#!/usr/bin/python

import sys
import uuid
from subprocess import (
    check_call,
)

from charmhelpers.core.hookenv import (
    Hooks,
    UnregisteredHookError,
    config,
    is_relation_made,
    local_unit,
    log,
    ERROR,
    relation_get,
    relation_ids,
    relation_set,
    status_set,
    open_port,
    unit_get,
    network_get_primary_address,
)

from charmhelpers.core.host import (
    mkdir,
    service_reload,
    service_restart,
)

from charmhelpers.fetch import (
    apt_install,
    add_source,
    apt_update,
    filter_installed_packages,
)

from charmhelpers.contrib.openstack.utils import (
    config_value_changed,
    configure_installation_source,
    set_os_workload_status,
    git_install_requested,
    openstack_upgrade_available,
    os_requires_version,
    os_release,
    sync_db_with_multi_ipv6_addresses,
    is_unit_paused_set,
    pausable_restart_on_change as restart_on_change,
)

from neutron_api_utils import (
    CLUSTER_RES,
    NEUTRON_CONF,
    REQUIRED_INTERFACES,
    api_port,
    determine_packages,
    determine_ports,
    do_openstack_upgrade,
    git_install,
    is_api_ready,
    dvr_router_present,
    l3ha_router_present,
    migrate_neutron_database,
    neutron_ready,
    register_configs,
    restart_map,
    services,
    setup_ipv6,
    get_topics,
    check_optional_relations,
    additional_install_locations,
    force_etcd_restart,
)
from neutron_api_context import (
    get_dvr,
    get_l3ha,
    get_l2population,
    get_overlay_network_type,
    IdentityServiceContext,
    EtcdContext,
)

from charmhelpers.contrib.hahelpers.cluster import (
    get_hacluster_config,
    is_elected_leader,
)

from charmhelpers.payload.execd import execd_preinstall

from charmhelpers.contrib.openstack.ip import (
    canonical_url,
    PUBLIC, INTERNAL, ADMIN
)

from charmhelpers.contrib.openstack.neutron import (
    neutron_plugin_attribute,
)

from charmhelpers.contrib.network.ip import (
    get_iface_for_address,
    get_netmask_for_address,
    get_address_in_network,
    get_ipv6_addr,
    is_ipv6
)

from charmhelpers.contrib.openstack.context import ADDRESS_TYPES

from charmhelpers.contrib.charmsupport import nrpe
from charmhelpers.contrib.hardening.harden import harden

hooks = Hooks()
CONFIGS = register_configs()


def conditional_neutron_migration():
    if os_release('neutron-server') <= 'icehouse':
        log('Not running neutron database migration as migrations are handled '
            'by the neutron-server process.')
        return
    if is_elected_leader(CLUSTER_RES):
        allowed_units = relation_get('allowed_units')
        if allowed_units and local_unit() in allowed_units.split():
            migrate_neutron_database()
            if not is_unit_paused_set():
                service_restart('neutron-server')
        else:
            log('Not running neutron database migration, either no'
                ' allowed_units or this unit is not present')
            return
    else:
        log('Not running neutron database migration, not leader')


def configure_https():
    '''
    Enables SSL API Apache config if appropriate and kicks identity-service
    with any required api updates.
    '''
    # need to write all to ensure changes to the entire request pipeline
    # propagate (c-api, haprxy, apache)
    CONFIGS.write_all()
    if 'https' in CONFIGS.complete_contexts():
        cmd = ['a2ensite', 'openstack_https_frontend']
        check_call(cmd)
    else:
        cmd = ['a2dissite', 'openstack_https_frontend']
        check_call(cmd)

    # TODO: improve this by checking if local CN certs are available
    # first then checking reload status (see LP #1433114).
    if not is_unit_paused_set():
        service_reload('apache2', restart_on_failure=True)

    for rid in relation_ids('identity-service'):
        identity_joined(rid=rid)


@hooks.hook('install.real')
@hooks.hook()
@harden()
def install():
    status_set('maintenance', 'Executing pre-install')
    execd_preinstall()
    openstack_origin = config('openstack-origin')
    configure_installation_source(openstack_origin)
    neutron_plugin = config('neutron-plugin')
    additional_install_locations(neutron_plugin, openstack_origin)

    add_source(config('extra-source'), config('extra-key'))
    status_set('maintenance', 'Installing apt packages')
    apt_update(fatal=True)
    packages = determine_packages(openstack_origin)
    apt_install(packages, fatal=True)

    status_set('maintenance', 'Git install')
    git_install(config('openstack-origin-git'))

