#
# Copyright 2012 New Dream Network, LLC (DreamHost)
#
# 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.
"""Simple logging storage backend.
"""

from oslo_log import log

from ceilometer.i18n import _LI
from ceilometer.storage import base

LOG = log.getLogger(__name__)


class Connection(base.Connection):
    """Log the data."""

    def upgrade(self):
        pass

    def clear(self):
        pass

    def record_metering_data(self, data):
        """Write the data to the backend storage system.

        :param data: a dictionary such as returned by
                     ceilometer.meter.meter_message_from_counter.
        """
        LOG.info(_LI('metering data %(counter_name)s for %(resource_id)s: '
                     '%(counter_volume)s')
                 % ({'counter_name': data['counter_name'],
                     'resource_id': data['resource_id'],
                     'counter_volume': data['counter_volume']}))

    def clear_expired_metering_data(self, ttl):
        """Clear expired data from the backend storage system.

        Clearing occurs according to the time-to-live.
        :param ttl: Number of seconds to keep records for.
        """
        LOG.info(_LI("Dropping metering data with TTL %d"), ttl)

    def get_resources(self, user=None, project=None, source=None,
                      start_timestamp=None, start_timestamp_op=None,
                      end_timestamp=None, end_timestamp_op=None,
                      metaquery=None, resource=None, limit=None):
        """Return an iterable of dictionaries containing resource information.

        { 'resource_id': UUID of the resource,
          'project_id': UUID of project owning the resource,
          'user_id': UUID of user owning the resource,
          'timestamp': UTC datetime of last update to the resource,
          'metadata': most current metadata for the resource,
          'meter': list of the meters reporting data for the resource,
          }

        :param user: Optional ID for user that owns the resource.
        :param project: Optional ID for project that owns the resource.
        :param source: Optional source filter.
        :param start_timestamp: Optional modified timestamp start range.
        :param start_timestamp_op: Optional start time operator, like gt, ge.
        :param end_timestamp: Optional modified timestamp end range.
        :param end_timestamp_op: Optional end time operator, like lt, le.
        :param metaquery: Optional dict with metadata to match on.
        :param resource: Optional resource filter.
        :param limit: Maximum number of results to return.
        """
        return []

    def get_meters(self, user=None, project=None, resource=None, source=None,
                   limit=None, metaquery=None, unique=False):
        """Return an iterable of dictionaries containing meter information.

        { 'name': name of the meter,
          'type': type of the meter (gauge, delta, cumulative),
          'resource_id': UUID of the resource,
          'project_id': UUID of project owning the resource,
          'user_id': UUID of user owning the resource,
          }

        :param user: Optional ID for user that owns the resource.
        :param project: Optional ID for project that owns the resource.
        :param resource: Optional resource filter.
        :param source: Optional source filter.
        :param limit: Maximum number of results to return.
        :param metaquery: Optional dict with metadata to match on.
        :param unique: If set to true, return only unique meter information.
        """
        return []

    def get_samples(self, sample_filter, limit=None):
        """Return an iterable of samples.

        Items are created by
        ceilometer.publisher.utils.meter_message_from_counter.
        """
        return []

    def get_meter_statistics(self, sample_filter, period=None, groupby=None,
                             aggregate=None):
        """Return a dictionary containing meter statistics.

        Meter statistics is described by the query parameters.
        The filter must have a meter value set.

        { 'min':
          'max':
          'avg':
          'sum':
          'count':
          'period':
          'period_start':
          'period_end':
          'duration':
          'duration_start':
          'duration_end':
          }
        """
        return []
