""" List, create and manage repositories. """

import logging
import datetime
import features

from collections import defaultdict
from datetime import timedelta, datetime

from flask import request, abort

from app import dockerfile_build_queue, tuf_metadata_api
from endpoints.api import (
  format_date, nickname, log_action, validate_json_request, require_repo_read, require_repo_write,
  require_repo_admin, RepositoryParamResource, resource, parse_args, ApiResource, request_error,
  require_scope, path_param, page_support, query_param, truthy_bool, show_if)
from endpoints.api.repository_models_pre_oci import pre_oci_model as model
from endpoints.exception import (
  Unauthorized, NotFound, InvalidRequest, ExceedsLicenseException, DownstreamIssue)
from endpoints.api.billing import lookup_allowed_private_repos, get_namespace_plan
from endpoints.api.subscribe import check_repository_usage

from auth.permissions import (ModifyRepositoryPermission, AdministerRepositoryPermission,
                              CreateRepositoryPermission, ReadRepositoryPermission)
from auth.auth_context import get_authenticated_user
from auth import scopes
from util.names import REPOSITORY_NAME_REGEX

logger = logging.getLogger(__name__)

REPOS_PER_PAGE = 100
MAX_DAYS_IN_3_MONTHS = 92


def check_allowed_private_repos(namespace):
  """ Checks to see if the given namespace has reached its private repository limit. If so,
      raises a ExceedsLicenseException.
  """
  # Not enabled if billing is disabled.
  if not features.BILLING:
    return

  if not lookup_allowed_private_repos(namespace):
    raise ExceedsLicenseException()


@resource('/v1/repository')
class RepositoryList(ApiResource):
  """Operations for creating and listing repositories."""
  schemas = {
    'NewRepo': {
      'type': 'object',
      'description': 'Description of a new repository',
      'required': [
        'repository',
        'visibility',
        'description',
      ],
      'properties': {
        'repository': {
          'type': 'string',
          'description': 'Repository name',
        },
        'visibility': {
          'type': 'string',
          'description': 'Visibility which the repository will start with',
          'enum': [
            'public',
            'private',
          ],
        },
        'namespace': {
          'type':
            'string',
          'description': ('Namespace in which the repository should be created. If omitted, the '
                          'username of the caller is used'),
        },
        'description': {
          'type': 'string',
          'description': 'Markdown encoded description for the repository',
        },
        'repo_kind': {
          'type': ['string', 'null'],
          'description': 'The kind of repository',
          'enum': ['image', 'application', None],
        }
      },
    },
  }

  @require_scope(scopes.CREATE_REPO)
  @nickname('createRepo')
  @validate_json_request('NewRepo')
  def post(self):
    """Create a new repository."""
    owner = get_authenticated_user()
    req = request.get_json()

    if owner is None and 'namespace' not in 'req':
      raise InvalidRequest('Must provide a namespace or must be logged in.')

    namespace_name = req['namespace'] if 'namespace' in req else owner.username

    permission = CreateRepositoryPermission(namespace_name)
    if permission.can():
      repository_name = req['repository']
      visibility = req['visibility']

      if model.repo_exists(namespace_name, repository_name):
        raise request_error(message='Repository already exists')

      visibility = req['visibility']
      if visibility == 'private':
        check_allowed_private_repos(namespace_name)

      # Verify that the repository name is valid.
      if not REPOSITORY_NAME_REGEX.match(repository_name):
        raise InvalidRequest('Invalid repository name')

      kind = req.get('repo_kind', 'image') or 'image'
      model.create_repo(namespace_name, repository_name, owner, req['description'],
                        visibility=visibility, repo_kind=kind)

      log_action('create_repo', namespace_name,
                 {'repo': repository_name,
                  'namespace': namespace_name}, repo_name=repository_name)
      return {
        'namespace': namespace_name,
        'name': repository_name,
        'kind': kind,
      }, 201

    raise Unauthorized()

  @require_scope(scopes.READ_REPO)
  @nickname('listRepos')
  @parse_args()
  @query_param('namespace', 'Filters the repositories returned to this namespace', type=str)
  @query_param('starred', 'Filters the repositories returned to those starred by the user',
               type=truthy_bool, default=False)
  @query_param('public', 'Adds any repositories visible to the user by virtue of being public',
               type=truthy_bool, default=False)
  @query_param('last_modified', 'Whether to include when the repository was last modified.',
               type=truthy_bool, default=False)
  @query_param('popularity', 'Whether to include the repository\'s popularity metric.',
               type=truthy_bool, default=False)
  @query_param('repo_kind', 'The kind of repositories to return', type=str, default='image')
  @page_support()
  def get(self, page_token, parsed_args):
    """ Fetch the list of repositories visible to the current user under a variety of situations.
    """
    # Ensure that the user requests either filtered by a namespace, only starred repositories,
    # or public repositories. This ensures that the user is not requesting *all* visible repos,
    # which can cause a surge in DB CPU usage.
    if not parsed_args['namespace'] and not parsed_args['starred'] and not parsed_args['public']:
      raise InvalidRequest('namespace, starred or public are required for this API call')

    user = get_authenticated_user()
    username = user.username if user else None
    last_modified = parsed_args['last_modified']
    popularity = parsed_args['popularity']

    if parsed_args['starred'] and not username:
      # No repositories should be returned, as there is no user.
      abort(400)

    repos, next_page_token = model.get_repo_list(
      parsed_args['starred'], user, parsed_args['repo_kind'], parsed_args['namespace'], username,
      parsed_args['public'], page_token, last_modified, popularity)

    return {'repositories': [repo.to_dict() for repo in repos]}, next_page_token


@resource('/v1/repository/<apirepopath:repository>')
@path_param('repository', 'The full path of the repository. e.g. namespace/name')
class Repository(RepositoryParamResource):
  """Operations for managing a specific repository."""
  schemas = {
    'RepoUpdate': {
      'type': 'object',
      'description': 'Fields which can be updated in a repository.',
      'required': ['description',],
      'properties': {
        'description': {
          'type': 'string',
          'description': 'Markdown encoded description for the repository',
        },
      }
    }
  }

