# 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.

from nova.tests import fixtures as nova_fixtures
from nova.tests.functional.api import client
from nova.tests.functional import integrated_helpers


class BFVRescue(integrated_helpers.ProviderUsageBaseTestCase):
    """Base class for various boot from volume rescue tests."""

    def setUp(self):
        super(BFVRescue, self).setUp()
        self.useFixture(nova_fixtures.CinderFixture(self))
        self._start_compute(host='host1')

    def _create_bfv_server(self):
        server_request = self._build_server(networks=[])
        server_request.pop('imageRef')
        server_request['block_device_mapping_v2'] = [{
            'boot_index': 0,
            'uuid': nova_fixtures.CinderFixture.IMAGE_BACKED_VOL,
            'source_type': 'volume',
            'destination_type': 'volume'}]
        server = self.api.post_server({'server': server_request})
        self._wait_for_state_change(server, 'ACTIVE')
        return server


class DisallowBFVRescuev286(BFVRescue):
    """Asserts that BFV rescue requests fail prior to microversion 2.87.
    """
    compute_driver = 'fake.MediumFakeDriver'
    microversion = '2.86'

    def test_bfv_rescue_not_supported(self):
        server = self._create_bfv_server()
        ex = self.assertRaises(client.OpenStackApiException,
            self.api.post_server_action, server['id'], {'rescue': {
            'rescue_image_ref': '155d900f-4e14-4e4c-a73d-069cbf4541e6'}})
        self.assertEqual(400, ex.response.status_code)
        self.assertIn('Cannot rescue a volume-backed instance',
                      ex.response.text)


class DisallowBFVRescuev286WithTrait(BFVRescue):
    """Asserts that BFV rescue requests fail prior to microversion 2.87 even
       when the required COMPUTE_RESCUE_BFV trait is reported by the compute.
    """
    compute_driver = 'fake.RescueBFVDriver'
    microversion = '2.86'

    def test_bfv_rescue_not_supported(self):
        server = self._create_bfv_server()
        ex = self.assertRaises(client.OpenStackApiException,
            self.api.post_server_action, server['id'], {'rescue': {
            'rescue_image_ref': '155d900f-4e14-4e4c-a73d-069cbf4541e6'}})
        self.assertEqual(400, ex.response.status_code)
        self.assertIn('Cannot rescue a volume-backed instance',
                      ex.response.text)


class DisallowBFVRescuev287WithoutTrait(BFVRescue):
    """Asserts that BFV rescue requests fail with microversion 2.87 (or later)
    when the required COMPUTE_RESCUE_BFV trait is not reported by the compute.
    """
    compute_driver = 'fake.MediumFakeDriver'
    microversion = '2.87'

    def test_bfv_rescue_not_supported(self):
        server = self._create_bfv_server()
        ex = self.assertRaises(client.OpenStackApiException,
            self.api.post_server_action, server['id'], {'rescue': {
            'rescue_image_ref': '155d900f-4e14-4e4c-a73d-069cbf4541e6'}})
        self.assertEqual(400, ex.response.status_code)
        self.assertIn('Host unable to rescue a volume-backed instance',
                      ex.response.text)


class AllowBFVRescuev287WithTrait(BFVRescue):
    """Asserts that BFV rescue requests pass with microversion 2.87 (or later)
    when the required COMPUTE_RESCUE_BFV trait is reported by the compute.
    """
    compute_driver = 'fake.RescueBFVDriver'
    microversion = '2.87'

    def test_bfv_rescue_supported(self):
        server = self._create_bfv_server()
        self.api.post_server_action(server['id'], {'rescue': {
            'rescue_image_ref': '155d900f-4e14-4e4c-a73d-069cbf4541e6'}})
        self._wait_for_state_change(server, 'RESCUE')