    [open_port(port) for port in determine_ports()]

    if neutron_plugin == 'midonet':
        mkdir('/etc/neutron/plugins/midonet', owner='neutron', group='neutron',
              perms=0o755, force=False)


@hooks.hook('vsd-rest-api-relation-joined')
@restart_on_change(restart_map(), stopstart=True)
def relation_set_nuage_cms_name(rid=None):
    if os_release('neutron-server') >= 'kilo':
        if config('vsd-cms-name') is None:
            e = "Neutron Api hook failed as vsd-cms-name" \
                " is not specified"
            status_set('blocked', e)
        else:
            relation_data = {
                'vsd-cms-name': '{}'.format(config('vsd-cms-name'))
            }
            relation_set(relation_id=rid, **relation_data)


@hooks.hook('vsd-rest-api-relation-changed')
@restart_on_change(restart_map(), stopstart=True)
def vsd_changed(relation_id=None, remote_unit=None):
    if config('neutron-plugin') == 'vsp':
        vsd_ip_address = relation_get('vsd-ip-address')
        if not vsd_ip_address:
            return
        vsd_address = '{}:8443'.format(vsd_ip_address)
        if os_release('neutron-server') >= 'kilo':
            vsd_cms_id = relation_get('nuage-cms-id')
            log("nuage-vsd-api-relation-changed : cms_id:{}"
                .format(vsd_cms_id))
        nuage_config_file = neutron_plugin_attribute(config('neutron-plugin'),
                                                     'config', 'neutron')
        log('vsd-rest-api-relation-changed: ip address:{}'.format(vsd_address))
        log('vsd-rest-api-relation-changed:{}'.format(nuage_config_file))

        CONFIGS.write(nuage_config_file)


@hooks.hook('upgrade-charm')
@hooks.hook('config-changed')
@restart_on_change(restart_map(), stopstart=True)
@harden()
def config_changed():
    # If neutron is ready to be queried then check for incompatability between
    # existing neutron objects and charm settings
    if neutron_ready():
        if l3ha_router_present() and not get_l3ha():
            e = ('Cannot disable Router HA while ha enabled routers exist.'
                 ' Please remove any ha routers')
            status_set('blocked', e)
            raise Exception(e)
        if dvr_router_present() and not get_dvr():
            e = ('Cannot disable dvr while dvr enabled routers exist. Please'
                 ' remove any distributed routers')
            log(e, level=ERROR)
            status_set('blocked', e)
            raise Exception(e)
    if config('prefer-ipv6'):
        status_set('maintenance', 'configuring ipv6')
        setup_ipv6()
        sync_db_with_multi_ipv6_addresses(config('database'),
                                          config('database-user'))

    global CONFIGS
    if git_install_requested():
        if config_value_changed('openstack-origin-git'):
            status_set('maintenance', 'Running Git install')
            git_install(config('openstack-origin-git'))
    elif not config('action-managed-upgrade'):
        if openstack_upgrade_available('neutron-common'):
            status_set('maintenance', 'Running openstack upgrade')
            do_openstack_upgrade(CONFIGS)

    additional_install_locations(
        config('neutron-plugin'),
        config('openstack-origin')
    )
    status_set('maintenance', 'Installing apt packages')
    apt_install(filter_installed_packages(
                determine_packages(config('openstack-origin'))),
                fatal=True)
    configure_https()
    update_nrpe_config()
    CONFIGS.write_all()
    for r_id in relation_ids('neutron-api'):
        neutron_api_relation_joined(rid=r_id)
    for r_id in relation_ids('neutron-plugin-api'):
        neutron_plugin_api_relation_joined(rid=r_id)
    for r_id in relation_ids('amqp'):
        amqp_joined(relation_id=r_id)
    for r_id in relation_ids('identity-service'):
        identity_joined(rid=r_id)
    for rid in relation_ids('zeromq-configuration'):
        zeromq_configuration_relation_joined(rid)
    [cluster_joined(rid) for rid in relation_ids('cluster')]


@hooks.hook('amqp-relation-joined')
def amqp_joined(relation_id=None):
    relation_set(relation_id=relation_id,
                 username=config('rabbit-user'), vhost=config('rabbit-vhost'))


