# Copyright (c) 2013-2016 Hewlett Packard Enterprise Development LP
#
# Redistribution and use of this software in source and binary forms,
# with or without modification, are permitted provided that the following
# conditions are met:
#
#   Redistributions of source code must retain the above copyright notice,
#   this list of conditions and the following disclaimer.
#
#   Redistributions in binary form must reproduce the above copyright
#   notice, this list of conditions and the following disclaimer in the
#   documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

import datetime

from requestbuilder import Arg
from requestbuilder.exceptions import ArgumentError
from requestbuilder.mixins import TabifyingMixin
from requestbuilder.response import PaginatedResponse

from euca2ools.commands.argtypes import delimited_list
from euca2ools.commands.monitoring import CloudWatchRequest
from euca2ools.commands.monitoring.argtypes import cloudwatch_dimension


class GetMetricStatistics(CloudWatchRequest, TabifyingMixin):
    DESCRIPTION = "Show a metric's statistics"
    ARGS = [Arg('MetricName', metavar='METRIC',
                help='name of the metric to get statistics for (required)'),
            Arg('-n', '--namespace', dest='Namespace', required=True,
                help="the metric's namespace (required)"),
            Arg('-s', '--statistics', dest='Statistics.member', required=True,
                metavar='STAT1,STAT2,...', type=delimited_list(','),
                help='the metric statistics to show (at least 1 required)'),
            Arg('--dimensions', dest='Dimensions.member',
                metavar='KEY1=VALUE1,KEY2=VALUE2,...',
                type=delimited_list(',', item_type=cloudwatch_dimension),
                help='the dimensions of the metric to show'),
            Arg('--start-time', dest='StartTime',
                metavar='YYYY-MM-DDThh:mm:ssZ', help='''earliest time to
                retrieve data points for (default: one hour ago)'''),
            Arg('--end-time', dest='EndTime',
                metavar='YYYY-MM-DDThh:mm:ssZ', help='''latest time to retrieve
                data points for (default: now)'''),
            Arg('--period', dest='Period', metavar='SECONDS', type=int,
                default=60, help='''granularity of the returned data
                points (must be a multiple of 60) (default: 60)'''),
            Arg('--unit', dest='Unit', help='unit the metric is reported in')]
    LIST_TAGS = ['Datapoints']

    # noinspection PyExceptionInherit
    def configure(self):
        CloudWatchRequest.configure(self)
        if self.args.get('period'):
            if self.args['period'] <= 0:
                raise ArgumentError(
                    'argument --period: value must be positive')
            elif self.args['period'] % 60 != 0:
                raise ArgumentError(
                    'argument --period: value must be a multiple of 60')

    def main(self):
        now = datetime.datetime.utcnow()
        then = now - datetime.timedelta(hours=1)
        if not self.args.get('StartTime'):
            self.params['StartTime'] = then.strftime('%Y-%m-%dT%H:%M:%SZ')
        if not self.args.get('EndTime'):
            self.params['EndTime'] = now.strftime('%Y-%m-%dT%H:%M:%SZ')

        return PaginatedResponse(self, (None,), ('Datapoints',))

    # pylint: disable=no-self-use
    def prepare_for_page(self, page):
        self.params['NextToken'] = page
    # pylint: enable=no-self-use

    # pylint: disable=no-self-use
    def get_next_page(self, response):
        return response.get('NextToken') or None
    # pylint: enable=no-self-use

    def print_result(self, result):
        points = []
        for point in result.get('Datapoints', []):
            timestamp = point.get('Timestamp', '')
            try:
                parsed = datetime.datetime.strptime(timestamp,
                                                    '%Y-%m-%dT%H:%M:%SZ')
                timestamp = parsed.strftime('%Y-%m-%d %H:%M:%S')
            except ValueError:
                # We'll just print it verbatim
                pass
            points.append((timestamp, point.get('SampleCount'),
                           point.get('Average'), point.get('Sum'),
                           point.get('Minimum'), point.get('Maximum'),
                           point.get('Unit')))
        for point in sorted(points):
            print self.tabify(point)