_STATE = 'link-state'
    ROUTING_HYPERBOLIC = 'hr'
    ROUTING_DRY_RUN = 'dry'
    SYNC_PSYNC = 'psync'

    def __init__(self, node, logLevel='NONE', security=False, sync=SYNC_PSYNC,
                 faceType='udp', nFaces=3, routingType=ROUTING_LINK_STATE):
        Application.__init__(self, node)

        self.network = '/ndn/'
        self.node = node
        self.parameters = self.node.params['params']

        if self.parameters.get('nlsr-log-level', None) != None:
            logLevel = self.parameters.get('nlsr-log-level')

        if logLevel in ['NONE', 'WARN', 'INFO', 'DEBUG', 'TRACE']:
            self.envDict = {'NDN_LOG': 'nlsr.*={}'.format(logLevel)}
        else:
            self.envDict = {'NDN_LOG': logLevel}

        self.logFile = 'nlsr.log'
        self.routerName = '/{}C1.Router/cs/{}'.format('%', node.name)
        self.confFile = '{}/nlsr.conf'.format(self.homeDir)
        self.security = security
        self.sync = sync
        self.faceType = faceType
        self.infocmd = 'infoedit -f nlsr.conf'

        self.parameters = self.node.params['params']

        self.nFaces = nFaces
        if routingType == Nlsr.ROUTING_HYPERBOLIC:
            self.hyperbolicState = 'on'
        elif routingType == Nlsr.ROUTING_DRY_RUN:
            self.hyperbolicState = 'dry-run'
        else:
            self.hyperbolicState = 'off'
        self.hyperRadius = self.parameters.get('radius', 0.0)
        self.hyperAngle = self.parameters.get('angle', 0.0)

        if ((self.hyperbolicState == 'on' or self.hyperbolicState == 'dry-run') and
            (self.hyperRadius == 0.0 or self.hyperAngle == 0.0)):
            warn('Hyperbolic coordinates in topology file are either missing or misconfigured.')
            warn('Check that each node has one radius value and one or two angle value(s).')
            sys.exit(1)

        self.neighborIPs = []
        possibleConfPaths = ['/usr/local/etc/ndn/nlsr.conf.sample', '/etc/ndn/nlsr.conf.sample']
        copyExistentFile(node, possibleConfPaths, '{}/nlsr.conf'.format(self.homeDir))

        self.createConfigFile()

        if security and not Minindn.ndnSecurityDisabled:
            self.createKeysAndCertificates()

    def start(self):
        self.createFaces()
        Application.start(self, 'nlsr -f {}'.format(self.confFile), self.logFile, self.envDict)
        Minindn.sleep(1)

    def createFaces(self):
        for ip in self.neighborIPs:
            Nfdc.createFace(self.node, ip, self.faceType, isPermanent=True)

    @staticmethod
    def createKey(host, name, outputFile):
        host.cmd('ndnsec-keygen {} > {}'.format(name, outputFile))

    @staticmethod
    def createCertificate(host, signer, keyFile, outputFile):
        host.cmd('ndnsec-certgen -s {} -r {} > {}'.format(signer, keyFile, outputFile))

    def createKeysAndCertificates(self):
        securityDir = '{}/security'.format(Minindn.workDir)

        if not os.path.exists(securityDir):
            os.mkdir(securityDir)

        rootName = self.network
        rootCertFile = '{}/root.cert'.format(securityDir)
        if not os.path.isfile(rootCertFile):
            # Create root certificate
            sh('ndnsec-keygen {}'.format(rootName)) # Installs a self-signed cert into the system
            sh('ndnsec-cert-dump -i {} > {}'.format(rootName, rootCertFile))

        # Create necessary certificates for each site
        nodeSecurityFolder = '{}/security'.format(self.homeDir)

        self.node.cmd('mkdir -p {}'.format(nodeSecurityFolder))

        # Create temp folders for remote nodes on this machine (localhost) to store site.key file
        # from RemoteNodes
        if not os.path.exists(nodeSecurityFolder) and \
            isinstance(self.node, RemoteMixin) and self.node.isRemote:
            os.makedirs(nodeSecurityFolder)

        shutil.copyfile('{}/root.cert'.format(securityDir),
                        '{}/root.cert'.format(nodeSecurityFolder))

        # Create site certificate
        siteName = '{}{}-site'.format(self.network, self.node.name)
        siteKeyFile = '{}/site.keys'.format(nodeSecurityFolder)
        siteCertFile = '{}/site.cert'.format(nodeSecurityFolder)
        Nlsr.createKey(self.node, siteName, siteKeyFile)

        # Copy siteKeyFile from remote for ndnsec-certgen
        if isinstance(self.node, RemoteMixin) and self.node.isRemote:
            login = 'mininet@{}'.format(self.node.server)
            src = '{}:{}'.format(login, siteKeyFile)
            dst = siteKeyFile
            scp(src, dst)

        # Root key is in root namespace, must sign site key and then install on host
        sh('ndnsec-certgen -s {} -r {} > {}'.format(rootName, siteKeyFile, siteCertFile))