@hooks.hook('amqp-relation-changed')
@hooks.hook('amqp-relation-departed')
@restart_on_change(restart_map())
def amqp_changed():
    if 'amqp' not in CONFIGS.complete_contexts():
        log('amqp relation incomplete. Peer not ready?')
        return
    CONFIGS.write(NEUTRON_CONF)

    for r_id in relation_ids('neutron-plugin-api-subordinate'):
        neutron_plugin_api_subordinate_relation_joined(relid=r_id)


@hooks.hook('shared-db-relation-joined')
def db_joined():
    if is_relation_made('pgsql-db'):
        # error, postgresql is used
        e = ('Attempting to associate a mysql database when there is already '
             'associated a postgresql one')
        log(e, level=ERROR)
        raise Exception(e)

    if config('prefer-ipv6'):
        sync_db_with_multi_ipv6_addresses(config('database'),
                                          config('database-user'))
    else:
        host = None
        try:
            # NOTE: try to use network spaces
            host = network_get_primary_address('shared-db')
        except NotImplementedError:
            # NOTE: fallback to private-address
            host = unit_get('private-address')

        relation_set(database=config('database'),
                     username=config('database-user'),
                     hostname=host)


@hooks.hook('pgsql-db-relation-joined')
def pgsql_neutron_db_joined():
    if is_relation_made('shared-db'):
        # raise error
        e = ('Attempting to associate a postgresql database'
             ' when there is already associated a mysql one')
        log(e, level=ERROR)
        raise Exception(e)

    relation_set(database=config('database'))


@hooks.hook('shared-db-relation-changed')
@restart_on_change(restart_map())
def db_changed():
    if 'shared-db' not in CONFIGS.complete_contexts():
        log('shared-db relation incomplete. Peer not ready?')
        return
    CONFIGS.write_all()
    conditional_neutron_migration()

    for r_id in relation_ids('neutron-plugin-api-subordinate'):
        neutron_plugin_api_subordinate_relation_joined(relid=r_id)


@hooks.hook('pgsql-db-relation-changed')
@restart_on_change(restart_map())
def postgresql_neutron_db_changed():
    CONFIGS.write(NEUTRON_CONF)
    conditional_neutron_migration()

    for r_id in relation_ids('neutron-plugin-api-subordinate'):
        neutron_plugin_api_subordinate_relation_joined(relid=r_id)


@hooks.hook('amqp-relation-broken',
            'identity-service-relation-broken',
            'shared-db-relation-broken',
            'pgsql-db-relation-broken')
def relation_broken():
    CONFIGS.write_all()


@hooks.hook('identity-service-relation-joined')
def identity_joined(rid=None, relation_trigger=False):
    public_url = '{}:{}'.format(canonical_url(CONFIGS, PUBLIC),
                                api_port('neutron-server'))
    admin_url = '{}:{}'.format(canonical_url(CONFIGS, ADMIN),
                               api_port('neutron-server'))
    internal_url = '{}:{}'.format(canonical_url(CONFIGS, INTERNAL),
                                  api_port('neutron-server')
                                  )
    rel_settings = {
        'neutron_service': 'neutron',
        'neutron_region': config('region'),
        'neutron_public_url': public_url,
        'neutron_admin_url': admin_url,
        'neutron_internal_url': internal_url,
        'quantum_service': None,
        'quantum_region': None,
        'quantum_public_url': None,
        'quantum_admin_url': None,
        'quantum_internal_url': None,
    }
    if relation_trigger:
        rel_settings['relation_trigger'] = str(uuid.uuid4())
    relation_set(relation_id=rid, relation_settings=rel_settings)


@hooks.hook('identity-service-relation-changed')
@restart_on_change(restart_map())
def identity_changed():
    if 'identity-service' not in CONFIGS.complete_contexts():
        log('identity-service relation incomplete. Peer not ready?')
        return
    CONFIGS.write(NEUTRON_CONF)
    for r_id in relation_ids('neutron-api'):
        neutron_api_relation_joined(rid=r_id)
    for r_id in relation_ids('neutron-plugin-api'):
        neutron_plugin_api_relation_joined(rid=r_id)
    for r_id in relation_ids('neutron-plugin-api-subordinate'):
        neutron_plugin_api_subordinate_relation_joined(relid=r_id)
    configure_https()


