# -*- coding: utf-8 -*- #
# Copyright 2018 Google 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.
"""List usable subnets command."""

from __future__ import absolute_import
from __future__ import division
from __future__ import unicode_literals

from apitools.base.py import exceptions as apitools_exceptions

from googlecloudsdk.api_lib.container import util
from googlecloudsdk.calliope import base
from googlecloudsdk.calliope import exceptions
from googlecloudsdk.core import log
from googlecloudsdk.core import properties
from googlecloudsdk.core import resources


def _GetUriFunction(resource):
  return resources.REGISTRY.ParseRelativeName(resource.subnetwork,
                                              'compute.subnetworks').SelfLink()


class ListUsable(base.ListCommand):
  r"""List subnets usable for cluster creation in a specific project.

      Usability of subnetworks for cluster creation is dependent on the IAM
      policy of the project's Google Kubernetes Engine Service Account. Use the
      `--project` flag to evaluate subnet usability in different projects. This
      list may differ from the list returned by Google Compute Engine's
      `list-usable` command, which returns subnets only usable by the caller.

      To show subnetworks shared from a Shared-VPC host project, use
      `--network-project` to specify the project that owns the subnetworks.

      ## EXAMPLES

      List all subnetworks usable for cluster creation in project `my-project`.

          $ {command} \
            --project my-project

      List all subnetworks existing in project `my-shared-host-project` usable
      for cluster creation in project `my-service-project`.

          $ {command} \
             --project my-service-project \
             --network-project my-shared-host-project

  """

  @staticmethod
  def Args(parser):
    """Register flags for this command.

    Args:
      parser: An argparse.ArgumentParser-like object. It is mocked out in order
        to capture some information, but behaves like an ArgumentParser.
    """

    parser.add_argument(
        '--network-project',
        help="""\
        The project owning the subnetworks returned. This field is translated
        into the expression `networkProjectId=[PROJECT_ID]` and ANDed to
        the `--filter` flag value.

        Defaults to the *--project* value.
""")

    display_format = 'table({fields})'.format(fields=','.join([
        'subnetwork.segment(-5):label=PROJECT',
        'subnetwork.segment(-3):label=REGION',
        'network.segment(-1):label=NETWORK',
        'subnetwork.segment(-1):label=SUBNET', 'ipCidrRange:label=RANGE', """
        secondaryIpRanges:format="table[box](
          rangeName:label=SECONDARY_RANGE_NAME,
          ipCidrRange,
          status.enum(UsableSubnetworkSecondaryRange.Status)
        )":label=SECONDARY_RANGES
        """
    ]))
    parser.display_info.AddFormat(display_format)
    parser.display_info.AddUriFunc(_GetUriFunction)

    status_enum = {
        'UsableSubnetworkSecondaryRange.Status::enum': {
            'UNKNOWN': 'Unknown',
            'UNUSED': 'usable for pods or services',
            'IN_USE_SERVICE': 'unusable',
            'IN_USE_SHAREABLE_POD': 'usable for pods',
            'IN_USE_MANAGED_POD': 'unusable'
        }
    }
    parser.display_info.AddTransforms(status_enum)

  def Run(self, args):
    """This is what gets called when the user runs this command.

    Args:
      args: an argparse namespace. All the arguments that were provided to this
        command invocation.

    Returns:
      Some value that we want to have printed later.
    """
    adapter = self.context['api_adapter']
    project_ref = adapter.registry.Create(
        'container.projects',
        projectsId=properties.VALUES.core.project.GetOrFail())

    try:
      resp = adapter.ListUsableSubnets(project_ref, args.network_project,
                                       args.filter).subnetworks
      # De-duplicate status messages.
      msg_set = set()
      for subnet in resp:
        msg = subnet.statusMessage
        if msg and msg not in msg_set:
          msg_set.add(msg)
          log.warning(msg)
      return resp

    except apitools_exceptions.HttpError as error:
      raise exceptions.HttpException(error, util.HTTP_ERROR_FORMAT)
