#!/usr/bin/python
# Copyright 2016 Red Hat, Inc.
#
#    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.

import argparse
import logging
import os
import pwd
import shutil
import socket
import subprocess
import sys
import time
import copy
import tempfile
import getpass
from ipapython.ipautil import run, kinit_password, user_input
from ipalib import api
from ipalib import errors
from novajoin.errors import ConfigurationError
from novajoin import configure_ipa
from six.moves import input
from six.moves.configparser import ConfigParser
from subprocess import CalledProcessError
from string import Template


DATADIR = '/usr/share/novajoin'
NOVADIR = '/etc/nova'
IPACONF = '/etc/ipa/default.conf'
NOVACONF = '/etc/nova/nova.conf'
JOINCONF = '/etc/nova/join.conf'


LOGFILE = '/var/log/novajoin-install.log'
logger = logging.getLogger()


def openlogs():
    global logger  # pylint: disable=W0603
    if os.path.isfile(LOGFILE):
        try:
            created = '%s' % time.strftime(
                '%Y%m%d%H%M%SZ', time.gmtime(os.path.getctime(LOGFILE)))
            shutil.move(LOGFILE, '%s.%s' % (LOGFILE, created))
        except IOError:
            pass
    logger = logging.getLogger()
    try:
        lh = logging.FileHandler(LOGFILE)
    except IOError as e:
        print >> sys.stderr, 'Unable to open %s (%s)' % (LOGFILE, str(e))
        lh = logging.StreamHandler(sys.stderr)
    formatter = logging.Formatter('[%(asctime)s] %(message)s')
    lh.setFormatter(formatter)
    lh.setLevel(logging.DEBUG)
    logger.addHandler(lh)
    logger.propagate = False
    ch = logging.StreamHandler(sys.stdout)
    formatter = logging.Formatter('%(message)s')
    ch.setFormatter(formatter)
    ch.setLevel(logging.INFO)
    logger.addHandler(ch)


def write_from_template(destfile, template, opts):
    with open(template) as f:
        t = Template(f.read())
    text = t.substitute(**opts)
    with open(destfile, 'w+') as f:
        f.write(text)
    logger.debug(destfile)
    logger.debug(text)


def install(args):
    logger.info('Installation initiated')

    if not os.path.exists(IPACONF):
        raise ConfigurationError('Must be enrolled in IPA')

    try:
        os.environ['OS_PASSWORD']
        os.environ['OS_USERNAME']
        os.environ['OS_AUTH_URL']
    except KeyError as e:
        raise ConfigurationError('%s environment variable not set.'
                                 % e.message)

    try:
        user = pwd.getpwnam(args['user'])
    except KeyError:
        raise ConfigurationError('User: %s not found on the system' %
                                 args['user'])

    api.bootstrap(context='novajoin')
    api.finalize()

    novajoin = configure_ipa.NovajoinRole(user=args.get('user'))
    if not args.get('no_kinit', False):
        novajoin.kinit(args.get('principal'), args.get('password'))

    try:
        api.Backend.rpcclient.connect()
    except errors.CCacheError:
        raise ConfigurationError("No Kerberos credentials")

    logger.info('Installing default config files')

    confopts = {'FQDN': args['hostname'],
                'MASTER': api.env.server,  # pylint: disable=no-member
                'DOMAIN': api.env.domain,  # pylint: disable=no-member
                'KEYSTONE_AUTH_URL': args['keystone_auth_url'],
                'NOVA_PASSWORD': args['nova_password'],
                }

    write_from_template(JOINCONF,
                        os.path.join(DATADIR, 'join.conf.template'),
                        confopts)

    FILES = ['cloud-config.json']
    for fn in FILES:
        dst = os.path.join(NOVADIR, fn)
        source = os.path.join(DATADIR, fn)
        logger.info('Installing %s' % dst)
        shutil.copyfile(source, dst)

    config = ConfigParser()
    config.read(NOVACONF)
    config.set('DEFAULT',
               'vendordata_jsonfile_path',
               '/etc/nova/cloud-config.json')

    # set the default domain to the IPA domain. This is added to the
    # instance name to set the hostname.
    config.set('DEFAULT',
               'dhcp_domain',
               api.env.domain)

    # Novajoin service
    config.set('DEFAULT',
               'vendordata_providers',
               'StaticJSON, DynamicJSON')

    config.set('DEFAULT',
               'vendordata_dynamic_targets',
               'join@http://127.0.0.1:9999/v1/')

    # Notifications
    config.set('DEFAULT',
               'notification_topic',
               'notifications')

    config.set('DEFAULT',
               'notify_on_state_change',
               'vm_state')

    try:
        transport_url = config.get('DEFAULT', 'transport_url')
    except ConfigParser.NoOptionError:
        transport_url = None

    with open(NOVACONF, 'w') as f:
        config.write(f)

    if transport_url:
        join_config = ConfigParser()
        join_config.read(JOINCONF)
        join_config.set('DEFAULT', 'transport_url', transport_url)
        with open(JOINCONF, 'w') as f:
            join_config.write(f)

    logger.info('Importing IPA metadata')
    (stdout, stderr, returncode) = run(
        ['glance',
         '--os-image-api-version',
         '2',
         'md-namespace-import',
         '--file',
         '/usr/share/novajoin/freeipa.json'], raiseonerr=False)
    if returncode != 0:
        logger.error('Adding IPA metadata failed: %s' % stderr)

    logger.info('Creating IPA permissions')

    novajoin.configure_ipa()


def parse_args():
    parser = argparse.ArgumentParser(description='Nova join Install Options')
    parser.add_argument('--hostname',
                        help='Machine\'s fully qualified host name')
    parser.add_argument('--keystone-auth-url', dest='keystone_auth_url',
                        help='Keystone auth URL')
    parser.add_argument('--nova-password', dest='nova_password',
                        help='Nova service user password')
    parser = configure_ipa.ipa_options(parser)

    args = vars(parser.parse_args())

    configure_ipa.validate_options(args)

    if not args['hostname']:
        args['hostname'] = socket.getfqdn()

    if len(args['hostname'].split('.')) < 2:
        raise ConfigurationError('Hostname: %s is not a FQDN' %
                                 args['hostname'])

    if not args['keystone_auth_url']:
        args['keystone_auth_url'] = user_input("Keystone auth URL", "",
                                               allow_empty=False)

    if not args['nova_password']:
        try:
            args['nova_password'] = getpass.getpass("nova service Password: ")
        except EOFError:
            args['nova_password'] = None
        if not args['nova_password']:
            raise ConfigurationError('nova service user password required.')

    try:
        pwd.getpwnam(args['user'])
    except KeyError:
        raise ConfigurationError('User: %s not found on the system' %
                                 args['user'])

    return args

if __name__ == '__main__':
    opts = []
    out = 0
    openlogs()
    logger.setLevel(logging.DEBUG)

    try:
        opts = parse_args()

        logger.debug('Installation arguments:')
        for k in sorted(opts.iterkeys()):
            logger.debug('%s: %s', k, opts[k])

        install(opts)
    except Exception as e:  # pylint: disable=broad-except
        logger.info(str(e))          # emit message to console
        logger.debug(e, exc_info=1)  # add backtrace information to logfile

        logger.info('Installation aborted.')
        logger.info('See log file %s for details' % LOGFILE)
        out = 1
    except SystemExit:
        out = 1
        raise
    finally:
        if out == 0:
            logger.info('Installation complete.')
            logger.info(
                'Please restart nova-api to enable the join service.')
    sys.exit(out)