@hooks.hook('neutron-api-relation-joined')
def neutron_api_relation_joined(rid=None):
    base_url = canonical_url(CONFIGS, INTERNAL)
    neutron_url = '%s:%s' % (base_url, api_port('neutron-server'))
    relation_data = {
        'neutron-url': neutron_url,
        'neutron-plugin': config('neutron-plugin'),
    }
    if config('neutron-security-groups'):
        relation_data['neutron-security-groups'] = "yes"
    else:
        relation_data['neutron-security-groups'] = "no"

    if is_api_ready(CONFIGS):
        relation_data['neutron-api-ready'] = "yes"
    else:
        relation_data['neutron-api-ready'] = "no"

    relation_set(relation_id=rid, **relation_data)
    # Nova-cc may have grabbed the neutron endpoint so kick identity-service
    # relation to register that its here
    for r_id in relation_ids('identity-service'):
        identity_joined(rid=r_id, relation_trigger=True)


@hooks.hook('neutron-api-relation-changed')
@restart_on_change(restart_map())
def neutron_api_relation_changed():
    CONFIGS.write(NEUTRON_CONF)


@hooks.hook('neutron-plugin-api-relation-joined')
def neutron_plugin_api_relation_joined(rid=None):
    if config('neutron-plugin') == 'nsx':
        relation_data = {
            'nsx-username': config('nsx-username'),
            'nsx-password': config('nsx-password'),
            'nsx-cluster-name': config('nsx-cluster-name'),
            'nsx-tz-uuid': config('nsx-tz-uuid'),
            'nsx-l3-uuid': config('nsx-l3-uuid'),
            'nsx-controllers': config('nsx-controllers'),
        }
    else:
        relation_data = {
            'neutron-security-groups': config('neutron-security-groups'),
            'l2-population': get_l2population(),
            'enable-dvr': get_dvr(),
            'enable-l3ha': get_l3ha(),
            'overlay-network-type': get_overlay_network_type(),
            'addr': unit_get('private-address'),
        }

        # Provide this value to relations since it needs to be set in multiple
        # places e.g. neutron.conf, nova.conf
        net_dev_mtu = config('network-device-mtu')
        if net_dev_mtu:
            relation_data['network-device-mtu'] = net_dev_mtu

    identity_ctxt = IdentityServiceContext()()
    if not identity_ctxt:
        identity_ctxt = {}

    relation_data.update({
        'auth_host': identity_ctxt.get('auth_host'),
        'auth_port': identity_ctxt.get('auth_port'),
        'auth_protocol': identity_ctxt.get('auth_protocol'),
        'service_protocol': identity_ctxt.get('service_protocol'),
        'service_host': identity_ctxt.get('service_host'),
        'service_port': identity_ctxt.get('service_port'),
        'service_tenant': identity_ctxt.get('admin_tenant_name'),
        'service_username': identity_ctxt.get('admin_user'),
        'service_password': identity_ctxt.get('admin_password'),
        'region': config('region'),
    })

    if is_api_ready(CONFIGS):
        relation_data['neutron-api-ready'] = "yes"
    else:
        relation_data['neutron-api-ready'] = "no"

    relation_set(relation_id=rid, **relation_data)


@hooks.hook('cluster-relation-joined')
def cluster_joined(relation_id=None):
    for addr_type in ADDRESS_TYPES:
        address = get_address_in_network(
            config('os-{}-network'.format(addr_type))
        )
        if address:
            relation_set(
                relation_id=relation_id,
                relation_settings={'{}-address'.format(addr_type): address}
            )
    if config('prefer-ipv6'):
        private_addr = get_ipv6_addr(exc_list=[config('vip')])[0]
        relation_set(relation_id=relation_id,
                     relation_settings={'private-address': private_addr})


@hooks.hook('cluster-relation-changed',
            'cluster-relation-departed')
@restart_on_change(restart_map(), stopstart=True)
def cluster_changed():
    CONFIGS.write_all()