  @parse_args()
  @query_param('includeStats', 'Whether to include action statistics', type=truthy_bool,
               default=False)
  @require_repo_read
  @nickname('getRepo')
  def get(self, namespace, repository, parsed_args):
    """Fetch the specified repository."""
    logger.debug('Get repo: %s/%s' % (namespace, repository))
    repo = model.get_repo(namespace, repository, get_authenticated_user())
    if repo is None:
      raise NotFound()

    repo_data = repo.to_dict()
    repo_data['can_write'] = ModifyRepositoryPermission(namespace, repository).can()
    repo_data['can_admin'] = AdministerRepositoryPermission(namespace, repository).can()

    if parsed_args['includeStats'] and repo.repository_base_elements.kind_name != 'application':
      stats = []
      found_dates = {}

      for count in repo.counts:
        stats.append(count.to_dict())
        found_dates['%s/%s' % (count.date.month, count.date.day)] = True

      # Fill in any missing stats with zeros.
      for day in range(1, MAX_DAYS_IN_3_MONTHS):
        day_date = datetime.now() - timedelta(days=day)
        key = '%s/%s' % (day_date.month, day_date.day)
        if key not in found_dates:
          stats.append({
            'date': day_date.date().isoformat(),
            'count': 0,
          })

      repo_data['stats'] = stats
    return repo_data

  @require_repo_write
  @nickname('updateRepo')
  @validate_json_request('RepoUpdate')
  def put(self, namespace, repository):
    """ Update the description in the specified repository. """
    if not model.repo_exists(namespace, repository):
      raise NotFound()

    values = request.get_json()
    model.set_description(namespace, repository, values['description'])

    log_action('set_repo_description', namespace,
               {'repo': repository,
                'namespace': namespace,
                'description': values['description']}, repo_name=repository)
    return {'success': True}

  @require_repo_admin
  @nickname('deleteRepository')
  def delete(self, namespace, repository):
    """ Delete a repository. """
    username = model.purge_repository(namespace, repository)

    if features.BILLING:
      plan = get_namespace_plan(namespace)
      model.check_repository_usage(username, plan)

    # Remove any builds from the queue.
    dockerfile_build_queue.delete_namespaced_items(namespace, repository)

    log_action('delete_repo', namespace, {'repo': repository, 'namespace': namespace})
    return '', 204


@resource('/v1/repository/<apirepopath:repository>/changevisibility')
@path_param('repository', 'The full path of the repository. e.g. namespace/name')
class RepositoryVisibility(RepositoryParamResource):
  """ Custom verb for changing the visibility of the repository. """
  schemas = {
    'ChangeVisibility': {
      'type': 'object',
      'description': 'Change the visibility for the repository.',
      'required': ['visibility',],
      'properties': {
        'visibility': {
          'type': 'string',
          'description': 'Visibility which the repository will start with',
          'enum': [
            'public',
            'private',
          ],
        },
      }
    }
  }

  @require_repo_admin
  @nickname('changeRepoVisibility')
  @validate_json_request('ChangeVisibility')
  def post(self, namespace, repository):
    """ Change the visibility of a repository. """
    if model.repo_exists(namespace, repository):
      values = request.get_json()
      visibility = values['visibility']
      if visibility == 'private':
        check_allowed_private_repos(namespace)

      model.set_repository_visibility(namespace, repository, visibility)
      log_action('change_repo_visibility', namespace,
                 {'repo': repository,
                  'namespace': namespace,
                  'visibility': values['visibility']}, repo_name=repository)
      return {'success': True}


@resource('/v1/repository/<apirepopath:repository>/changetrust')
@path_param('repository', 'The full path of the repository. e.g. namespace/name')
class RepositoryTrust(RepositoryParamResource):
  """ Custom verb for changing the trust settings of the repository. """
  schemas = {
    'ChangeRepoTrust': {
      'type': 'object',
      'description': 'Change the trust settings for the repository.',
      'required': ['trust_enabled',],
      'properties': {
        'trust_enabled': {
          'type': 'boolean',
          'description': 'Whether or not signing is enabled for the repository.'
        },
      }
    }
  }

  @show_if(features.SIGNING)
  @require_repo_admin
  @nickname('changeRepoTrust')
  @validate_json_request('ChangeRepoTrust')
  def post(self, namespace, repository):
    """ Change the visibility of a repository. """
    if not model.repo_exists(namespace, repository):
      raise NotFound()

    tags, _ = tuf_metadata_api.get_default_tags_with_expiration(namespace, repository)
    if tags and not tuf_metadata_api.delete_metadata(namespace, repository):
      raise DownstreamIssue('Unable to delete downstream trust metadata')

    values = request.get_json()
    model.set_trust(namespace, repository, values['trust_enabled'])

    log_action(
      'change_repo_trust', namespace,
      {'repo': repository,
       'namespace': namespace,
       'trust_enabled': values['trust_enabled']}, repo_name=repository)

    return {'success': True}