        # Copy root.cert and site.cert from localhost to remote host
        if isinstance(self.node, RemoteMixin) and self.node.isRemote:
            login = 'mininet@{}'.format(self.node.server)
            src = '{}/site.cert'.format(nodeSecurityFolder)
            src2 = '{}/root.cert'.format(nodeSecurityFolder)
            dst = '{}:/tmp/'.format(login)
            scp(src, src2, dst)
            self.node.cmd('mv /tmp/*.cert {}'.format(nodeSecurityFolder))

        self.node.cmd('ndnsec-cert-install -f {}'.format(siteCertFile))

        # Create and install operator certificate
        opName = '{}/%C1.Operator/op'.format(siteName)
        opKeyFile = '{}/op.keys'.format(nodeSecurityFolder)
        opCertFile = '{}/op.cert'.format(nodeSecurityFolder)
        Nlsr.createKey(self.node, opName, opKeyFile)
        Nlsr.createCertificate(self.node, siteName, opKeyFile, opCertFile)
        self.node.cmd('ndnsec-cert-install -f {}'.format(opCertFile))

        # Create and install router certificate
        routerName = '{}/%C1.Router/cs/{}'.format(siteName, self.node.name)
        routerKeyFile = '{}/router.keys'.format(nodeSecurityFolder)
        routerCertFile = '{}/router.cert'.format(nodeSecurityFolder)
        Nlsr.createKey(self.node, routerName, routerKeyFile)
        Nlsr.createCertificate(self.node, opName, routerKeyFile, routerCertFile)
        self.node.cmd('ndnsec-cert-install -f {}'.format(routerCertFile))

    def createConfigFile(self):

        self.__editGeneralSection()
        self.__editNeighborsSection()
        self.__editHyperbolicSection()
        self.__editFibSection()
        self.__editAdvertisingSection()
        self.__editSecuritySection()

    def __editGeneralSection(self):

        self.node.cmd('{} -s general.network -v {}'.format(self.infocmd, self.network))
        self.node.cmd('{} -s general.site -v /{}-site'.format(self.infocmd, self.node.name))
        self.node.cmd('{} -s general.router -v /%C1.Router/cs/{}'.format(self.infocmd, self.node.name))
        self.node.cmd('{} -s general.state-dir -v {}/log'.format(self.infocmd, self.homeDir))
        self.node.cmd('{} -s general.sync-protocol -v {}'.format(self.infocmd, self.sync))

    def __editNeighborsSection(self):

        self.node.cmd('{} -d neighbors.neighbor'.format(self.infocmd))
        for intf in self.node.intfList():
            link = intf.link
            if not link:
                continue

            node1, node2 = link.intf1.node, link.intf2.node

            # Todo: add some switch support
            if isinstance(node1, Switch) or isinstance(node2, Switch):
                continue

            if node1 == self.node:
                other = node2
                ip = other.IP(str(link.intf2))
            else:
                other = node1
                ip = other.IP(str(link.intf1))

            linkCost = intf.params.get('delay', '10ms').replace('ms', '')

            self.neighborIPs.append(ip)

            self.node.cmd('{} -a neighbors.neighbor \
                          <<<\'name {}{}-site/%C1.Router/cs/{} face-uri {}://{}\n link-cost {}\''
                          .format(self.infocmd, self.network, other.name, other.name,
                                  self.faceType, ip, linkCost))

    def __editHyperbolicSection(self):

        self.node.cmd('{} -s hyperbolic.state -v {}'.format(self.infocmd, self.hyperbolicState))
        self.node.cmd('{} -s hyperbolic.radius -v {}'.format(self.infocmd, self.hyperRadius))
        self.node.cmd('{} -s hyperbolic.angle -v {}'.format(self.infocmd, self.hyperAngle))

    def __editFibSection(self):

        self.node.cmd('{} -s fib.max-faces-per-prefix  -v {}'.format(self.infocmd, self.nFaces))

    def __editAdvertisingSection(self):

        self.node.cmd('{} -d advertising.prefix'.format(self.infocmd))
        self.node.cmd('{} -s advertising.prefix -v {}{}-site/{}'
                      .format(self.infocmd, self.network, self.node.name, self.node.name))

    def __editSecuritySection(self):

        self.node.cmd('{} -d security.cert-to-publish'.format(self.infocmd))
        if not self.security:
            self.node.cmd('{} -s security.validator.trust-anchor.type -v any'.format(self.infocmd))
            self.node.cmd('{} -d security.validator.trust-anchor.file-name'.format(self.infocmd))
            self.node.cmd('{} -s security.prefix-update-validator.trust-anchor.type -v any'.format(self.infocmd))
            self.node.cmd('{} -d security.prefix-update-validator.trust-anchor.file-name'.format(self.infocmd))
        else:
            self.node.cmd('{} -s security.validator.trust-anchor.file-name -v security/root.cert'.format(self.infocmd))
            self.node.cmd('{} -s security.prefix-update-validator.trust-anchor.file-name -v security/site.cert'.format(self.infocmd))
            self.node.cmd('{} -p security.cert-to-publish -v security/site.cert'.format(self.infocmd))
            self.node.cmd('{} -p security.cert-to-publish -v security/op.cert'.format(self.infocmd))
            self.node.cmd('{} -p security.cert-to-publish -v security/router.cert'.format(self.infocmd))