import configparser
import os
import logging

from ucloud.common.host import HostPool
from ucloud.common.request import RequestPool
from ucloud.common.vm import VmPool
from ucloud.common.storage_handlers import FileSystemBasedImageStorageHandler, CEPHBasedImageStorageHandler
from ucloud.common.etcd_wrapper import Etcd3Wrapper

log = logging.getLogger('ucloud.config')

conf_name = 'ucloud.conf'
conf_dir = os.environ.get('UCLOUD_CONF_DIR', '/etc/ucloud')
config_file = os.path.join(conf_dir, conf_name)

config = configparser.ConfigParser(allow_no_value=True)

if os.access(config_file, os.R_OK):
    config.read(config_file)
else:
    log.warning('Configuration file not found - using defaults')

etcd_wrapper_args = ()
etcd_wrapper_kwargs = {
    'host':      config['etcd']['url'],
    'port':      config['etcd']['port'],
    'ca_cert':   config['etcd']['ca_cert'],
    'cert_cert': config['etcd']['cert_cert'],
    'cert_key':  config['etcd']['cert_key']
}

etcd_client = Etcd3Wrapper(*etcd_wrapper_args, **etcd_wrapper_kwargs)

host_pool = HostPool(etcd_client, config['etcd']['host_prefix'])
vm_pool = VmPool(etcd_client, config['etcd']['vm_prefix'])
request_pool = RequestPool(etcd_client, config['etcd']['request_prefix'])

running_vms = []

__storage_backend = config['storage']['backend']
if __storage_backend == 'filesystem':
    image_storage_handler = FileSystemBasedImageStorageHandler(
        vm_base=config['storage']['vm_dir'],
        image_base=config['storage']['image_dir']
    )
elif __storage_backend == 'ceph':
    image_storage_handler = CEPHBasedImageStorageHandler(
        vm_base=config['storage']['ceph_vm_pool'],
        image_base=config['storage']['ceph_image_pool']
    )
else:
    raise Exception('Unknown Image Storage Handler')