# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2011 Nicira Networks, Inc.
# All Rights Reserved.
#
#    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.

"""
Routines for configuring Quantum
"""

import logging
import logging.handlers
import os
import sys

from paste import deploy

from quantum.openstack.common import cfg
from quantum.version import version_string


LOG = logging.getLogger(__name__)

bind_opts = [
    cfg.StrOpt('bind_host', default='0.0.0.0'),
    cfg.IntOpt('bind_port', default=9696),
    cfg.StrOpt('api_paste_config', default="api-paste.ini"),
    cfg.StrOpt('api_extensions_path', default=""),
    cfg.StrOpt('policy_file', default="policy.json"),
    cfg.StrOpt('core_plugin',
               default='quantum.plugins.sample.SamplePlugin.FakePlugin'),
    cfg.StrOpt('base_mac', default="fa:16:3e:00:00:00"),
    cfg.IntOpt('mac_generation_retries', default=16)
]

# Register the configuration options
cfg.CONF.register_opts(bind_opts)


def parse(args):
    cfg.CONF(args=args, project='quantum',
             version='%%prog %s' % version_string())


def setup_logging(conf):
    """
    Sets up the logging options for a log with supplied name

    :param conf: a cfg.ConfOpts object
    """

    if conf.log_config:
        # Use a logging configuration file for all settings...
        if os.path.exists(conf.log_config):
            logging.config.fileConfig(conf.log_config)
            return
        else:
            raise RuntimeError("Unable to locate specified logging "
                               "config file: %s" % conf.log_config)

    root_logger = logging.root
    if conf.debug:
        root_logger.setLevel(logging.DEBUG)
    elif conf.verbose:
        root_logger.setLevel(logging.INFO)
    else:
        root_logger.setLevel(logging.WARNING)

    formatter = logging.Formatter(conf.log_format, conf.log_date_format)

    if conf.use_syslog:
        try:
            facility = getattr(logging.handlers.SysLogHandler,
                               conf.syslog_log_facility)
        except AttributeError:
            raise ValueError(_("Invalid syslog facility"))

        handler = logging.handlers.SysLogHandler(address='/dev/log',
                                                 facility=facility)
    elif conf.log_file:
        logfile = conf.log_file
        if conf.log_dir:
            logfile = os.path.join(conf.log_dir, logfile)
        handler = logging.handlers.WatchedFileHandler(logfile)
    else:
        handler = logging.StreamHandler(sys.stdout)

    handler.setFormatter(formatter)
    root_logger.addHandler(handler)


def load_paste_app(app_name):
    """
    Builds and returns a WSGI app from a paste config file.

    :param app_name: Name of the application to load
    :raises RuntimeError when config file cannot be located or application
            cannot be loaded from config file
    """

    config_path = os.path.abspath(cfg.CONF.find_file(
        cfg.CONF.api_paste_config))
    LOG.info("Config paste file: %s", config_path)

    try:
        app = deploy.loadapp("config:%s" % config_path, name=app_name)
    except (LookupError, ImportError):
        msg = ("Unable to load %(app_name)s from "
               "configuration file %(config_path)s.") % locals()
        LOG.exception(msg)
        raise RuntimeError(msg)
    return app
