#!/usr/bin/python

import os
import utils
import sys
import shutil
import uuid
from subprocess import check_call

import lib.openstack_common as openstack
import swift_utils as swift

def install():
    src = utils.config_get('openstack-origin')
    if src != 'distro':
        openstack.configure_installation_source(src)
    check_call(['apt-get', 'update'])
    rel = openstack.get_os_codename_install_source(src)

    pkgs = swift.determine_packages(rel)
    utils.install(*pkgs)

    swift.ensure_swift_dir()

    # initialize swift configs.
    # swift.conf hash
    ctxt = {
        'swift_hash': swift.get_swift_hash()
    }
    with open(swift.SWIFT_CONF, 'w') as conf:
        conf.write(swift.render_config(swift.SWIFT_CONF, ctxt))

    # swift-proxy.conf
    swift.write_proxy_config()

    # memcached.conf
    ctxt = { 'proxy_ip': utils.get_host_ip() }
    with open(swift.MEMCACHED_CONF, 'w') as conf:
        conf.write(swift.render_config(swift.MEMCACHED_CONF, ctxt))

    # generate or setup SSL certificate
    swift.configure_ssl()

    # initialize new storage rings.
    for ring in swift.SWIFT_RINGS.iteritems():
        swift.initialize_ring(ring[1],
                              utils.config_get('partition-power'),
                              utils.config_get('replicas'),
                              utils.config_get('min-hours'))

    # configure a directory on webserver for distributing rings.
    if not os.path.isdir(swift.WWW_DIR):
        os.mkdir(swift.WWW_DIR, 0755)
    uid, gid = swift.swift_user()
    os.chown(swift.WWW_DIR, uid, gid)
    swift.write_apache_config()


def keystone_joined(relid=None):
    hostname = utils.unit_get('private-address')
    port = utils.config_get('bind-port')
    ssl = utils.config_get('use-https')
    if ssl == 'yes':
        proto = 'https'
    else:
        proto = 'http'
    admin_url = '%s://%s:%s' % (proto, hostname, port)
    internal_url = public_url = '%s/v1/AUTH_$(tenant_id)s' % admin_url
    utils.relation_set(service='swift',
                       region=utils.config_get('region'),
                       public_url=public_url, internal_url=internal_url,
                       admin_url=admin_url,
                       requested_roles=utils.config_get('operator-roles'),
                       rid=relid)


def keystone_changed():
    swift.write_proxy_config()


def balance_rings():
    '''handle doing ring balancing and distribution.'''
    new_ring = False
    for ring in swift.SWIFT_RINGS.itervalues():
        if swift.balance_ring(ring):
            utils.juju_log('INFO', 'Balanced ring %s' % ring)
            new_ring = True
    if not new_ring:
        return

    for ring in swift.SWIFT_RINGS.keys():
        f = '%s.ring.gz' % ring
        shutil.copyfile(os.path.join(swift.SWIFT_CONF_DIR, f),
                        os.path.join(swift.WWW_DIR, f))

    msg = 'Broadcasting notification to all storage nodes that new '\
          'ring is ready for consumption.'
    utils.juju_log('INFO', msg)

    www_dir = swift.WWW_DIR.split('/var/www/')[1]
    trigger = uuid.uuid4()
    swift_hash = swift.get_swift_hash()
    # notify storage nodes that there is a new ring to fetch.
    for relid in utils.relation_ids('swift-storage'):
        utils.relation_set(rid=relid, swift_hash=swift_hash,
                           www_dir=www_dir, trigger=trigger)
    swift.proxy_control('restart')

def storage_changed():
    account_port = utils.config_get('account-ring-port')
    object_port = utils.config_get('object-ring-port')
    container_port = utils.config_get('container-ring-port')
    zone = swift.get_zone(utils.config_get('zone-assignment'))
    node_settings = {
        'ip': utils.get_host_ip(utils.relation_get('private-address')),
        'zone': zone,
        'account_port': utils.relation_get('account_port'),
        'object_port': utils.relation_get('object_port'),
        'container_port': utils.relation_get('container_port'),
    }
    if None in node_settings.itervalues():
        utils.juju_log('INFO', 'storage_changed: Relation not ready.')
        return None

    for k in ['zone', 'account_port', 'object_port', 'container_port']:
        node_settings[k] = int(node_settings[k])

    # Grant new node access to rings via apache.
    swift.write_apache_config()

    # allow for multiple devs per unit, passed along as a : separated list
    devs = utils.relation_get('device').split(':')
    for dev in devs:
        node_settings['device'] = dev
        for ring in swift.SWIFT_RINGS.itervalues():
            if not swift.exists_in_ring(ring, node_settings):
                swift.add_to_ring(ring, node_settings)

    if swift.should_balance([r for r in swift.SWIFT_RINGS.itervalues()]):
        balance_rings()

def storage_broken():
    swift.write_apache_config()

def config_changed():
    relids = utils.relation_ids('identity-service')
    if relids:
        for relid in relids:
            keystone_joined(relid)
    swift.write_proxy_config()

hooks = {
    'install': install,
    'config-changed': config_changed,
    'identity-service-relation-joined': keystone_joined,
    'identity-service-relation-changed': keystone_changed,
    'swift-storage-relation-changed': storage_changed,
    'swift-storage-relation-broken': storage_broken,
}

utils.do_hooks(hooks)

sys.exit(0)