@hooks.hook('ha-relation-joined')
def ha_joined():
    cluster_config = get_hacluster_config()
    resources = {
        'res_neutron_haproxy': 'lsb:haproxy',
    }
    resource_params = {
        'res_neutron_haproxy': 'op monitor interval="5s"'
    }
    vip_group = []
    for vip in cluster_config['vip'].split():
        if is_ipv6(vip):
            res_neutron_vip = 'ocf:heartbeat:IPv6addr'
            vip_params = 'ipv6addr'
        else:
            res_neutron_vip = 'ocf:heartbeat:IPaddr2'
            vip_params = 'ip'

        iface = (get_iface_for_address(vip) or
                 config('vip_iface'))
        netmask = (get_netmask_for_address(vip) or
                   config('vip_cidr'))

        if iface is not None:
            vip_key = 'res_neutron_{}_vip'.format(iface)
            resources[vip_key] = res_neutron_vip
            resource_params[vip_key] = (
                'params {ip}="{vip}" cidr_netmask="{netmask}" '
                'nic="{iface}"'.format(ip=vip_params,
                                       vip=vip,
                                       iface=iface,
                                       netmask=netmask)
            )
            vip_group.append(vip_key)

    if len(vip_group) >= 1:
        relation_set(groups={'grp_neutron_vips': ' '.join(vip_group)})

    init_services = {
        'res_neutron_haproxy': 'haproxy'
    }
    clones = {
        'cl_nova_haproxy': 'res_neutron_haproxy'
    }
    relation_set(init_services=init_services,
                 corosync_bindiface=cluster_config['ha-bindiface'],
                 corosync_mcastport=cluster_config['ha-mcastport'],
                 resources=resources,
                 resource_params=resource_params,
                 clones=clones)


@hooks.hook('ha-relation-changed')
def ha_changed():
    clustered = relation_get('clustered')
    if not clustered or clustered in [None, 'None', '']:
        log('ha_changed: hacluster subordinate'
            ' not fully clustered: %s' % clustered)
        return
    log('Cluster configured, notifying other services and updating '
        'keystone endpoint configuration')
    for rid in relation_ids('identity-service'):
        identity_joined(rid=rid)
    for rid in relation_ids('neutron-api'):
        neutron_api_relation_joined(rid=rid)


@hooks.hook('zeromq-configuration-relation-joined')
@os_requires_version('kilo', 'neutron-server')
def zeromq_configuration_relation_joined(relid=None):
    relation_set(relation_id=relid,
                 topics=" ".join(get_topics()),
                 users="neutron")


@hooks.hook('neutron-plugin-api-subordinate-relation-joined')
def neutron_plugin_api_subordinate_relation_joined(relid=None):
    relation_data = {'neutron-api-ready': 'no'}
    if is_api_ready(CONFIGS):
        relation_data['neutron-api-ready'] = "yes"
    relation_set(relation_id=relid, **relation_data)


@hooks.hook('zeromq-configuration-relation-changed',
            'neutron-plugin-api-subordinate-relation-changed')
@restart_on_change(restart_map(), stopstart=True)
def zeromq_configuration_relation_changed():
    CONFIGS.write_all()


@hooks.hook('nrpe-external-master-relation-joined',
            'nrpe-external-master-relation-changed')
def update_nrpe_config():
    # python-dbus is used by check_upstart_job
    apt_install('python-dbus')
    hostname = nrpe.get_nagios_hostname()
    current_unit = nrpe.get_nagios_unit_name()
    nrpe_setup = nrpe.NRPE(hostname=hostname)
    nrpe.copy_nrpe_checks()
    nrpe.add_init_service_checks(nrpe_setup, services(), current_unit)

    nrpe.add_haproxy_checks(nrpe_setup, current_unit)
    nrpe_setup.write()


@hooks.hook('etcd-proxy-relation-joined')
@hooks.hook('etcd-proxy-relation-changed')
def etcd_proxy_force_restart(relation_id=None):
    # note(cory.benfield): Mostly etcd does not require active management,
    # but occasionally it does require a full config nuking. This does not
    # play well with the standard neutron-api config management, so we
    # treat etcd like the special snowflake it insists on being.
    CONFIGS.register('/etc/init/etcd.conf', [EtcdContext()])
    CONFIGS.write('/etc/init/etcd.conf')

    if 'etcd-proxy' in CONFIGS.complete_contexts():
        force_etcd_restart()


@hooks.hook('midonet-relation-joined')
@hooks.hook('midonet-relation-changed')
@hooks.hook('midonet-relation-departed')
@restart_on_change(restart_map())
def midonet_changed():
    CONFIGS.write_all()


@hooks.hook('update-status')
@harden()
@harden()
def update_status():
    log('Updating status.')


def main():
    try:
        hooks.execute(sys.argv)
    except UnregisteredHookError as e:
        log('Unknown hook {} - skipping.'.format(e))
    set_os_workload_status(CONFIGS, REQUIRED_INTERFACES,
                           charm_func=check_optional_relations)


if __name__ == '__main__':
    main()